IS 2540 : 2008 Dimensions for Threaded Centre Holes
| ICS 25.080.01 | PGD 37 |
|
| Reaffirmed 2014 |
1 Scope
This standard prescribes the dimensions of threadedcentre holes with 60� countersink. Centre holes as perthis standard are meant for the assembly of pulleysand couplings with pressing tools, but not fortransportation with eyebolts. The forms of centre holesare functionally equivalent; hence the choice of formis left to the manufacturers.
2 References
The following standards are necessary adjuncts to thisstandard:
| IS No. | Title |
IS 1369 : Part 3 :
1995 | Fasteners -Thread run-outs and under-
cuts: Part 3 Dimensions for screw
thread run-outs and undercuts for
internal threads (Blind tapped holes)
(third revision) |
IS 2102 : Part 1 :
1993 | General tolerances: Part 1 Tolerances
for linear and angular dimensions,
without individual tolerance
indications (third revision) |
IS 10952 : 1984/
ISO 2306 : 1972 | Recommendations for drills for use
prior to tapping screw threads |
| IS 11668 : 1985 | Technical drawings - Simplified
representation of centre holes |