5 Year Warranty
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Fig 520 High Lift Safety Valve

5 Year Warranty
Buy Online Price from £2,035.68 (ex vat)

The NABIC Fig 520 flanged valve has been designed primarily for use on unvented hot water Heating systems, where a high capacity, emergency steam relief capability is required.

All wetted parts are manufactured from dezincification resistance materials. Designed and tested to BS EN ISO 4126 -1. 

  • Resilient PTFE seating design
  • Separate outlets reduce effects of back pressure
  • High discharge capacity
Pressure Equipment Directive - PED 2014/68/EU
Product Features +

Medium: Hot water, steam, compressed air and inert gasses, Co2 (to 20°C), ethylene glycol, potable water

Size Range: DN65 - DN100

Pressure: 0.4 - 12.5 bar

Material: Gunmetal

Temperature: -20 to 195°C

Connection: Flanged inlet & screwed outlet

Pipe Connections

Flanged inlet connections. Threaded female outlet connections, Rp (BSP) parallel to BS EN 10226-1. Most flange standards can be accommodated.


All valves are shell and seat tested (to confirm set pressure) before leaving the factory and all valves are supplied pre-set with a tamper proof seal. Pressure Test Certificate and Letters of Conformity available on request.

Product Extras

  • Available with Viton seat design
  • Padlock available (complies with M&E3)
  • Pressure setting locked and sealed
  • Drain plug fitted on all sizes


Ref No Name of Part Material
1 Thrust Washer Brass, BS EN 12164 CW609N
2 Grubscrew Steel
3 Test Lever Brass, BS EN 1982 CC754S
4 Spring Chrome Vandium Alloy Steel, BS 2803 735 A50 HS (Stainless Steel, BS 2056 302S26 Opt)
5 Label Yellow kapton
6 Spring Cover Bronze, BS EN 1982 CC491K
7 Piston Brass, BS EN 12164 CW609N
8 Diaphragm Silicon Rubber
9 Seat Seal Holder Bronze, BS EN 1982 CC491K / Brass BS EN 12164 CW602N (DZR)
10 Seat Seal PTFE (Viton Opt)
11 Starlock Washer Stainless Steel
12 Body Bronze, BS EN 1982 CC491K
13 Lever Pin Steel
14 Lead Seal Lead
15 Adjusting Screw Brass, BS EN 12164 CW609N
16 Spring Plate Brass, BS EN 12164 CW609N
17 Spindle Brass, BS EN 12164 CW721R
18 Seat Seal Retaining Plate Bronze, BS EN 1982 CC491K / Brass BS EN 12164 CW602N (DZR)
19 O-Ring Viton
20 Seat Bronze, BS EN 1982 CC491K
21 Seat O-ring Viton
22 Drain Plug Brass, BS EN 12164 CW609N


Dimensional Drawings

NABIC Fig 520 Dimensional Drawing

Dimensions & Weights

Inlet Ro BSP
65 Flange 2" 40 350 152 175 64 1/4"
80 Flange 2 1/2" 50 390 166 195 76 1/4"
100 Flange 3" 65 480 205 210 90 3/8"


Downloads +
Discharge Capabilities +
Buy Online +

Fig 520 High Lift Safety Valve

To order these products please call us on +44 (0)1462 443 278. 

Part Number Size Ex Vat Stock Status More
DN65 £ 2,035.68 Call us - 01462 443 278 +
65mm Flanged Inlet x Two 2" BSPP Female Outlets to BS21 - PTFE to Metal Seat
DN80 £ 2,726.65 Call us - 01462 443 278 +
80mm Flanged Inlet x Two 2.1/2" BSPP Female Outlets to BS21 - PTFE to Metal Seat
DN100 £ 3,497.95 Call us - 01462 443 278 +
100mm Flanged Inlet x Two 3" BSPP Female Outlets to BS21 - PTFE to Metal Seat

What our customers say

The reason I went to NABIC was because we have to meet certain water regulations. After a chat with Northumbrian Water, they suggested looking into NABIC products as they are WRAS approved and suitable to use on all potable water applications.

I went direct and bought 4 pipe interrupters with next day delivery, which have been installed in our on-site laboratory. My user experience was great and I liked the fact that site has all the necessary specifications and prices easily to hand.

Peter Bauckham - Managing Director, Argos Inspection

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