JASH C.I. Lapping Plates are extensively used for accurate hand lapping of ferrous & non-ferrous parts to obtain a perfect oil tight surface.
Salient Features
- Made from close grained plain cast iron conforming to grade FG: 220 of IS: 210 (equivalent to GG20 / FT20 / 30-A). Higher grades also offered on request.
- Castings stress relieved to relieve internal stresses.
- Hand scraped surface finish.
- Offered in square, rectangular and round sizes.
- Constructional features of square and rectangular sizes similar to those of Cast Iron Surface Plates as per IS: 2285.
- Plates up to 630 x 630 mm provided with handles for lifting. Larger plates provided with cored holes in peripheral for lifting by mechanical means.
- Provided with 3 x 3 mm groves at a nominal pitch distance of 25 to 30 mm on top surface.
- Supplied with rexine cover for top surface protection.
Standard Sizes of Lapping Plate
| Square & Rectangular sizes ( L & B ) | Flatness accuracy in microns | Round Sizes (Diameter) | Tolerances on overall deviation from flatness in microns. |
||
|---|---|---|---|---|---|
| Sizes in mm | Grade 0 | Grade 1 | Sizes in mm | Grade 0 | 1 |
| 250 x 250 | 4 | 7 | 100 | 5 | 12 |
| 400 x 250 | 4 | 8 | 150 | 5 | 13 |
| 400 x 400 | 5 | 9 | 200 | 5 | 13 |
| 630 x 400 | 5 | 10 | 250 | 6 | 14 |
| 630 x 630 | 5 | 10 | 300 | 6 | 14 |
| 1000 x 630 | 6 | 12 | 400 | 7 | 16 |
| 1000 x 1000 | 7 | 14 | 600 | 7 | 16 |
