Butterfly Valve manufacturing company
 Home >


> 8 Necessary Technical Factors that Need to Be Considered When Purchasing Valves 4

8 Necessary Technical Factors that Need to Be Considered When Purchasing Valves 4

  • 2021-05-09 20:23

5. Valve performance testing

    5.1 When a valve is manufactured in batches of a certain specification, an authoritative organization should be entrusted to conduct the following performance tests:

    5.1.1 The opening and closing torque of the valve under working pressure conditions;

    5.1.2 Under working pressure conditions, the number of consecutive openings and closings that can ensure that the valve closes tightly;

    5.1.2 The detection of the flow resistance coefficient of the valve under the condition of water delivery in the pipeline.

    5.2 The valve shall undergo the following inspections before leaving the factory:

    5.2.1 When the valve is open, the valve body should withstand the internal pressure test that is twice the valve working pressure;

    5.2.2 When the valve is closed, both sides bear 1.1 times the valve working pressure value, and there is no leakage; however, the leakage value of the metal-sealed butterfly valve is not greater than the relevant requirements.



  6. The internal and external corrosion protection of the valve


The inside and outside of the valve body (including the variable-speed transmission box) should be shot blasted to remove rust, and spray powdered non-toxic epoxy resin with a thickness of more than 0.3mm. When it is difficult to electrostatically spray non-toxic epoxy resin for extra-large valves, similar non-toxic epoxy paint should be brushed or sprayed.

    6.2 The inside of the valve body and all parts of the valve plate require comprehensive anti-corrosion. On the one hand, it will not corrode when immersed in water, and there will be no electrochemical corrosion between the two metals; on the other hand, the smooth surface reduces the water resistance.

    6.3 The hygienic requirements of the anticorrosive epoxy resin or paint in the valve body shall have a test report from the corresponding authority. The chemical and physical properties should also meet the relevant requirements.

    7. Valve packaging and transportation

    7.1 Lightweight blocking plates shall be installed on both sides of the valve for solid sealing.

    7.2 Valves with medium and small diameters should be bundled with straw ropes and transported in containers.

    7.3 Large-caliber valves also have simple wooden frame solid packaging to avoid damage during transportation.

    8. Factory instructions of the valve

    Valves are equipment, and the following relevant data should be indicated in the factory instructions:

    Valve specifications; model; working pressure; manufacturing standards; valve body material; stem material; sealing material; valve shaft packing material; valve stem sleeve material; internal and external anti-corrosion material; operating direction; revolutions; opening and closing under working pressure Torque; manufacturer name; delivery date; delivery number; weight; the diameter, number of holes, and center hole distance of the connecting flange; indicate the overall length, width, and height control dimensions in a graphic manner; valve flow resistance coefficient; effective Number of opening and closing; relevant data of valve factory inspection and precautions for installation and maintenance, etc. 

Copyright! 2021 Tianjin Jiangrui Fluid Equipement Co.,Ltd.All Rights Reserved. Powered by WILLIAM

IPv6 network supported

IPv6 network supported Google Anylitics Console


Send A Message

Send A Message

    If you are interested in our valves and want to know more details,please leave a message here,we will reply you as soon as we can.

  • supplier
  • contact
  • email