HPV Valve
The operating principle of HPV Hydraulic Valve is as follows: the fluid passes from the “inlet chamber” to the “intermediate chamber” through a hole in the cap and then through a dirt-proof filter. Then, it fills the “shutter chamber” through an orifice. Next, it reaches the solenoid valve holder block through a connecting hole. Inside the block the fluid finds two paths that run parallel to each other to reach the “discharge chamber”. The fluid undergoes to pressure drops along this path depending on the opening level of the orifices and on the opening of the valves. An intermediate pressure is established between the delivery pressure and the discharge pressure, as a result of these pressure drops in the “shutter chamber”. Together with the contrasting action of the spring, this pressure moves the axial position of the shutter, which, in turn, influences the upstream/downstream pressure values of the valve and therefore also the “shutter chamber” pressure. Consequently, the balance of the forces is further modified, which regulates the position of the shutter itself. This phenomenon ceases once the position of equilibrium is reached, where the effect of the pressure of the “shutter chamber”, added to the force of the spring, is equal to the effect of the delivery pressure.
The valve works according to three operating modes;
• Closed;
• Intermediate low flow position;
• High flow position.
The high flow position can, at worst, also coincide with the valve position completely open, but nonetheless it can be regulated to limit the capacity of the line. The high and low flow positions are regulated manually from the outside by means of needles for adjustment.
The flow adjustment by a digital valve occurs by a closed ring control carried out by a flow meter provided with an electronic register. The capacity can be regulated almost constantly along 0-100% range of the shutter opening. The HPV Hydraulic Valve is available both as a simple shutoff valve and in a digital version.
The valve can be supplied in two versions:
– With body in carbon steel.
– With body in aluminium.
Materials of the other components are common:
– Shutter in aluminium.
– Fixed parts in aluminium.
– Other details in stainless steel and/or carbon steel.
– The dynamic sealing ring of the energised type shutter in PTFE loaded carbon.
– Shutter seal packing in Viton on incorporated metallic core.
– The rest of the packing in Viton.
Operating temperature range | -20°C to 70°C (-4°F to 158°F) | |
Max kinematic viscosity | 40 cST | In the standard version |
Max operating pressure (steel body) | 10 bar (145 PSI) | Up to 70°C (158°F) |
Max operating pressure (aluminium body) | 10 bar (145 PSI) | Up to 70°C (158°F) – reduces to 5 bar (73 PSI) up to 125°C (257°F) |
Min. valve opening pressure | 0,09 bar (1.31 PSI) | |
Max pressure in no-return function | 1,5 bar (21.8 PSI) | |
Capacity coefficient | Cv 270 GPM/PSI | |
Max flow rate for 0,5 bar (7.3 PSI) pressure drop | 2500 l/min (660 GPM) | With diesel and gasoline (it decreases in proportion to the viscosity) |
Flanges | DN4″ – ANSI 150 B 16.5 RF SF | |
Closing time | < 4 sec. | Adjustable |
Opening time | From 3 to 6 sec. | Adjustable |