Analysis of Working Principle and Structural Features of Six Way Directional Valve

In the petroleum, chemical, mining and metallurgical industries, six-way valve is an important fluid reversing equipment. The valve is installed in the pipeline of the lubricating oil delivery system. By changing the relative position of the seal assembly in the valve body, each channel of the valve body can be communicated or disconnected to control the commutation and start-stop of the fluid. Six-way valve performance parameters Nominal diameter (mm) 50 ~ 150 Applicable temperature (℃) Room temperature ~ 80 Nominal pressure (MPa) 1.0 Applicable media Lubricating oil Connection flange strength test pressure (MPa) 1.5 Seal test pressure MPa) 1.1 Pressure test temperature (℃) Working principle and structural characteristics of the six-way reversing valve at room temperature Six-way reversing valve is mainly composed of the valve body, seal assembly, cam, stem, handle and bonnet and other components 1). The valve is driven by the handle, which drives the valve rod and the cam to rotate through the handle. The cam has the functions of locating and driving the sealing and opening and closing of the sealing component. The handle rotates counterclockwise, two sets of sealing components respectively close the two lower channels under the action of the cam, and the two upper channels communicate with the inlet of the pipeline device respectively. On the contrary, the upper two channels closed, the lower two channels and pipeline devices connected to the import, to achieve a non-stop commutation. Figure 1 6-way reversing valve 1 Upper bonnet 2 Handle 3 Valve stem 4 Cam 5 Seal assembly 6 Bonnet 7 Valve body (1) The valve body of the 6-way valve is divided into two chambers by a partition, each chamber has 3 passages , The middle of the inlet, both ends of the outlet. Body for the carbon steel welding structure, small size, light weight, compact structure, improve the utilization of materials, shorten the production cycle and reduce costs. Welding surface sealing stainless steel, corrosion-resistant rust-proof, sealing surface after finishing polished grinding, surface roughness Ra ≤ 0.8μm. (2) six-way valve has two sets of seal components. Each seal assembly (Figure 2) consists of a flap, seal, adjustment block, adjusting screw, cleat and bolt. Valve for the carbon steel welding pieces, with ribs, that is, increasing the strength of the valve and guide, to ensure that each valve between the concentricity. Valves embedded in polyurethane rubber ring, the material has oil, abrasion resistance, stable performance, good sealing and long service life. Under the action of the cam, the spherical surface of the sealing ring comes into contact with the sealing surface of the valve body to generate squeeze elastic deformation and achieve the sealing effect. Adjusting block and adjusting screw can adjust the two sealing components when they can not synchronize in place to ensure the sealing performance of each channel synchronizes in place. Figure 2 Seal assembly 1 Clamp 2 Bolt 3 Adjustment block 4 Clapper 5 Sealing ring 6 Adjusting screw (3) O-ring is used for the axial seal between stem and body bulkhead and upper bonnet. (4) The baffle body and the upper bonnet shaft hole are inlaid with copper sleeves, which can reduce the friction moment with the O-ring, the sealing assembly is opened and closed flexibly, and the operation moment is small. (5) on the bonnet is provided with signs and limit screws, the valve stem to install the pointer, a clear indication of the access of each channel, easy to operate.