NABIC 500T Size Selection Guide

SIZE SELECTION GUIDE FOR THE NABIC 500T PRESSURE & TEMPERATURE RELIEF VALVE

NABIC FIG 500T “BORE” OR “CONNECTION” SIZE?

Care needs to be taken when ordering the NABIC Fig 500T Combined Pressure and Temperature Relief Valve.

The inlet connection is one thread size larger than the ‘nominal’ valve size. The inlet connection is a male taper thread. The larger size allows the temperature element to be fitted during production.

The outlet connection is a female parallel thread and is also one size larger than the nominal valve size, as per the standard NABIC Fig 500, to allow the valve to pass the certified discharge capacity as stated in our literature.

SELECTION EXAMPLE

When selecting a NABIC Fig 500T having a nominal size of DN32, the inlet thread size will be shown as 1.1/2” BSPT, i.e. one thread size larger than the nominal valve size, and a 1.1/2” BSPP for the outlet connection.

Nominal Valve (Bore) Size	Inlet Connection Male BSP Taper	Outlet Connection Female BSP Parallel
DN15	3/4"	3/4"
DN20	1"	1"
DN25	1.1/4"	1.1/4"
DN32	1.1/2"	1.1/2"
DN40	2"	2"
DN50	2.1/2"	2.1/2"