Proper Belt Storage and Handling
People with sound inventory management know that keeping stock of parts and consumables is critical, especially items that need urgent replacement upon failure.
Like power transmission belts, for example.
- Why stock up on belts?
- Do belts expire?
- Precautions when storing belts
- Methods of belt storage
- Reminders before you install the belt
People keep extra belts on hand and ready to use because they want to be able to (almost) immediately replace a belt that snaps.
It’s bad enough that you’ll have to stop operating the equipment when that happens, but not having an immediate replacement belt makes the situation worse.
When you need belts, and you don’t have them on hand:
- You can’t always buy one right away, as some stores may not keep a lot of belts in their inventory.
- Even if stores have stock (or if they can source it for you), you’d usually still have to wait for a few days to get your belts.
- The equipment is essentially rendered useless, and therefore can’t produce output.
- You’ll accrue productivity losses due to unplanned downtime
Okay, so it makes sense to keep belts in stock, but it begs another question.
While there’s no absolute rule, it’s best to follow manufacturer recommendations so the belts won’t be worn prematurely on storage.
For instance, according to page 19 of this Gates Preventive Maintenance + Safety booklet:
Belts may be stored up to six years if properly stored at temperatures less than 85˚F (29.5˚C) and relative humidity less than 70%.
If the storage temperature is higher than 85˚ F (29.5˚C) , the storage limit for normal service performance is reduced by one half for each 15˚F increase in temperature.
Belts should never be stored at temperatures above 115˚F (46˚C).
At relative humidity levels above 70%, fungus or mildew may form on stored belts. This has minimal effect on belt performance but should be avoided.
When equipment is stored for prolonged periods of time (over six months), the belt tension should be relaxed, and the storage environment should meet the 85˚F (29.5˚C) and 70% or less relative humidity condition.
If this is not possible, belts should be removed and stored separately in a suitable environment.
- Keep them clean and free of dust or any debris
- Store them first in a proper box where you won’t have to crimp them.
- Store them in a cool and dry room at constant temperature
- Store them in a place with humidity between 50% to 80% (to avoid possible formation of fungus or mildew)
- Store them in the original box / packaging with which they came
- Lose the label (lest you have a hard time identifying their specs later on)
- Store them in areas with extreme (or constantly fluctuating) temperatures
- Store them in areas with high ozone levels
- Store them in areas where evaporating solvents or other chemicals are present in the atmosphere
- Store them on the floor unless a suitable container is provided, as they may be exposed to water leaks or moisture or be damaged due to traffic
- Store them outdoors
- Store them near heat sources such as air flow from heating devices, heaters, radiators or even windows (which could expose them to sunlight and moisture)
- Store them near transformers, electric motors, or other electric devices that may generate ozone
- Store them under tension
- Tie them like this (photo c/o Gates)
- Back-bending, crimping, deforming, rolling or twisting them
- Bending them sharply to diameters that are smaller than the minimum recommended diameter for inside bends and 1.3 times the minimum recommended diameter for back side bends, according to this Gates flyer
- Coiling them as much as possible (although v-belts can be coiled sparingly, as you’ll see in the table below)*
- Exposing them to acids, adhesives, alkalis, lubricants, oils and other substances that may compromise its rubber composition
- Exposing them to direct sunlight, rain or snow
- Hanging them on hooks and pins such that there are sharp bends and too much tension that could deform the belt
- Stacking them, such that the belts in the bottom can be damaged
- Storing them near “areas where evaporating solvents or other chemicals are present in the atmosphere,” according to this Goodyear flyer
*According to the Gates Preventive Maintenance + Safety booklet, v-belts can be coiled in loops for storage purposes. Each coil results in a number of loops. One coil results in three loops, two coils results in five loops, etc. The maximum number of coils that can be used depends on the belt length. If coiling a belt for storage, refer to this table below for the limits:
Depending on the belt type, different storage techniques are used. You can maintain serviceability and dimensions for certain belt types as guided by the recommendations below (taken verbatim from Gates Industrial Power Transmission Preventive Maintenance + Safety 2019):
- V-belts: V-belts are often stored on pegs. Very long belts should be stored on sufficiently large pins (of not less than the minimum bend diameter, or crescent-shaped “saddles”, to prevent their weight from causing distortion. Long V-belts may be coiled in loops for easy distortion-free storage.
- Joined v-belts and multi-ribbed belts: Like V-belts, these belts may be stored on pins or saddles with precaution to avoid distortion. However, belts of this type up to approximately 3000 mm are normally shipped in a ‘nested’ configuration, and it is necessary that especially joined V-belts be stored in a naturally relaxed form, and only nested or rolled up for transportation.
- Synchronous belts: For synchronous belts, nests are formed by laying a belt on its side on a flat surface and placing as many belts inside the first belt as possible without undue force, providing the belt bend radius is no smaller than the minimum recommended pulley size for that belt. When tight, the nests can be stacked on a flat shelf, up to 8 nests high, without damage. Belts over approximately 3000 mm may be ‘rolled up’ and tied for shipment, providing the bend radius is no smaller than the minimum recommended pulley for that belt. These rolls may be stacked for easy storage. Avoid small bend radii by inserting card tubes, the size of minimum bend radius for the belt, at the point where the bend is in the belt.
- Variable speed belts: These belts are more sensitive to distortion than most other belts. Hanging them from pins or racks is not recommended. These belts should be stored on shelves. Variable speed belts are often shipped in ‘sleeves’ slipped over the belt. They should be stored on shelves in these sleeves. If they are shipped ‘nested’, untie the nests and store them in a relaxed position.
You’re ready to replace the damaged/worn belt, but first here are some reminders to give your belts a chance of longer service life and make the installation labour worthwhile.
- Replacing the other belts if it’s in a dual-groove / multi-groove pulley as well, even if they don’t show visible signs of wear, because it may only be a matter of time before those “good” ones break,** and you don’t want another downtime just to take care of that. We’ve learnt from experience that only replacing one or two belts from a set is a false economy because it will almost always lead to reduced belt life for all the belts.
- Replacing the set with belts from the exact same brand/manufacturer and variant, to increase your chances that they will wear evenly and equally**
- That the replacement belt has no visible signs of damage
- That the replacement belt indeed matches the specs of the outgoing one, for proper fitting (and here are some guides with illustrations for identifying and measuring v-belts and synchronous/timing belts)
- That the related peripherals, such as the pulleys, bearings and shafts, are in good condition with no visible damages
- That the drive and driven pulleys are properly aligned, lest it could quickly wear the belts
- That the pulley grooves are clear of burrs, dust, grease, oil and rust
- That you apply proper tension upon initial fitting and after “breaking in” (to account for some stretching while running it on the motor with and without load) -- too loose will produce excessive noise and shorten the belt's service life, and too tight will shorten the bearing’s service life
- Lubricate the belts themselves
**Provided other maintenance factors (eg. adequate lubrication of bearings and pulleys, proper pulley alignment and tensioning etc.) are set properly.
- Use common sense and don’t do anything that will obviously deform the belt (especially its tensile cord)
- Don’t cheap out on belts, as you’ll get what you paid for in terms of quality
- Choose a belt from a reliable manufacturer like Gates