Sliding gate valves are true all-rounders in the valve technology field and can be used for high-precision control purposes in the fields of natural gas applications, combustion and firing installations, and burner applications. The sliding gate valves from Schubert & Salzer Control Systems have successfully passed the DVGW (German Technical and Scientific Association for Gas and Water) testing according to DIN EN 16678.
Thanks to their special design, which consists of two slotted discs sliding on and sealing against each other, sliding gate valves combine high control accuracy for gas flow with near-zero leakage. Furthermore, the central throttle element, represented by the slotted discs sliding on each other, is subject to little wear so that long service life can be acieved even under extreme conditions.
Thanks to different versions designed with different materials, and the possibility of being combined with all common positioners, the valves can be used in almost all areas of gas processing, distribution and utilisation. For years, the sliding gate valves had a DVGW certification according to the DIN 3394, but, due to the updated regulations of DIN EN 16678 (safety and control devices for gas burners and gas burning appliances), sliding valves have been re-examined by the DVGW and granted the new certification.
The certification covers type GS1 sliding gate valves with both pneumatic diaphragm and pneumatic piston actuator. Consequently, all sliding gate valves of the 8021, 8043 and 8044 series are covered by the new DVGW certification.
The maximum systemic control stroke of a sliding gate valve amounts to only 8 mm. This very short stroke ensures an opening and closing time of 100 ms for the entire stroke at a resolution of 0.1% of the stroke position. This very high dynamic not only improves the regulation quality, but it also forms the basis for control circuits with very short reaction times. This has proven the key to precision and therefore highly economic gas control functions. Sliding gate valves are manufactured with the current DVGW certification in the sizes DN 15 to DN 150, for pressures up to PN 40 and for fluid temperatures from -60 to 350°C.
Top-mounted positioner with optional Ex certification
In addition to the type 8047 analog, electro-pneumatic positioners, Schubert & Salzer Control Systems also offers the 8049 digital positioner, which allows the positioning of these pneumatically driven controllers to be performed. Both the 8047 and the 8049 positioner are top-mounted. This means that the positioner is mounted in a centred position on top of the valve actuator and so does not require additional space on the side. Furthermore, this very compact design keeps all moving parts inaccessible, which maximises operational safety.
If needed, both the 8047 analog, electro-pneumatic positioner (also in the intrinsically safe Ex II2G EEx ib IIC T6 version) and the 8049 digital, electro-pneumatic positioner (in the two wire version, also applying the IS protection class according to ATEX II 2 G Ex ia IIC T3/T4) can be combined with the DVGW certified control valves.
Thanks to the DVGW certification according to the new DIN EN 16678, the sliding gate valve with its numerous advantages can keep being used as a certified component for gas installations, natural gas applications, combustion and firing installations, or burner applications.
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