Transformer Oil Drain Device Type C2
The Oil Drain Device Type C2 is used for oil sampling or emptying the transformer tank. The device is welded into the transformer case. The device is designed for use together with connection pipe F DIN 42551 for draining the transformer case for regeneration purpose of the oil.
The Oil Drain Device Type C2 is designed in accordance with EN 50216-4:2015 Type C2 and IEC 60076-22-7 Type C2, similar to former DIN 42551 A.
The Oil Drain Device Type C2 is designed in accordance with EN 50216-4:2015 Type C2 and IEC 60076-22-7 Type C2, similar to former DIN 42551 A.
Transformer Oil Drain Device Type C2
- NW 22 / C2-A (former DIN 42551 A22)
- NW 31 / C2-B (former DIN 42551 A31)
- NW 40 / C2-C (former DIN 42551 A40)
Socket B of size NW22 and NW31 is produced by a deep-drawing process. This guarantees absolute leak tighntess. The stop plug is made of EN-GJL-200 grey cast iron (upon request in AISI 316 stainless steel), while the stop screw is made of brass. We offer the oil drain either as standard type (Type C2) or soft-sealing type (Type C2 OR). An O-ring is attached to the soft-sealing design for redundant sealing.
Oil Drain Device Type C2 OR
The Oil Drain Device Type C2 OR is a consistent development of the well-proved DIN 42551 and EN 50216-4. The built-in O-ring prevents accumulation of oil in the stop plug.The function of the connection pipe F DIN 42551 is completely preserved. The oil drain device type C2 OR is available in the same sizes like metal sealed 42551 A/Type C2 in accordance with DIN EN 50216-4. Advantage is the additionaly safety against leakage, as well as no oil in stop plug, which prevents contamination when the cap will be removed.
O-Ring Type C2 OR Standard Type C2
For measures and weights please see our info on data sheet.
| DN |
Rated Power (kVA) | Tightening torque screw and cap |
| 22 | ≤ 800 | 50 Nm |
| 31 | 800 < Sr ≤ 3150 | 60 Nm |
| 40 | > 3150 | 70 Nm |
Connection Pipe F in Accordance With DIN 42551
The connection pipe is a maintenance-tool to connect the oil drain device Type C2 / C2 OR to an extern oil-system. The connection pipe is manufactured in two sizes and can be reduced from NW 31 to NW 22 or from NW 40 to NW 31.
| Connection Pipe |
Nominal Width |
Thread d13 |
Thread d14 |
L1 | L2 | Z |
| F 22/31 DIN 42551 | 22 | M 48 x 1,5 | M 33 x 1,5 | 145 | 260 | 11 |
| F 31/40 DIN 42551 | 31 | M 60 x 2 | M 48 x 1,5 | 180 | 270 | 17 |
| F 31 DIN 42551 | 31 | M 48 x 1,5 | - | 145 | 260 | 17 |
| F 40 DIN 42551 | 40 | M 60 x 2 | - | 180 | 295 | 17 |
Accessory parts to connect tubes to the outlet:
- Reduction M60 x 2 to 1 ½" internal thread.
- Reduction M48 x 1,5 to 1" internal thread.
See below dowloads for further information.
