1. The main body of the light manhole cover is made of light aluminum alloy, which is formed by low-pressure die-casting. It is light and strong, and can effectively improve the bearing capacity of the oil tanker under the premise of ensuring the forward degree

2. Corrosion resistant die casting aluminum alloy material has good corrosion resistance and wear resistance after special treatment

3. The built-in breathing valve is equipped with breathing valve under the small manhole cover, which can set different pressure according to needs to ensure reliable breathing function, making the tank car safe and reliable and not easy to damage in the transportation process

4. Emergency exhaust device when the tank car has an accident or the container is in fire, the pressure inside the tank needs to be released at high temperature to prevent explosion.The device can automatically exhaust emergency, when the pressure in the tank reaches 21-35kpa, emergency exhaust pneumatic work, its maximum displacement of 7000m cubed /h above

5. Automatic dumping sealing device in case of accident, when the tank truck is dumped, the dumping anti-overflow valve in the breathing valve ACTS to automatically seal the channel to prevent the risk of leakage of transportation medium

6. There are three auxiliary openings on the cover of the large manhole with three spare openings, which can be used to install oil and gas recovery valve, pipette, anti-overflow probe rod or as oil gauge hole

Ductile Cast Iron Heavy Duty galvanized steel Manhole Covers