Chain conveyor troubleshoot guide

 

Sl No.	Problems	Potential Cause	Solution
1	Chain rises off from sprocket	1. Excess chain slack.	1. Adjust the amount of slack equally at both sides.
		2. Excess wear at the bases of sprocket teeth.	2.Carryout hard facing of the sprockets
		3. Excess chain extension.	3. Replace the elongated chain parts.
		4. Foreign material stuck to the bases of sprocket teeth.	4. Remove the foreign material from the bases of the teeth.
		5.Reverse rotation of conveyor	5.Avoid reverse rotation of the conveyor when chain tightened is uneven
		6.Uneven chain tightening of chain
2	Chain separates poorly from the sprocket.	1. Sprocket misalignment.	1-Adjust alignment.
		2. Excess chain slack.	2-Adjust the amount of slack.
		3. Excess wear at the bases of sprocket teeth.	3-Avoid uneven tightening of the chain
		4.Uneven chain tightening of chain
3	Wear to sides of link plats and sprockets	1-Sprocket misalignment.	1-Adjust alignment.
		2-Trough width is lesser than required	2-Increase trough & runner flat width as per site conditions & links assembled width
		3-Chain runner flats size is less
4	Poor chain flexure	1-Inadequate oiling/lubrication	1-Lubricate properly, use standard lubricant during chain assy.
		2-Foreign materials between pins and bushes.	2-Wash the chain to remove foreign materials, and then oil it.
		3-Corrosion between bushes.	3-Replace with an environment resistant chain series.
5	Abnormal noise	1-Chain is too tight or too loose.	1-Adjust the chain slack.
		2-Inadequate oiling.	2-Lubricate properly.
		3-Excess wear of sprockets and chain.	3-Replace chain and sprockets or get worn-out area filled & hard face it
		4-Sprocket misalignment.	4-Eliminate contact with the case.
		5-Slats touching the trough
6	Chain vibration	1-Excess chain slack.	1-Adjust slack.
		2-Excess load vibration.	2-Reduce load variation
		3-Excess chain speed leading to pulsation.	3-Use guide stoppers to stop chain swaying.
		4-Chain flexes poorly at some points.	4-Replace the more worn-out chain parts during overall maintenance
		Sprocket wear.
		5-Worn out or more clearances in rollers & bushes
7	Damage to pins, bushes, rollers.	1-Inadequate oiling.	1-Lubricate properly.
		2-Jamed foreign bodies.	2-Remove foreign bodies.
	Deformation of link plate holes.	3-Corroded components.	3-Review chain and sprocket selections.
		4-Use with greater than allowable load.	4-Eliminate the abnormal load, and review chain and sprocket selections
		5-Abnormal load action.
8	Chain link cut or pins cut	1-Overload operation	1-Ensure all over load, ZSS protections are working
		2-Low breaking load of chain	2-Select chain with higher breaking load if this problem persists

Points to be kept in mind

1-Never weld the heat treated chains, as heat effect can reduce the strength & cause chain to break

2-Never go for electroplating of heat treated chain links, as it causes the hydrogen embrittlement failure

3-Do not use new chain on worn out sprockets

4-Gradual elongation of chain above 3%  in total chain length, indicates that the chain will soon jump the sprockets

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