Sunday, 16 March 2014

What influences efficiency of V-Belt?

V-belt efficiency depends on the load being transmitted, sheave sizes, the number and size of belts, and their temperature. But most of all, efficiency is affected by installation and maintenance factors, such as tension, misalignment, and worn sheaves.
A well-designed, properly aligned and tensioned V-belt drive is most efficient — about 97% — when first installed. With time and use, the belts stretch, lose tension, and begin to slip in their sheaves. The result: efficiency drops to about 94%, provided that the sheaves are in good condition and slippage is normal. To minimize this drop in efficiency over time, keep belts properly tensioned and aligned.

Saturday, 1 March 2014

Most common V belt causes of belt failure.

Listed here are some of the most common V belt causes of belt failure.
        Worn or damaged Sheaves.
        Sheaves Misaligned
        Insufficient Tension
        Wrong Belt Cross-Section or Type
        Improper or Prolonged Storage
        Excessive Heat
        Excessive Oil or Grease
        Use of Belt Dressing
        Abrasive Environment
        Excessive Moisture
        Inappropriate Sheave Material
        Improper Tensioned Idler
        Belts Rubbing Guard
         Belts Pried On or Misplaced Slack
         Defective or Worn Backside Idler
         Excessive Exposure to Oil or Grease
         Use of Belt Dressing
         Worn or Damaged Sheaves
         Insufficient Tension
         Wrong Belt Cross-Section or Type
        Overload Drive-Underbelting
         Insufficient Wrap on Small Sheave
        Foreign Objects In Grooves
        Sheaves Too Small
         Backside Idler
         Sheaves Misaligned
         Improper or Prolonged Storage
         Excessive Tension
         Worn or Damaged Sheaves
         Prying open The Split With a Screwdriver

Saturday, 20 April 2013

Here we are discussing about belt turn over problem. It happen either issue within the machine or improper installation of belt. It can be overcome by replacing correct size V-belt or it should be installed properly. The belt will need to not be pried on, the right belt type and cross section and the belt needs to be tensioned to the manufacturer’s specifications. If you have a machine that has an automatic tensioned and you still have slack then you may have the wrong belt.

If still problem appearing after replacing the belt than move to the machine and check if there is a problem with the sheaves & also check if the sheaves are misaligned you can either place the belt is the groove and see if there is a bend or, place a flat edge along the sidewall of the pulleys and make sure they are straight. In some cases it might pay off for your company to invest in a Gates EZ Align Laser Tool. The Gates EZ Align Laser Tool uses a visible laser to show you whether or not the pulleys are aligned properly. The last step would be to make sure that the bearings on each of the sheaves is still good. If the bearings are bad, the pulley would be able to move out of alignment.

Sunday, 20 January 2013

V-Belt Slippage Causes and Solutions

Belt slippage is one of the common problems on a V-Belt driven system that caused delay & reduces the worth of a Machine.  It’s indirectly or directly affects our Time, Money & Labour.

Reasons like Worn or Damaged Sheaves, Wrong Belt Section, and Insufficient Tension, Excessive Grease or Oil, Excessive Moisture and Insufficient Wrap on Small Sheave are the causes for V-Belt slippage but frequently it happens due to V-Belt Stretchiness.

Improper Installation is also a major reason for Slippage. Generally what happen, when during Installation more Tension is applied on the V-Belt for faster Installation, It causes V-Belt to stretch more than normal.

In case of Slippage Problem we should ensure that the belt on the machine is the correct size and has not stretched. Sheaves also need to be checked. The worn and/or damaged Sheaves will cause the belt to slip. The way to determine whether or not the pulleys are at all defective is to either purchase a tool that sits in the pulleys to make sure that the sides are making contact with the belts, or replace the pulleys.

Always choose the belt as per the requirement of machine to get the maximum output out of it. For example if your machine is being used in areas of extreme moisture then that could be the culprit. Or, if your belt runs on a machine that may have a leak of any sort of liquid that could be the problem as well.

Apart from the above reason one major area of focus is the Cord used in the V-Belt. The Cord used in a V-Belt as a tension member is most often constructed out of a Polyester material and this decay over time. Latest development in Cord is the invention of Kevlar Cord. Kevlar Cord increases life of a V-Belt and give a longer life than the Polyester Cord V-Belt and also offer solution to Slippage Problem.

Another interesting situation is like let’s say that the belt goes from one pulley to a pulley that is only two inches in diameter. A standard belt will have a hard time making sufficient contact with the pulley. To resolve it, use a V-Belt with Cogged instead of a Standard V-Belt.