Technical requirement of fire-fighting ball valve
Surface quality
Fire ball valve surface of anti-corrosion layer or corrosion due process. Coating should be smooth, color should be uniform, peel, scratch etc.
Operating performance
1 fire ball valve should be generally contains the handwheel or handle.
2 the on-off valves should be portable fire, flexible in pressure.all for nominal pressure value, open fire ball valve must not be more than 350 N the force.
3 when fire ball valve is closed, the handwheel or handle generally should rotate clockwise. The handwheel should say. Switch direction The fire ball valve should be one-way seal of the flow direction of medium said.
4 with fire ball in full open position, handle with parallel channels shall generally be spheres.
5 the handwheel or handles shall be installed in the firm, and can be easily disassembled needs or replacement.
6 and seated valves open fire due to the limit.
7 when using pneumatic, electric power or hydraulic drive fire ball valve, the driving device and connection of valve size should conform to the provisions 12223 GB.
Materials
1. the body and bonnet adopts cast-iron or other materials. Iron castings should comply with the GB 12226, GB 12227 regulation. Other materials shall conform to the provisions of relevant technical standards.
2. ball using the copper alloy casting or other materials. The copper alloy casting shall conform to the requirements of GB 12225. Other materials, machinery and corrosion resistance should not below this paragraph of the copper alloy casting.
3. stem material corrosion resistance shall not be lower than the body material.
4. seat, sealing usable ptfe or nylon material such as manufacturing, the seat material of corrosion resistance shall not be lower than the body material.
5. O rubber seal shall conform to the provisions 3452.1 GB.
6. Packing and gaskets and can be used in fire control valves for temperature range. Any metallic gaskets should at least equivalent to the body of corrosion resistance.
7. The handwheel, handles, handle application block, malleable iron or steel ductile iron.
8. The body bleed screw material corrosion resistance shall not be lower than the body material.
These pressure resistance properties
1 shell compression performance
According to the regulations on fire control valves shall, in the test pressure test shell duration, confined and body and bonnet coupling place is not visible, shell leakage (including the stuffing box and body and bonnet coupling place) should not be structural damage. Pressure test pressure in shell leakage, but allow filler sealing experiment to test pressure when should see no pressure.
2 the sealing performance
According to the regulations on fire control valves shall be sealed test in duration should see no leakage.
3 test pressure and test duration
4 Fire ball pressure test, seal test shell, the test pressure and test duration should conform to the provisions of the table
| test item | test pressure | test time，min |
| shell compression pressure test | 1.5 times of nominal pressure value | 2 |
| seal test | 1.1 times of nominal pressure value | 1 |
Static pressure life
According to the regulations on fire control valves should be static life test, test results shall conform to the provisions of the table.
| nominal diameter | frequency |
| ≤100 mm | ≥10000 |
| ≥125 mm | ≥6000 |
The fire ball coating color appearance GB 3181 stipulated by RO3 red.
