Embed Size (px)
Citation preview
VESTAMID® NRGThe highest level of efficiency and performance
The bundle of energyHigh performance solutions for the energy market
Page
Page
Page
Page
Page
4
6
14
18
22
VESTAMID® NRG
Gas pipes
VESTAMID® NRG – beyond what PE can offer
Superior performance characteristics for Intended applications – VESTAMID® NRG
Maximizing infrastructure assetsand contributing to the bottom line
Proven record of performance
Steel pipe protection
High-end application capabilities
Installation methods
Horizontal directional drilling
Soil displacement method with non-steered displacement hammers
The plow method
Dynamic ramming with non-steered ramming machines
Pipe bursting
Frequently Asked Questions
Contents
VESTAMID® NRGThe highest level of efficiency and performance
About EvonikGerman-based Evonik Industries is one of the world leaders in specialty chemicals. The high performance polymers of Evonik are suitable for a virtually unlimited range of uses, including a particularly large number of applications in the energy sector. High performance polymers are used in flexible photovoltaic modules, wind power facilities, and in the oil and gas industry. Depending on the application, these polymers provide protection against corrosion or chemicals, increase the safety of energy transport, or enhance the efficiency of energy generation.
More energy with VESTAMID® NRGThe polyamide 12 VESTAMID® NRG is specifically developed for energy efficient gas and oil pipelines. VESTAMID® NRG contains the previously introduced and established products LX9020, LX9026, LX9030 and LX9032 under the new name NRG. These polyamides have extraordinary resistance to mechanical stress, stress fracturing, and chemicals such as crude oil. Thanks to these properties, they can be used to protect the exterior and interior of onshore and offshore oil and gas pipelines.VESTAMID® NRG bundles energy by making the transport and extraction of fossil energy sources more efficient and by contributing to generating renewable energies.
Further applications of polyamide 12The applications of polyamide 12 range from sophisti-cated line systems such as fuel lines, through core insulation in the cable industry and catheters in medical technology, to precision injection-molded parts like impellers and control-valve housings in machine and equipment manufacture.
4
General properties of polyamide 12• Minimal water absorption: Molded parts show almost no dimensional changes with variation in atmospheric humidity.• Extraordinarily high impact resistance and Charpy notched impact strength, even well below freezing point• Good to excellent resistance to greases, oils, fuels, hydraulic fluids, and many solvents as well as to salt solutions and other chemicals• Excellent resistance to stress cracking, including for metal parts encapsulated by injection molding or embedded into the plastic• Excellent abrasion resistance • Low dry sliding friction coefficient as compared with steel, polybutylene terephthalate, polyacetal, and other materials• Noise and vibration damping properties • Excellent resistance to fatigue caused by frequent load change• Easy processability
5
Gas pipes
VESTAMID® NRG 2101 yellow is a high molecular grade PA12 material developed by Evonik. Its superior performance characteristics make it an ideal choice for expanding the use of thermoplastic piping systems at higher operating pressure and larger diameters to replace metallic piping systems in a safe and cost effective manner.
VESTAMID® NRG 2101 yellow piping systems offer a 25 percent increase in the overall operating pressures as compared to the closest other high pressure plastic material.
Besides extending the operating pressure limits of thermoplastic piping systems, VESTAMID® NRG 2101 yellow offers many of the same benefits, and in most instances more superior performance, as conventional PE piping systems.
• Tough and durable• Corrosion resistant• Resistant to heavy hydrocarbons• High resistance to Slow Crack Growth and Rapid Crack Propagation• Increased installation efficiencies• Worry free performance
These characteristics make VESTAMID® NRG an ideal choice when selecting appropriate thermoplastic piping materials in extending your gas distribution infrastructure.
VESTAMID® NRG 2101 yellow material complies with ASTM F2785, ISO 22621 and ISO 16486 specifications. A complete system exists to allow gas utility com-panies to take advantage of the numerous benefits of VESTAMID® NRG 2101 yellow piping systems at higher operating pressures.
Read further to discover how VESTAMID® NRG can help your company maximize its capital budgets and extend the benefits of plastic piping materials within your natural gas distribution infrastructure in a safe and reliable manner.
VESTAMID® NRG – beyond what PE can offer
VESTAMID® NRG – Polyamide 12 (PA12) Polyamide 12 is a high performance thermoplastic polymer with increased performance characteristics that translates into safe operations over the life of the installed pipeline. It has a considerable record of safe and proven experience in many demanding applications, including fuel lines in passenger cars, air brake tubing in trucks, and off-shore applications.
Realize long distances – coiled VESTAMID® NRG pipes
6
Property Unit Test procedureVESTAMID®NRG 2101 yellow
Material designation PPI TR-4 PA12
Cell classification ASTM D3350 PA423
Pipe properties
Density at 73°F resp 23°C g/cm³ ISO 1183 1.02
Hydrostatic design basis at 73°F (23°C) psi ASTM D2837 3,150
Hydrostatic design basis at 140°F (60°C) psi ASTM D2837 2,000
Minimum required strength MPa/psi ISO 9080 18/261
Rapid Crack Propagation critical pressure (PC), 32°F (0°C) bar/psig ISO 13478 30/435
Pipe test category ---- ASTM D2513
Material properties
Tensile strength at yield MPa/psi ASTM D638/ISO 527 39/5,760
Elongation at break, Type I bar % ASTM D638/ISO 527 >200
Flexural modulus MPa ISO 527 1,300
PENT (2.4 MPa) h ASTM F1473 >2,000 hours
PENT (4.8 MPa)1 h ---- >2,000 hours
Moisture absorption 74°F resp. 23°C/50% r.h. % ISO 62 0.8
Water absorption (saturation) % ISO 62 1.5
Thermal properties
Melting range DSC 2nd heating °C/°F ISO 11357 177/350
Vicat softening temperatureMethod A 10N °C/°F ISO 306 176/349Method B 50N °C/°F ISO 306 150/302
1 Test specimen and overall test methodology is same as ASTM F1473 but at increased stress levels
A – Pipe and fittings data sheet
Material Properties Standard Specimen Requirement Unit
VESTAMID® NRG 2101 yellow
Melting point ISO 3146, ISO 11357 granules 170 -195 °C/°F 177/350
Heat of fusion ISO 3146, ISO 11357 granules --- J/g 65
Glass transition temperature ISO 3146, ISO 11357 granules --- °C/°F 36/97
Heat capacity DSC ISO 3146, ISO 11357 granules --- J/(g•K) 2.02
Thermal expansion coefficient ISO 11359 2“ SDR11 --- µm/(m•K) 144
Thermal conductivity coefficient ASTM C177 --- W/(m•K) 0.25
Softening point VicatA (10N) ISO 306 derived from ISO 527/1A --- °C/°F 170/338
Softening point VicatB (50N) ISO 306 derived from ISO 527/1A --- °C/°F 150/302
Heat distortion temperature (HDT A - 1,80 MPa) ASTM D648 derived from ISO 527/1A --- °C/°F 45/113
Heat distortion temperature (HDT B - 0,45 MPa) ASTM D648 derived from ISO 527/1A --- °C/°F 145/293
Longitudinal reversion ISO 2505 2“ SDR11 max. 3 % 0.33
B – Physical data
7
Superior performance characteristics for the intended application – VESTAMID® NRG
The key to building world class gas piping systems is using materials with superior performance char-acteristics and a proven track record of safety for the intended application.
VESTAMID® NRG exhibits the following key performance characteristics and benefits which makes it an ideal material for high pressure gas distribution applications.
C – Longterm mechanical properties
Gas pipes
Advantage VESTAMID® NRG: coiling is not an issue
Lightweight and flexibleVESTAMID® NRG 2101 yellow piping systems are lightweight with a greater degree of flexibility as compared to steel or other metallic piping materials while retaining their toughness and durability.
The lightweight nature of VESTAMID® NRG 2101 yellow piping systems reduces the overall transpor-tation costs and make it easier for crews to work with it on the job site. The increased flexibility allows for piping systems to be transported in coils thereby reducing the number of joints or fittings and allow the use of innovation trenchless installation techniques such as planting and plowing.
The net effects are improved installation efficiency, reduction in overall installation costs, and an overall positive impact to the environment.
Increased toughness and durabilityExtensive research data and actual field performance validate the overall toughness and durability of VESTAMID® NRG 2101 yellow. Experience has proven that VESTAMID® NRG 2101 yellow retains its tough-ness and durability over a wide range of installation conditions including higher temperatures, excessive bending strains, highly compressive and/or contami-nated soils. Most importantly, the increased tough-ness and durability of VESTAMID® NRG 2101 yellow allows it, to withstand the potential impact of third party damage better than most thermo-plastic materials being used today.
Material properties Standard Specimen UnitVESTAMID® NRG 2101 yellow
LPL ISO 9080 2“ SDR11 MPa 19.04
MRS ISO 12162 2“ SDR11 MPa 18
HDB 73°F ASTM D2813 2“ SDR11 psi 3,150
HDB 140°F ASTM D2813 2“ SDR11 psi 2,000
MOP (bar) = (MRS * 20) / (2 * (SDR-1)) MOP = Maximum Operating Pressure MRS = Minimum Required StrengthMOP (psi) = ((HDB * 2) / (SDR – 1)) * 0,4 SDR = Standard Dimension Ratio HDB = Hydrostatic Design Basis
LPL = Lower Prediction Limit
8
Material properties Standard Specimen Requirement UnitVESTAMID® NRG
SCG, GTI ISO 22621 / 13478 2“ SDR11 min. 500 h >2,000
SCG, Gastec ISO 22621 / 13479 110 mm SDR11 min. 500 h > 810
PENT test, GTI ASTM D2513 / F1743 Plaque min. 500 h >1,000
Squeeze-off, GTI ASTM D2513 / ISO 22621 2“ SDR11 min. 500 h >1,000
Rock impingment GTI Method / ISO 22621 2“ SDR11 min. 500 h >1,000
Earth loading GTI Method / ISO 22621 2“ SDR11 min. 500 h >1,000
Bending strain GTI Method / ISO 22621 2“ SDR11 min. 500 h >1,000
D – Longterm mechanical properties
Increased design lifeOver 40 years of field experience with PE piping systems have demonstrated that one of the leading causes of field failures with plastic piping systems is due to Slow Crack Growth (SCG) as a result of various factors including: improper manufacturing or installation practices such as squeeze-off, exces-sive bending strain, poor fusion alignment, etc; and environmental factors such as rocky soils or point loads. (Tab. D)
To ensure the safe use of plastic piping materials against the failures due to SCG, both ASTM and ISO standards have incorporated performance based requirements and tests including the Pennsylvania Notch Test (PENT Test) and Notch pipe Test.
Evonik has performed extensive testing of its VESTAMID® NRG 2101 yellow that validates the superior SCG resistance characteristics and ensures greater long term performance. Compared to other thermoplastic materials, VESTAMID® NRG 2101 yellow performs extremely well under the PENT test. To illustrate, VESTAMID® NRG 2101 yellow did not fail even after 2,000 hours under the PENT test at a stress of 4.8 MPa which is two times greater than the current test requirements per ASTM F1473.
Increased long term strengthBoth ASTM and ISO have established protocols to characterize the long term strength of thermoplastic pipes used in gas distribution applications. As compared to other thermoplastic materials, VESTAMID® NRG 2101 yellow has a higher hydrostatic design basis (HDB) and a higher minimum required strength (MRS) that provides operators with greater flexibility in their overall design approach to satisfy capacity considerations. (Tab. C)
With VESTAMID® NRG 2101 yellow piping systems, operators can make informed decisions for the most effective outside diameter and wall thickness com-binations to use. For a given design pressure, gas utility companies can utilize thinner wall pipe sizes thereby increasing flow capacity and increasing savings in material costs. For a given SDR (ratio of the outside diameter to wall thickness), gas companies can significantly increase the operating pressure as compared to other thermoplastic materials.
Squeeze-off at joined VESTAMID® NRG pipes
9
Besides the PENT test, the VESTAMID® NRG 2101 yellow also exhibits excellent resistance to surface scratches and notches. In comprehensive tests per ISO requirements, the VESTAMID® NRG 2101 yellow pipe materials did not fail after 1,000 hours with a 30 percent notch using a test pressure of 20 bar at 80°C (290 psig at 176°F).
Most importantly, the results of extensive testing has shown that the VESTAMID® NRG 2101 yellow has excellent resistance to persistent point loads resulting from a rock or other hard objects in the backfill material. In tests performed at the Hessel Institute, the VESTAMID® NRG 2101 yellow material showed NO failures at 31 bar and 60°C (450 psig at 140°F) under the combined effects of internal pressure and point load. The results confirm the ability to safely use VESTAMID® NRG 2101 yellow without the need for additional backfill or sand bedding. (Tab. E)
Cumulatively, the results show that the VESTAMID® NRG 2101 yellow material has ample strength and toughness to resist failure due to slow crack growth under various types of in-service stresses leading to longer design lifetimes. (Tab. E)
Excellent resistance to Rapid Crack PropagationThe results of comprehensive testing have demon-strated that the VESTAMID® NRG 2101 yellow material has excellent resistance to failures from Rapid Crack Propagation (RCP).
While actual RCP failures are rare, all materials are susceptible under the right set of conditions. To ensure only those materials with ample resistance to RCP failures are used for gas distribution applica-tions, both ASTM and ISO standards require a series of tests including Small-Scale Steady State (S4 Test) and Full-Scale Test (FST). The FST test is considered to be the referee test.
The results of Full-Scale RCP tests confirm the excellent RCP resistance of VESTAMID® NRG 2101 yellow over the range of increased operating pressures.
RCP results, Full scale Test in accordance to ISO 13477
Excellent chemical resistanceA unique benefit of the inherent molecular make-up of the VESTAMID® PA12 material is that it has excel-lent chemical resistance to heavy hydrocarbons making it an ideal candidate material for extremely harsh environmental conditions. As a result, the VESTAMID® PA12 material is an ideal choice where the soils have been contaminated due to gasoline spills, etc. (Tab. F)
Pipe size P Critical at 0°C/32°F
SDR 11 pipe 110 mm Pc,fs ≥ 30 bar/435 psig
SDR 11 pipe 6-inch IPS Pc,fs ≥ 25 bar/362 psig
NO FAILURES
NO PENT FAILURES at 4.8 MPa for over 2,000 hours
NO FAILURES at 20 bar and 80°C (290 psig and 176°F) with a 20 percent NOTCH for over 1,000 hours
NO FAILURES at 20 bar and 80°C (290 psig and 176°F) with a 30 percent NOTCH for over 1,000 hours
NO FAILURES for 3/6 test specimens at 20 bar and 80°C (290 psig and 176°F) with a 50 percent NOTCH for over 1,000 hours
Gas pipes
10
Secondary stress Test criterion Results
Point load
Test pressure = 31 bar/450 psigHoop stress: 14.75 N/mm2
Test temperature = 60°C/140°FTest time >22,500 hourswith no failures
Point load
Test pressure = 31 bar/450 psigHoop stress: 10 N/mm2
Test temperature = 80°C/140°F3 mm inside notch Crack growth after 10,939 hours
Rock imingement
1,3 cm/0,5“ IndentationTest pressure = 20 bar/290 psigTest temperature = 80°C/176°F
Test time >1,000 hourswith no failures
Earth loading
5% deflection of outside diameterTest pressure = 20 bar/290 psigTest pemperature = 80°C/176°F
Test time >1,000 hourswith no failures
Bending strain
20 times ODTest pressure = 20 bar/290 psigTest temperature = 80°C/176°F
Test time >1,000 hourswith no failures
E – Longterm mechanical properties
Change in weight (%)Change in tensile strength at yield (%)
Material properties Standard Specimen Requirements Results Requirements Results
Control ASTM D2513-06 split ring --- --- --- ---
Mineral oil ASTM D2513-06 split ring <0.5 0 max. -12 1
Toluene in Methanol ASTM D2513-06 split ring <7.0 2.8 max. -40 -12
Methanol ASTM D2513-06 split ring <5.0 2.5 max. -35 -20
Ethylene Glycol ASTM D2513-06 split ring <0.5 0 max. -12 -5
Tertiary Butyl Mercaptan ASTM D2513-06 split ring <0.5 0 max. -12 -10
F – Chemical resistance
11
Maximizing infrastructure assets and contributing to the bottom lineGiven its superior performance characteristics, the VESTAMID® PA12 piping systems offer significant economic benefit as compared to other types of piping systems available in the marketplace.
Flexible design alternativesA key advantage of the enhanced performance characteristics of the VESTAMID® NRG 2101 yellow material is it enables gas utility companies to imple-ment flexible design scenarios to satisfy their capacity considerations and extending service to areas that were previously cost prohibitive. With the highest MRS and HDB rating of any other approved thermoplastic material, VESTAMID® NRG 2101 yellow can safely operate at pressure equal to or greater than 18 bar (250 psig). Alternatively, for a given line pressure, gas utility companies can choose to reduce the wall thickness and gain the additional necessary capacity to satisfy the critical demand loads during the cold winter months.
Material properties Standard Specimen
Ambient temperature at fusion Requirement Unit
VESTAMID® NRG 2101 yellow
Hydrostatic strength ISO 22621 / 1167 110 mm SDR11 0°C/ 32°F min. 165 h >165
Hydrostatic strength ISO 22621 / 1167 110 mm SDR11 23°C/ 73°F min. 165 h >165
Hydrostatic strength ISO 22621 / 1167 110 mm SDR11 40°C/104°F min. 165 h >165
G – Butt fusion joints
Gas pipes
Proven methods of JoiningThe overall integrity and longevity of any piping system is predicated on its weakest link. In the case of metallic piping systems, this has been joints where mechanical fittings or gaskets are used that tend to corrode of leak over the lifetime of the pipeline.
VESTAMID® NRG 2101 yellow piping systems can be constructed using proven butt heat fusion or electro-fusion joining methods. It has been proven that joints made using either of these two methods are stronger than the actual pipe enhancing the overall integrity of the pipeline. The use of these methods do not require additional capital investment since conventional tools used with PE piping systems can be readily used. That is, there is no need for special butt fusion equipment or electro-fusion boxes when joining VESTAMID® NRG 2101 yellow pipe segments. This allows for the seam-less and transparent integration within gas utility companies’ operations.
Availability of an overall complete systemEvonik has partnered with leading gas component manufacturers to offer a complete line of pipe and fittings conforming to the strictest ASTM and ISO product specifications. This enables gas utility com-panies to effectively design, construct, and maintain VESTAMID® NRG 2101 yellow piping systems capable of lasting a long time with worry free service. Transition fittings and risers conforming to ASTM F1973 are available to “tie-in” into existing steel assets. Electrofusion couplings and saddles per ASTM F2767 are also available to connect the PA12 piping segments and extend lateral connections.
Joining of gas pipes with heat fusion
Joining of gas pipes with electrofusion
12
Reduced life cycle costsLike PE, the VESTAMID® NRG 2101 yellow piping systems offer superior range of economic benefits for gas utility companies as compared to metallic piping.
• The VESTAMID® NRG pipe is lightweight and easier to handle and transport• The VESTAMID® NRG piping systems eliminate the need for long term corrosion control measures• Given its inherent flexibility, the VESTAMID® NRG pipes can be provided in coils thereby reducing the number of joints that must be performed in the field resulting in increased productivity and reduced installation costs• Together with the pipe coils, the use of planting/ plowing installation techniques can be used to install more pipe over a shorter period of time as compared to other methods of installation• Depending on the application and capacity con- siderations, the VESTAMID® NRG piping systems can be utilized with thinner wall applications and thereby further reducing material costs and maxi- mizing capacity• The VESTAMID® NRG pipes can be utilized with an array of low-cost trenchless rehabilitation techniques including horizontal directional drilling, sliplining, pipe bursting, etc.• VESTAMID® NRG 2101 yellow retains its chemical, physical, and mechanical stability over its design life and does not experience premature oxidative degradation, circumferential expansion, or loss of long term strength over its design life.
Connection to steel pipeline with transition fittings
Proven record of performance
The VESTAMID® NRG 2101 yellow piping systems have been extensively tested under actual field settings over the range of pipe sizes, intended operating pressures, and installation environments. The results provide unequivocal proof that the VESTAMID® NRG 2101 yellow piping systems provide a valuable alternative to metallic piping and peace of mind.
In general, VESTAMID® NRG 2101 yellow piping systems offer gas utility companies with flexible design scenarios to replace metallic piping systems or to extend the use of thermoplastic piping systems at higher operating pressures in a safe, reliable, and cost effective manner.
Coiled pipes and heat fusion
13
High-end application capabilities
VESTAMID® NRG offers a flexible, mechanically tough casement system that combines the advan-tages of polyethylene coating and cement mortar casing.
Advantages of VESTAMID® NRG as encasement material• Unusually high impact resistance and toughness, even at low temperatures• Excellent stress cracking resistance• Excellent wear resistance• Low sliding friction coefficient
Product characteristics compared with otherencasement materialsVESTAMID® NRG has higher Shore hardness than polyethylene or polypropylene. In contrast to poly-ethylene or propylene encasement, therefore, the polyamide encasement offers both the corrosion protection provided by the barrier effect and me-chanical protection for the encased steel pipe.
Application areas for the new encasement material are found in non-conventional installation technologies such as:
• Horizontal directional drilling• The soil displacement method with non-steered displacement hammers• Dynamic ramming• Plow technology
Steel pipe protection
14
H – VESTAMID® NRG 4101 yellow and NRG 4901 black for high performance steel pipe protection
Material properties Unit Test method Typical value
Density at 73°F resp. 23 °C g/cm3 ISO 1183 1.02
Tensile strength at yieldMPa psi ASTM D638 / ISO 527
39 5,760
Elongation at break % ASTM D638 / ISO 527 >200
Flexural modulus MPa ISO 527 1,300
Moisture absorption at 73°F resp. 23°C/50% r.h. % ISO 62 0.8
Water absorption (saturation) % ISO 62 1.5
Thermal properties
Melting rangeDSC 2nd heating
°F °C ISO 11357
350 177
Vicat softening temperature
Method A 10N°F °C ISO 306
349 176
Method B 50N°F °C ISO 306
302 150
VESTAMID® NRG protection: Realize long distances with plowing
VESTAMID® NRG protection: Realize non-disruptive crossings under streets, rivers, channels with HDD
15
VESTAMID® NRG is applied on the steel-pipe surface by established extrusion methods used for PE or PP applications. Preliminary tests and pilot projects have yielded impressive evidence of the performance of VESTAMID® NRG. It was already clear in the preliminary tests that, due to its greater hardness, VESTAMID® NRG encasement showed as expected hardly any scoring, while of polypropylene encasement pipe insertion leaves clear tracks.
In trenchless installation it must be ensured that the coating of the steel pipe is not damaged. Usingthe cathodic corrosion protection method, it wassuccessfully demonstrated in the pilot projects thatthe PA12 coverings were not in any way damagedduring the installation process.
An initial pilot project for HDD installation wascarried out in Algermissen, (Germany). For E.ONAvacon, a 300 m run of pipe was laid under a canal.No relevant damage to the VESTAMID® NRG layer was detected, either visually at the pipe section in the directional drilling borehole or by cathodiccorrosion protection measurements.
In a further pilot project, the plow method was used over a 1.5 km run near Wallersdorf (Germany), on a commission from Wasserversorgung BayrischerWald (WBW).
Another example of applications of this type inoffshore technology is reeling. The pipes are weldedonshore into a kilometer-long run, spooled ontolarge pipe reels, and later laid as a run on the highseas. In this installation technology, the steel tubeseven show plastic deformation, a stress that thecorrosion protection layer must also be capable ofwithstanding.
Steel pipe protection
16
60
50
40
30
20
10
0-50 -40 -30 -20 -10 0 10 20 [°C] -58 -40 -22 -4 14 32 50 68 [°F] Temperature
Notched impact strength in accordance with DIN ISO 179-1/1eA
VESTAMID® NRG PP
-50 -40 -30 -20 -10 0 10 20 [°C] -58 -40 -22 -4 14 32 50 68 [°F] Temperature
80
70
60
50
40
30
20
10
0
Tensile testing in accordance with DIN ISO 527
VESTAMID® NRG PP HDPE
Tens
ile st
reng
th a
t yie
ld [M
Pa]
80
70
60
50
40
30
20
10
0 LDPE HDPE PP VESTAMID® NRG
Shor
e ha
rdne
ss D
(roo
m te
mpe
ratu
re)
Shore D hardness in accordance with DIN EN ISO 868
A comparison of notched impact strengths demonstrates the excellent properties of VESTAMID® NRG against those of polypropylene, especially at low temperatures.
VESTAMID® NRG offers a greater degree of Shore hardness than polyethylene and polypropylene.
The fact that this material is harder also shows in the strength values it achieves, such as stress at yield. Polypropylene, which is stronger than polyethylene, can only be used at temperatures to 0°C/32°F.
17
Installation methods
Horizontal directional drilling
Horizontal directional drillingDirectional drilling has seen an enormous boom in recent years. Directional drilling operations that would have appeared inconceivable just a few years ago are now routinely performed at installation sites. Drilling is often carried out underneath and across rivers and other water bodies, and directional technology even allows drilling below industrial complexes. The application spectrum extends over all pipework for the supply of gas, district heating, and drinking water, and the installation of pressure lines for sewers. The installation technique is extremely eco-friendly,causing minimal ecological damage that is restrictedto points in the immediate vicinity of the system.Many factors favor the use of directional technologyeven in urban areas: The technique scores overopen-trench methods in terms of construction timesand costs, licensing procedures, soil displacement,surface restoration, and traffic disruption.
The combination of fluid-assisted drilling withimpact support allows propulsion and steerability indifficult soils (with large-particle components, fairlylarge rock inclusions, or building-rubble deposits) ofsoil class 5, and in some cases up to soil class 6.
The stringent requirements and expectations for thetasks to be accomplished demand precise location andsteering of the drilling. For insertion of plastic pipes(particularly those carrying gas and drinking water)the pulling forces must not exceed the values specifiedin GW 321, 322, and 323. Horizontal directionaldrilling is described in GW 304 (Pipe Driving) andATV-A 125 and the relevant regulations.
Advantages of the method• No opening up of useful surfaces, no surface damage (to road surfacing, front gardens, etc.), and no restoration required; therefore strong economic advantages• Low social costs by avoidance of diversions, closures of traffic lanes, setting up of signaling systems, etc.• Short setup times, short installation and construction times• Particularly cost-effective for river crossings• Measurement of pulling force and determination of position are possible• Broad application spectrum
HDD with VESTAMID® NRG gas pipes
18
Horizontal directional drilling
Horizontal directional drilling
Soil displacement method withnon-steered displacement hammersThe soil displacement method has been establishedfor three decades as a technique for underground pipe installation. A pneumatically operated displace-ment hammer creates an underground cavity into which are inserted short or long plastic or metal pipes up to DN 200, preferably without socket ends. The pipes are introduced in lengths of up to 40 m, depending on the soil, either simultaneously or in a second work step.This technique allows trenchless crossing of traffic routes, house service connections, preparation of anchoring, bypassing of obstacles, and other measures. The 2-stroke methodDepending on the soil, the soil displacement ham-mers attain a ramming speed of up to 15 m/h. The soil displacement method is described in ATV-A 125 and GW 304 (Pipe Driving), and other relevant regulations.
Soil displacement method with non-steered displacement hammers
The plow methodPlowing technology has been very successfully usedsince the 1970s for laying of power and phone lines.It is particularly suitable for large, open, cross-country stretches where long line lengths are necessary; however, plowing can also be used over shorter distances and for lines in less readily accessible areas. Installation of these lines in sloping ground and the crossing of water bodies (with water levels of up to 1.20 m) present no technical problems, thanks to the plow design with its four booms adjustable in any direction.
This method is particularly suitable for soil types that are easily displaced, but even large-particle soils with a high proportion of stone present no problems.
Advantages of the method• Financial savings of up to 50 percent• High daily capacity of up to 5,000 m possible• Short setup and construction times• Low HR costs• Fuel consumption reduced 90 percent• Plowing and line installation in a single operation• No groundwater lowering required• Minimal traffic disruption• Small working area• No topsoil removal• Low soil compaction• High installation quality
Plowing withVESTAMID® NRG protected steel pipes
Source: www.tracto-technik.com
19
Horizontal directional drilling Soil displacement method with non-steered displacement hammers
Installation methods
Dynamic ramming with non-steered ramming machinesDynamic pipe driving by the ramming method usespneumatically operated pipe-driving machines. These allow installation of open steel pipes as casing or product pipes up to 4,000 mm in diameter over lengths of up to 80 m in soil classes 1-5 (and in some cases also in soil class 6, easily detachable rock) particularly cost effectively and without jacking abutments, under rail-road lines, expressways, and rivers.
Individual pipe lengths are pushed forward in successionafter welding. Due to the robust one-piece construction, a large ram at full capacity can generate an impactenergy of 40,000 Nm, optimally transferred over the entire pipe string to the front cutting edge. The average ramming speed is 10 m/h.
The ramming technique is described in ATV-A 125and GW 304 (Pipe Driving) and the relevantregulations.
Advantages of the method• Little opening up of useful surfaces, low surface damage (to road surfacing, front gardens, etc.), and little restoration, therefore strong cost advantages• Low social costs by avoidance of diversions, closures of traffic lanes, setting up of signaling systems, etc.• Short setup times, short installation times• The soil core remains in the pipe during ramming, so there is no water penetration when rivers are crossed.• Minimal cover, i.e., no large-scale trenches• Broad application spectrum
Dynamic ramming with non-steered ramming machines
1. Ramming 2. Soil removal
20
Dynamic ramming with non-steered ramming machines
Pipe bursting
Pipe burstingThe pipe bursting method is an approved technique which is applicable according to the latest generally accepted technical standards.
A pipe bursting machine is pulled through the old defective pipe. Its dynamic impact energy bursts the old pipe and displaces the fragments into the surrounding soil. A new pipe, of equal or larger diameter, is pulled in simultaneously. The old bore course must be usable for the new pipeline. Lateral inlets or bends have to be opened for a safe, tight and professional connection. The soil surrounding the old pipe must be displaceable, the distance to existing pipelines should be >0,5 m.
The old pipe can be made of clay, cast iron, asbestos cement, plastic or unreinforced concrete. Pipelines requiring replacement usually have longitudinal cracks, are leaky, are offset, have missing pipe pieces, no pipe bedding or have partially or completely collapsed. With burstlining it is not always necessary to carry out internal high pressure cleaning or remove any of the old pipeline. Damaged inliners can be replaced by new pipes with the burstlining method by using a special bladed cutting head.
The machine bursts the damaged pipeline and pushes the fragments into the surrounding soil. Simultaneously the bore profile for the new pipe is expanded. The machine is pulled by a winch, which ensures line and level is maintained through the existing bore path.
The ground around the old pipe is usually easily penetrated. There are virtually no upsizing limitations. The ground plasticity allows, if necessary, the new pipe carrying capacity to be increased by up to two nominal sizes. Groundwater lowering is only necessary in the starting and exit pits.
The annulus around the new pipe can be filled by using a bentonite/cement-mortar mix during the boring procedure. A mortar collar is formed around the new pipe giving full surfaced adhesion and pipe support to the surrounding soil.
PA12 pipes are especially recommended for this pro-cedure. These pipes are highly resistant, sufficiently flexible and easily adapt to align with the old pipeline. Expanding up to two nominal sizes and strengthening of the pipe wall is possible.
Advantages of the method• Environmentally friendly, trenchless pipe installations • Applicable for all types of damaged pipes • Increased capacity by one or two nominal pipe sizes is possible • Long pipe lengths without joint sockets, pressure pipes can be replaced, too • Improvement of the bedding conditions by filling the pipe annulus • Innovative, quick - avoids unwanted social costs • Safe in accordance to technical regulations • Easy price saving calculations in advance • Long life GUARANTEE for new pipes • SIMPLE - SAFE - EFFECTIVE
Dynamic ramming with non-steered ramming machines
© T
ract
o-Te
chni
k . w
ww
.trac
to-te
chni
k.de
Burst lining with VESTAMID® NRG gas pipes
Source: www.tracto-technik.com
21
Pipe burstingDynamic ramming with non-steered ramming machines
Does the VESTAMID® NRG pipe expand in the circumferential direction and lead to issues in the field like other Polyamide materials?
No! The VESTAMID® NRG material has been extensively tested in the laboratory and stringent field conditions. The results demonstrate that the VESTAMID® NRG material retains its chemical, physical, and mechanical stability.
The VESTAMID® NRG material was subjected to the comprehensive tests per ASTM D2837 to ensure that creep deformation was not a limit factor and that VESTAMID® NRG pipe specimens retain their physical properties per the respective product specifications.
Comprehensive field tests at significantly higher pressures, approximately 330-345 psig (23-24 bar) for more than 3 years, validate that the VESTAMID® NRG retains its original geometric properties as specified under the respective product specifications.
What are the moisture absorption characteristics of the PA12 materials?
Like all Polyamide materials, VESTAMID® NRG materials tend to absorb moisture at relative low rates as compared to the other polyamide materials. The equilibrium moisture content is 1.5 percent for VESTAMID® NRG as compared to 8.5 percent for PA6 and 1.8 percent for PA11.
Given the relative low level moisture absorption, the cumulative results of tests demonstrate that this does not adversely affect the overall strength and/or integrity of joints (heat fusion or electro-fusion).
Does the yellow pigment adversely impact the overall performance of the VESTAMID® NRG pipes or cause premature degradation as observed with other Polyamide materials?
No. Evonik has comprehensive protocols in place to ensure that the final VESTAMID® NRG material compound (resin, stabilizers, pigment) is chemical compatible and stable over the life of the pipeline. The results of ageing studies on actual pipe specimens removed from service show that the VESTAMID® NRG piping systems retains its mechanical, physical, and chemical properties over a wide range of installation environments.
Frequently Asked Questions
22
Are there special repair fittings available for PA12 piping systems?
A significant benefit of the VESTAMID® NRG piping system is that existing construction and maintenance practices specific to PE are readily transferable to PA12 piping systems. As a result, gas utility companies can employ the same safe and effective practices which they routinely utilize to address emergency response and repair considerations for their VESTAMID® NRG piping systems as they currently do with the PE piping systems.
Is a complete PA12 piping system available?
Yes. A complete line of pipe, fittings, and appurtenances necessary to construct and maintain high pressure and large diameter VESTAMID® NRG pipelines exists and is made in accordance to strictest ISO and ASTM standards and specifications.
Are there special considerations when joining the VESTAMID® NRG pipes?
No. A key benefit of VESTAMID® NRG piping systems is that they allow for the seamless and transparent integration within your company. Qualified heat fusion procedures have been developed through rigorous testing which are analogous to established joining procedures for PE materials.
Electrofusion fittings made from VESTAMID® NRG materials and conforming to strict ASTM and ISO specifications are also available. These fittings can be installed using conventional electrofusion universal boxes commonly used by gas utility companies.
The ability to utilize conventional joining practices and existing equipment makes the VESTAMID® NRG material an ideal choice for your company’s opera-tions. The joining procedure is described in the technical rules of the DVS* 2207-16 (related tool welding of pipes and piping parts).
* Deutscher Verband für Schweißen und verwandte Verfahren e.V. German society for joining and related procedures
23
Evonik Industries AG High Performance Polymers45764 MarlGermanyphone +49 2365 49-9227fax +49 2365 49-809227www.vestamid.com
03/M
a/10
00/e
This information and any recommendations, techni-cal or otherwise, are presented in good faith and believed to be correct as of the date prepared. Reci-pients of this information and recommendations must make their own determination as to its suitabi-lity for their purposes. In no event shall Evonik assu-me liability for damages or losses of any kind or na-ture that result from the use of or reliance upon this information and recommendations. EVONIK EX-PRESSLY DISCLAIMS ANY REPRESENTATIONS AND WARRANTIES OF ANY KIND, WHETHER EXPRESS OR IMPLIED, AS TO THE ACCURACY, COMPLETENESS, NON-INFRINGEMENT, MER-CHANTABILITY AND/OR FITNESS FOR A PARTI-CULAR PURPOSE (EVEN IF EVONIK IS AWARE OF SUCH PURPOSE) WITH RESPECT TO ANY INFORMATION AND RECOMMENDATIONS PROVIDED. Reference to any trade names used by other companies is neither a recommendation nor an endorsement of the corresponding product, and does not imply that similar products could not be used. Evonik reserves the right to make any changes to the information and/or recommendations at any time, without prior or subsequent notice. ®=registered trademark
