Butterfly Valve manufacturing company
KNOWLEDGE
 Home >

KNOWLEDGE

> 8 Necessary Technical Factors that Need to Be Considered When Purchasing Valves 2

8 Necessary Technical Factors that Need to Be Considered When Purchasing Valves 2

  • 2021-06-01 19:02

2. Valve material
 

    2.1 The material of the valve body should be mainly ductile iron, and the grade and actual physical and chemical test data of the cast iron should be indicated.

    2.2 Stem material, strive for stainless steel stem (2CR13), large diameter valves should also be stainless steel embedded stems.

    2.3 The nut material is made of cast aluminum brass or cast aluminum bronze, and the hardness and strength are greater than the valve stem.

    2.4 The material of the valve stem bushing shall have a hardness and strength not greater than that of the valve stem, and it shall not form electrochemical corrosion with the valve stem and valve body under the condition of water immersion.

    2.5 Material of sealing surface

    2.5.1 The valve types are different, and the sealing method and material requirements are different;

    2.5.2 For ordinary wedge gate valves, the material, fixing method and grinding method of the copper ring shall be explained;

    2.5.3 Physical, chemical and hygienic testing data of soft sealing gate valve and valve plate lining material;

    2.5.4 The butterfly valve should be marked with the sealing surface material on the valve body and the sealing surface material on the butterfly plate; their physical and chemical test data, especially the hygienic requirements of rubber, anti-aging performance, and wear resistance; usually nitrile rubber and ternary Ethylene-propylene rubber, etc., mixed with reclaimed rubber is strictly prohibited.

    2.6 Valve shaft packing

    2.6.1 Since the valves in the pipe network are usually opened and closed infrequently, the packing is required to be inactive for several years, and the packing does not age, so as to maintain the sealing effect for a long time;

    2.6.2 The valve shaft packing should also have a good sealing effect when it is subjected to frequent opening and closing;

    2.6.3 In view of the above requirements, the valve shaft packing shall not be replaced for life or for more than ten years;

    2.6.4 If the packing needs to be replaced, the valve design should consider measures that can be replaced under water pressure. 

Continued on the next page 


 

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

IPv6 network supported

IPv6 network supported Google Anylitics Console

contact

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