13/10/05 Newall Linear Encoders Keep Pallet Pooling Trend on Track

CHEP is a global leading company in pallet and container pooling
services, handling literally millions of pallets & containers serving
customers in a wide range of industrial and retail supply chains,
including sectors such as consumer goods, food, home improvement,
beverage, petrochemical and automotive. However, standard wooden
pallets are susceptible to breakage after extensive use, meaning that
pallet maintenance is a vital part of CHEP's business strategy, which
seeks 100% customer satisfaction. Rather than simply throwing damaged
pallets away, profitability is enhanced by stripping and replacing
individually damaged pallet elements (which are then sent for
recycling). This intricate task is aided by the use of Spherosyn™
linear encoder technology from Newall Measurement Systems on pallet
stripping machines at CHEP's Pontefract site.

Newall's innovative SHG range of Linear Encoders is capable of
achieving an accuracy of +/-3mm, is sealed to IP67 and is resistant to
severe shock, vibration and RFI. The SHG can deliver real-time feedback
at traverse speeds of up to 20m/s. As with all Newall inductive linear
encoders, it is impervious to contamination and requires no
maintenance. A comprehensive measuring length range is offered, giving
travels ranging from 50mm to 10,0040mm.

Pooling is a growing logistics and distribution trend whereby multiple
customers share standard pallets and containers. It offers a strategic
business option for companies that wish to concentrate their capital
expenditure and day-to-day supply chain operations on their core
business. Customers rely on CHEP to manage their equipment pool,
including the repair of damaged units, which is why the role of
Newall's SHG linear encoders is so critical.

"The encoders look for a marker on the SHG rod, which gives a height
for the SHG to calculate how far the blade has travelled to reach a
position called 'home'," explains Kevin Dickman, manager of the
maintenance operation at Pontefract. "Once this has been completed, the
machine then does another calculation to determine how far the blade
needs to travel in the vertical plane to reach a given height from home
to the correct cutting height. The blade then cuts the damaged element
from the pallet without causing further elemental damage to other parts
of the pallet."

With a combination of six SHG (digital) and Spherosyn (analogue) linear
encoders on each of the three pallet stripping machines at CHEP,
reliability is a key issue, particularly as the machines are expected
to operate 24 hours a day, seven days a week. Yet Mr Dickman says that
reliability has been one of the outstanding virtues of the Spherosyn
encoders. "I would list accuracy, robustness, reliability and extended
warranty as the four key reasons that Spherosyn and SHG linear encoders
were selected for use on these machines," he states.

Although working tolerances for the application at CHEP are
surprisingly tight at +/-0.3mm, the Newall linear encoders are capable
of achieving much closer limits, +/-0.003mm in some instances. The
secret behind their growing popularity is the innovative design. Housed
within the stainless-steel tube that constitutes the body of the
digital encoder is a column of precision preloaded nickel plated
elements. The reading head uses a 10 kHz drive coil to induce an
electromagnetic field in the elements, and the variation in field is
detected by a series of pickup coils. Voltage from the pickup coils is
analysed by the onboard electronics to indicate the position.

Working in an environment that inherently creates large quantities of
sawdust is a tall order for many conventional glass-based linear
encoders that are more prone to contamination than Newall's inductive
technology, which provides greater robustness as there are no moving
parts. For this reason all Newall linear encoders carry an IP67 (NEMA
6) environmental rating and will continue to provide accurate and
reliable readings even when fully submersed in water, oil or coolant.

CHEP employs over 7700 people worldwide. Globally the company manages
the daily movements of over 265 million pallets and containers from a
network of over 440 service centres in 42 countries. Blue chip
customers include Procter & Gamble, Carrefour, Kellogs, Esso, Shell,
Wooloworths, Kraft, Nestle, Tesco, Unilever, Hewlett Packard, Ford and
GM.

At the Client
Parm Jalaf
Newall Measurement Systems Ltd
Technology Gateway
South Wigston, Leicester
LE18 4XH
Tel: +44 (0) 116 264 2730
Fax: +44 (0) 116 264 2731
parm.jalaf@newall.co.uk
www.newall.co.uk