Strainer Valves Manufacturers

Strainer valves, also known as filter, is a device for filtering pretreatment. It is a filter equipment necessary for using hydraulic control valves and precision mechanical products that are easily blocked. It is an indispensable device in the pipeline series for conveying medium. It is usually installed at the inlet end of hydraulic control valve, pressure reducing valve, pressure relief valve, constant water level valve and other equipment to eliminate impurities in the medium, prevent particulate impurities from entering the channel and causing wall plugs, so as to protect the fittings on the equipment pipeline from wear and blockage When cleaning is required, the detachable filter cartridge can be taken out and re installed after treatment. Therefore, the use and maintenance are extremely convenient.Filter valve refers to the valve with the function of filter medium, usually with filter screen, filter element or with magnetic rod (mainly filter metal)

The filter valve net adopts stainless steel double-layer net structure, which is firm and durable. It has the characteristics of advanced structure, small flow resistance and convenient blowdown. It can be used for water, steam, oil, nitric acid, urea, oxidizing media and other media. The mesh number of the filter screen shall be set according to the user’s needs. Generally, the water supply screen is 18-30 mesh, the ventilation screen is 40-100 mesh, and the oil supply screen is 100-480 mesh. The Y-type filter can also be combined with the expansion joint to form a Y-type telescopic filter with adjustable installation length. Filter screen can be made according to user’s requirements.
When the filter works, the water to be filtered enters from the water inlet, flows through the filter screen, and enters the pipeline required by the user through the outlet for process circulation. The particulate impurities in the water are trapped inside the filter screen. In this continuous circulation, more and more particles are intercepted, and the filtration speed is slower and slower. However, the inlet sewage still enters continuously, and the filter hole will become smaller and smaller, thus generating a pressure difference between the inlet and outlet. When the pressure difference reaches the set value, the differential pressure transmitter will send an electric signal to the controller, and the control system will start the drive motor to drive the shaft to rotate through the transmission assembly. At the same time, the sewage outlet will be opened and discharged from the sewage outlet, After the filter screen is cleaned, the pressure difference drops to the minimum value, and the system returns to the initial filtering state, and the system operates normally. The filter is composed of shell, multi-element filter element, backwashing mechanism, differential pressure controller, etc. The diaphragm in the shell divides its internal cavity into upper and lower cavities. The upper cavity is equipped with multiple filter elements, which makes the filtering space full and significantly reduces the volume of the filter. The lower cavity is equipped with a backwash suction cup. During operation, the turbid liquid enters the lower chamber of the filter through the inlet, and enters the inner chamber of the filter element through the baffle hole. Impurities larger than the gap of the filter element are intercepted, and the clean liquid passes through the gap to reach the upper chamber and is finally sent out from the outlet. The filter adopts high-strength wedge-shaped filter screen, and automatically cleans the filter element through pressure difference control and timing control. When the impurities in the filter accumulate on the surface of the filter element, causing the pressure difference between the inlet and outlet to increase to the set value, or when the timer reaches the preset time, the electric control box sends a signal to drive the backwash mechanism. When the inlet of the backwashing suction cup is directly opposite to the inlet of the filter element, the blowdown valve is opened. At this time, the system releases pressure and discharges water. A negative pressure area with a relative pressure lower than the water pressure outside the filter element appears inside the suction cup and the filter element, forcing part of the net circulating water to flow from the outside of the filter element to the inside of the filter element. The foreign particles adsorbed on the inner wall of the filter element flow into the pan with the water and are discharged from the blowdown valve. The specially designed filter screen makes the inside of the filter element produce spraying effect, and any impurities will be washed away from the smooth inner wall. When the pressure difference between the inlet and outlet of the filter returns to normal or the timer setting time ends, the material flow is not interrupted and the backwashing water consumption is small during the whole process, realizing continuous and automatic production. Filters are widely used in metallurgy, chemical industry, petroleum, papermaking, medicine, food, mining, electric power and urban water supply. Such as industrial wastewater, circulating water filtration, emulsion regeneration, waste oil filtration treatment, continuous casting water system, blast furnace water system and high-pressure water descaling system for hot rolling in the metallurgical industry. It is an advanced, efficient and easy to operate automatic filter device.

The water to be treated by the filter enters the machine body from the water inlet, and the impurities in the water are deposited on the stainless steel filter net, resulting in a pressure difference. The pressure difference at the inlet and outlet is monitored by the pressure difference switch. When the pressure difference reaches the set value, the electric controller sends a signal to the hydraulic control valve to drive the motor. After the equipment is installed, the technicians will conduct debugging, set the filtering time and cleaning conversion time. The water to be treated enters the body from the water inlet, and the filter starts to work normally. When the preset cleaning time is reached, the electric controller will send signals to the hydraulic control valve and drive the motor, causing the following actions: the motor will drive the brush to rotate to clean the filter element, and the control valve will open to blow down. The whole cleaning process will only last for tens of seconds, When the cleaning is finished, close the control valve, stop the motor, restore the system to its original state, and start the next filtration process. The shell of the filter is mainly composed of coarse filter screen, fine filter screen, sewage suction pipe, stainless steel brush or stainless steel suction nozzle, sealing ring, anti-corrosion coating, rotating shaft, etc.

A simple filter is formed by separating the container into upper and lower chambers with a filter medium. The suspension is added to the upper chamber and enters the lower chamber through the filter medium under pressure to become filtrate. The solid particles are retained on the surface of the filter medium to form filter residue (or filter cake). During the filtration process, the filter residue layer on the surface of the filter medium is gradually thickened, the resistance of the liquid passing through the filter residue layer is increased, and the filtration speed is decreased. When the filter chamber is full of filter residue or the filtering speed is too low, stop filtering, remove the filter residue, and regenerate the filter medium to complete a filtering cycle.