Round Rotary Oil Tank Hatch Cover | CB/T 282 Type A for Oil Tankers

Round Rotary Oil Tank Hatch Cover | CB/T 282 Type A for Oil Tankers

Product Overview

The CB/T 282 Type A rotary oil tank hatch cover is a circular access closure used at cargo-oil-tank passageways on oil tankers. After the securing clips are released, the cover is moved by its rotary or horizontal-swiveling arrangement to clear the round access opening. When closed, the clips compress a cargo-compatible sealing gasket against the seating surface to provide the specified oil-tight closure.

Type A is the round configuration with nominal clear openings from 600 to 1,200 mm; Type B is the oblong configuration. CB/T 282-1994 is a legacy standard that has been replaced by CB/T 4318-2013. The Type A page is therefore most suitable for replacement projects, existing tanker drawings, or orders that specifically retain CB/T 282 dimensions. For newbuilding, the applicable current standard, cargo compatibility, access requirement, coaming structure, test method, and classification scope should be confirmed before production.

Quick Specifications

• Product type: Round rotary oil tank access hatch cover → provides personnel and maintenance access to tanker cargo-oil tanks.
• Standard and configuration: CB/T 282-1994 Type A → circular cover; Type B under the same legacy standard is oblong.
• Clear opening range: 600 / 700 / 800 / 1,000 / 1,200 mm → supports access selection according to vessel drawing and tank-entry requirements.
• Opening method: horizontal rotary / swiveling movement → differs from a conventional vertically hinged hatch and requires clear deck sweep space.
• Sealing principle: multiple clips compress the gasket around the circular seating surface → sealing depends on uniform clip adjustment and gasket condition.
• Reference weight: 295–630 kg → relevant to fabrication handling, installation planning, rotary-support alignment, packing, and freight.
• Material basis: welded marine steel construction → stainless or duplex stainless alternatives require approved drawings and compatible welding procedures.
• Gasket and testing: select by cargo, temperature, and project requirement → oil-tight, watertight, weathertight, and gas-tight claims must not be treated as interchangeable.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm CB/T 282 Type A round configuration, clear opening size, and whether the order is for legacy replacement or a newbuilding project.

Step 2: Provide the vessel deck and tank-access drawing showing deck opening, coaming height, rotary sweep area, nearby piping, handrails, and operating clearance.

Step 3: Confirm construction material and welding requirement: marine steel, stainless steel, duplex stainless steel, or another approved material according to project specification.

Step 4: State cargo type, cargo temperature, gasket material requirement, chemical compatibility, expected cleaning media, and spare-gasket requirement.

Step 5: Confirm closure performance and inspection scope: oil-tightness, watertightness, weathertightness, or gas-tightness; specify the required test method rather than listing all tests as standard.

Step 6: Provide quantity, vessel type, classification society, certificate scope, surface treatment, delivery destination, required delivery time, and reference drawing or photographs.

Structure

Round welded cover | Circular tank-access coaming | Rotary / swiveling support mechanism | Multiple securing clips | Cargo-compatible sealing gasket | Continuous seating surface | Deck welding interface | Operating handle and locking arrangement according to confirmed drawing

Sealing, Operation & Engineering Advantages

• The circular Type A opening provides a continuous sealing perimeter and is readily identified against the oblong Type B configuration during replacement selection.
• Horizontal rotary opening avoids lifting the complete heavy cover into a vertical position, but the deck layout must provide sufficient sweep area and a positive open-position restraint.
• Multiple clips distribute closing force around the gasket. Clip threads, pins, contact faces, and adjustment should be checked so local over-compression does not mask insufficient compression elsewhere.
• The seating surface should be continuous, clean, and free from weld spatter, sharp irregularities, coating build-up, or distortion that could create a leakage path.
• Gasket material must be selected for the actual cargo and temperature. Neoprene, NBR, HNBR, FKM, and PTFE-based solutions have different chemical and compression behaviour and are not universal substitutes.
• The rotary support, cover centre of gravity, clip arrangement, and coaming alignment should allow controlled operation without binding, uncontrolled swing, or impact against nearby deck equipment.
• The coaming and deck connection transfer cover weight, operating force, and local service loads into the ship structure; deck cut-out, welding detail, reinforcement, and distortion control require shipyard confirmation.
• Oil-tightness is the product's primary functional description. Separate gas-tight, watertight, or weathertight ratings require an approved design and a defined test or acceptance criterion.

Custom Attributes

• Legacy Standard: CB/T 282-1994 → suitable for confirmed replacement or vessel-drawing requirements; current-standard review is required for newbuilding.
• Type: A round → circular oil tank access opening; different from the Type B oblong configuration.
• Clear Opening: 600–1,200 mm → select according to tank-entry, inspection, maintenance, and evacuation requirements.
• Opening Direction: Horizontal rotary / swiveling → confirm sweep radius, operating side, open-position restraint, and nearby deck interference.
• Securing Arrangement: Multiple clips → exact quantity, thread, material, and spacing follow the confirmed standard drawing.
• Seal: Cargo-compatible gasket → final compound and section must be confirmed from cargo list, temperature, pressure, and approval requirement.
• Installation: Welded tank-access coaming → coaming height, plate thickness, weld detail, deck reinforcement, and coating repair require project drawings.
• Certificate Requirement: Available according to order scope → type approval, material certificate, maker certificate, and class attendance must be agreed before quotation.

How It Works

Release securing clips → Raise or disengage the cover from the gasket seat as defined by the mechanism → Rotate the round cover horizontally clear of the opening → Complete tank access or inspection → Rotate the cover back into alignment → Tighten clips progressively and evenly → Verify the specified tightness

Applications

Oil tanker cargo-tank access openings | Cargo-tank inspection and cleaning access | Tank maintenance and repair entry | Legacy CB/T 282 replacement projects | Vessel conversions retaining approved round access geometry | Other ship tanks only after service and approval confirmation

Certifications & Advantages

Certificates and inspection can be arranged according to project requirement, approved drawing, material traceability, test scope, and classification society procedure.

Certification: CCS, NK, BV, ABS, DNV, LR, KR, IRS, RS, RINA, CRS, Makers Test Certificate.

Drawing & Photos

FAQ

Q1: Is CB/T 282-1994 still the current standard for rotary oil tank hatch covers?

A1: No. CB/T 282-1994 has been replaced by CB/T 4318-2013. The legacy Type A dimensions remain relevant for repair, replacement, and vessel drawings that specifically call for CB/T 282. Newbuilding projects should confirm the accepted standard with the shipyard and classification society.

Q2: Can one gasket material be used for every oil cargo?

A2: No. Gasket selection depends on the actual cargo, concentration, temperature, cleaning chemicals, expected compression, ageing resistance, and approval basis. The cargo list and service temperature should be provided before the gasket compound is confirmed.

Q3: Does an oil-tight hatch cover automatically qualify as watertight, weathertight, or gas-tight?

A3: No. These terms describe different closure functions and acceptance criteria. The required function, design pressure or exposure condition, test method, and witnessing requirement must be stated in the project specification.