Valve with a delta P-function and flow limiting function

A device for regulating and controlling flow in a heating and cooling system, the device comprising:

• a complete valve body (1) with an inlet (2) and an outlet (3), first and second valve functions being mounted in the valve body, the first function in a flow direction is a difference pressure valve (5) with a seat (7) and a plug (8) and the second function in the flow direction is a flow control valve (6) with a seat (11) and a plug (18),
• an intermediate chamber (4) being arranged between the first and the second valve functions,
• first and second measuring nipples (27b, 27a) being mounted in the valve body for registering first, second and third static pressures (P1, P2, P3),
• the valve body being controlled, depending on the second and the third static pressures (P2, P3), to generate a required pressure difference between the second and the third static pressures (P2, P3), and a magnitude of the required pressure difference is primarily set by a spring (36), the spring being adjustable during operation, the spring (36) biases a membrane (31) which, in turn, influences axial movement of the plug (8) such that, during operation, a pressure level between the plug (8) and the seat (7) of the difference pressure valve (5) is throttled from the first static pressure (P1) to the second static pressure (P2), to provide conditions for the flow control valve (6) to work with the required pressure difference between the second static pressure (P2) and the third static pressure (P3),
• a level of the third static pressure (P3) in the outlet (3) is in contact, via at least one channel (55) with a space between the membrane (31) and a top part (20) in the valve body (1), all of the first static pressure (P1) at the inlet (2) of the valve body, the second static pressure (P2) in the intermediate chamber (4) and the third static pressure (P3) after the flow control valve (6) in the outlet (3) of the valve body are measured and registered via the first and the second measuring nipples (27a, 27b),
• both of the first and the second static pressures (P1, P2) being registered in the second measuring nipple (27b) whereby the registration of the first static pressure (P1) presumes that either the flow control valve (6), or another separate valve after the valve body, is closed, or that a flushing spindle in the difference pressure valve (5) is open, whereby a common pressure level is obtained on both sides of the membrane (31) which facilitates adjustment of the spring (36) such that the plug (8) opens in relation to the seat (7) of the difference pressure valve and a passage is opened from the inlet (2) into the intermediate chamber (4) such that the first static pressure (P1) is provided also in the intermediate chamber and consequently, via a first signal channel (25), in the valve body (1) upwards to the second measuring nipple (27b) while the third static pressure (P3) after the control valve (6) leads to the first measuring nipple (27a) via a second signal channel (26) in the valve body (1) from the outlet side (3) to the first measuring nipple (27a);
• the complete valve is mounted in a tube system which is flushable, during operation, and because the flushing spindle, mounted in a center section (37) with an inner channel (81) of a lower part (83), is moved along the inner channel (81) of the lower part (83) until an end plane (43) of the central part (37) to open a passage for the medium from the intermediate chamber to flow, via either a hole or slots (44) in the central part (37), to out into a space where the spring (36) is mounted, whereby the second static pressure (P2), which is provided in the intermediate chamber (4), is obtained on both sides of the membrane (31) and a spring force of the spring (36) biases the plug (8) from the seat (7) of the difference pressure valve such that the difference pressure valve (5) is positioned to facilitate the flow of medium and flushing through of the tube system.