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DESCRIPTION :
The ball valves, shown in this chapter, are classified “Pressure accessories” in the sense
of the Pressure Equipment Directive 97/23/EC, Article 1, Section 2.1.4 and are subject of
Article 3, Section 1.3 of the same Directive. They are designed for installation on commercial
refrigerating systems and on civil and industrial conditioning plants, which use refrigerant fluids
proper to the Group II (as defined in Article 9, Section 2.2 of Directive 97/23/EC and referred
to in Directive 67/548/EEC).
The specific design of Castel ball valves :
- ensures the internal equilibrium of pressures when the valve is closed;
- permits the bi-directional flow of the refrigerant and, consequently, the assembly on the plant without taking into account the direction of the refrigerant;
- prevents any risk of ejection or explosion of the spindle.
The opening and closing of the valve is realized by turning the spindle one fourth of a turn. A
standstill in turning realizes either a full opening or a full closing, moreover the arrow printed on
the spindle head shows the flow direction. The electric welding of the bodies and the seal
gaskets, assembled on the spindle, prevent any leaks.
Ball valves are available in the following two types :
- Type 6590 (full port) and type 6591 (reduced port) without access fitting.
- Type 6590/A (full port) and type 6591/A (reduced port) with access fitting. These ball valves are equipped with valve core 8394/A and cap 8392/A.
The main parts of the valves are made with the following materials :- hot forged brass EN 12420 – CW 617N for body;
- hot forged brass EN 12420 – CW 617N, chromium plated, for ball;
- copper tube EN 12735-1 – Cu-DHP for solder connections;
- steel, with proper surface protection, for the spindle;
- chloroprene rubber (CR) for outlet seal gaskets;
- P.T.F.E. for seat ball gaskets;
- glass reinforced PBT for cap that covers the spindle. Hot forged brass EN 12420 – CW 617N for caps on sizes from 6590/M64A up to 6591/34A.
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