Visit the ExxonMobil Lubricants and Specialties Europe web site

Steps for effective steel belt tracking

A Belt Technologies product story
Edited by the Engineeringtalk editorial team Nov 4, 2003

Steel belts are virtually unstretchable and this characteristic, combined with their high strength to weight ratio, makes them a very powerful tool for design engineers, says Brian Harbison.

Steel belts are virtually unstretchable and this characteristic, combined with their high strength to weight ratio, makes them a very powerful tool for design engineers.

This is particularly so in the areas of precision indexing, repeatable motion and conveying applications.

Metal belts use materials often considered inflexible, such as high-grade stainless steel or carbon steel.

As such, the belts offer unique properties unavailable with more conventional materials.

This includes a high strength-to-weight ratio.

Belts of high tensile strength alloys have low mass, and low inertia.

This allows more of the horsepower to be used to move product, not production line, increasing plant efficiency and lowering operating costs.

Metal belts are accurate because they are virtually unstretchable.

This is particularly important in precision conveying applications like sorting houses.

If you need to know where product is on a conveyor, a metal belt can easily help you achieve that objective.

Solid metal belts are inert, nonabsorbent and suitable for corrosive process environments.

Stainless-steel belts are not affected by organic acids or detergents, nor are they damaged by sharp edges of scraping blades or knives.

They feature a long service life, with a sanitary coefficient similar to glass or enamel.

This permits their use in compliance with the most stringent sanitary requirements.

Solid metal belts perform very well in ovens up to 593C, as well as freezers to well below -45C.

Metal alloys can be selected to provide special heat transfer, electrical conductance, or magnetic properties.

Material can be maintained on the conveyor at a known temperature, improving the quality and consistency of a finished product.

Also, there is no static build-up.

However, because steel belts do not stretch, they will not necessarily self-track.

Accordingly, good tracking features need to be incorporated into systems using steel belts.

These features are simple to apply, reflect good design practice and will help optimise the cycle life of the belts.

For good steel belt tracking, there are a number of system design recommendations.

First, excellent system rigidity with a good, strong frame is important.

Secondly, the belt should run on a support plate made from low friction (UHMW) material such as polyethylene.

Thirdly, there should be axis/shaft adjustment on the idler pulley shaft.

This is typically achieved by the use of mounted bearing blocks.

Once a stable tracking position is achieved no further adjustment will be required unless operating conditions alter.

Belt Technologies has patented an independently steerable pulley as an alternative to mounted bearing blocks, and this is of particular benefit in multibelt systems.

As an addition to axis adjustment/steering, the use of pulley flanges made from glass filled Teflon may be recommended are as an aid to tracking for belts thicker than 0.127mm.

With high-temperature applications it is recommend that the idler pulley (or a separate tensioning pulley) should be under spring tension.

Crowned rollers/pulleys, which are often used with non-steel belts are generally not recommended.

If they are used, it should be in addition to, not in place of, axis adjustment.

For wider belts, typically 1m and above, the use of rubber V-belts bonded to the inner circumference of the steel belt may be recommended.

It should be carefully noted that indexing holes in steel belts are for timing only and should not be used for "forced tracking".

To do so will potentially result in high levels of stress concentration and premature belt failure.

Brian Harbison is European Sales Manager with Belt Technologies Europe.

Send to a friend Send to a friend
Print this page Print this page
Bookmark this page Bookmark this page

Not what you're looking for? Search the site.

Back to top Back to top

Google Ads

 

Contact Belt Technologies

Contact Belt Technologies

Company profile and news

Related Stories

Contact Belt Technologies

 

Newsletter sign up

Request your free weekly copy of the Engineeringtalk email newsletter ...

Sign up now Sign up now

Visit the ExxonMobil Lubricants and Specialties Europe web site

Browse by category

All suppliers A - Z

A Pro-talk Publication

A Pro-talk publication