Pneumatic Eccentric Hemisphere Valve
The executive system is pneumatic driven. A single cylinder or double cylinders are available according to the size of valve diameter. The advantages of semi-spherical valves have been fully developed to fulfill automation or semi-automation of valve operation. They are divided into 4 types: QBQ641W, QBQ641H, QBQ641M, and QBQ641M1, and have the following advantages:
1.Straight through. It is made for single direction sealing and an eccentric structure. The ball is divorced from the valve body when opening, therefore assuring a straight passage and making it impossible for the flow to be jammed.
2.Easy open and close. There is no contact between the valve core and the valve seat when opening, therefore causing little torque and free turning. While the function of squeezing and cutting between the semi-sphere and seat removes the fouling adhesives on the sealing surfaces when closing, therefore assuring a tight and reliable sealing.
3.The eccentric structure of the sealing surface enables an automatic repairing of the spherical wearing. This results in a good sealing, long working life, and safety and reliability.
4.The valve is a kind of hard sealing structure. Different anti-abrasive alloys are chosen for different medium. At the same time the hardness and anticorrosion are also guaranteed.Main Specifications
Nominal Pressure | 0.6 | 1.0 | 1.6 | 2.0 | 2.5 | 4.0 | 5.0 | 6.4 | 10 | |
Shell Test Pressure | 0.9 | 1.5 | 2.4 | 3.0 | 3.8 | 6.0 | 7.5 | 9.6 | 15 | |
High Pressure Sealing Test | 0.66 | 1.1 | 1.76 | 2.2 | 2.75 | 4.4 | 5.5 | 7.04 | 11 | |
Applicable Medium & Temperature | QBQ641W | water, vapor, pulp and other solutions. t≤425℃ | ||||||||
QBQ641H | Natural gas, coal gas, liquefied gas crude oil, heavy oil. t≤425℃ | |||||||||
QBQ641M | Conveying of solutions and ore slurry. t≤425℃ | |||||||||
QBQ641M1 | Alumina powder, coal powder, coal ash, dusty gas, waste residues, etc. t≤350℃ | |||||||||
Note: The pressure of air sealing test is 0.6 MPa in all cases.
Materials and Codes of Main Parts
Name of parts | QBQ641W | QBQ641H | QBQ641M | QBQ641M1 |
Valve body | Carbon steel | Carbon steel, WCB, Stainless steel | Carbon steel | Carbon steel, WCB |
Stem | 45# | 45#2Cr13 | 45#40Cr | 45# |
Sealing set of disc | Nitriding steel | Special hard alloy steel Cr-Mn-Si | Special hard alloy steel Cr-Mo-V | Special hard alloy steel Cr-Mo-V |
Sealing set of seat | W | Special hard alloy steel Cr-Mn-Si | Special hard alloy steel Cr-Mo-V | Special hard alloy steel Cr-Mo-V |
Note:
1. The product adopts convex flanged, flanging sizes in accordance with GB/T 9113. 1- 2000.
2. Refer to GB 12221-89 for structure lengths.
3. Refer to GB-122237-89 for technical specification of manufacturing and acceptance.
4. JB/T 9092-1999 and GB/T13927-92 are followed for pressure test.
