The endless V belt that you use today was first developed in 1917 by John Gates in USA. This type of belts were developed to overcome some of the problems associated with leather flat belts. The V belt drive was at that time very compact when compared to flat belt.
This was the time that people were concerned about reducing the trouble. Energy savings and energy efficiency were not that critical. So belt failure and belt slippage were the two great issues that were overcome by V belts.
Leather and laminated cotton fabrics were the early materials with which flat belts were made.
The development in polymer technology could bring out very strong polymers like nylon and this was having very high strength than any natural fibre.
In today's scenario energy conservation, energy savings are most important. Ways and means of saving electrical energy is thought about.
If we look at V belt drive closely, the following aspects that contribute to energy loses can be noticed
1. Belts running loose in the grooves
2. Fluttering belts that indicate misalignment of pulleys
3. Of the multiple belts mounted, some are loose on the pulleys.
4. Worn out belts
5. Worn out pulleys
6. Unequal seating of belts in the grooves
7. Noisy drive.
8.Wobbling pulleys
But how often do we concentrate on all these things?
When we are trying to save electrical energy consumed in motors by proper sizing of motors and by improving the power factor, we fail to concentrate on the efficiency of the drive elements.
We take it for granted that what happens is the way of belt drive.
The availability of V belt and the fact that it will not slip and fall off the drive pulleys has made it the ultimate choice.
There are better ways of improving the belt and pulley drives.
Applying simple logic, many of the above listed 8 aspects could easily be managed if the drive is a single belt drive.
Nylon sandwiched belts, Kevlar card reinforced belts, carbon fibre reinforced belts have come into market to replace the v belts. The nylon sandwich belts are still most economical. The adhesive joint is barely visible and joints made with good skiving machines and adhesives are as strong as the main belt and can very easily take up the belt tension. If we select the right width and if the pulleys are precisely crowned, belt tracking is excellent.
We have offered nylon sandwich belt drives up to 300 HP . Very popular nylon sandwich drives we offer is the Textile Ring Spinning frame main belt drive with a combination of nylon sandwich rubber belt and flat pulleys. Just 90 mm width belt transmits 55 KW and runs for 24 hours 365 days in a year. The designed belt life is 25000 hours. Depending on the maintenance some customers use the belt for more time also.
In many drives a single timing belt does a very good job. Timing belt drives has the advantage of zero slippage. The life of timing belt is also well above 25000 hours if designed properly.
So when a V belt can have as low as 90% efficiency, Nylon Sandwich flat belts can save you up to 7.5 % power. The efficiency could be 99% . Timing belt drive efficiency is close to 99.5 %, the only loss being the energy lost for belt flexing.
The good news is that it is easy to convert the V belt drive to flat belt or timing belt drive. The simple payback on investment is about 7 months.
There may not be much saving in the belt drives less than 5HP or any drive running with only one V belt. If your drive has 3 or more than 3 V-Belts, you can reap the benefit by converting to Nylon sandwich belt drive or timing belt drive.
If you have double sided V-Belt drive, it is high time to scrap it to be relieved of the frequent troubles in maintaining such drives.
15 HP to 75 HP is the ideal range that you can target for the belt conversion.
Belt slippage, higher shaft load are all myths that even well qualified engineers hold and keep supporting the V belt drive.These myths are in direct conflict with fundamental physics of " Friction"
If you can overcome these myths, you can save energy and save efforts of frequent belt changes.
Author: S.Venkatachalapathy, B.Tech. CEO, Exel Textronics
This was the time that people were concerned about reducing the trouble. Energy savings and energy efficiency were not that critical. So belt failure and belt slippage were the two great issues that were overcome by V belts.
Leather and laminated cotton fabrics were the early materials with which flat belts were made.
The development in polymer technology could bring out very strong polymers like nylon and this was having very high strength than any natural fibre.
In today's scenario energy conservation, energy savings are most important. Ways and means of saving electrical energy is thought about.
If we look at V belt drive closely, the following aspects that contribute to energy loses can be noticed
1. Belts running loose in the grooves
2. Fluttering belts that indicate misalignment of pulleys
3. Of the multiple belts mounted, some are loose on the pulleys.
4. Worn out belts
5. Worn out pulleys
6. Unequal seating of belts in the grooves
7. Noisy drive.
8.Wobbling pulleys
But how often do we concentrate on all these things?
When we are trying to save electrical energy consumed in motors by proper sizing of motors and by improving the power factor, we fail to concentrate on the efficiency of the drive elements.
We take it for granted that what happens is the way of belt drive.
The availability of V belt and the fact that it will not slip and fall off the drive pulleys has made it the ultimate choice.
There are better ways of improving the belt and pulley drives.
Applying simple logic, many of the above listed 8 aspects could easily be managed if the drive is a single belt drive.
Nylon sandwiched belts, Kevlar card reinforced belts, carbon fibre reinforced belts have come into market to replace the v belts. The nylon sandwich belts are still most economical. The adhesive joint is barely visible and joints made with good skiving machines and adhesives are as strong as the main belt and can very easily take up the belt tension. If we select the right width and if the pulleys are precisely crowned, belt tracking is excellent.
We have offered nylon sandwich belt drives up to 300 HP . Very popular nylon sandwich drives we offer is the Textile Ring Spinning frame main belt drive with a combination of nylon sandwich rubber belt and flat pulleys. Just 90 mm width belt transmits 55 KW and runs for 24 hours 365 days in a year. The designed belt life is 25000 hours. Depending on the maintenance some customers use the belt for more time also.
In many drives a single timing belt does a very good job. Timing belt drives has the advantage of zero slippage. The life of timing belt is also well above 25000 hours if designed properly.
So when a V belt can have as low as 90% efficiency, Nylon Sandwich flat belts can save you up to 7.5 % power. The efficiency could be 99% . Timing belt drive efficiency is close to 99.5 %, the only loss being the energy lost for belt flexing.
The good news is that it is easy to convert the V belt drive to flat belt or timing belt drive. The simple payback on investment is about 7 months.
There may not be much saving in the belt drives less than 5HP or any drive running with only one V belt. If your drive has 3 or more than 3 V-Belts, you can reap the benefit by converting to Nylon sandwich belt drive or timing belt drive.
If you have double sided V-Belt drive, it is high time to scrap it to be relieved of the frequent troubles in maintaining such drives.
15 HP to 75 HP is the ideal range that you can target for the belt conversion.
Belt slippage, higher shaft load are all myths that even well qualified engineers hold and keep supporting the V belt drive.These myths are in direct conflict with fundamental physics of " Friction"
If you can overcome these myths, you can save energy and save efforts of frequent belt changes.
Author: S.Venkatachalapathy, B.Tech. CEO, Exel Textronics
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