testing of the chain

• Before the start of the chaining work to measure horizontal distance, it is necessary to insure that chain is of correct length.

• A chain may either be tested with reference to a standard chain or with reference to steel tape.

• Sometime chain is compared with a permanently establish gauge as shown in fig below

Adjustment of chain

Chain are adjust in following way

1) When chain is too long it is adjusted by

a) Closing up the joint of the ring.

b) Hammering the elongated ring.

c) Replacing some old ring by new ring.

d) Removing some of the ring.

2) When chain is too short it is adjusted by

a) Straightening the bent link.

b) Opening the joint of the ring.

c) Replacing some old ring by new ring.

d) Inserting new ring where necessary.