20 Inch four holes tank hatch cover

Specifications 1.Whole diameter: 20"

2.Nominal diameter:10"

3.Emergency open pressure: 21kpa -32kpa

4.Material: Aluminum alloy

 1. Manhole Cover          Manhole Cover is installed on the top of the tanker to prevent the inside fuel from leakage when the tanker is over rolled. With P/V vent inside to adjust the pressure.When there is pressure differences inside and outside the tanker ,it will automatically inlet or exhaust air to adjust the pressure so that it can ensure the safety and environment protection.It is suitable to transpore petroleum ,diesel,kerosene,and the other light fuel,etc.    2. Benefit & Feature   * Emergency Exhausting Design   when the tanker truck is in high temperature condition,the manhole will automatically exhaust the air inside to release the pressure,ensuring the safety of the tanker.   *  With P/V Vent inside   When there is pressure differences inside and outside the tanker,it will automatically inlet or exhaust air to adjust the pressure so that it can ensure the safety and environmental preotection.    * Secondary Open Design   When open the up binder plate ,it will release the pressure out to prevent the workers from pushing over.   * Blinding Holes Design   In the main plate of the Manhole ,there are three blinding holes can be installed with Vapor Vent Valve,Optic Sensor,Dip Tube or Exernal Vacuum Valve according to the user's demand.    * Superior Process Performance    The main plate is stamped ,it is more light and sturdy.    3. Main Size Data   

Name	Model	DO	D1	H	b	z-d
Manholes	C801B-560	Φ 560	Φ 530	88	7	24 - Φ 11
Manholes	C801B-580	Φ 580	Φ 542	88	7	24 - Φ 11

   4. Picture