Tank Manhole Covers

Our professional-designed tank truck manhole covers, built-in vent valves, and flange connection assemblies ensure safe, efficient, and leak-free operations, suitable for petroleum, chemical, and hazardous liquid transportation.

Manhole Covers: Carbon Steel & Cast Aluminum

Carbon Steel Manhole Covers (RKG Series)

Equipped with vacuum pressure vent valves and spring-loaded emergency relief valves to automatically balance tank pressure.

Protects the tank from overpressure, negative pressure, and emergency situations.

Materials: Handle, cover plate, and neck ring made of galvanized carbon steel; emergency relief valve made of aluminum alloy; sealing ring options: Buna-N or Viton.

Pressure range: Vent 6–12 kPa, negative pressure -2 to -4 kPa, emergency exhaust 21–32 kPa.

Temperature range: -20°C to +50°C.

Cast Aluminum Manhole Covers (RKG Series)

Lightweight, corrosion-resistant, aluminum plates with oxidation treatment.

Can be equipped with dual vent valves, optical sensors, dip tubes, or external vacuum valves according to requirements.

Materials: Cast aluminum cover plate, galvanized steel handle, aluminum alloy emergency relief valve; sealing rings: Buna-N or Viton.

Compact size reduces manufacturing cost while ensuring reliable safety performance.

Both types comply with NTTC DOT406, GB18564.1, EN, and ADR standards, ensuring global operational reliability for tank trucks.

Built-in Vent Valves (HBPV-BI & ALPV-BI Series)

HBPV-BI Series

Installed on the inner side of the manhole cover.

Automatically balances pressure differences between the tank interior and exterior.

Anti-spill flow design activates during unexpected tank tipping, effectively preventing fuel leakage.

Customizable pressure: Positive 6–12 kPa, negative -2 to -4 kPa.

ALPV-BI Series

Lightweight design, suitable for cast aluminum manhole covers.

Pressure range: Positive 6–8 kPa, negative -2 to -3 kPa.

Structure includes vent valve body, valve disc, valve stem, anti-spill cap, and spring for reliable operation.

These vent valves ensure tank breathing efficiency, timely pressure release, and emergency protection, compatible with both carbon steel and cast aluminum manhole covers.

Flange Connection Assemblies

RKG-S Series Carbon Steel Welding Flanges

High-strength bolted connection ensures secure installation and leak-proof operation.

Available diameters: 460 mm, 560 mm, 580 mm, with matching bolt hole specifications.

RKG-G Series Oil-resistant Cork Rubber Gaskets

Paired with RKG-S flanges to provide excellent sealing and oil/chemical resistance.

Ensures safe operation during loading, unloading, and transportation.

Applications

Rapid loading and unloading systems for tank trucks

Petroleum and chemical liquid transportation

Fuel depots and storage terminals

Hazardous liquid transport operations

Our manhole covers, vent valves, and flange assemblies provide high operational safety, environmental protection, and international standard compliance.

Why Choose Zhejiang Haibo Petroleum Equipment Co., Ltd.?

Professional manufacturer of tank truck manhole covers, built-in vent valves, and flange connection assemblies.

Materials: Carbon steel, cast aluminum, galvanized steel, oil-resistant gaskets.

Customizable according to client requirements: pressure settings, flange dimensions, auxiliary devices.

Compliant with NTTC DOT406, GB18564.1, EN, ADR international standards.

Durable, reliable, and easy to maintain.