1.The flange is welded to the pipe and cooled to the ambient temperature before the valve can be installed on the flange. Otherwise, the high temperature generated by welding will affect the performance of the elastic seat.

2.The edge of the welded flange must be machined with a lathe until the surface is smooth to avoid injuring the elastic seat during the valve installation process. The surface of the flange must be completely free from damage and deformation, remove all dirt dust and foreign matter, and avoid liquid leakage of the valve and flange interface.

3. Clean the flange and pipe cavity to completely remove the sputtering produced by welding, peeling scale and other foreign bodies left.

4.When installing pipes between valves, accurate alignment of the center of the water pipe is essential for trouble-free operation. The imprecise center points shown in Figure 1 must be avoided.

5.When installing the valve, set the positioning bolt under the pipeline at the same height to support the function, and adjust the distance between the flange until the valve body is about 6-10 mm apart. Remember that the valve can only be opened from the closed position to the 10° position here.

6. Insert the two bolts into the lower side guide rod of the valve, and then carefully install, so that the flange surface will not damage the elastic seat.

7.Then place the other two bolts into the guide rod above the valve to ensure accurate center positioning between the pipe and the valve.

8. Open the valve three times to check whether the contact between the valve plate and the flange is not smooth.

9. Remove the positioning bolts and place all bolts around the valve body for alternating diagonal tightening until the flange touches the valve body.

10. Provide a support for the valve when installing the actuator to avoid the distortion of the valve neck and reduce friction between the valve and the pipe.

11. Do not step on the valve neck or valve handwheel.

12. Do not reverse the installation of DN350 or larger valves.

13.Do not install the butterfly valve directly on the check valve or pump, which may cause damage when contacting the valve plate.

14.Do not install the valve on the downstream side of the elbow and taper pipe, or calibrate the valve when the flow rate changes. When this happens, it is recommended to install the valve at a distance of about 10 times the nominal diameter of the valve.

15.The installation of the valve needs to take into account which valve plate will be subjected to flow rate and pressure during the delivery of liquid.