Download The vocation for simplifying high technology has yielded good fruits.

The vocation for simplifying high
technology has yielded good fruits.
For more than thirty years now ST Soffiaggio Tecnica has produced blow moulding machines with accumulator heads for plastic processing. The commitment and enthusiasm
are still the same as in the early Eighties, when ST was established by the technical staff
coming from the company Moi, the first Italian producer of blow moulding machines.
A
lways attentive to the market
evolution and requirements, ST
recently launched the new ISIT range,
a new series beside the ASPI series
(leader in the field of three-dimensional tubes and pipes) and the TA series
(blow moulding machines with accumulator head and without tie bars).
The ISIT series consists of machines
with accumulator head, which are
simple and Italian, as specified by the
name itself (composed of ISI, transcription in Latin languages of the pronunciation of EASY, and IT, abbreviation
of Italian). The company ST wants to
highlight that simplicity does not mean
giving up a high technological level.
Conceived to be robust and easily accessible to all of its fundamental components, the ISIT series assures high
productivity with quite a considerable
energy saving and at an interesting
price.
Specifically designed for the automotive industry, for producing technical
parts and for packaging applications,
the ISIT blow moulding machines are
equipped with accumulator heads of
■ The
FIFO (first in, first out) accumulator head is equipped with a
double-cardioid diverter in order
to assure an evenly formed parison with well-balanced layers. The
quantity of accumulated material
is controlled by a linear transducer
and the extrusion speed is adjustable through 500 points with a proportional controlled on the monitor.
3 to 60 litres capacity, and they utilize
clamping forces from 300 to 1600 kN.
With the ISIT, the company ST wants
to extend sharply its position in the
Packaging Sector and specialize in it.
The machines are ideal for industrial
packaging and are more economical
compared to technologically more sophisticated solutions of big dimensions.
The absence of cooling fans, the reduced torque on the screw, a lower
melt temperature, as well as the automatic adaptation of the screw rpm in
relation to the cycle times, integrate
the process and allow a remarkable
reduction of the energy consumption.
Even the details count:
■ The
structure, designed to be free
of vibrations, is subdivided into two
basic blocks, an upper one for the
extruder and the accumulator head
plus a lower one for the hydraulic,
clamping and blowing units.
The most evident novelties, compared
to the past, are in the clamping unit
and in the extrusion section:
■
The clamping unit allows mounting
the mould from above, and it follows
the concept of “3 platens” clamping
system. The clamping force, generated by a single cylinder, is applied
to the rear of every platen through
a flexing crossbeam, which assures
a balanced distribution of the forces
applied to the mould platens.
■A
rack-type synchronism system
permits simultaneous and synchronized movement of the platens,
which slide on prism guides with
roller bearings.
■A
proportional flow valve allows
adjusting the clamping force, which
can be set directly on the monitor.
The single-screw extruder is based on
the HEX (High Efficiency Extrusion)
technology. It provides a high throughput (see the data table below) with a
significant energy saving, thanks to the
special screw profile and to the thick
and effective heat isolation of its barrel.
■
The upper structure is mobile and
electrically adjustable in the three
directions (vertical, horizontal and
transversal), with the position controlled by magneto-restrictive transducers.
■
An electrically operated extraction
gripper, with seizing assembly, supported by prismatic guides with recirculation ball bearings, will grip
and extract the blown piece.
■The
blowing frame rests on the
lower structure through linear ball
guides. This solution permits freeing the blowing unit and to adjust
the position of the blow pin quickly
and accurately by displacing the
Extruder data table
whole frame. The height of the entire blowing unit is electrically adjustable.
■
The blowing air is monitored by a
proportional valve.
■
The hydraulic movements are generated by a hydraulic power unit
composed of:
- asynchronous motor driving a
pump with pistons that clear the
flow;
-group of bag-type accumulators that permit reducing the installed power while keeping the
same movement speed
- oil filtration and recirculation
circuit, separate from the main
pump;
-oil heating element (resistor)
and oil temperature monitoring
by thermocouple and heating
candle, water-oil heat exchanger,
so that the oil temperature keeps
constant.
■The
electric control cabinet contains a B&R control system with
Ethernet or Power-link communication protocol, remote switches for
various functions, safety devices for
emergencies and the gates
■
All functions of the system are controlled by ST’s proprietary software,
which is easy to manage by the operator.
■All
parameters are set and displayed on the VDU; function graphics permit monitoring the profile of
the parison, as well as the various
movements over 500 points.
L/D
kg/h
50/30
120-150
60/30
200-230
75/30
300-320
100/30
400-420
110/30
520-550
120/30
700-730
■A
particular no-load cycle allows
the operator to check if the entered
data is correct.
■
The complete series includes the
models ISIT 400-500-800-1300-1600.
The range of ST blow moulding machines, always in evolution, respects
the criteria of quality, repeatability, accuracy, reliability and competitiveness.
Those values are the solid foundations
on which ST itself is based in order to
consolidate the ST brand all over the
world. Being on the vanguard, today
like yesterday, is one of the company’s
points of strength and a continuous
stimulus for facing new challenges.