Product category:
Measurement systems
News Release from: Newall Measurement Systems | Subject: Chep
Edited by the Manufacturingtalk Editorial
Team on 12 December 2005
Linear encoders keep pallet pooling
trend on track
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.
Chep is a global leading company in pallet and container pooling services, handling literally millions of pallets and 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
This article was originally published on Manufacturingtalk on 4 Mar 2008 at 8.00am (UK)
Related stories
DRO has probe capabilities for lathes/millers
A digital readout system for manually operated lathe and milling machines has white-on-blue LCD display, geometric functions with probe capabilities and graphical dynamic tool position display.
Encoder system checks rotary, linear moves
A flexible, magnetically encoded tape scale for rotary and linear automation applications can be mounted quickly and easily on any fixed surfaces using the adhesive side of the tape.
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.
Further reading
Powerful DRO has dynamic tool position display
A very powerful digital readout unit for manual lathe and milling machine applications offers dynamic tool position display and 4-axis (linear and rotary) simultaneous readout.
Linear encoder ensures accurate cutting-off
An incremental linear encoder fitted to a billet cutting-off saw enables tighter tolerance cutting, so avoiding wastage in cutting expensive nickel alloys stock.
Linear encoders enliven vertical boring mills
Retrofitting linear encoders to the older vertical boring mills/vertical turning lathes reduces scrap and rework rates by improving machgining accuracy and repeatability.
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 and Gamble, Carrefour, Kellogs, Esso, Shell, Woolworths, Kraft, Nestle, Tesco, Unilever, Hewlett Packard, Ford and GM.
• Newall Measurement Systems: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
