TPT November 2008

69 / 132

Tube Extrusion & Drawing Technology
67 November 2008 ›
Costruzioni Meccaniche Luigi Bandera,
Italy, has recently supplied the latest
extrusion line for multilayer PVC pipes to a
leading European manufacturer of plastic
pipes.
The state-of-the-art line is characterized
by the new counter-rotating twin-screw
extruders and a specifically designed
extrusion head.
This unit is just one part of a larger
supply which includes other lines for the
production of PVC and HDPE pipes with
different range diameters and production
capacity to satisfy the building industry.
The line is designed for rigid PVC (layers
A and C) and foam PVC (layer B), with an
output of 1,000kg/h and diameter range of
250-500mm.
The line is fitted with a dosing system for
the extrusion of the middle layer (foam
PVC) with dedicated design to satisfy the
need of this application.
The line includes extrusion units including a
counter-rotating twin-screw extruder 2B 125
28 L/D (middle layer B with foam PVC), and
Nr 2 counter-rotating twin screw extruder
2B 65 28 L/D (layers A e C Rigid PVC).
For efficient operation, the line features a
calibration tank with automatic control of
vacuum level, and spray cooling tank. In
addition, the line incorporates a haul-off unit
(with 6 caterpillar) for synchronization of the
speed from the main operator control unit.
The line is rounded off with a planetary
cutting unit with cutting disc, automatic
belling machine, and a line supervisor with
industrial PC and colour graphic display.
Established in 1947, the company has
built a large knowledge base in different
plastic material, with particular attention
to plastic pipe application. The company
supplies over 200 extruders each year,
supported by a technical team of highly
experienced engineers.
Costruzioni Meccaniche Luigi
Bandera SpA – Italy
Fax: +39 0331 680 206
Email:
Website:
Gillard, UK, has extended its range of precision caterpillar haul-
off and take-off machines. The new machines are extra-long belt
versions of the Gillard ‘work-horse’ range. The extended belts
are now available in lengths of either 1,500mm or 1,800mm. Belt
widths are either 225mm or 300mm.
The company claims that the longer belts enable higher tractive
efforts to be achieved with considerably less clamping pressure
on the extruded products. This avoids distortion and damage,
particularly to thin-wall products.
The new caterpillars also feature an updated drive package with
direct drive AC servo motors powering the belts. Two digital servo
drives are used in master/slave configuration for optimum speed
control.
The top belt is designed to ‘float’ over any lumps or bumps created
during the start-up of the extrusion line. The entire top boom is
suspended on two air cylinders at either end. This allows the
belt to automatically raise and lower itself over the lumps while
maintaining an adequate grip on the extrusion.
The machines are fully guarded to the latest CE standards. Gillard
offers a wide range of options to enable users to customise the
machine to their needs.
Peter Gillard & Co Limited – UK
Fax: +44 1684 290330
Email:
Website:
Advanced extrusion line for multilayer PVC pipes
 An extrusion head for pipe with a maximum diameter of 500mm
Extra heavy-duty caterpillar haul-offs for effective extrusion
 Gillard’s new machine has longer belts for less pressure on extrusions