The ball valves for safety applications, as well as the related accessories and adapters, are suitable for the same fluids, belonging to Groups 1 and 2, indicated in the paragraph “Compatible fluids” of the SV series safety valves. These include: air, nitrogen and refrigerants, in the physical state of gas or vapour classified by Article 13, paragraph 1, letter (a) and letter (b), of PED Directive 2014/68/EU as belonging respectively to Group 1 and 2, with reference to Regulation (EC) No 1272/2008 and in accordance with the safety classification A1, A2L in Annex E of the standard EN 378-1: 2016. Refrigerant fluids are an example:
– HFC R32, R134a, R404A, R407C, R410A, R507;
– HFO R1234yf, R1234ze and HFC / HFO, R448A, R449A, R450A, R452A, R452B, R445A, R454B, R454C, R513A blends.
It is also possible to use these safety valves with HC (hydrocarbon) refrigerants such as:
– R290, R600, R600a, R1270;
belonging to Group 1, as defined by Article 13, paragraph 1, letter (a) of the PED Directive 2014/68/EU, with reference to Regulation (EC) No 1272/2008 and in accordance with the safety classification A3 in Annex E of the EN 378-1:2016 standard.
The body of the ball valves for safety applications and the chromed ball are made entirely of hot forged brass UNI EN 12420 – CW617N. The TIG welding between the body and the sleeve and the HNBR compound sealing O-rings, placed on the operating spindle, ensure perfect hermetic sealing of the valve, while the sealing gaskets on the ball, in special modified PTFE, guarantee low operating torques. The design of the tap is such to ensure the internal balancing of the pressures with the valve closed and to avoid the danger of expulsion of the operating spindle. This is in treated steel and the relative locking pin is in stainless steel. The adapters are entirely made of UNI EN 12420 – CW614N brass.
The installation must assist in the connection of the safety valves to the system, and therefore the same considerations apply.