Schlumberger B42R Gas Pressure Regulator

Schlumberger B42R Gas Pressure Regulator is an internal-relief, spring-loaded regulator designed for residential and light commercial gas service, featuring a 3/4 in. NPT inlet and 1 in. NPT outlet. As the internal-relief variant of the B42 Series, it includes a built-in relief path to vent excess downstream pressure and protect downstream equipment. The regulator has a cast-iron body with NPT ports for straightforward installation in gas lines, and is commonly used to regulate natural gas pressure feeding burners, appliances, and small commercial gas lines to maintain a stable downstream pressure. It is marketed within the Actaris / Schlumberger family of regulators and supports capacity ratings for 0.6 SG gas at standard base conditions, with official spec sheets detailing its use in residential and light-commercial service and noting the internal-relief option. This combination of rugged construction, standard NPT connections, and an integrated relief mechanism makes the B42R a typical drop-in choice for gas-regulation applications where consistent downstream pressure is essential.