Steam pressure reducing valve working princple and installation matters

Steam pressure reducing valve working principle and installation matters

The steam pressure reducing valve is suitable for water, steam and air medium pipelines. By adjusting the inlet pressure to a certain required outlet pressure, when the inlet pressure and flow rate change, the outlet pressure is automatically maintained within a certain range by the energy of the medium itself. Internal, but the difference between the inlet pressure and the outlet pressure must be ≥0.2MPA/CM.

The working principle of the steam pressure reducing valve is to reduce the inlet pressure to a certain required outlet pressure through the throttling of the opening and closing member, and to keep the outlet pressure stable. When the steam pressure reducing valve is shipped from the factory, the adjusting spring is in an uncompressed state. At this time, the main valve flap and the valve flap are closed. When using, turn the adjusting screw clockwise, compress the adjusting spring, and move the diaphragm to open the valve flap. The medium enters the piston from the hole through the valve seat to the b hole. Under the action of the medium pressure, the piston moves downward to push the main valve disc away from the main valve seat, so that the medium flows to the valve. At the same time, the hole from the c enters the diaphragm. When the pressure behind the valve exceeds the set pressure, the diaphragm is pushed up to compress the adjustment spring, and the valve flap is moved in the closing direction, so that the medium flowing into the piston is reduced, and the pressure is also increased. When the main valve flap is pushed up and down by the main valve spring force, the gap between the main valve flap and the main valve seat is reduced, the medium flow rate is also reduced, and the pressure behind the valve is also reduced. The new balance, on the other hand, when the post-valve pressure is lower than the set pressure, the gap between the main disc and the main valve seat increases, and the medium flow rate also increases, so that the post-valve pressure also increases to reach a new balance.

The operation of the steam pressure reducing valve is controlled by the pressure behind the valve. When the pressure sensor detects that the valve pressure indication is increased, the valve opening degree of the pressure reducing valve is decreased; when the pressure reducing valve is detected, the pressure is decreased, and the opening degree of the pressure reducing valve is increased to meet the control requirement. Steam Pressure Reducing Valve - The pressure reduction ratio of the valve must be somewhat higher than the system value; it should be able to respond to positive or negative control signals even at maximum or minimum flow. These valves should be selected for a useful control range, ie 20% to 80% of the maximum flow. Normally equal or have proportional characteristics. These types of valves inherently have the optimum flow characteristics and flow ranges required for proportional control.

Steam pressure reducing valve Y43H-16, available in 0.05-0.4MPa, Y43H-25, available in 1~1.6MPa, Y43H-40, with 1~1.6MPa, 1.6~2.5MPa adjustment spring, Y43H-64, available 1~3MPa adjustment spring, 0.1~1MPa, spring is installed in the valve at the factory, and the rest is attached with the valve. The user can choose according to the outlet pressure value. The pressure reducing valve usually has various specifications such as DN50 to DN100. The working pressures before and after the valve are <1 MPa and 0.1 to 0.5 MPa, respectively, and the error of the pressure regulating range is ±5% to 10%.

The steam pressure relief valve must be flushed and cleaned prior to installation. In order to prevent the welding slag, oxide scale and other sputum from flowing into the valve, affecting the normal operation of the valve. The steam pressure reducing valve should be installed in a place convenient for operation and maintenance, and must be installed upright on the horizontal pipe. It should be noted that the flow direction of the medium in the pipe is consistent with the direction indicated by the arrow on the valve body, and must not be reversed.

A filter should be installed in front of the steam pressure reducing valve to prevent debris in the medium from entering the pressure reducing valve and affecting its performance. There should be a straight pipe before and after the installed pressure reducing valve. The length of the straight pipe in front of the valve is about 600 mm, and the length of the straight pipe behind the valve is about 1000 mm.

When installing and using the steam pressure reducing valve, the shut-off valve of the bypass pipe should be opened to eliminate the mixture of condensed water and soda water in the pipeline to prevent the garbage valve from being damaged when the pressure reducing valve is opened. When there is no abnormality After the phenomenon, slowly rotate the adjusting screw clockwise to adjust the outlet pressure to the required pressure (according to the valve back pressure). After adjustment, tighten the lock nut and screw the protective cover.