13.1
Where tubulars, sockets and fitting are required to be galvanized, the zinc coating shall be done in accordance with IS 4736 and the requirements as given in 13.1.1 to 13.1.4.
Figure description:
FIG. 1 MECHANICAL EXPANSION TEST ON SOCKETS
Key Information:
- Subject: Technical diagram of a mechanical expansion test setup for sockets.
- Key Entities:
- Socket: Vertical cylindrical component shown in cross-section (hatched area.
- Expansion Tool/Mandrel: Central vertical component inserted into the socket.
- Support Structure: Two large, curved base components flanking a central square block marked with an "X".
- Units: All dimensions are in millimetres.
FIG. 1 MECHANICAL EXPANSION TEST ON SOCKETS
Table 31 Dimensions of Taper Screw Plugs for Expansion Test
(Clauses 11.2.2.4 and 11.2.2.5)
All dimensions in millimetres.
| Nominal Bore (2) | Gauge Diameter (3) | Threads per 25.4 (4) | Tolerance on Total Number of Threads (5) | A (6) | B (7) | C (8) | D (9) | |
|---|---|---|---|---|---|---|---|---|
| i) | 6 | 9.728 | 28 | 2 | 1.8 | 13 | 11 | 7 |
| ii) | 8 | 13.157 | 19 | 2 | 2.8 | 19 | 13 | 10 |
| iii) | 10 | 16.662 | 19 | 2 | 2.8 | 19 | 16 | 13 |
| iv) | 15 | 20.955 | 14 | 2 | 3.6 | 25 | 19 | 14 |
| v) | 20 | 26.441 | 14 | 2 | 3.6 | 25 | 29 | 17 |
| vi) | 25 | 33.249 | 11 | 2 | 4.6 | 32 | 29 | 21 |
| vii) | 32 | 41.91 | 11 | 2 | 4.6 | 32 | 32 | 27 |
| viii) | 40 | 47.803 | 11 | 2 | 4.6 | 32 | 38 | 32 |
| ix) | 50 | 59.614 | 11 | 2 | 4.6 | 32 | 38 | 37 |
| x) | 65 | 75.184 | 11 | 2 | 4.6 | 32 | 51 | 48 |
| xi) | 80 | 87.884 | 11 | 2 | 4.6 | 32 | 57 | 54 |
| xii) | 100 | 113.03 | 11 | 2 | 4.6 | 32 | 64 | 70 |
| xiii) | 125 | 138.43 | 11 | 2 | 4.6 | 32 | 67 | 76 |
| xiv) | 150 | 163.83 | 11 | 2 | 4.6 | 32 | 70 | 89 |
13.1.1 Mass of Zinc Coating
Mass of zinc coating shall be determined before threading on full length test piece in case the length of the fittings are less than 100 mm and on 100 mm length in case of the fittings are more that 100 mm in accordance with IS 4736 and shall not be less than 360 g/m².
13.1.2 Uniformity of Zinc Coating
The test for uniformity of zinc coating shall be done on full length fittings in case the length of the fittings are less than 100 mm and on 100 mm length in the length of the fittings are more 100 mm in accordance with IS 2633 and shall withstand 5 one minute dips.
13.1.3 Adhesion Test
The adhesion of zinc coating on fittings shall be determined by pivoted hammer test in accordance with IS 2629.
13.1.4
The zinc coating shall be reasonably smooth and free from such imperfections as flux, ash and dross inclusions, bare patches, black spots, pimples, lumpiness, runs, rust stains, bulky white deposits and blisters.
13.1.5
Tubulars, sockets and fittings shall be galvanized before screwing.