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5 Year Warranty
542F_With_Drain_Plug_SafetyValve_DN40_Nabic_RedBG_v1-copy.jpg 542F_With_Drain_Plug_SafetyValve_DN40_Nabic_RedBG_v2-copy.jpg 542F_With_Drain_Plug_SafetyValve_DN40_Nabic_RedBG_v3-copy.jpg 542F_With_Drain_Plug_SafetyValve_DN40_Nabic_RedBG_v4-copy.jpg

Fig 542F Safety Relief Valve

5 Year Warranty

The NABIC Fig 542F is an extremely versatile flanged valve and although designed primarily for the protection of hot water boilers, its wide range of applications make it an ideal general purpose safety valve.

All wetted parts are manufactured from dezincification resistance materials. Designed and tested to BS EN ISO 4126 -1. Approved for use on applications requiring WRAS.

  • Resilient PTFE seating design
  • Easy inspection and cleaning
  • 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: DN32 - DN80

Pressure: 0.3 - 10.5 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
  • Pressure setting locked and sealed
  • Drain plug fitted on sizes DN40 and above allows fitting of a pressure gauge


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 (Not shown) 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

Dimensional Drawing

NABIC Fig 542F

Dimensions & Weights

Inlet Rp BSP
32 Flanged 1 1/4" 46 60 180 3.00
40 Flanged 1 1/2" 54 64 225 4.40
50 Flanged 2" 64 73 263 7.15
65 Flanged 2 1/2" 76 83 303 10.00
80 Flanged 3" 90 96 366 16.41


Downloads +
Discharge Capabilities +

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