Butterfly Technology Agreement
1． Basic parameters: Table 1
table 1
| nominal pressure kPa | nominal diameter mm | connecting screw hole centre distance diameter mm | connecting bolt specifications | |
| recommended dimension | transit dimension | |||
| 150 | 50 | 110 | 125 | M12×4 |
| 150 | 80 | 150 | 160 | M20×4 |
| 250 | 100 | 170 | 100 | M16×8 |
| 250 | 125 | 200 | 210 | M16×8 |
| 250 | 150 | 225 | 240 | M20×8 |
| 250 | 200 | 205 | M20×8 | |
2． Valve body and sealing ring contacting surface should be smooth and flat, and not allowed crack, porosity, porosity and insufficient casting and other defects.
3． Butterfly valve in and out two sealing face should be parallel with each other, the relative bolt holes coaxial degree of connecting flanges at both ends should not exceed 1/2 of the screw hole gap, the connection flange bolt position degree should not exceed 1/4 of bolt and bolt hole.
4． The sealing transmission between the stem and body should be reliable, the stem performance should be flexible and non-catching phenomenon. Maximum rotational torque should be consistent with the Table 2 requirements. Butterfly valve should have the limit measures to ensure the closure tightly.
table 2
| nominal diameter mm | 50 | 80 | 100 | 125 | 150 | 200 |
| maximum rotational torque N·m | 25 | 40 | 50 | 90 | 130 | 150 |
5． When disc in the closed position, the sealing gasket compression should be uniform.
6． Butterfly valve should be able to withstand the pressure of 0.5Mpa, time 30s, the adding pressure of both sides is no leakage.
7． For the vacuum butterfly valve should be able to withstand strength test, 10min leak rate should be less than 1.33pa.1 / s
8． The whole butterfly valve should bear 120 ℃ transformer oil, 168h high-temperature aging test, after tests it is continuing to meet the requirements of sealing performance.
9． Butterfly valve should bear 1000 times of the mechanical rotation test, after test, it still meets the sealing performance requirements
10． Butterfly valve should be clearly marked open and closed.
11． Butterfly valve should be marked with signs in clear position, on which notes
a． product name
b．mode
c．trademark
d．manufacture name
e．date
12． When butterfly valve leaving factory should be accompanied by certification
13． When packaging, the butterfly valve should be closed, the package should be moisture-proof, anti-corrosion, and indicates the product name.
