HELI CQD16X1, Operation & Service Manual

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4) avoid over tight contacting of roller in the chain;
5) realize smooth moving of lifting chain;
6) reduce the tensity of lifting chain.
4.8.14 Check the lifting chain
Measure the wear of lifting chain with tape.
4.8.14.1 Determine the pitch of lifting chain
1) Lift the fork by 152mm.
2) Choose the chain pitch bypassing pulley during operation.
3) Measure the center distance between two chain pin of outer chain plate, that is
the pitch of lifting chain.
4) Find the pitch value in the table 1 and then determine the pitch number.
5) Find the pitch number required in table 1 on the chain.
6) Measure from the center of first chain pin to the center of last one.
Note : pitch is the distance between the chain pins.
7) Calculate the elongation(%) of lifting chain.
Elongation of lifting chain %=[measured length /(newly lifting chain
length/100)]-100
Example: the lifting chain pitch is 25mm. Table 1 shows that “newly chain length”
corresponding lifting chain pitch is 305mm. The measured length by tape is 309mm.
X=[309/(305/100)]-100
X=309mm/3.05-100
X=101.3-100
X=1.3
In the example, the elongation of lifting chain is 1.3%.
8) if the elongation exceeds 3% or it will exceed 3% before next maintenance,
please change the lifting chain. Refer to table 4-8-1.
It is forbidden to repair the lifting chain through changing the worn pitches.