2. Chain Dynamics
2. Eliminate or decrease the decline in the coefficient of friction by using a bearing roller (please consult with manufacturer if the speed is less than 2 m/min.), or use a special kind of lubrication oil (Tsubaki special oil, or others). 3. Increase chain rigidity (AE). A is the chain’s section area, and E is Young’s modulus. To increase AE, use a larger chain. If there are several chains with the same allowable tension, choose the one with the thicker plate. 4. Separate the conveyor into sections and reduce the length of each machine. If stick slip continues to be a problem, consult the equipment manufacturer. 2.3.6 Relative Differences in Chain’s Total Length If you want to achieve a precise positioning of more than two chain lines to be used in parallel, you can order “matched and tagged” chain. Generally, if the conveyor chains are made in the same lots, the relative differences in length will vary only slightly. Table 2.5 shows the amount of variation for sev- eral types of chain chosen at random from the same production run. If your specific application requires less variation than those listed in Table 2.5, consider matched and tagged chains as an effective solution.
Table 2.5 Conveyor Chains Chosen at Random from Same Production Lot
Center Distance
Matched Tolerance
Less than 7 m
Less than 3 mm Less than 4 mm Less than 5 mm
7 ~ 15 m 15 ~ 22 m
2.3.7 Take-Up Conveyor chains need proper tension, which is why take-up is added to a sys- tem. You have to position take-up where the chain’s tension will be minimal. If you can remove two links from the chain, the adjusting length of take-up is: L = chain pitch + spare length If you can’t remove links from the chain, use this formula: L = length of machine 3 0.02 + spare length In this formula, 0.02 represents the allowable wear value (2 percent). There are two portions of the spare length: one is the maximum and minimum range of variation in length for new chains; the other portion is the length to loosen the chain’s connecting link when the chain’s total length has been set as tight as possible. For example: the machine length is 10 m, the length for maximum and minimum range of variation is 0.25 percent, assuming the length needed to connect chain is 25 mm, then: L = 10,000 3 (0.02 + 0.0025) + 25 = 225 + 25 = 250 (mm)
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