Prepping machinery ahead of harvest can be a guessing game. It’s difficult to assess how much life is left in a roller chain, V-belt or auger. Here are some tips:
Roller Chains
- “Replace chains when ‘stretch’ exceeds 2% of their original length,” says Greg Madlinger, Daido Chain. If a chain’s original length is unknown, consider this: The distance between the pins on a roller chain, called “pitch,” is measured in 1/8’s of an inch. The distance between the pins of a #40 chain is 4/8", or the equivalent of 1/2". Pins on a #50 chain are 5/8" apart. Counting the links in a worn chain, then multiplying by the distance between pins, provides original length.
- A simpler method for checking chains is to remove tension and compress, then stretch, two or three links. If there’s more than 1/8" movement between only two or three links, the chain is ready for replacement.
- Rollers in conveyor chains that taper from one side to the other, or are hour glass-shaped, indicate that the chain is in need of replacement.
- Be cautious of half-links in a used chain. A full-length master link has nearly 100% of the strength of a standard riveted link, but a half-link is 35% weaker than riveted links.
V-Belts
- Cracks that extend into the cords of a belt are going to be time bombs. Cracks that extend more than halfway into a belt are on a countdown. Fine cracks on the surface of the back edge of belts are generally considered to be cosmetic.
- Multi-groove V-belts that insist on jumping grooves and cause the belt to run to one side of its sheaves imply one or both sheaves are out of alignment.
- A single-V-belt that’s twisted between its pulleys is slightly “stretched” on one side. It will continue to flip itself no matter how many times it is reinstalled correctly on its pulleys.
- Always loosen tensioning springs before installing belts. Leaving a tensioner tight and then using a big bar to pry a multi-grooved or cogged belt onto a sheave might save time, but it often stretches and damages one edge of the belt.
Augers
- Sharp flighting edges mean the flighting is thinned and could soon fold over. It also indicates the auger’s diameter is diminished, reducing its grain-moving capacity.
- The greatest wear on an auger’s flighting occurs on the discharge end. The intake end might look brand new, while the discharge-end flighting is worn to a razor’s edge.
