Cast Steel Y-Type Strainer GL41H

Working Principle 

During operation, raw water enters through the inlet, passes through the filter screen, and flows out to the user pipeline for process circulation. Particle contaminants in the water are trapped inside the screen.

With continuous operation, trapped particles accumulate gradually, slowing down the filtration rate while raw water intake remains uninterrupted, resulting in progressive clogging and rising pressure differential between inlet and outlet.

When the pressure difference reaches the preset value, the differential pressure transmitter sends an electrical signal to the controller. The control system drives the motor to rotate the shaft via transmission components, meanwhile the drain port opens to discharge contaminants. After screen cleaning is completed, the pressure difference drops to the minimum, the system returns to initial filtration status and resumes normal operation.

This filter consists of a housing, multi-element filter cartridges, backwashing mechanism and differential pressure controller. An internal diaphragm divides the chamber into upper and lower cavities. Multiple filter cartridges are installed in the upper cavity to maximize filtration area and greatly reduce overall equipment size; a backwash suction disc is mounted in the lower cavity.

In service, unfiltered fluid flows into the lower chamber, then enters the inner cavity of filter cartridges through diaphragm holes. Impurities larger than the cartridge slot size are retained, while purified fluid passes through to the upper cavity and discharges from the outlet.

This unit adopts high-strength wedge wire screen, with automatic cartridge cleaning controlled by pressure difference and preset timer. When contaminant buildup on cartridge surface causes inlet-outlet pressure differential to reach the set point, or when the preset timer expires, the electric control cabinet activates the backwash mechanism.

When the suction disc aligns perfectly with the cartridge inlet, the drain valve opens and the system depressurizes and drains. A negative pressure zone forms inside the cartridge, forcing clean circulating water to flow from outside into the cartridge interior. Particulate deposits on the inner wall are flushed into the disc assembly and discharged through the drain valve. The specially designed screen creates an internal jet effect to thoroughly remove all debris from the smooth inner surface.

Once pressure differential returns to normal or the backwash cycle ends, the whole process maintains uninterrupted medium flow with minimal backwash water consumption, realizing fully continuous and automatic operation.

Application Fields

Widely applied in metallurgy, chemical, petroleum, paper making, pharmaceutical, food, mining, electric power and municipal water supply industries.

Typical uses include industrial wastewater treatment, circulating water filtration, emulsion regeneration, waste oil purification, continuous casting water system, blast furnace water system and high-pressure descaling system for hot rolling in metallurgical plants.

It is an advanced, high-efficiency and easy-to-operate fully automatic filtration unit.