ATTACHMENT CHAIN SELECTION GUIDE Tsubaki ANSI single and double pitch roller chain is widely used for conveyor service. The following procedure is useful for economical and quick chain selection.
Troubleshooting Guide
Problem
Possible Cause
What to Do
Misalignment of sprockets
Realign sprockets and shafts
Step 1 – Confirm operating conditions Step 2 – Tentatively select chain size Step 3 – Calculate the design tension (Actual chain tension) Step 4 – Verify the chain selection Step 5 – Verify the allowable roller load STEP 1 - Confirm the operating conditions of the conveyor The following information is needed to design the chain conveyor 1. Type of conveyor 2. Method of chain travel 3. Type, weight, and size of materials to be conveyed 4. Weight of materials being transported.
Loose casings or bearings
Tighten set-bolts
Too little or too much slack
Adjust centers or idler take-up
Excessive Noise
Chain and/or sprocket wear
Replace chain and/or sprocket
Inadequate lubrication or no lubrication
Proper lubrication
Chain pitch is too large
Resonance to the vibration cycle of machine to be installed
Chain vibration cycle of chain or machine
Chain Vibration
High load fluctuation
Use torque converter or fluid coupling
Wear on inside of link plate and one side of sprocket teeth
Misalignment
Realign sprockets and shafts
5. Conveyor speed 6. Conveyor length
Excessive chain wear
Replace chain and/or sprocket
7. Lubrication 8. Environment
Chain climbs sprockets
Excessive chain slack
Adjust centers or idler take-up
Heavy overload
Reduce load or install stronger chain
STEP 2 – Tentatively select chain size To tentatively select the chain size, estimate the tension (T) by the following formula. A chain with an allowable load equal to or over the above calculated chain tension may be tentatively selected.
Chain speed too high for pitch and sprocket size
Shorter pitch chain or larger dia. Sprockets
Heavy shock or suddenly applied loads
Reduce shock load or install larger chain.
Broken pins, bushings or rollers
Material build-up in sprocket tooth pockets
Remove material build up or install mud-relief sprockets
T (lbs.) = M T ●• f • k 1 -----------(1) M T : Total weight of material conveyed (lbs) f:
Inadequate lubrication or no lubrication
Proper lubrication
2. Chain sliding
Coefficient of friction, sliding and/or rolling (f 1 and or f 2 of Table 1 and Table 2) Chain speed coefficient (Table 3)
Chain or sprocket corrosion
Install corrosion resistant chain and sprockets
Center distance too big or high load fluctuation
Adjust the center distance or idler take-up
k 1 :
Chain clings to sprocket
Excessive chain slack
Same as above
STEP 3 – Calculate chain tension Next, the chain tension should be calculated using the actual weight of the conveyor chain and material conveyed, as shown below.
Excessive chain wear
Replace chain
Misalignment
Realign sprockets and shafts
Inadequate lubrication or no lubrication
Proper lubrication
1. Chain rolling
Corrosion
Replace with corrosion resistant chains
Chain gets stiff
Excessive load
Reduce load or replace with larger chain
Material build-up in chain joints
Shield drive from foreign matter
Peening or deformed sideplates
Check for chain interference/impact
Subjected to shock load
Reduce shock (install shock damper)
Vibration
Install a device to absorb vibration (tensioner)
Breaking of link plate
Moment of load inertia is too big
Increase chain pitch or no. of strands
Load/speed too high
Check for proper chain selection
Corrosion
Corrosion resistant chains
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