ZHEJIANG ZHENGFENG VALVE Flange triple offset butterfly valve, which is triple offset design, can withstand up to 900 LB level, temperature as low as -196 ℃, up to 700 ℃, sealed to zero leakage, control ratio up to 100: 1 or more. In other words, in a variety of harsh, critical process control pipeline, whether it is switch valve or control valve, the three eccentric butterfly valves will be your best choice, which is safe and low cost.
The valve main materials include 304, 304L, 316, 316L, A105, WCB,Hastelloy , Inconel, LC2, LC3,LCB, WC6, WC9, C5, 4A, 5A, Monel, nickel alloy, titanium alloy, 20 alloy steel etc.
|Connection Type||Flange ends|
|Operation||Manual gear box|
|Cv figure in Full Open Position||3780|
|Face to face length||178mm|
|Painting Color RAL number||RAL9005|
|Suitable Temperature||-29°C ~ 280°C|
|Valve Structure||Triple offset|
|Suitable service||Water , Oil and gas|
【SEAT OVERLAY TECHNICS COMPARITION】:
The procedure of surfacing the sealing surface of ZFVALVES seat is as follows:
1. The wire number is Stellite 6.
2. Welding wire shall be filament (diameter 3.2 mm or 4.0 mm)
3. Argon Arc Welding (TIG)
4. Surfacing thickness not less than 4.5 mm
5. Preheating temperature 150-200 degrees Celsius
6. The interlayer temperature is about 500 degrees Celsius, the number of surfacing layers is 2, the post-weld heat treatment temperature is 700 degrees Celsius, and the heat preservation time is 3 hours.
7. Surfacing width according to design drawings
8. No porous impurities or cracks are allowed in the surfacing layer.
9. Hardness of weld layer HRC38-42
*Attention: Surface roughness of valve seat before surfacing is above Ra12.5 micron. Surface contamination such as rust, grease and water should be strictly cleared. No cracks, spalling and other defects should be allowed.