Degree of Accuracy in chaining
- The degree of accuracy in chaining is expressed as a ratio called the chaining ratio.
- Eg: If the error is 0.25m during the measurement of total length of 500m.
- R = 0.25/500 = 1/2000
Adjustment of chain
A. When the chain is too long, it is adjusted by:
- Closing up the joints of the ring
- Hammering the elongated rings.
- Replacing some old rings by new rings and
- Removing some of the rings
B. When the chain is too short, it is adjusted by:
- Straightening the bent ends
- Opening the joints of the ring.
- Replacing the older ring by some larger ring.
- Inserting new rings where necessary.