Manhole cover is an oil tank truck part mounted on the top of tanker for refilling oil, oil and gas recovery inspection and maintenance of tanks. In the event of an emergency, the manhole cover protects the tank. This is a special cover with built-in breathing and emergency venting functions, and can be fitted with oil and gas recovery valves, oil measuring holes, and overflow prevention probe rods on the manhole cover. During the filling process, when the liquid level reaches the detection position, the overflow prevention sensing system will automatically alarm and stop filling.
Under normal conditions, the manhole cover breather valve is closed, but filling the tank with oil, releasing the oil and changes in outside temperature can cause pressure changes inside the tank (e.g. atmospheric pressure and vacuum pressure). The breather valve of the manhole cover will automatically open under a certain atmospheric pressure and vacuum pressure to keep the internal pressure of the tank stable during oil transportation. Its overflow prevention design keeps the tanker sealed in the event of an accident, and the emergency venting device will automatically open to release the pressure inside the tank in the event of a sharp rise in tank pressure, thus preventing accidents and greatly improving the safety of oil transportation.
Features:
- Manhole cover emergency exhaust valves are equipped with a breather valve.
- The breather valve ventilates the tank in accordance with the regulations, and different pressure settings apply to different operational requirements.
- Emergency venting valves have an automatic sealing function to prevent danger and eliminate unnecessary oil spillage.
- A double opening safety device allows the remaining gas in the tank to be safely vented before the cover is fully opened.
- A reserved blind hole in the main cover plate is for the installation of an oil measuring hole or an anti-spill optical probe.
- Produced in accordance with EN 13317:2002.
Technical Parameters
Specification |
16” & 20” to choose |
Emergency exhaust valve |
10” |
Anti-pressure |
0.254㎫ |
Emergency opening pressure |
21㎪ ~ 32㎪ |
Max. Discharge Pressure |
7000m3/h |
Connection method |
Flange form/other |
Working temperature |
-20℃ ~+70℃ |