Paving Booklet English

VG

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Book

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n Pa

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JOSEPH VGELE AGJoseph-Vgele-Strae 167075 Ludwigshafen [email protected]

Telephone: +49 (0)621 8105 0Fax: +49 (0)621 8105 461www.voegele.info

ErgoPlus, InLine Pave, NIVELTRONIC, NIVELTRONIC Plus, NAVITRONIC, NAVITRONIC Plus, RoadScan and V-TRONIC are registered Community Trademarks of JOSEPH VGELE AG, Ludwigshafen/Rhein, Germany. PCC is a registered German Trademark of JOSEPH VGELE AG, Ludwigshafen/Rhein, Germany. NIVELTRONIC Plus and NAVITRONIC Plus are trademarks registered in the US Patent and Trademark Office to JOSEPH VGELE AG, Ludwigshafen/Rhein, Germany. Legally binding claims cannot be derived from written information or pictures contained in this brochure. Pictures may include optional extras. We reserve the right of technical or design alterations.

2280299 EN/10.12

VGELE Booklet on Paving

1FOREWORD

Dear Reader,

We are delighted to present you with our new Booklet on Paving. Following its great

success in recent years, we have completely revised our Booklet and brought it right

up-to-date. The chapters "Material Feeders", "Spray Technology" and "Two-layer Paving" are new additions due to the great advancements that have taken place in these technologies.

As a result, our Booklet on Paving remains an indispensable work of reference for

all paving professionals, trainees and students of road construction engineering.

It contains the answers to innumerable questions on the subject of "road construction using paver technology from VGELE".

We hope you enjoy reading and working with our Booklet!

JOSEPH VGELE AG

Axel Fischer Roland Schug

2 3

VGELE BOOkLET On PAVInG

2.5 Special Screed: AB 600 High Compaction Screed in TP2 Plus Version .......... 682.6 Set-Up .................................................................................................................. 70 2.6.1 Tamper ................................................................................................................................. 70 2.6.2 Pressure Bar(s) .................................................................................................................... 71 2.6.3 Tamper Shield ..................................................................................................................... 722.7 Side Plates ............................................................................................................ 73 2.7.1 Mechanical-hydraulic Side Plate .................................................................................... 73 2.7.1.1 Hydraulic Side Plate from VGELE ................................................................................. 74 2.7.1.2 Standard Side Plate from VGELE ................................................................................. 76 2.7.2 Bevel Irons ........................................................................................................................... 772.8 Screed Heating .................................................................................................... 782.9 Screed Maintenance ........................................................................................... 80 2.9.1 Daily Maintenance ............................................................................................................. 80 2.9.2 Weekly Maintenance ........................................................................................................ 82

3 Parameters Influencing the Paving Process 85

3.1 General ................................................................................................................. 863.2 Paving Material ................................................................................................... 883.3 Paving Parameters .............................................................................................. 893.4 Paver Set-Up ........................................................................................................ 893.5 Relationship Between Tamper Speed and Pave Speed .................................. 923.6 Recommended Settings for the Compacting Systems ................................... 933.7 Functions of the Hydraulic Rams for Raising / Lowering the Screed ............ 94 3.7.1 Screed Float ......................................................................................................................... 95 3.7.2 Screed Assist ....................................................................................................................... 95 3.7.3 Screed Freeze ...................................................................................................................... 95

4 Recommendations for Paving / Points to Note 97

4.1 Before Starting .................................................................................................... 98 4.1.1 Fundamentals ..................................................................................................................... 98 4.1.2 Setting the Layer Thickness ............................................................................................. 100 4.1.3 Weather Conditions when Paving Asphalt .................................................................. 104

1 Design of a Road Paver 7

1.1 Differences between Construction Machinery and Pavers .............................. 81.2 Components of a Road Paver ............................................................................... 101.3 The Floating Screed Principle .............................................................................. 121.4 Theoretical Outline of the "Floating Screed Principle"

without Grade and Slope Control ....................................................................... 131.5 Tracked Pavers and Wheeled Pavers ................................................................... 141.6 VGELE Product Overview ................................................................................... 18 1.6.1 Paver Classification ............................................................................................................. 201.7 Examples of Paver Applications .......................................................................... 22 1.7.1 Types of Paving .................................................................................................................... 22 1.7.2 InLine Pave / SprayJet Technology ................................................................................ 24 1.7.3 Paving Materials ................................................................................................................... 26

2 Screed 29

2.1 General Differences between Screeds ................................................................ 302.2 Extending Screeds ................................................................................................ 32 2.2.1 Components of the Extending Screed ........................................................................... 32 2.2.2 Compacting Systems Installed in Extending Screeds ................................................. 34 2.2.3 Extending Screeds and Bolt-on Extensions .................................................................. 36 2.2.4 Set-Up of the Extending Screed ....................................................................................... 38 2.2.5 Mechanical Design and Maintenance of the Telescoping System .......................... 482.3 Fixed-Width Screeds ............................................................................................. 50 2.3.1 Components of the Fixed-Width Screed ........................................................................ 50 2.3.2 Compacting Systems Installed in Fixed-Width Screeds ............................................. 52 2.3.3 Fixed-Width Screeds and Bolt-on Extensions ............................................................... 54 2.3.4 Set-Up of the Fixed-Width Screed ................................................................................... 602.4 Screeds for the VISION Series of Pavers .............................................................. 62 2.4.1 VF Extending Screed (with Front-Mounted Extensions) ............................................ 62 2.4.2 VR Extending Screed (with Rear-Mounted Extensions) ............................................. 64 2.4.3 Main Applications ................................................................................................................ 66

CONTENTS

4 5

VGELE BOOkLET On PAVInG COnTEnTS

5.3.3 Strips in the Lateral Areas of the Pavement ................................................................ 168 5.3.4 Patches of Mix in the Surface Texture ........................................................................... 1695.4 Imprints ................................................................................................................ 1705.5 Longitudinal Step ............................................................................................... 1705.6 Non-Uniform Surface Structure due to Crushed Grains ................................. 171

6 Paving Materials in Detail 173

6.1 General Pavement Structure ............................................................................. 1746.2 Producing Asphalt Mix ....................................................................................... 1806.3 Types of Pavement Layers .................................................................................. 1846.4 Bitumen Grades Used ......................................................................................... 1856.5 Asphalt Types and their Composition ............................................................... 186 6.5.1 Stone Mastic Asphalt ........................................................................................................ 186 6.5.2 Asphaltic Concrete (Paved Hot) ..................................................................................... 188 6.5.3 Asphaltic Binder ................................................................................................................. 190 6.5.4 Asphalt for Base Course ................................................................................................... 192 6.5.5 Porous Asphalt ................................................................................................................... 1946.6 Mix Temperatures in C ....................................................................................... 1966.7 Causes of Poor Quality Asphaltic Concrete Mixes for Hot Paving ................. 1976.8 Emulsion Types .................................................................................................... 198

7 Special Equipment and Special Methods 201

7.1 Spray Technology ................................................................................................ 2027.2 Two-Layer Paving ................................................................................................ 2087.3 Material Feeders ................................................................................................. 216

8 Index / Notes 221

4.1.4 Requirements Made on the Roadbase and its Surface ............................................ 105 4.1.5 Augers and Limiting Plates for the Auger Tunnel on an Extending Screed ........ 108 4.1.6 Definition and Preparation of the Route ...................................................................... 110 4.1.7 The Optimal Sensor for Every Paving Application ..................................................... 111 4.1.8 Ordering Asphalt from the Mixing Plant on Call ........................................................ 122 4.1.9 Preparing the Reference for Grade and Slope Control ............................................. 123 4.1.10 Correct Positioning of the Grade and Slope Sensors ................................................ 1244.2 During the Paving Process ................................................................................. 125 4.2.1 Positioning the Paver ........................................................................................................ 125 4.2.2 Head of Mix in Front of the Screed ................................................................................ 126 4.2.3 Joints in Asphalt Pavements ........................................................................................... 127 4.2.4 Expansion Joints ................................................................................................................ 131 4.2.5 Paving Hot to Cold .......................................................................................................... 132 4.2.6 Paving Hot to Hot ........................................................................................................... 133 4.2.7 Duties of the Paving Team during the Paving Process ............................................. 134 4.2.8 Tools for Continuous Verification of the Paved Result .............................................. 1364.3 After Paving ......................................................................................................... 138 4.3.1 Subsequent Compaction by Rolling ............................................................................. 138 4.3.2 Rules for Rolling and Avoiding Errors ........................................................................... 142 4.3.3 Measurement of Density and Surface Accuracy ........................................................ 143 4.3.4 Cleaning, Daily Maintenance and Completion of the Job Site ............................... 144

5 Imperfect Paving 147

5.1 Systematic Elimination of Paving Errors .......................................................... 1485.2 Paving Problems / Paving Errors ....................................................................... 158 5.2.1 Irregularities when Passing over Mix ............................................................................ 158 5.2.2 Pavement Irregularities due to Large Screed Planing Angle .................................. 159 5.2.3 Hump Formed when Resuming Paving ....................................................................... 160 5.2.4 Short Irregularities in Transverse Direction ................................................................. 161 5.2.5 Periodic Irregularities in Longitudinal Direction ........................................................ 1625.3 Segregation in General ...................................................................................... 164 5.3.1 Transverse Strips ................................................................................................................ 166 5.3.2 Strips in the Middle of the Pavement ........................................................................... 167

6 7


1 Design of a Road Paver 7

1.1 Differences between Construction Machinery and Pavers ................................ 81.2 Components of a Road Paver ............................................................................... 101.3 The Floating Screed Principle .............................................................................. 121.4 Theoretical Outline of the "Floating Screed Principle"

without Grade and Slope Control ....................................................................... 131.5 Tracked Pavers and Wheeled Pavers ................................................................... 141.6 VGELE Product Overview ................................................................................... 18 1.6.1 Paver Classification .............................................................................................................. 201.7 Examples of Paver Applications .......................................................................... 22 1.7.1 Types of Paving .................................................................................................................... 22 1.7.2 InLine Pave / SprayJet Technology ................................................................................ 24 1.7.3 Paving Materials ................................................................................................................... 26

8 9

VGELE BOOkLET On PAVInG 1. DESIGn OF A ROAD PAVER

1.1 Differences between Construction Machinery and Pavers

As a general rule, paving materials can be spread and levelled with a bulldozer, grader or paver.

Because of their superior physical properties, however, pavers have now replaced bulldozers and graders.

When a bulldozer passes over irregularities in the ground, these are extensively transmitted to the blade, as the leverage between blade and the irregularity is too short (see diagram) and short irregularities can consequently only be levelled out to a limited extent.

On a paver, however, the screed is separate from the tractor unit: it floats! As a result, the screed has a very strong self-levelling effect when passing over minor irregularities. Whats more, the kinematic conditions height of the irregularity in relation to the lift of the screeds leading edge via the long screed arm ensure that such short irregularities are levelled out at a ratio of 1:5.

For this reason, a paver should be used for paving even in the lowest layers in order to obtain an increasingly level result with each successive layer.

Bulldozer

The working tool (blade) is firmly linked to the chassis via hydraulic rams. When passing over irregularities in the ground, these are transmitted to the blade to a greater extent, unless counteracted.

Lift of Blade

Grader

The working tool (blade) is firmly linked to the chassis via hydraulic rams. When passing over irregularities in the ground, these are transmitted to the blade to a lesser extent, unless counteracted.

Lift of Blade

Road Paver

The working tool is not firmly linked to the chassis. The screed is carried by the mix (principle of the Floating Screed) and changes its position only as a result of changes in the screed planing angle. The screed moves up and down to a lesser extent than the actual irregularity.

Change in Screed Planing Angle

86

5

37

4

1 2

10 11


1. Material Hopper / Push-RollersFeed lorries dump the paving material into the material hopper at the front of the road paver. The lorry wheels make contact with the push-rollers and run on these.

2. ConveyorsWide conveyors transfer the paving material from the material hopper through the conveyor tunnel inside the machine to the augers in front of the screed.

3. TractionIn VGELE road pavers, powerful engines are installed for a high tractive effort. VGELE pavers come in tracked or wheeled versions.

4. AugersAugers fulfil the task of evenly spreading the mix in front of the screed. Augers are adjustable in width to match the width of the screed so that uniform compaction of the paving material is ensured at all times.

5. ScreedThe screed is the core of the VGELE road paver. The screed acts upon the paving material by way of its own weight and the compactive effort of its compacting systems. This results in precompaction of the mix and profiling of the placed layer.

6. Screed HeatingIn order to prevent the asphalt mix from sticking to the screed plates and the compacting elements (tamper, pressure bar(s)), electric heating is provided.

7. Adjustment of Screed Tow PointsThe tow point rams make it possible to vary the screed planing angle and hence the layer thickness via the screed arm.

8. Screed Assist / Screed FreezeDepending on the working conditions on site, pressure is applied to the hydraulic rams linked to the screed arms, or the hydraulic rams are relieved of pressure. This influences the weight of the screed and consequently also its floating function (see page 94 onwards).

1.2 Components of a Road Paver

The Machines Made by VGELERoad pavers place all kinds of bituminous materials as well as materials for the roadbase. When the mix has been dumped into the pavers material hopper by the feed lorry, conveyors transport the material in front of the screed. This is where the process of paving proper takes place. VGELE pavers stand out through their capability of producing high quality pavements, their excellent reliability as well as service-friendliness and ease of operation.

H b

h a

h = H x a

b

12 13


The floating working tool is the main difference distinguishing a road paver from other construction machinery. In other words, the layer thickness only changes as a result of changes in the screeds planing angle or changes in the height of the screed tow points. This way, irregularities in the ground are diminished when passed over, without having to intervene through a control system.

Short irregularities in the base are levelled out through the self-levelling property of the Floating Screed.

When passing over long irregularities, the height of the screed tow points changes, thus leading to a change in the layer thickness.

Depending on the screed planing angle, more or less mix is packed under the screed as the paver advances, and the layer thickness gradually changes over a longer distance.

The response of the screed to such changes depends on:

Pave speed Change in height of the screed tow points

Properties of the mix (compactability, load bearing capacity).

1.4 Theoretical Outline of the "Floating Screed Principle" without Grade and Slope Control

The following rule can be derived from the example of a paver passing over a short irregularity:

Taking into account different lengths (b) (extending over length of screed arm and depth of screed plate) for the different paver types, an average ratio of about 5 : 1 results as far as compensation of a short irregularity in the base is concerned.

Long irregularities in the base can only be levelled out by actively controlling the height of the screed tow points.

h = Height after compensation

H = Height of irregularity

a = Depth of screed plate

b = Length of screed arm

+ depth of screed plate

NOTE

The evenness of the pavement must increase with every layer placed. The magnitude of improvement depends on the quality of the layer below.

Height of Screed Tow Point

Speed Properties of Mix

1.3 The Floating Screed Principle

14 15


Tracked Paver

Crawler tracks transmit the power delivered by the high-performance engine to the ground. In contrast to wheels, crawler tracks have a larger contact area with the base, allowing them to achieve a higher tractive effort. For the tracked pavers, the power is generated where it is needed: right at the sprocket. The powerful undercarriage is ideal for use of the paver also on difficult terrain and in large pave widths up to 16m. For the two crawler tracks, separate electronic control is provided. This allows impeccable turning also of radii at a constant pave speed.

1.5 Tracked Pavers and Wheeled Pavers

VGELE pavers are available in tracked or wheeled versions. Each version offers its particular advantages.

ADVANTAGES OF THE TRACkED PAVER

High tractive effort. Universal application. Handles large pave widths. Easily pushes heavy feed lorries. Use also on a soft base.

16 17


1.5 Tracked Pavers and Wheeled Pavers

ADVANTAGES OF THE WHEELED PAVER

Travel from one job to another under its own power. Travel speed up to 20km/h also on public roads.

Ideal when frequent and quick transfer is required. Smooth running when paving asphalt wearing course. Excellent manuvrability. Front wheels are in permanent contact with the ground thanks to oscillating axle.

Wheeled Paver

Wheeled pavers display their strong points above all when it comes to frequent travels from one project to another. VGELE pavers travel at speeds up to 20km/h under their own power, so trucking is not required for job sites in the near surroundings. The wheeled VGELE pavers feature excellent manoeuvrability thanks to a turning radius of just 6.5m.

For placing high-quality surface course, smooth running of the paver is a must. The wheeled VGELE pavers optimally achieve this goal thanks to the oscillating axle and the damping effect of their rear wheels.

18 19


VISION Series

SUPER SeriesMachine Class

Type Weight Basic Maximum Maximum Width Pave Width Laydown Rate

Machine Class


Machine Class

Type Weight Basic Maximum Maximum Width Pave Width Conveying Capacity

PowerFeeder Series

15.5t 2.45m 5.8m 700 tonnes/h

14.9t 2.6m 5.8m 700 tonnes/h

Universal Class Tracked Paver VISIOn 5100-2

Wheeled PaverVISIOn 5103-2

19.4t 3m 8.6m 1,200 tonnes/h

18.5t 3m 7.8m 1,200 tonnes/h

Tracked Paver VISIOn 5200-2

Wheeled PaverVISIOn 5203-2

HigHway Class

speCial Class 17t 3m 1,200 tonnes/h

23t 3m 1,200 tonnes/h

20.8t 2.55m 6m 700 tonnes/h

23.6t 2.55m 5m 700 tonnes/h

26.6t 3m 8.5m 1,100 tonnes/h

SUPER 1800-2 with SprayJet Module

SUPER 1800-2Slope Paver

SUPER 2100-2 IPfor Paving Binder Course

speCial Class 5.9t 1.1m 3.2m 200 tonnes/h

6.1t 1.1m 3.2m 250 tonnes/h

Tracked PaverSUPER 700

Tracked PaverSUPER 800

Mini Class

20.9t 2.55m 11m 900 tonnes/h

21.9t 2.55m 13m 1,100 tonnes/h

28.7t 3m 16m 1,600 tonnes/h

Tracked PaverSUPER 1900-3



HigHway Class

8.5t 1.8m 4.2m 300 tonnes/h

8.6t 1.8m 4.2m 200 tonnes/h

9.5t 1.8m 5m 350 tonnes/h

9.5t 1.8m 4.5m 250 tonnes/h

Tracked Paver SUPER 1100-2

Wheeled PaverSUPER 1103-2



CoMpaCt Class

18.4t 2.55m 8m 600 tonnes/h

17t 2.55m 7m 600 tonnes/h

19.3t 2.55m 10m 700 tonnes/h

17.3t 2.55m 8m 700 tonnes/h





Universal Class

SUPER SeriesMachine Class


1.6 VGELE Product Overview

PowerFeederMT 3000-2

PowerFeederMT 3000-2 Offset

20 21


Maximum Pave Width (m)

1411

16

15

129 1310

SUPER Series

VISION Series

SUPER Series Special Class

SUPER Series

VISION Series

SUPER 3000-2

SUPER 2100-3

SUPER 1900-3

SUPER 1600-2

SUPER 1803-2

SUPER 1800-2

SUPER 2100-2 IP for Paving Binder Course

1.6 VGELE Product Overview 1.6.1 Paver Classification

Max

imum

Lay

dow

n Ra

te (t

onne

s/h)

100

5 2 6 3

900

500

1,300

300

1,100

700

1,500

200

7 4 1

1,000

600

1,400

400

1,200

800

1,600

SUPER 1300-2SUPER 1100-2

SUPER 800

SUPER 700

SUPER 1603-2

SUPER 1303-2

SUPER 1103-2

VISIOn 5200-2

VISIOn 5100-2

VISIOn 5203-2

VISIOn 5103-2

SUPER 1800-2 Slope Paver


22 23


1.7 Examples of Paver Applications1.7.1 Types of Paving

Paving Asphalt Tracks or Special Profiles

Extending screeds can be set up for paving a large variety of special profiles thanks to their systems for adjustment. Even positive or negative gull wing profiles (M or W profiles) can be handled when height adjustment of the extending units is combined with crown adjustment of the basic screed.

Special slipforms are available for the construction of farm tracks or railway tracks.

Asphalt can also be paved on steep banks with the aid of special slipforms, for instance on racing circuits.

Classical Application

Placing all kinds of pavement layers for roadways and paths. Pavers are available in various performance classes and combine with a variety of screed options to handle these paving jobs. Layer thickness ranges from 2cm to 40cm.

Paving on a Slope (Vertical)

Apart from construction of conventional roads with gradients (uphill or downhill), road pavers can also be used for special applications, such as paving on a slope for construction of dams, retaining walls, etc. In general, only slight conversion of the paver is required for handling jobs of this kind. For application under extreme conditions (steep slope), a special Slope Paver can be used that has undergone modification.

Paving on a Slope (Horizontal)

As an alternative to paving in a vertical direction, pavers also work in a horizontal direction. In general, such applications, too, require no more than slight conversion of the paver. Paving work like this is also often found in the field of dam or canal construction.

24 25


InLine Pave Train

The two-layer construction of asphalt pavements by hot on hot paving constitutes a particularly efficient method of building long-lasting roads. With this method, the binder course and wearing course are placed hot on hot in a single pass, thus yielding not only a perfect bond between layers but also strong interlocking. Both such two-layer pavements and conventional paving work can be realized most economically and in high quality when using InLine Pave machine technology from VGELE.

The InLine Pave train comprises three machines: a MT 3000-2 Offset material feeder, a SUPER 2100-2 IP paver for the binder course and a SUPER 1600-2 or SUPER 1800-2 for the wearing course. These machines run directly one behind the other, in a single line.

The paving process starts with the material feeder. It receives the binder and wearing course mixes supplied by feed vehicles and alternately transfers the mix either directly into the large material hopper of the paver for binder course or to the transfer module for the hopper of the paver for wearing course. The SUPER 2100-2 IP is responsible for paving a high-density binder course with high resistance to deformation. This paver is equipped with the special AB 600 High Compaction Screed in TP2 Plus version from VGELE. The third machine in the InLine Pave train is a SUPER 1600-2 or SUPER 1800-2 for paving the wearing course.

1.7 Examples of Paver Applications1.7.2 InLine Pave / SprayJet Technology


Paving a thin overlay on a spray seal or tack coat, hot on hot, is a cost-effective method of resurfacing existing roads, but it requires special machine technology.

With the SUPER 1800-2 with SprayJet Module, the existing road surface can be spread with bituminous emulsion and a new wearing course paved in a single operation. Site vehicles no longer drive over the emulsion, as it is directly overlaid with asphalt. In other words, a perfect tack coat is produced to ensure perfect bonding between the layers. Whats more, the roads round about are no longer fouled when using this method, as vehicles do not drive over the emulsion.

SprayJet technology is also ideal for placing low-noise wearing courses.

In order to preserve the noise-absorbing cavities, the mix cannot be compacted to the same degree as conventional asphalt. The pavement quality would suffer when using the conventional two-step method, as thicker layers would be needed, but this would impair the pavements durability due to the lesser compaction.

26 27


Placing Roadbase Material or Water-bound Base Course Material

Their self-levelling effect and physical advantages as compared to graders and bulldozers make pavers eminently suitable for building a crushed-stone roadbase or placing a water-bound base course.

Pavers are ideal, particularly when building long stretches of new road and for roads on which higher surface accuracy is required. Extensive and uniform basic stability is assured, especially in the lower layers, by their homogeneous compaction over the full width of the road.

1.7 Examples of Paver Applications1.7.3 Paving Materials

Paving Bituminous Material

Throughout the world, pavers are the "no. 1" machine for placing wearing courses, binder courses and bituminous base courses of asphaltic concrete or stone mastic asphalt.

Their advantages include the following features in particular: very good self-levelling properties, high and homogeneous precompaction, as well as the ability to heat all machine parts in contact with the material.

Paving PCC and RCC

Pavers can even place materials such as PCC (Paver Compacted Concrete) and RCC (Roller Compacted Concrete) if the specifications for the PCC and RCC formulation are adhered to precisely.

PCC and RCC are frequently used, especially in north America and Asia, but they are also becoming more widespread in Europe, too, for instance for industrial areas.

28 29


2 Screed 29

2.1 General Differences between Screeds ................................................................ 302.2 Extending Screeds ................................................................................................ 32 2.2.1 Components of the Extending Screed ........................................................................... 32 2.2.2 Compacting Systems Installed in Extending Screeds ................................................. 34 2.2.3 Extending Screeds and Bolt-on Extensions .................................................................. 36 2.2.4 Set-Up of the Extending Screed ....................................................................................... 38 2.2.5 Mechanical Design and Maintenance of the Telescoping System .......................... 482.3 Fixed-Width Screeds ............................................................................................. 50 2.3.1 Components of the Fixed-Width Screed ........................................................................ 50 2.3.2 Compacting Systems Installed in Fixed-Width Screeds ............................................. 52 2.3.3 Fixed-Width Screeds and Bolt-on Extensions ............................................................... 54 2.3.4 Set-Up of the Fixed-Width Screed ................................................................................... 602.4 Screeds for the VISION Series of Pavers .............................................................. 62 2.4.1 VF Extending Screed (with Front-Mounted Extensions) ............................................ 62 2.4.2 VR Extending Screed (with Rear-Mounted Extensions) ............................................. 64 2.4.3 Main Applications ................................................................................................................ 662.5 Special Screed: AB 600 High Compaction Screed in TP2 Plus Version ............ 682.6 Set-Up .................................................................................................................... 70 2.6.1 Tamper ................................................................................................................................... 70 2.6.2 Pressure Bar(s) ...................................................................................................................... 71 2.6.3 Tamper Shield ....................................................................................................................... 722.7 Side Plates .............................................................................................................. 73 2.7.1 Mechanical-hydraulic Side Plate ...................................................................................... 73 2.7.1.1 Hydraulic Side Plate from VGELE ................................................................................... 74 2.7.1.2 Standard Side Plate from VGELE ................................................................................... 76 2.7.2 Bevel Irons ............................................................................................................................. 772.8 Screed Heating ...................................................................................................... 782.9 Screed Maintenance ............................................................................................. 80 2.9.1 Daily Maintenance ............................................................................................................... 80 2.9.2 Weekly Maintenance .......................................................................................................... 82

30 31

VGELE BOOkLET On PAVInG 2. SCREED

2.1 General Differences between Screeds

The screed is the true heart of the VGELE paving system. It accommodates the compacting systems which provide high density and durable results. VGELE screeds are available in two versions: as Fixed-Width Screeds (SB) or Extending Screeds (AB).

The screed, the road pavers working tool, fulfils the function of uniformly compacting the paving material across the entire pave width and producing a close-textured and level surface.

The screeds compacting systems must precompact the mix to the greatest possible extent. This minimizes the influence of layer thickness on the amount of subsequent compaction by rolling when bringing about the pavements final density. For precompaction, different compacting systems are available.

The abbreviations for the compacting systems are as follows: T = Tamper (an eccentric shaft causes the tamper bar to move up and down).

V = Vibrators (vibrations are generated by an eccentric shaft acting on the screed plates at right angles to the direction of motion).

P = Pressure Bar(s) (the pressure bar(s) are hydraulically pressed onto the mix at a frequency of 68 Hz (approx.) and a maximum pressure of 130 bar).

P1 = Screed equipped with 1 Pressure Bar

P2 = Screed equipped with 2 Pressure Bars

Extending Screed

Fixed-Width Screed

Variable screed, customarily used today. Limited pave widths. Vast range of uses.

Ideal for all manner of jobs requiring variability and adaptability.

Large pave widths. Hydraulic extending units enlarge

the range of uses.

Highly accurate paving true to line and level. Suitable for high compaction, e.g. when

placing water-bound base, RCC and PCC.

32 33


2.2 Extending Screeds2.2.1 Components of the Extending Screed

Screeds Hydraulically Extending Unit

Torque Restraint System

Single-Tube Telescoping System Hydraulic Ram for Screed Width Control

Tamper with Heating Rod

Eccentric Vibrators

Screed Body

Monitoring Unit for Heating Rods

Screed Plate with Heating Element

34 35


2.2 Extending Screeds2.2.2 Compacting Systems Installed in Extending Screeds

V = VibratorsInstalled in:

AB 200 Extending Screed AB 340 Extending Screed

Recommended for: Materials which are easy to compact.

TP1 = Tamper and 1 Pressure BarInstalled in:

AB 500 Extending Screed AB 600 Extending Screed

Recommended for: All conventional mixes. Precompaction by a screed in TP1 version

is higher than by a TV screed, but lower than by a screed in TP2 version.

Less extra compaction by rolling required.

TV = Tamper and VibratorsInstalled in:

AB 200 Extending Screed AB 340 Extending Screed AB 500 Extending Screed AB 600 Extending Screed

Recommended for: All conventional mixes. Use with wheeled pavers due to the lower

weight as compared to screeds in TP1 or TP2 versions.

Materials which are easy to compact.

TP2 / TP2 Plus = Tamper and 2 Pressure BarsInstalled in:

AB 500 Extending Screed (TP2) AB 600 Extending Screed (TP2/TP2 Plus)

Recommended for: All conventional mixes. The screed in TP2 version achieves high

precompaction when placing thick layers. The screed in TP2 Plus version is used above

all for base and binder courses due to its high compacting effort.

Mixes which are difficult to compact on account of their grain shapes and consistency.

Less extra compaction by rolling required. Jobs which do not allow subsequent

compaction by rolling.

36 37


AB 200 AB 340

AB 600AB 500

2.2 Extending Screeds2.2.3 Extending Screeds and Bolt-on Extensions

For all VGELE screeds, bolt-on extensions are available. The VGELE system of bolt-on extensions makes it possible to easily and sturdily build up screeds to any pave width desired. Even when paving in large widths, VGELE screeds work with highest precision and achieve superb degrees of uniform density right up to the pavement edges.

When fitting bolt-on extensions, care must be taken to ensure that the bottom edge of the screed plate is flush with the adjacent units, otherwise a step may be produced in the pavement or the screed planing angle may change. During the paving process, this can have a negative effect on precompaction, surface structure and floating behaviour of the screed.

1.225m 1.225m2.55m5m

2 x 0.25m

5.5m

2 x 0.75m

6.5m

2 x 0.75m + 2 x 0.25m

7m

2 x 1.25m

7.5m

4 x 0.75m

8m

4 x 0.75m + 2 x 0.25m

8.5m

0.45m1.1m

2m

2 x 0.35m

2.7m

2 x 0.6m

3.2m

0.45m

0.8m3.4m

2 x 0.4m

4.2m

2 x 0.55m4.5m

1.8m

2 x 0.80m

5m

2 x 0.25m3.9m

0.8m

1.5m3m6m

2 x 0.25m

6.5m

2 x 0.75m

7.5m

2 x 0.75m + 2 x 0.25m

8m

2 x 1.25m

8.5m

4 x 0.75m

9m

4 x 0.75m + 2 x 0.25m

1.5m

9.5m

55

3

6

4

7

38 39


Setting Up the Screed: Prerequisites

1. Clearance between sliding blocks and sliding rail has been set and checked (see page 48).

2. Height adjustment: Adjusting spindles have been set and checked (see pages 42 onwards).

3. Screed has been raised and laid down on locking bolts.

4. Both tow point rams are in their lowest position.

5. Crown has been set to 0%.

6. Clamping screw for height adjustment is released.

7. Height adjustment of the extending screed has been set to 0 on the scale.

2.2 Extending Screeds2.2.4 Set-Up of the Extending Screed

1 2 3

4

40 41


NOTE

Retighten the clamping screw for height adjustment after setting the screed planing angle. Then check the setting again.

Setting the Screed Planing Angle: Outer Extending Screed Retract the screed completely.

Hold the ruler [4] under the screed plates in the area of the outer adjusting spindles.

Set the extending unit via the mechanism for height adjustment so that the ruler makes contact with the three points [1], [2] and [3].

Measure the clearance. About 30mm behind the rear edge of the tamper, there must be a gap of roughly 1mm between the ruler and the screed plate.

Unscrew the chains on the adjusting spindles.

Make the setting at the front adjusting spindle with a suitable tool.

Measure the clearance and repeat the procedure if necessary.

Setting the Screed Planing Angle: Inner Extending Screed Extend the screed until the adjusting spindles are located under the sliding blocks.

Hold the ruler [4] under the screed plates in the area of the inner adjusting spindles.

Set the extending unit via the mechanism for height adjustment so that the ruler makes contact with the three points [1], [2] and [3].

Measure the clearance. About 30mm behind the rear edge of the tamper, there must be a gap of roughly 1mm between the ruler and the screed plate.

Unscrew the chains on the adjusting spindles.

Make the setting at the front adjusting spindle with a suitable tool.

Measure the clearance and repeat the procedure if necessary.


13

2

5

4

42 43



Height Adjustment, Adjusting Spindle

Setting the Adjusting Spindle Without unscrewing the locking bolts, check the slack of the threaded bush [1].

Procedure: Lower the screed with extending units onto wooden blocks.

Open the chains [2] by means of the shackle type connector.

Turn the adjusting spindles [3] down to ensure that their face end [5] rests completely on the flange surface of the screed frame.

Remove the hexagon socket screw [1] from the flange.

Tighten the threaded bush [4] with a suitable tool.

Back off the threaded bush [4] with a 45 turn until the hole of the locking screw is free.

Tighten down the hexagon socket screw [1].

NOTE

Always set all four spindles for each extending screed.

44 45



Preparation Support the screed on large wooden

blocks or pallets to compensate for any unevenness of the ground.

Flange surfaces must be clean, i.e. free from asphalt.

Fitting the Braces The frames of the screeds extending unit

and of the bolt-on extension must be joined. Then fit the braces stabilizing the bolt-on

extensions. These braces must be adjusted so that a light downwards pressure is exerted onto the extension.

Height Adjustment of the Bolt-on Extension

The height of the extending unit and bolt-on extension in relation to one another is adjusted via the eccentric bolts so that the trailing edges of the screed plates are flush while the leading edges are between 0.5 and 1mm higher.

Easy and Fast Attachment with Quick-fitting Aid

The bevelled quick-fitting aid makes it possible to raise a bolt-on extension without tightening down the screws. This allows an extension to be fitted even on an uneven base.

TIP!

TIP!TIP!

Before mounting a bolt-on extension, the tamper shafts of both the screeds extending unit and the bolt-on extension must be set so that the arrow on the coupling points to the gap in the gearwheel (see photo).

The pressure is correct if the brace can be turned slightly. If it cannot, the pressure is too high.

The front and rear eccentric bolts must be set to zero position (uppermost position). This is important later on for aligning the extending unit with the basic screed.

1mm (maximum)0mm

46 47


Connecting Systems now connect the heating (upper photo). Then connect the tamper shaft to the

Haldex coupling (middle photo).

When mounting bolt-on extensions to VGELE High Compaction Screeds, two extra steps need to be carried out (see right).

The following steps only need to be carried out when fitting bolt-on extensions to VGELE High Compaction Screeds with 1 or 2 pressure bars (TP1 or TP2).

Joining the Pressure Bars Joining of pressure bar 1 (and 2,

if equipped) of the bolt-on extension with those of the basic screed using spring washers and a spacer block.

The bottom edges of the pressure bars must also feel flush (see photo).

Then check the pressure bars for smooth and free movement.

Vent the pressure bar(s) at specified intervals.

Special tools for joining the pressure bars: The tools required are a standard ratchet, a hexagon adaptor and an Allan key.

Connecting Hydraulic Piping Connect the hydraulic piping, e.g. to the

pressure bar.

All further steps are identical for all screed types.

Final Assembly Finally, the tamper shield, the auger shafts

and the footboard with cover plate are to be fitted.


48 49


Internal Guide Tubes The guide tubes must be regularly lubricated with silicone grease. Contact with sharp-edged objects (blades, etc.) must be avoided. Ensure a perfect seal between the individual tubes. If possible, the underside of the tubes should not be allowed to come into

contact with asphalt (e.g. when rapidly extending and retracting the screed).

Telescoping Tubes The telescoping tubes must be regularly lubricated with silicone grease. Contact with sharp-edged objects (blades, etc.) must be avoided. Ensure a perfect seal between the individual tubes. If possible, the underside of the tubes should not be allowed to come

into contact with asphalt (e.g. when rapidly extending and retracting the screed).

Torque Restraint System The sliding blocks and the rail of the torque

restraint system must be greased regularly. The sliding blocks must be set so that

they make contact without play during operation.

Worn sliding blocks must be replaced.

Others Particularly the leading edge of the screed and the tamper

area must be washed down with cleaning agent every morning and evening. Let the tamper run at low speed so that the cold material can drip onto a suitable substrate.

Ensure that the pressure bars in particular can move freely.

2.2 Extending Screeds2.2.5 Mechanical Design and Maintenance of the Telescoping System

50 51


Basic ScreedTamper with Heating Rod

Bolt-on Extension

Eccentric Vibrators

Pressure Bars with Heating Rods

Screed Plate with Heating Element

2.3 Fixed-Width Screeds2.3.1 Components of the Fixed-Width Screed

52 53


2.3 Fixed-Width Screeds2.3.2 Compacting Systems Installed in Fixed-Width Screeds

TV = Tamper and VibratorsInstalled in:

SB 250 Fixed-Width Screed SB 300 Fixed-Width Screed

Recommended for: All conventional mixes. Materials which are easy to compact

or thinner pavement layers. Jobs where paving can be done in a largely

constant width and where large radii are involved.

TP2 = Tamper and 2 Pressure BarsInstalled in:

SB 250 Fixed-Width Screed (and Hydraulic Bolt-on Extensions)


Recommended for: All conventional mixes. A screed in TP2 version achieves a high

precompaction even of thick pavement layers. Mixes which are difficult to compact on

account of their grain shape and consistency. Jobs where paving can be done in a largely


Less effort required for subsequent compaction by rolling.

TP1 = Tamper and 1 Pressure BarInstalled in:



Recommended for: All conventional mixes. Precompaction by a screed in TP1 version

is higher than by a TV screed, but lower than by a screed in TP2 version.

Jobs where paving can be done in a largely constant width and where large radii are involved.

Less effort required for subsequent compaction by rolling.

TVP2 = Tamper, Vibrators and 2 Pressure BarsInstalled in:

SB 250 Fixed-Width Screed SB 300 Fixed-Width Screed SB 250 B Fixed-Width Screed

Recommended for: Jobs where paving can be done in a largely


SB 250, SB 300: All conventional mixes. SB 250 B: For paving PCC, as this type of job

does not include subsequent compaction by rolling.

54 55


2.3 Fixed-Width Screeds2.3.3 Fixed-Width Screeds and Bolt-on Extensions

As a general rule, bolt-on extensions should be fitted symmetrically on both sides of the screed wherever possible. The advantage of a Fixed-Width Screed is a deeper screed plate of 500mm compared to a screed plate of 250mm found on Extending Screeds. This has a positive effect upon the screeds floating behaviour.

Moreover, the leading edge of the Fixed-Width Screed forms a single line over the entire pave width and different planing angles do not leave marks in the pavement. Fixed-Width Screeds are capable of handling considerably larger pave widths than Extending Screeds, albeit with restrictions as regards the screeds variability. As a result, Fixed-Width Screeds are particularly suited to paving long sections with a large, unchanging pave width.

Hydraulic bolt-on extensions allow infinite variation of pave width also for Fixed-Width Screeds.

NOTE

The hydraulic bolt-on extensions (0.75m) can only be fitted to mechanical extensions with a width of 1m or more. The basic screed must be built up by at least 1.5m on both sides in order to mount the hydraulic bolt-on extensions.

56 57


Basic Screed 3m

1.5m 1.5m 0.25m

6m 6.5m

1.5m 1.5m 0.25m0.5m

0.5m

7m 7.5m

1.5m 1.5m 0.25m1m 1m

8m 8.5m

1.5m 1.5m1m 1.5m0.5m

9m 9m

1.5m 1.5m1m 1.5m 0.5m0.25m0.5m

9.5m 10m

1.5m 1.5m 1m1.5m0.25m0.5m

1.5m

10.5m 11m

1.5m 1.5m 1m1.5m0.25m 1.5m1m 0.5m

11.5m 12m

1.5m 1.5m 1.5m1.5m 0.25m1.5m1.5m

12m 12.5m

1.5m 1.5m 1.5m 1.5m 1.5m1.5m 1.5m1m

0.5m

15m 15m

1.5m 1.5m 1.5m1.5m 1.5m1.5m

13m 13.5m

0.5m 0.5m

0.25m

1.5m 1.5m 1.5m1.5m 1.5m1.5m 1m1m

14m 14.5m

0.25m

1.5m 1.5m 1.5m1.5m 1.5m1.5m 1.5m1.5m

0.5m0.25m

15.5m 16m

Top View Building up a SB 300 Fixed-Width Screed to its maximum pave width Horizontal Bracing


58 59



Basic Screed 3m

1.5m

0.25m

0.25m0.5m

6m 6.5m

1.5m

1.5m

7m 7.5m

1.5m

0.5m

0.25m

1.5m

8m 8.5 m

1.5m

1.5m

9m 9m

1.5m

0.5m

1.5m

9.5m 10m

1.5m

0.25m

1.5m

10.5m 11m

1.5m

1.5m

1.5m

0.5m0.25m

1.5m1.5m

1m

0.5m

1m

1.5m

1m

Basic Screed 3m

1.5m

0.75m

11.5m 12m

1.5m

1.5m

12m 12.5m

1.5m

0.25m

1.5m

13m 13.5m

1.5m

1.5m

14m 14.5m

1.5m

1.5m

15m 15m

1.5m

1.5m

15.5m 16m

1.5m

1.5m

1.5m

1.5m1.5m

1.5m 1.5m1.5m

0.5m

1.5m 1m1.5m1.5m

0.5m

1.5m 1.5m1.5m1.5m

1.5m1.5m

1.5m1.5m1.5m 1.5m

1.5m1.5m 1.5m1.5m

1m0.25m

1m 1m 1m

0.75m

0.5m

0.5m0.25m

1m

1m

Rear View Building up a SB 300 Fixed-Width Screed to its maximum pave width Vertical Bracing

60 61


2.3 Fixed-Width Screeds2.3.4 Set-Up of the Fixed-Width Screed

+0mm+0.5mm+0mm+0.5mm

Bolt-on extensions are fitted to enlarge the screeds width. The trailing edges of the screed plates must be flush across the entire pave width. The leading edges of the screed plates (each bolt-on extension) should be set higher towards the outside by roughly 0.5mm.

In order to prevent the bolt-on extensions from bending towards the rear as a result of the pressure exerted by the mix, horizontal braces must be fitted.

To compensate the uplift at the outer edges of the screed, the screed should sag slightly when raised. The magnitude of this sag depends on the pave width. The sag can be adjusted by way of the braces over the screeds basic unit.

Horizontal braces should be fitted in such a way that the trailing edges of the screed plates are flush.

Top View

Basic Screed 1.5m 1.5m 1.5m1.5m 1.5m 1.5m

Rear View

Sag

Recommendation

Pave Width Sag

16m 5.5cm (approx.)

12m 3.5cm (approx.)

up to 10.5m 2cm (approx.)

ATTENTION!

The values indicated in the table are approximate values for set-up of the screed. When paving, the transverse evenness of the pavement must be checked and the braces re-adjusted, if necessary.

62 63


Pave Widths 3.05m to 7.75m (dependent on type of tractor unit)Basic Width 3.05mInfinitely Variable Range 3.05 up to 5.95m

Larger Width Bolt-on Extensions 30cm 60cm

Crown AdjustmentHydraulic -2.5% to +5% M, W or parabolic profiles possible

Transverse SlopeExtending Units up to 10%

Berm Profiles 30cm, 45cm and 60cm available

Compacting SystemScreed Version VVibrators (V) eccentric vibrators,

frequency up to 50 Hz

Screed Heating screed plates heated electrically by heating rods

Dimensions (Transport, Basic Screed) Width 3.05mDepth 1.17mWeight 3.72t

2.4 Screeds for the VISION Series of Pavers2.4.1 VF Extending Screed (with Front-Mounted Extensions)

Robust and smooth guide system for precise operation at all widths.

Basic width 3.05m.

Infinitely variable range 3.05m up to 5.95m.

Maximum pave width 7.75m.

Suitable for many screed profiles with crown and sloping extensions. Berm is available as an option.

Sloping extension up to 10%.

Innovative electric screed heating.

Easy-to-use ErgoPlus operating system.

Compact design allows for great visibility in all areas.

Ideal tool for multivariable width applications and mainline paving.

3.05m

5.95m

6.55m

7.15m

7.75m

64 65


Pave Widths 3.05m to 8.6m (dependent on type of tractor unit)Basic Width 3.05mInfinitely Variable Range 3.05m up to 6m

Larger WidthsBolt-on Extensions 65cm

Crown AdjustmentHydraulic -2.5% to +5% M, W or parabolic profiles possible

Transverse SlopeExtending Units up to 10%

Compacting SystemScreed Version VVibrators (V) eccentric vibrators, frequency

up to 50 Hz

Screed Heating screed plates heated electrically by heating rods

Dimensions (Transport, Basic Screed) Width 3.05mDepth 1.24mWeight 3.75t

Large dimensioned, sturdy telescoping tubes featuring high-precision operation. They provide for excellent stability of the screed, ensuring great paving results.

The telescoping tubes of the screed are located in a high position, thus avoiding any contact with the mix.

Even with the screed set to its maximum width, the telescoping tubes are extended by no more than half, which provides for zero flexing.

Deep screed plate design provides excellent floatation.

The attachment of the telescoping tubes, the support of the guide tubes and the torque restraint system make up a sturdy 3-point suspension, absorbing the forces exerted on the screed while paving and guaranteeing smooth width control of the extensions.

Basic width 3.05m.

Infinitely variable range 3.05m up to 6m.

Maximum pave width 8.6m.

Sloping extension up to 10%.

Sturdy telescoping system with 3-point suspension.

Innovative electric screed heating system.

Easy-to-use ErgoPlus operating system.

2.4 Screeds for the VISION Series of Pavers2.4.2 VR Extending Screed (with Rear-Mounted Extensions)

3.05m

6m

2 x 0.65m

4 x 0.65m

7.3m

8.6m

66 67


2.4 Screeds for the VISION Series of Pavers2.4.3 Main Applications

Screed with Front-Mounted Extensions for Multivariable Width Applications

Working at high pave speeds with varying pave widths requires a screed that can always be relied on to deliver precise results. The VF 600 from VGELE is just such a system.

Several constructive features greatly support fast and precise retraction of the screed. For instance, the material offers virtually no resistance at the bevelled leading edges of the extensions, and blockades and obstacles are avoided. An additional advantage is that the side plates of a front-mounted screed are only about half as long as those of a rear-mounted screed, permitting particularly precise paving, working close up to obstacles. This, in turn, reduces the subsequent need for shovelling. Its variability is also evidenced in the wide range of possible profiles.

All features combine to make the VF 600 equally suitable for building intersections on highways and for surfacing country roads with multiple obstructions. It is above all invaluable when tackling multivariable applications with many obstacles which require frequent changes in pave width, such as parking lots with several islands, light poles and storm sewers or residential and city streets with gas and water mains.

Screed with Rear-Mounted Extensions for Multi-Lane Paving

When paving across large widths, absolute accuracy of line and level is a crucial criterion for prime-quality results, regardless of the pave width and layer thickness involved. The VGELE VR 600 Extending Screed boasts impressive abilities in this respect: its basic width is 3.05m and it can be extended hydraulically up to 6m nearly twice the basic width. With bolt-on extensions fitted, the screed builds up to a maximum width of 8.6m and is equipped with vibration across the full pave width. The quick-fitting system allows the 0.65m wide bolt-on extensions to be mounted very easily and quickly.

Based on its outstanding overall technical concept, the VR 600 is the perfect choice for medium and large-scale road construction projects. When it comes to paving asphalt layers across multiple lanes, the new screed also yields substantial advantages over single-lane paving as it avoids joints, the weak points in every asphalt pavement.

68 69


Return Pipe

Pulse Generator Pressure BarTank

2.5 Special Screed: AB 600 High Compaction Screed in TP2 Plus Version

In recent years, the AB 600 in TP2 Plus version has been developed further and perfected to meet the special requirements of "hot on hot" paving. On an InLine Pave contract, it achieves an extraodinarily high degree of precompaction. Depending on the paving material used, the resultant compaction comes very close to the final density.

The AB 600 Extending Screed in TP2 Plus Version at a Glance Uses: for "hot on hot" paving of binder and base courses, as well as thick roadbase packages. Maximum pave width 8.5m. Supplementary weight for additional compaction. Innovative tamper geometry: modified tamper shield so that material is drawn under the

screed more effectively. Variable tamper speed up to 1,800 rpm. Special tamper stroke settings 4, 7 or 9mm. 2 pressure bars with infinitely variable pressure from 40 to 120 bar.

The pressure bars P1 and P2 are the last elements in the process of compaction as a whole. Logically, they are located in the rear area of VGELE HPC screeds. Only in this location can the highest possible compactive effort be achieved, as the mix is prevented from yielding to the front. nor can it yield to the sides where it is confined by the screeds end plates.

A change from high compaction to standard compaction and vice versa can easily be made from the paver operators console. This allows use of the screed for most varied applications.

The element at the beginning of the process of VGELE High Compaction is the pulse generator as part of the pulsed flow hydraulics. It generates high-frequency pressure pulses. The pressure bar(s), in contrast to the beating tamper bar, remain in permanent contact with the mix, thus forcing the mix down for a prolonged period of time.

Thanks to the high density achieved by the pressure bar(s), fewer passes are required for subsequent compaction by rolling.

High precompaction is essential for perfectly building up a pavement in layers and for a pavement profile true to line and level.

When paving layers varying in thickness, VGELE High Compaction Technology ensures that, although an identical pressure is applied across the screed width, the pressure bar(s) are forced down to varying depths. This way, an absolutely uniform density is produced.

For each compacting system installed in a VGELE HPC screed, separate control is provided.

Fine control of the pressure for pressure bar(s) allows use of VGELE High Compaction Technology for paving surface course, too.

Key: T = Tamper P1 = Pressure Bar 1 P2 = Pressure Bar 2

12

4

6

6

43

58

7

1

2

70 71


The tamper must be set to an identical stroke length across the entire pave width. The setting can be changed by simply turning the eccentric bush on the shaft driving the tamper bar. The driving shaft is accessible from behind, so that this can easily be done between job site sections. Adjusting the lower reversal point of the tamper bar, however, takes more time. First, the tamper shields need demounting. Then remove the screws on all shaft brackets. After loosening the locking nut (2), the tamper bar can be adjusted via bolt (1). The height to be set depends on the tamper stroke selected.

Eccentric Shaft at Lower Reversal Point

Screed PlateBevelled Edgeof Screed Plate

1mm at Stroke Length of 4mm

Tamper

Screed Plate

Tamper Stroke 2mm

Tamper Stroke 4mm

Tamper Stroke 7mm

Bevelled Edge of Screed Plate



0mm

Screed Plate

1mm

Screed Plate

2.5mm

Tamper Stroke 2mm The tamper bar at the lower reversal point is flush with the bevelled edge of the screed plate.

Tamper Stroke 4mm The tamper bar at the lower reversal point is 1mm lower (maximum) than the bevelled edge of the screed plate.

Tamper Stroke 7mm The tamper bar at the lower reversal point is 2.5mm lower than the bevelled edge of the screed plate.

2.6 Set-Up2.6.1 Tamper

2.6 Set-Up2.6.2 Pressure Bar(s)

0.5 - 1mmScreed PlatePressure Bar4mm

59.5mm

0.5 - 1mm

1. Unscrew the nut (2) with anti-twist device (3) on the hydraulic ram (1) for the pressure bar.

2. Turn the hydraulic ram (1) to adjust the height of the pressure bar. The clearance (7) between pressure bar and bottom edge of the screed plate should be at least 4mm.

3. Check that the hydraulic ram for the pressure bar makes contact with metal plate (5) when retracted.

4. Set pre-tension of spring (6) to 5.5mm via nut (4) to yield a distance (8) of 59.5mm.

5. Resecure the hydraulic ram (3) for the pressure bar.

TIP!

At a stroke length of 2mm, the tamper bar should be flush with the screed plate (check with your hand).

65

4

32

1

72 73


2.6 Set-Up2.6.3 Tamper Shield

The tamper (3) must be set so that it rests on the wear strip (1) across the full width. Then adjust the spring steel bar (2) on the tamper shield by means of screw (4) from the rear of the screed until a gap of 0.5 - 1mm is obtained between tamper bar and the spring steel bar.

Release screws (6) and fit various small shims (5) to align the tamper shield. With the tamper shield correctly aligned, the spring steel bar (2) is at least parallel with the tamper or preferably inclined slightly to the front.

Check and if necessary correct the clearance between tamper and spring steel bar.

0mm

0.5 - 1mm

2.7 Side Plates2.7.1 Mechanical-hydraulic Side Plate

Adjusting the height of the screeds side plates is a frequently used function during the paving process. As a user, you know from experience that this function is often needed when paving along high or low kerbs, for instance, or along gutters.

How side plates help ensure a perfect pavement quality They prevent the mix spreading sideways while paving. They produce perfect longitudinal joints or pavement edges. They provide for optimal compaction in the pavements lateral areas.

74 75


Side plates hydraulically adjustable in height are an option for the AB 500 and AB 600 Extending Screeds. They provide for even more operating comfort. In contrast to mechanical adjustment by spindle equipped as standard, the hydraulic side plate is adjusted conveniently at the flip of a switch. For height adjustment, two hydraulic rams are installed on each side plate.

A VGELE paver equipped with hydraulic side plates.

The side plate of the screed is raised or lowered simply by operating the tumbler switch.

The advantages of a hydraulic side plate become evident if the hydraulic ram for height adjustment has been extended completely by mistake.

If any unevenness is encountered in the base (as shown here by the piece of timber), the pressure in the hydraulic ram increases.

As soon as it reaches 15 bar, a valve opens retracting the hydraulic ram. This prevents the screed from getting blocked. The screed keeps floating.

2.7 Side Plates2.7.1.1 Hydraulic Side Plate from VGELE

76 77


The chain holder should be roughly in the middle and the

chain must have sufficient play. In this way, the screed can

float without hindrance resulting in a perfect pavement.

When using a side plate provided as standard on VGELE screeds, care must be taken that the chain holder is not set too low. The chain must have sufficient play. This is important as otherwise the screed cannot float.

Please remember:Floating of the screed means that the thickness of the layer to be paved is determined merely by the screed planing angle and the height of the screeds tow point. This way, irregularities in the pavement are avoided without active control.

2.7 Side Plates2.7.2 Bevel Irons

Bevel irons shape and compact the edges of the pavement. They are available with a bevel edge of 45, 52 and 60. Their size depends on the thickness of the layer to be paved.A heating rod can be installed as an option to improve the sliding properties of the bevel iron.

Layer Thickness

Angle

45 (old) 52 (current) 60 (old)

4 - 6cm

6 - 12cm

12 - 18cm

TIP!

Side plate skis and bevel irons from VGELE fit both the hydraulic side plates and the ones provided as standard.

2.7 Side Plates2.7.1.2 Standard Side Plate from VGELE

1 5

6

7

4

2

3

78 79


For the dash 2 machines, a monitoring unit for screed

heating is available as an optional extra. This feature

monitors each single heating rod for proper function

and indicates any fault without delay.

If one of the green indicator lamps goes out for a longer

period of time, this means that the heating rod is defective.

2.8 Screed Heating

All screed components in contact with the hot mix should be heated to approx. 90 C before starting work.

It is recommended to protect the screed against excessive loss of heat to the surroundings so that the heating power can be utilized effectively.

This is achieved by lowering the screed until it is about 5cm above the ground to minimize the cooling effect of the wind.

In the morning, it is ready for operation after about 30 minutes. Then lay the screed on the hot mix and pave the first 2 - 3m. now wait roughly 5 minutes so that the screed is uniformly heated by the mix.

Asphalt may stick to the tamper bar, screed plates or pressure bar(s) if the screed temperature is too low. This can lead to the formation of strips and an irregular surface texture.

The floating behaviour of the screed may vary before it reaches its operating temperature, with the result that layer thickness may also vary and deviate from that required.

1 Engine

2 Control Desk

3 Control Box / Fuse Box

4 Distributor Box

5 Generator

6 Tamper with Heating Rod

7 Screed Plate with 2 Heating Rods

TIP! ADVANTAGE

Directly after switching on the screed heating, correct operation of the heating rods can be checked by cautiously touching the tamper bar, screed plates and pressure bar(s).

Since failure of a heating rod is detected immediately, it can be replaced without delay.

21

80 81


2.9 Screed Maintenance2.9.1 Daily Maintenance

The screed is the tool used by the screed operator. Like every other tool, the screed must always be serviced and checked before it is used.

Among other things, this includes daily visual inspection for defects.

The locking screws of the mechanism for height adjustment (1) must be tested to ensure they function correctly and are secured with lock nuts.

The clearance of the torque restraint system (2) and extending screeds must be checked regularly!

The hot screed must be washed down with cleaning agent before and after use. Tamper and vibrators, conveyors and augers should run at low speed during this time. The "dash 2" machines have a special cleaning mode for this purpose.

The telescoping tubes and all internal guide tubes must be coated with silicone grease to prevent asphalt sticking to them.

Always coat the sliding blocks and the mechanism for crown adjustment with copper paste.

82 83


The screed bearings should be greased every 50 hours of operation. This is indicated by self-adhesive pictograms on all screeds. Only use high-temperature grease (resistant to temperatures of up to 200 C). Do not apply too much grease to the bearings!

NOTE

Although lube points are provided, the bearings of the vibrator shafts on the AB 200 TV are maintenance-free and therefore do not require grease. Depending on the screed type concerned, the grease nipples are located either directly on the bearing housing (AB 200 screeds, fixed-width (SB) screeds) or on the outer frame from where they are connected to the bearing housings via hoses (AB 500, AB 600 screeds).

2.9 Screed Maintenance2.9.2 Weekly Maintenance

Greasing the bearings for tamper and vibrators Example: tamper on the AB 500 Extending Screed

Example: tamper on the AB 200 Extending Screed

Tamper lube point on the right-hand side of the basic screed.

Tamper lube point on the right-hand extending unit.

84 85


3 Parameters Influencing the Paving Process 85

3.1 General ................................................................................................................... 863.2 Paving Material ..................................................................................................... 883.3 Paving Parameters ................................................................................................ 893.4 Paver Set-Up .......................................................................................................... 893.5 Relationship Between Tamper Speed and Pave Speed .................................... 923.6 Recommended Settings for the Compacting Systems ..................................... 933.7 Functions of the Hydraulic Rams for Raising / Lowering the Screed .............. 94 3.7.1 Screed Float ........................................................................................................................... 95 3.7.2 Screed Assist ......................................................................................................................... 95 3.7.3 Screed Freeze ........................................................................................................................ 95

86 87

VGELE BOOkLET On PAVInG 3. PARAMETERS InFLUEnCInG THE PAVInG PROCESS

The screed generally floats during the paving process. In other words, the screed changes its position with every change in the balance of forces, for instance due to greater resistance from the paving material, etc.

As this is undesirable when paving true to line and level with maximum accuracy, the parameters which may change when paving asphalt must be known so that they can be controlled and kept constant.

This naturally cannot be achieved 100% in practice. However, it is extremely important for the user to be aware of all the related conditions in order to produce a high quality pavement.

The various influencing parameters and their effect are explained below under the headings "Paving Material", "Paving Parameters" and "Paver Set-up".

3.1 General

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3.2 Paving Material 3.3 Paving Parameters

3.4 Paver Set-Up

Mix Temperature The mix temperature should be constant and high enough to prevent

the mix from cooling before it is laid. Paving material that has cooled is harder to compact. The load bearing capacity of the mix, too, depends on its temperature. Feeding the paver with mix must be planned so as to ensure an optimum

temperature for paving.

Grain Size The maximum grain size should not exceed 1/3 of the layer thickness,

otherwise the tamper will act directly on the underlying aggregate and shatter the grains.

Stiffness / Load Bearing Capacity The composition of the mix should remain constant throughout the

paving job.

Properties of the Mix Properties of the mix have an influence on the screeds floating behaviour. Paving materials with a high bearing capacity confront the screed

with a higher resistance than materials of poor bearing capacity. Conveying and compacting systems can be optimally set up to match

the type of mix.

Layer Thickness The larger the layer thickness, the larger the screed planing angle.

Pave Width The floating behaviour of the screed changes in accordance

with the pave width.

Paver Stop The longer the paver stops, the greater the irregularity to be expected

in a longitudinal direction.

Ambient Conditions Ambient conditions, such as temperature, can influence the mix

and change the floating behaviour of the screed.

Head of Mix in Front of the Screed If there is too large a head of mix in front of the screed, the mix may cool, thus

having an adverse effect on both precompaction and the screeds floating behaviour.

A constant head of mix in front of the screed is a precondition for perfect floating of the screed.

The thicker the layer, the greater is the upward force exerted on the screed. Proportional control of conveyors and augers provides for an optimal head

of mix in front of the screed.

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Pave Speed The pave speed determines the impact of the compacting systems on

the pavement. Pave speed and head of mix in front of the screed must be well adapted

to each other. When paving at a high speed, large quantities of paving material are

consumed, which requires good job site logistics for supplying the paver with mix.

The pave speed must be selected so as to obtain as constant a supply of mix from the feed lorries as possible.

As the pave speed has a major influence on precompaction, it should be set so that the positive screed planing angle is not too large, as this would promote irregularities. The pave speed should, therefore, be set to a value ensuring good precompaction with the screed floating on the mix at a small planing angle.

Vibration Frequency When paving thick layers, the vibration frequency has little influence on

compaction. Vibration is far more important when paving wearing course, as it promotes the formation of a close-textured, even surface behind the screed.

Frequency / Pressure of Pressure Bar(s) The pressure bar(s) are moved up and down by a pulsed hydraulic pressure.

These pulses are generated by a rotary valve in the screed at a rate of between 58 and 68 Hz. Hydraulic rams press the pressure bar(s) downwards over the entire pave width. At the end of each pulse, the pressure bar(s) are returned to their original positions by springs acting against the force of the rams. The pressure applied to the pressure bar(s) changes the distance travelled by the pressure bar(s) with each pulse.

3.4 Paver Set-Up

Tamper Stroke / Tamper Speed The length of the tamper stroke and the tamper speed are factors influencing

precompaction of the mix and floating of the screed. On VGELE screeds, the tamper stroke can be set to different lengths.

The longer the tamper stroke, the higher the precompaction and the compaction depth. For this reason, the length of the tamper stroke should be set in accordance with the layer thickness in order to obtain the smallest possible, positive screed planing angle. A negative screed planing angle may result if the tamper stroke is too long for the layer thickness paved. This can lead to an open-textured, cracked surface structure and uncontrolled levelling resulting in irregularities.

Tamper Speed Both the tamper speed and the pave speed have a major influence on

precompaction of the mix. This means that the tamper speed must be adjusted in accordance with the pave speed or vice versa. An optimal relationship has not yet been found. For this reason, the values must be individually adjusted until the smallest possible, positive screed planing angle is obtained and wear on the compacting systems is minimized.

Rigidity of the Screed When making major changes or one-sided changes to the screed planing

angle, torsion of the screed may result.

Screed Freeze Screed Freeze is a briefly activated feature following a paver stop in Screed

Float mode. A pressure of about 30 bar is applied to the piston side of the hydraulic rams for raising / lowering the screed in order to prevent it floating up when resuming paving.

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3.5 Relationship Between Tamper Speed and Pave Speed

While paving, when screed tow point rams are not changed in position, an equilibrium of forces comprising pave speed, screed weight and tamper speed is established. If any one of these parameters changes, this immediately affects the screeds floating behaviour.

Paving with Automated Grade and Slope Control

If automated grade and slope control is used for paving, the desired elevation of the screed can be maintained by increasing the planing angle, but precompaction will not remain constant.

After Compaction by Rolling

When the roller passes over the mix, the amount of extra compaction will differ on account of varying precompaction and result in irregularities in the surface.

Tamper speed and pave speed are very strongly dependent on one another. Any change in pave speed without changing the tamper speed and position of the screed tow point rams will affect precompaction of the mix. If the pave speed is increased without simultaneously increasing the tamper speed, the load bearing capacity of the mix will be reduced and the screed lay a thinner layer at a steeper planing angle.

8m/min. 4m/min.

Low Precompaction

High Precompaction

Pave Speed8m/min. 4m/min.

Pave Speed8m/min. 4m/min.

3.6 Recommended Settings for the Compacting Systems

Tam

per S

troke

(mm

)

Tam

per S

peed

(rpm

)

Vibr

ator

Spe

ed (r

pm)

Pres

sure

Bar

s Pr

essu

re (b

ar)

Laye

r Thi

ckne

ss (c

m)

Pave

Spe

ed (m

/min

.)

Asphalt: Base Course

Asphalt: Binder Course

Asphaltic Concrete: Wearing Course

Asphalt: Combined Base/Wearing Course

Asphalt: Thin Layer

AC 32 T 10 - 60 2 - 4 4 - 7 1,500 - 1,800 2,600 - 3,000 90 - 110

AC 22 T 6 - 10 2 - 5 4 - 7 1,000 - 1,400 2,100 - 2,400 70 - 100

AC 22 B 6 - 10 2 - 5 4 1,000 - 1,400 2,100 - 2,400 70 - 100

AC 16 B 4 - 8 2 - 6 4 600 - 1,000 1,800 - 2,100 50 - 80

AC 11 B 4 - 6 3 - 6 4 600 - 800 1,600 - 1,800 50 - 70

AC 11 D 4 - 6 3 - 6 4 600 - 900 1,600 - 1,800 50 - 80

AC 8 D 2 - 4 3 - 6 2 - 4 600 - 900 1,300 - 1,600 50 - 70

AC 5 D 2 - 4 3 - 6 2 - 4 600 - 900 1,200 - 1,500 Off

SMA 11 4 - 6 3 - 6 4 600 - 1,500 1,600 - 1,800 50 - 80

SMA 8 2 - 4 3 - 6 2 - 4 600 - 1,500 1,300 - 1,600 50 - 70

SMA 5 2 - 4 3 - 6 2 - 4 600 - 1,500 1,200 - 1,500 Off

AC 16 TD 8 - 16 2 - 6 4 1,200 - 1,800 2,200 - 3,000 80 - 110

Mat

eria

l

Type of Pavement

1 - 3 3 - 10 2 500 - 1,400 1,000 - 1,200 Off

94 95


3.7 Functions of the Hydraulic Rams for Raising / Lowering the Screed

3.7.1 Screed Float

Normally, mix is paved with the screed in Screed Float mode. In other words, the piston-side and rod-side valves operating the hydraulic rams for extension/retraction of the screed are open towards the hydraulic oil tank for free extension and retraction of the screed.

3.7.2 Screed Assist

If the bearing capacity of the mix is poor, the screed will not reach the desired elevation even when set to a large planing angle. The Screed Assist function allows pressure to be applied separately to the right and left-hand hydraulic rams from below. This pressure counteracts the screed weight and allows it to float up in accordance with the magnitude of the pressure.

3.7.3 Screed Freeze

The Screed Freeze function is activated automatically following a paver stop in Screed Float mode. The valves activating the hydraulic rams for raising / lowering the screed are closed on both the piston and the rod sides, thus briefly suspending the Screed Float mode

Documents

Paving Booklet English