15,000 PRODUCTS IN STOCK - Ptreview

Stema wins major contract
for tyre plant upgrade
Collaboration between Italian engineering company Stema
Service Srl and Control Techniques Italy has resulted in
a substantial contract with one of Italy’s leading tyre
manufacturing groups.
The project, with Unidrive SP
AC drives used throughout, has
produced energy savings, increased
production and resulted in a
reduction in maintenance costs.
Stema Service Srl is an engineering
company providing automation
and process control solutions
for companies in the plastics,
rubber, iron and steel, marine and
galvanic water treatment sectors.
Stema Service routinely works with
automation systems to improve
production throughput, efficiency
and reliability. Recently, with
increased success in international
markets, the company has
standardised on suppliers in key
areas, including PLC platforms and
drives, with Control Techniques
selected as its technological
partner because of the technical
excellence of its product and
application experience and the
worldwide support from the network
of Drive and Applications Centres.
At the tyre manufacturing company,
a variety of applications, including
rubber mixers and calendar lines,
still used DC technologies and
solutions. Following extensive
study, it was determined that a
switch to AC throughout could offer
real benefits in terms of energy
savings, reduced maintenance and
downtime and better throughput
and quality. With the maintenance
needs of the DC motors eliminated,
the company turned its attention
to a review of the control system
leading to a new approach utilising
new PLCs and the introduction of a
digital communication bus system
based on ethernet.
The company has a mixture of
induction and synchronous motors
and has been able to standardise
on Unidrive SP AC drives from
Control Techniques for all of these.
Mixers rated at up to 400kW utilise
Unidrive SPM modular drives,
which, by virtue of their modular
configuration – AC/DC modules,
plus power modules – deliver
greater flexibility for the architecture
of the system, as well as minimising
back-up spares. On the calendar
line, where motor powers vary
from just a few kilowatts up to
90kW, Unidrive SP drives are used
throughout in open loop, closed loop
and brushless servo configurations,
depending on the motors employed.
All drives were fitted with Ethernet
plug-in modules to give a single
Ethernet fieldbus.
Some drives feature SM-Applications
modules, bringing a high level of
motion control functionality down
to the drive level, with the major
benefits of less wiring, less chance
of interference and enhanced
process reliability and performance.
Control Techniques’ Unidrive
SP ‘solutions platform’ AC
variable speed drive range spans
0.75kW right up to 1.9MW and
is configurable into five operating
modes – open and closed loop,
vector, servo and regenerating
mode. A wide range of plug-in option
modules provide extra processing
power and functionality including
extra I/O and field bus connectivity
to most industry standard networks
and compatibility with most position
feedback protocols.
The customer is delighted with the
results of this extensive project, with
the result that other commissions
have followed and Stema Service
has become the point of reference
for other turnkey projects.
For reader enquiries, please
mention PTR:
Joseph Walker,
Control Techniques Ltd,
Ty Rheoli,
Unit 79 Mochdre Industrial Estate,
Newtown, Powys SY16 4LE
Tel: 01686 612900.
Fax: 01686 612999.
Email: joseph.walker@emerson.com
www.Emerson.com
Nov/Dec 2011 P&TR 15
Precise engineering
Feedback
perfectly
packaged
An incremental encoder
sandwiched between the
motor and gearbox to deliver
feedback across the range
Call or visit our web-site
to nd out about this
revolutionery concept
produced with engineers
in mind.