2-way cartridge клапаны , pressure limiting Функции LFA.DBW…E

Description Type-examination tested safety valves according to Pressure Equipment Directive 2014/68/EU Size 32 … 63 Component series 7X Maximum operating pressure 420 bar Maximum flow 5000 l/min Size 32 … 63 Component series 7X Features Installation bore according to ISO 7368 (main pressure relief valve) Response pressure 50 to 420 bar Additional directional valve connection surface, optional adjustment types, optionally: - Hexagon - Rotary knob Valve mounting set (sealable) as accessories Product description Type-examination tested safety valves type LFA . DBW…E according to Pressure Equipment Directive 2014/68/EU are pilot-operated 2-way cartridge valves in seat design with set relief pressure setting p max. The complete valve generally consists of one cartridge valve (1) for installation bores according to ISO 7368 and one respective control cover (2) with integrated sealed pressure limitation unit (4). Version “DBW” offers a connection possibility closed by a cover plate (8) for a directional valve with porting pattern according to ISO 4401-03-02-0-05. By attaching a suitable directional valve at the position of the cover plate, an additional function like "depressurized start-up” can be realized. The use of this additional function requires a special set-up of the overall circuitry in order to maintain compatibility with the Pressure Equipment Directive 2014/68/EU. The factory nozzle fitting (9) (“X”, “F”, “P”) as well as the installed compression spring (10) must not be changed. The installation position (“D”) is not fitted. The cartridge valve (1) is designed as seat valve without area difference. The relief pressure effective at port A is directed to the spring chamber (6) of the cartridge valve (1) and to the pressure limitation unit (4) via channel X (5). The piston sealing (7) prevents an internal leakage from the spring chamber (6) to port B and thus increases the operational safety by avoiding gap filtration. Under the pressure value set at the pressure limitation unit (4), the spool (3) is pressure-compensated and remains closed in a seat-tight manner due to the spring force of the compression spring (10). The pressure equilibrium at the spool (3) is only changed when the relief pressure at port A is reached, namely by opening the pressure limitation unit (4), so that excessive hydraulic fluid directly flows to channel B via the spool (3) and the pressure in A is limited to the set pressure value. The pressure limitation unit (4) is optionally available with rotary knob. This allows for a manual reduction of the pressure adjustment without changing the relief pressure setting. This simplifies a regular functional test. Type code 01 02 03 04 05 06 07 08 LFA DBW – 7X / E 01 Control cover LFA 02 Size 32 32 Size 40 40 Size 50 50 Size 63 63 03 Pressure limiting function with connection surface for directional valve DBW Adjustment types 04 Rotary knob 1 Hexagon 2 05 Component series 70 ... 79 (70 ... 79: unchanged installation and connect