Sheet extrusion lines

SHEETEXTRUSION LINES

Our historyBandera was established in 1947 by Luigi Bandera and soon proved

to be a strongly expanding company, thus contributing to the actual

development of plastics processing industry in Europe.

In 1950 Bandera became a joint-stock company.

In 1960s - 1970s, company activities underwent remarkable expansion

to reach an industrial scale production, offering a wide and diversified

range of extrusion products (pipes, profiles, sheet).

In 1980s - 1990s the company was acknowledged as one of the leading

companies in extrusion line manufacturing field, in Italy and worldwide.

In 1998 Bandera received ISO 9001 Quality Certificate.

Bandera has recently focussed its product range on three main fields:

blown film, foil & sheet, and pipes (including specific technology for steel

pipe coating).

2

NewsBandera is headquartered in Busto Arsizio (VA), just a 10-minute drive

from Milan Malpensa International Airport. Bandera buildings were

recently renewed to combine industrial series production with quality

check procedures. The company is currently managed by Piero and

Franco Bandera, the founder’s sons, who are keeping investing in

technical improvements of production tools and machinery, and in the

company key source: human resources.

Please find below a brief description to better outline Bandera company:

3 production areas (100,000 sqm)

175 employees

ISO 9001 certified manufacture methods and procedures

A wide and complete range of full extrusion lines (pipes, blown film,

sheet and foil)

Engineering and R&D Depts, keeping Bandera on the cutting edge of

innovation

Bandera has recently allocated its manufacturing process in three sites:

B1: Administration and marketing offices, assembly department, test

room, and shipping department

B2: Screw, barrel, and extrusion head (CNC instrumentation)

manufacturing site

B3: R&D Department, with dedicated test rooms

Bandera is widely acknowledged as world leading manufacturer of sheet

extrusion lines.

Pushing on its broad expertise acquired over many years, its customer-

oriented philosophy and its R&D Dept efforts focussed on new applications

and technologies, Bandera is today able to satisfy the broadest range of

production needs. The configuration of the extrusion lines offered can be

arranged to suit the most demanding requirements in terms of layout,

automation, and ancillary equipment.

Best-selling standard sheet extrusion lines are outlined in this brochure.

Bandera is definitely proud of the top technical standards applied to its

extrusion lines. Any bandera extrusion line is manufactured to suit the

broadest customer needs. Perfectly tailor-made.

Sheet extrusion lines

3

Process materials: ABS, HIPS, PE, PP, ASA

Standard thickness range: 1,5 mm ÷ 12 mm

Sheet width: up to 3000 mm max

Sheet structure: single-layer or coextruded

Hourly output: up to 1200 Kg/h

Sheet extrusion line for shockproof products

Process materials: PS

Standard thickness range: 1,5 mm ÷ 7,0 mm




Worldwide construction standardization of home appliances has led to

an optimization of the extrusion process size.

Finished product width ranges between 600 mm and 900 mm.

The extrusion line is equipped to provide high outputs. Production line

control is eased by sheet standardized width.

Sheet extrusion line for refrigerators

4

Process materials: ABS, PS, PS-K, PMMA





Sheet extrusion line for caravan and sanitaryware applications

Process materials: polyolefin resins

Standard thickness range: depending on finished product embossing




Available selection of finished product grammage, and non-wovens

coupling grammage to suit any customer requirements.

Sheet extrusion line for building and industrial applications

5

Process materials: PMMA, PC, PET-G, PS-K, SAN





The production of high quality acrylic sheet from PMMA and PC intended

for top-level prestigious architectural applications require specifically

arranged extrusion lines. Besides standard - and suitable - chemical

and physical-mechanical features, the finished product - in order to be

classified as fine optically superior product - must have outstanding

aesthetic characteristics, among others:

No blend residues

Requirement compliant hue

Brightness and transparency

Perfect blend of master batches and additives

No optical distortions

The must-have features for a valuable product.

L. Bandera has been investing in technical innovation for over 20 years to

offer superior-product manufacturing machines, focussing on high-tech

research aimed at ongoing process enhancement.

High optical quality sheet extrusion line and for acrylic products

6

3

Estrusore bivite corotante

Process materials: ABS, PMMA, PET





Masking unit for the application of sheet protective film

Due to optimal PET characteristics required for furniture applications,

Bandera extrusion lines feature co-rotating twin-screws - of which

Bandera is world-leading manufacturer.

The innovative corotating twin screw extruder L/D:52 grants multiple

advantages:

Outstanding venting efficiency: larger vacuum areas prevent process

material pre-treatments (drying and dehumidification process)

Quick colour switching over, due to minimized material residence time

Excellent mixing capacity

Power saving (-30% if compared to a single-screw extruder)

Multi material processing capacity obtained with standardized screw

geometry

Sheet extrusion line for furniture industry

Complete 3-layer ABS/PMMA extrusion line

7






Possibility of surface embossing, brushing and corrugating. The extruded

product shall guarantee weldability, resistance to atmospheric agents,

and suitable mechanical strength. The extrusion line can be designed

and manufactured to meet any customer requirements.

Sheet extrusion line for geoliners

Geomembrane extrusion line. Standard configuration layout

8

3

Process materials: polyolefin resins, polyesters, glass fibres and mineral

fillers

Standard thickness range: 0.2 mm ÷ 3.0 mm




The line is equipped with no. 2 flat die heads.

Further to product application studies carried out by Bandera R&D Dept,

the mechanical resistance to elongation, tear, punching and drilling of

the extruded product is maximized.

Resistance to light, ozone, chemical agents, high and low temperatures,

fire (halogen and mineral filler free composition) and - needless to say

- water, is 100% guaranteed. The application range is extremely wide:

foundations, tunnels, subways, swimming pools, etc.

Sheet extrusion line for waterproofing applications

Extrusion line for waterproof applications. Standard configuration layout

9

Sheet extrusion line for automotive Process materials: polyolefin resins, mineral fillers and powder stabilizers,

liquid plasticizers

Standard thickness range: 0.5 mm ÷ 3.5 mm




Exclusive cutting edge technology for internal lining with both

aesthetic and functional purposes, intended for top-class vehicles

Dimensional stability even after thermoforming

High-performance soundproofing and thermal insulation

Over fifteen applicable formulations

10


Standard thickness range: depends on composite finished product to be

obtained

Sheet width: depending on composite finished product to be obtained

Sheet structure: composite, single-layer or coextruded

Hourly output: depends on composite finished product to be obtained

(coupling material grammage, and extrusion line output)

The line core feature consists in the in-line manufacture of a finished

product via “in-calender” coupling of semifinished reels (nonwovens,

paper, aluminium, etc.) with polyolefin sheet exiting the flat head.

Line accuracy and user-friendliness depends on the high level of design

and construction. The finished product, besides complying with coupling

chemical and mechanical requirements, features extremely refined

aesthetics.

Composite products obtained with coating extrusion lines have a wide

application range (from building and construction fields to food and

industry sectors).

Sheet extrusion line for coating lamination

Extrusion line for coating applications. Standard configuration layout

11

Process materials: HDPE, PP (and high molecular weight resins ensuring

elevated chemical and physical-mechanical features)

Standard thickness range: 1.0 mm ÷ 40.0 mm (2 flat heads)

Sheet width: up to 3000 max

Sheet structure: single-layer or coextruded (twin-screw and/or single-screw

extruders)


The line is intended for semi-finished products for chemical-industrial

applications (liquid tanks), cut flatbeds, technical components (e.g.

flanges, gears, outsoles, etc.).

Being stress-cracking, and cut-, abrasion- and impact-resistant (typical

characteristic of some materials), high-thick sheet can be used in the

automotive field for external covers (e.g. pick-ups).

High-thick sheet extrusion lines outstand for their specific design.

Extremely high thicknesses require dedicated post-sizing in-calender

sheet processing and thermal stress relieving (for sheet dimensional

stability) to avoid issues at cutting and thermoforming stages.

Possibility to obtain blends with mineral fillers and straighteners

directly in line (extrusion line with co-rotating twin-screw extruders)

Calender equipped with hydraulic system for up-down displacement

(available sheet path up to down or down to up)

Movable and power-driven double roller bed. Independently

temperature controlled rollers

Multi-emission point X-ray heating system for sheet molecular

thermal stress relieving

High-thick sheet extrusion line

High-thick sheet extrusion line

12

Process materials: PP, PET

Standard thickness range: 200 µm ÷ 1.2 mm




Calenders in vertical, inclined or horizontal configuration, equipped with

chromium-plated (and super-finishing), satinized or embossed rollers.

Air blade systems and simple or double effect vacuum box for thin sheet.

Process materials: EVA (Ethylene Vinyl Acetate)

Standard thickness range: depends on finished product to be obtained

Sheet width: up to 2500 mm


Hourly output depends on finished product to be obtained

The silicon photovoltaic module is normally obtained with sandwiched

together material layers - the so-called “laminated layer” - and with

other ancillary materials making the sandwich suitable for use.

As a standard, the laminated layer is made of the following materials:

Glass (4 mm thick, as a standard)

EVA - Ethylene Vinyl Acetate

Monocrystalline or polycrystalline cells

Backsheet (made of PET or glass)

Sheet extrusion lines for paper and cardboard industry

Sheet extrusion line for solar panels

13

Co-rotating twin-screw extrudersSheet extrusion lines are increasingly provided with co-rotating twin-screw

extruders. A choice due to top flexibility and versatility offered by twin-screw

technology.

Co-rotating twin-screw extruders are thoroughly designed and

manufactured by Bandera. Extrusion screws are made in high

performance wear resistant XDBD steel, and extrusion barrels are made

in nitrided steel and/or bimetal alloy (screws and barrels consisting of

independent modular sections, accurately assembled).

Co-rotating twin-screw technical features - the result of R&D studies and

yearly expertise - offer the extrusion line several advantages, as follows.

Versatility and flexibility

The standardized geometry of the extrusion screws enables various

materials processing (PET, PP, PS, ABS, HDPE,LDPE, …) and ensures

no material stress, besides easing production control and schedule.

Possibility to process up to 100% ground skeleton material (industrial

waste), to manufacture products obtained by Chemical (dedicated

additives) or physical (gas injection) foaming processes, and to use

mineral filler powders, e.g. talc, calcium carbonate, titanium dioxide

(see photo here beside)

Mixing and self-cleaning

The intermeshing and co-rotating extrusion screws guarantee

minimized material residence time, together with quick and easy

colour switching, thus resulting in outstanding time and material waste

reduction - a peculiar characteristic deriving from the compounding

sector

Melt purification

The outstanding efficiency of the venting system (up to 10mBar ÷

15mBar residual vacuum, sufficient for the whole extrusion barrel)

allows for hygroscopic material processing with no need for material

pre-treatment (dehumidification, drying, crystallization, …).

Furthermore, it is undoubtedly worth mentioning that Bandera

technology is FDA approved in the food packaging sector

14

Power saving

The important power saving ensured by co-rotating twin-screw extruders

is due to the reduced motor torque if compared with single-screw

extruders.

Power saving can be up to 35%, depending on process material.

Bandera twin-screw extruder production range is detailed in the table

below.

Co-rotating twin screw L:D ratio

2C 55 mm

34:1, 42:1, 52:1

2C 70 mm

2C 85 mm

2C 105 mm

2C 135 mm

2C 170 mm

15

Single-screw extrudersSingle-screw extruders currently play an important role in sheet extrusion

line manufacturing. Today, Bandera offers its customers a wide range

of extruders to comply with all market needs in terms of productivity,

efficiency, and quality.

Bandera designs, manufactures and tests its machines independently

and manufactures extruders up to 380 mm in screw size.

Extrusion screws are made in nitrided steel. Possibility to apply special

wear resistant alloys onto the thread edge (Stellite or Colmonoy 56/57).

Extrusion barrels are made in nitrided steel and/or bimetal alloy.

Thanks to its long-lasting experience (Bandera single-screw extruder

No. 3 dates back to 1943 and is proudly displayed at Bandera premises)

and to several technological innovative enhancements over the years,

Bandera has always been a leading company in this field.

Sheet extrusion line production range is mainly divided into 2 categories:

Single-screw extruders for polyolefins and polyamide (PE, PP, PA, ...)

non vented (for processing non-hygroscopic materials)

Single-screw extruders for styrene and acrylic polymers (PS, ABS,

PC, PMMA, ...) vented (for processing hygroscopic materials)

16

Single-screw extruders for polyolefins and polyamide (PE, PP, PA, ...)

Single-screw extruders for styrene and acrylic polymers

(PS, ABS, PC, PMMA, ...)

Single screw extruder L:D ratio

TR 35 mm

25:1, 28:1, 30:1

TR 45 mm

TR 50 mm

TR 60 mm

TR 65 mm

TR 75 mm

30:1, 35:1

TR 80 mm

TR 85 mm

TR 90 mm

TR 100 mm

TR 120 mm

TR 140 mm

TR 160 mm

TR 180 mm

TR 200 mm

Single screw extruder L:D ratio

TR 50 mm

35:1, 38:1

TR 60 mm

TR 65 mm

TR 75 mm

TR 80 mm

TR 85 mm

TR 90 mm

TR 100 mm

TR 120 mm

TR 140 mm

TR 160 mm

TR 180 mm

TR 200 mm

17

Proper material loading and dosing into the extruder is undoubtedly one

of the key factors to be taken into account - in fact, it is considered the

first process variable. Single- and twin-screw extruders are equipped

with different dosing systems:

Continuous gravimetric dosing system, of the loss-in-weight type, for

co-rotating twin-screw extruders (the so-called starve-fed extruders)

Volumetric dosing system for single-screw and co-rotating twin-screw

extruders

Gravimetric dosing system of the batch type (by weights) for single-screw

extruders

Bandera designs and properly sizes various dosing systems to meet

any customer needs: the material can be dosed in different form, e.g.

granules, production waste, flakes, additives, masterbatch, filler powders

(mineral or otherwise). In case of low-density ground materials, the

single-screw extruder is completed with a force feeder to ensure utmost

process efficiency. Bandera prefers to include the above equipment into

the scope of the supply, so as to integrate full extrusion line control in the

general control desk.

Dosing and loading systems

18

Melt filtering

Melt gear pump

Melt filtering is a key step of the extrusion process to ensure final product

quality. Besides, it is important to safeguard gear pump, extrusion head

and calender roller integrity, especially in case of recycled materials.

Standard filtering systems are hydraulically operated, and equipped with

filtering screen plates (2, 4, 8, …) for screen changing without production

interruption (continuous filtering) and without altering of foil/sheet

quality.

Process stability is ensured by melt pressure and temperature control,

arranged upstream and downstream of the filter.

The basic function of the melt gear pump is to grant constant melt flow

(i.e. under precise and constant pressure and output conditions) from the

extrusion head: high precision gearing is aimed at ensuring the finest

accuracy tolerances.

Gear pump dimensioning and design depend on process material

features and required outputs.

Due the integrated control system provided by Bandera control panel,

the operator can easily control production variables by regulating melt

gear pump parameters.

Process stability is ensured by melt pressure and temperature control,

arranged upstream and downstream of the pump.

19

A feedblock for the production of sheet featuring A-B-A, B-A-C-D and A-B-A-C-D structure (picture and 3D layout above).

Here below, feedblocks for the production of 3- and 7-layer sheet.

Provided the very wide range of products required by the sheet sector

(raw materials, structures, thickness an width ranges, outputs, …), Ban-

dera flat heads are ad hoc designed and manufactured for each extru-

sion line. Besides, as a standard, they are equipped with a feedblock

whenever sheet structure is multi-layer.

The feedblock comprises a tempered and stabilized stainless steel case:

inner melt flow channels are superrefined and/or chrome plated.

Layer distribution is managed by interchangeable selector plugs and

apposite melt flow and orientation diverter valves.

Flow channels are designed and manufactured depending on process

material rheology and single layer output: these features are of core

importance for the utmost precise distribution of sheet layers.

Sheet extrusion line feedblocks

20

An extrusion head (either single-channel or multi-channel) is made in

tempered and stabilized stainless steel: inner melt flow channels are

superrefined and/or chrome plated.

Flow channels are designed and constructed depending on material

rheology and global machine output.

Thermoregulation of head and lips is extremely accurate and involves

specifically designed high efficiency cartridge-type resistance heaters.

The extrusion head can be complete with several appliances, depending

on production needs, such as:

Internal or external decklers to easily and quickly adjust sheet width

Distribution bar to evenly distribute the melt flow over the entire sheet

width

Fast-gap adjustment system to regulate the gap by moving part of the

head body

Air blade systems and vacuum box for the production of thin sheet

In the pictures here below, manufacturing process and operation of

single-channel die head for the production of mid-thick sheet.

It is worth highlighting that in case of multi-layer sheet from different

rheology materials, the employ of extrusion heads with separate

channels is of the utmost importance for high-quality extrudate.

Multi-channel extrusion heads are more complex, besides requiring

independent thermoregulation and melt flow control.

Flat heads for sheet extrusion lines

21

CalendersIn sheet extrusion and co-extrusion lines, the calender is the actual

process core, where material is sized and cooled at the extrusion head

outlet.

Calenders differentiate for several design and construction

characteristics, e.g.:

Configuration: horizontal, (15°, 30°, 45°, 60°) inclined and vertical

Roller closing system, i.e. hydraulic, pneumatic and mechanical

Roller gap adjustment, i.e. mechanical - manual, mechanical -

power-driven, pneumatic with special design valves

Width, diameter, and quantity of the cooling/calibrating rollers

Roller construction, i.e. spiral or transverse hole cooling

Roller cooling/thermoregulation, i.e. by water or by oil

Roller surface finishing, i.e. mirror polished, satinized, or embossed

Drive and electronic control

22

Pushing on a number of calenders manufactured over the most recent

years and the expertise derived from a proactive cooperation with its

customers, Bandera meets the most various and demanding requests.

To continue along this positive trend and offer its customers an ongoing

professional service, Bandera has dedicated an exclusive product-

oriented staff to this series of extrusion lines. For process optimization

as well as for special production needs, Bandera calendering systems

are completed - among others - as follows:

Hydraulic system for calender vertical displacement (available sheet

path up to down or down to up)

Movable and power-driven upper and/or lower roller beds complete

with independently thermoregulated rollers

Multi-emission point X-ray heating system for sheet molecular

thermal stress relieving

Innovative cooling and polishingtechnology for composite sheet

23

Ancillary downstream equipment for semi-finished product further

processing:

Calender roller cleaning systems, power-driven, to reduce frequency

of line downtime

Idle and/or power-driven roller beds with independent thermoregulation

for calibrating high quality and high-thick sheet

Sheet ennoblement (lacquering, surface treatments…)

Infrared ray heating systems aimed at sheet thermal stress relieving

Various laminating systems for sheet ennoblement and/or composite

sheet production

Masking machine for the application of protective film on the extruded

sheet

Heavy-duty haul-off units

Multiple and combined longitudinal and transverse cutting systems

Side trim cutters and transversal sheet breakers

Blade granulators complete with granule conveying equipment

Manual stacking systems, either semi-automated or fully automated

Thin and/or flexible sheet winding systems

In-line extruded sheet quality control system, via video cameras and/

or polarized lights

Downstream ancillary equipment

Bandera ultimate machinery:

Calender roller cleaning system, by movable power-driven cart equipped with pneumatic pad and detergent solution distributor

Masking unit: installed on a longitudinally sliding roller bed. Calender roll control stations arranged underneath the roller bed

Single or multiple roller beds equipped with power-driven rollers temperature-controlled by dedicated thermoregulation stations

24

Longitudinal “K” cutters with heated blades, sliding on roller bed

Transversal cutter for acrylic materials

Longitudinal cutting system with power-driven circular blades

Automatic stackers for shockproof and embossed materials

Transversal cutter for acrylic materials

Trim edge-cutting system with breaker

and belt conveyor to the blade granulator

Combined transversal cutting unit:

Guillotine-type (shear) and circular saw blade

Movable transverse cutting system with swarf exhauster

Automatic stackersfor high quality sheets

Haul-off unit and transversal cutting unit

for acrylic materials

25

Company/Factory LAN

EWon

Machine LAN

Operator Panel

Serial

PLC

PSTN, ISDN

Line control andcentralized managementThe centralized control of all extrusion line parameters has proved to be

a key factor in production management.

Markets have increasingly become sensitive about labour costs, quality

control, product traceability systems and connection to company network

(or remote connection) for production line software check and inspection.

To meet its customers’ - and prospects’ - needs, Bandera has designed a

specific software control architecture. The control system is based on an

industrial workstation for Windows operating system. The line master

PLC, interfaced with the industrial workstation, is in turn connected

with ancillary equipment PLCs and with single unit remote I/O module

via field bus. Due to the control architecture, all line parameters are

available for remote connections aimed at production control, material

management or remote assistance by Bandera technicians.

The user interface has been designed with special care - from hardware,

with a wide colour monitor to software, with intuitive synoptic graphics,

from which the operator interacts via the touch screen HMI. Bandera is

proud to mention that its customers have played a key role in Bandera

machine development: following their suggestions, today Bandera

machine quality definitely outstands on the global market.

26

Bandera relies upon its specialists to support its customers with

an accurate after-sales service, both at the line start-up and

testing, and at the production stage. Cutting-edge technology is

at Bandera customers’ disposal, at any time.

In order to comply with its customers’ maintenance needs,

Bandera has established a dedicated efficient Aftersales and

Spare Parts Division.

Pushing on its high tech solutions, Bandera offers its customers

turnkey extrusion lines - from engineering and design to

construction, assistance and assembly stages. Besides, Bandera

has drawn up specific training programs dedicated to customers’

personnel - the best way to understand how to operate new

machineries and to retrofit existing ones.

Technical service

27

PLASTICS MACHINERYEXTRUSION TECHNOLOGY SINCE 1947

Visit www.luigibandera.com to view Bandera complete production program

Costruzioni Meccaniche Luigi Bandera S.p.A.C.so Sempione, 120 | 21052 Busto Arsizio (VA) ITALY

Tel. +39 0331 398111 | Fax +39 0331 [email protected] | luigibandera.com

REV

3/SH

EET/

GB

/12/

11

Technical specifications provided for illustrative purpose only and subject to change without prior notice.

EXTRUDERSBLOWN FILM PIPES & COATING PELLETIZING

Documents

Sheet extrusion lines