RDR MK, shutter valves for the conservator oil pipe, DN25–DN80
The RDR MK are shutter valves for the oil pipe between the conservator and the transformer tank, in nominal sizes DN25, DN50 and DN80. On a sudden movement of oil the valve closes the pipe and stops oil draining from the conservator toward the point of damage.
- Standard
- IEC 60076-22-1
- Nominal size
- DN25, DN50, DN80
- Contacts
- 2 changeover reeds; 24–230 V AC/DC; 2 A
- Breaking capacity
- 250 W DC (L/R < 40 ms); 400 VA AC (cos φ > 0.5)
Price, availability and lead time on request. We help with analogue selection, customs clearance and delivery.
Description
When the transformer tank is damaged or the oil pipe is torn, oil from the conservator keeps flowing down and spreads across the substation. The RDR MK shutoff valve is installed in the pipe between the conservator and the tank. A sudden movement of oil closes the flap instantly. The volume of oil reaching the fault location is limited, and with it the risk of soil contamination and, in severe cases, of explosion and fire.
Such valves are needed most in seismic zones and hurricane areas, where equipment displacement tears pipelines. The RDR MK works with mineral and silicone oil, in new installations and upgrades, at coastal and offshore sites. The body and the top part with the terminal box are cast from aluminum with a RAL 7032 powder coating, and the offshore version is supplied unpainted with a special surface treatment. The installation direction is shown by a red arrow on the body.
The valves are made in DN25, DN50 and DN80 with flanges for M12 or M16 studs. The design includes a drain valve, an inspection window, a reset lever, a mechanical test button and a mechanism for adjusting the flow trip threshold. The seals are NBR or Viton. The ambient temperature is from −40 to +80 °C and the oil temperature from −40 to +115 °C. The degree of protection is IP65 to EN 60529, corrosion protection is C4-M or C5-M, and the standard is IEC 60076-22-1.
The flap position is signaled by two protected reed changeover contacts rated 24–230 V AC/DC and a current up to 2 A. The minimum switching current is 10 mA at 24 V DC, and for lower currents gold-plated contacts are fitted. The breaking capacity is 250 W on DC at L/R < 40 ms and 400 VA on AC at cos φ > 0.5. The dielectric strength is 2.5 kV AC for 1 min between the contacts and earth and 1.0 kV between open contacts. The trip signal goes into the transformer protection circuit together with the signals of the gas relay and the level indicator.
Technical specifications
| Standard | IEC 60076-22-1 |
|---|---|
| Nominal size | DN25, DN50, DN80 |
| Contacts | 2 changeover reeds; 24–230 V AC/DC; 2 A |
| Breaking capacity | 250 W DC (L/R < 40 ms); 400 VA AC (cos φ > 0.5) |
| Insulation | 2.5 kV AC 1 min |
| Oil temperature | −40…+115 °C |
| Degree of protection | IP65 |
| Seals | NBR, Viton |
| Options | flow threshold adjustment, mechanical test button, reset lever |
Replacement for
no direct designation under GOST; conservator oil pipe shutoff valves (general type)
selected by purpose and main parameters, please confirm with our manager
Request a price and lead time
RDR MK, shutter valves for the conservator oil pipe, DN25–DN80. We reply within one business day.
Or email sales@usk.ua or call 044 339-50-20.
Customs codes
| UKTZED (Ukraine) | 8481 80 99 00 |
|---|---|
| HS, 6 digits | 8481 80 |
| CN (EU) | 8481 80 99 |
| HTSUS (USA) | 8481 80 90 50 |
| China customs tariff | 8481 80 40 90 |
Codes are for reference: the final code is determined at declaration for the specific model.
Questions and answers
Which oil pipe diameters is the RDR MK made for?
In nominal sizes DN25, DN50 and DN80 with flanges for M12 or M16 studs.
What are the parameters of the valve signal contacts?
Two reed changeover contacts for 24–230 V AC/DC and up to 2 A. The breaking capacity is 250 W DC at L/R < 40 ms and 400 VA AC.
Which oils and what temperature does the valve work with?
With mineral and silicone oil at an oil temperature from −40 to +115 °C. The ambient temperature is from −40 to +80 °C, and the degree of protection is IP65.
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