Danfoss DSV 2 3-way change-over (double stop) valve, code 148F3006, Change-over valve, DSV 2, Weld flange. DSV 1 and DSV 2 are 3-way change-over (double stop) valves designed for industrial refrigeration plant. They are used with double safety-valve systems: the change-over valve isolates one of two parallel safety relief valves so it can be inspected or replaced while the second valve keeps the vessel protected, without shutting down the plant. The valve cone gives perfect closing even at minimum torque, accepts flow in both directions and is easy to dismantle for servicing. Housing and bonnet are special cold-resistant (low-temperature) steel meeting the Pressure Equipment Directive and international classification-authority requirements; a Teflon tightening ring seals the cone and the polished stainless-steel spindle runs in an O-ring seal. All valves carry a vented cap and nipple/flange connections that permit easy inspection or replacement of the safety valves, and are prepared for seal-wire sealing to prevent unauthorised operation. Applicable to HCFC, non-flammable HFC, R717 (ammonia) and R744 (CO2). Maximum operating pressure 40 bar g (580 psig); temperature range -50 to +100 C (-58 to +212 F). When fitted with the matched pair of safety valves the assembly meets EN 13136 (max 3% pressure drop in the upstream line). This code has inlet connection Weld flange, 20 mm (3/4 in) and outlet G-type, 3/4 in; the two safety-valve branch connections are Weld nipples, 20 mm (3/4 in), EN 10220 and the matched safety-valve pair is 2 x SFA 15. Nominal bore DN 32 (1 1/4 in); Kv 30 m3/h (Cv 34.8 gal/min); maximum working pressure 40 bar g (580 psig); media temperature -50 to 100 C (-58 to 212 F). PED 2014/68/EU conformity assessment Art. 4, par. 3, fluid group I. Specifications per Danfoss store code 148F3006.