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Inspection procedure
- Inspection
- Inspection must be conducted as prescribed inTable 1
Table 1 (JIS standards correspondence)
| Inspection item | Inspection method | Standard | Remarks | |
|---|---|---|---|---|
| Size and exterior inspection | (1) Exterior inspection | 1) Check for any scratch or damage on the product 2) Check if the plate is without any peeling 3) Check the direction of the port and cushion 4) Check if the RODEND and BELLOWS are attached 5) Check if other accessories are attached |
No visible defect(when checked with the naked eye) | – |
| (2) Size inspection | Check if the size is as drawn in the plan (job order). (Especially parts A and W) Check the administration(distance moved) and the minimum and maximum value. Check the attachment. |
제The size of the product shall be inspected as prescribed in the approved plan (job order). The tolerance of the stroker must follow the prescribed standard. Standard (Table 4 – rank A) |
Table 4 of the tolerance for strokers was used Refer to (KS B 6370) |
|
| Performance evaluation | (1) No load operation test | The piston shall perform reciprocal movement in both directions to the head and to the rod under standard pressure (as stated in the plan). Operate the cylinder under no load at least 10 times |
The piston must stay within the stroke range without stopping during its operation. | – |
| (2) Minimum pressure operation test | The piston shall perform reciprocal movement in both directions to the head and to the rod under standard pressure (as stated in the plan). Operate the cylinder under no load at least 10 times |
The piston must stay within the stroke range without stopping during its operation. | Refer to Table 2 (KS B6370) for the minimum pressure | |
| (3) External leakage test | Apply the following pressure to both sides of the cylinder ports on the head and the rod. – Pressure: TEST pressure (as designated on the plan) – Holding time 5 min (applied to both the cylinder on the head and the rod) |
There should be no leakage from anywhere on the cylinder (when checked with the naked eye). | – | |
| (4) Internal leakage test | Apply the following pressure to both sides of the cylinder ports on the head and the rod, and check the amount of oil leaked by installing an oil leakage measuring gauge on the opposite side to which the pressure is being applied. – Pressure: TEST pressure (as designated on the plan) – Holding time 10 min (applied to both the cylinder on the head and the rod) |
The oil leakage after 10 minutes of holding time must not exceed the standard amount. Standard amount – (Table 3) | Table 3 for the amount of internal leakage allowed was used. Refer to (KS B 6370) |
|
| (5) Cushion operation test | Adjust the cushion valve and check if it is locked. Check the status of the cushion for the last 20 -35mm of the administered movement after applying standard pressure in both directions under no load. | The piston should drastically slow down when passing through the cushion part. The cushion part should be easy to adjust. (Check with the naked eye) |
Applied to cushion types only None cushion type is exempted |
|
- Table 2
- Minimum pressure for operation (unit: f/㎠) standard pressure 140 kgf/㎠
| When applying pressure from the head side | When applying pressure from the rod side | ||
|---|---|---|---|
| Rod diameter A | Rod diameter B | Rod diameter C | |
| Designated pressure X 4% (5.6kgf/cm) |
Designated pressure X 8% (11.2kgf/㎠) |
Designated pressure X 5.7% (7.84kgf/㎠) |
Designated pressure X 5% (7kgf/㎠) |
- Table 3
- Amount of internal leakage (unit:ml/10min)
| TUBE bore | Leakage amount | Bore (PISTON bore) | Leakage amount |
|---|---|---|---|
| ø40 | 0.3 | ø140(150) | 3.0 |
| ø50 | 0.5 | ø160 | 5.0 |
| ø63 | 0.8 | ø180 | 6.3 |
| ø80 | 1.3 | ø200 | 7.8 |
| ø100 | 2 | ø224 | 10.0 |
| ø125 | 2.8 | ø250 | 11.0 |
Table 4
| Stroker length permissible tolerance (unit: mm) | Cut processed goods normal tolerance (unit: mm) | ||
|---|---|---|---|
| CYL’STROKE / range of permissible tolerance | Permissible tolerance | Size/range of permissible tolerance | Permissible tolerance |
| Rank A | Intermediate rank | ||
| Below 100 | 0 ~ + 0.8 | 0.5~6 | ±0.1 |
| Above 100 and below 250 | 0 ~ + 1.0 | 6~30 | ±0.2 |
| Above 250 and below 630 | 0 ~ + 1.25 | 30~120 | ±0.3 |
| Above 630 and below 1000 | 0 ~ + 1.4 | 120~400 | ±0.5 |
| Above 1000 and below 1600 | 0 ~ + 1.6 | 400~1000 | ±0.8 |
| Above 1600 | 0 ~ + 1.8 | 1000~2000 | ±1.2 |
| 2000~4000 | ±2 | ||