Two-Position Three-Way Valve – Smooth Flow Direction Switching

Two-position three-way valve is a hydraulically driven diaphragm control valve with low-pressure sealing and smooth flow direction switching. It can be combined with sand filter or disc filter / screen filter to form an automatic backwash filtration system. It can also be used in water supply systems to change the flow direction of water.

Features

The control valve has two control chambers. By changing the assembly direction of the spring, it can be transformed into two types of valves: angle flow direction and straight flow direction. The unique cavity design enables it to handle extremely large water flow.
Hydraulic driven diaphragm control valve
Unique plastic valve core component design, strong sealing, strong corrosion resistance
Short valve stroke, smooth and stable flow direction change, avoiding the mixing of clean water and sewage
PP material valve body design, corrosion-resistant, acid and alkali resistant, long service life
The drive unit can be independently disassembled, allowing for convenient online inspection and maintenance.

Working Principle

The water to be treated enters the two-position three-way valve through the inlet pipe, and under valve control, the water flow enters each unit for filtration.

The filtered water flows from the internal channel of the filtration unit into the outlet. As filtration progresses, the impurities adsorbed by the filter increase. When the pressure difference reaches the set value or the set time, the system enters the backwash mode. The controller first sends a signal to the three-way valve corresponding to the first filter unit, which will change the direction of the water flow, close the inlet, and open the drain outlet. Under pressure, the backwash water flows through the outlet pipe into the filter for washing, and the sewage is discharged from the drain outlet.

After washing, the unit returns to the filtration mode, and the system performs backwash on the next unit until all units are washed and the system returns to the filtration mode.

Diagram of the working principle of 4 two-position three-way valves

Specifications

4 different models of two-position three-way valves

Two-position three-way valve models

The dimensional diagram of 2 two-position three-way valves

PWV-1, PWV-2 & PWV-3 model dimension diagrams

PWV-4 Model Dimension Diagram

Table 1: Two-Position Three-Way Valve Dimensions
Product Model	D (mm)	W (mm)	H (mm)
PWV-1	274	180	160
PWV-2	378	287	192
PWV-3	464	277	260
PWV-4	316	187	170

Table 2: Two-Position Three-Way Valve Technical Parameters
Product Model	Specifications	Connection Method	Maximum Flow Rate (m³/h)	Working Pressure (bar)	Weight (kg)
PWV-1	2" x 2" x 2"	BSP / NPT / VIC	30	0.7–10	2.8
PWV-2	3" x 3" x 3"	VIC	50	0.7–10	5.5
PWV-3	4" x 4" x 4" (3")	VIC	100	0.7–10	9.9
PWV-4	4" x 4" x 3" (4")	VIC	80	0.7–10	5.5