Marine Hydraulic Sliding Watertight Door | Below-Waterline Bulkhead Closure

Marine Hydraulic Sliding Watertight Door | Below-Waterline Bulkhead Closure

Product Overview

The marine hydraulic sliding watertight door is a horizontally moving steel bulkhead door intended for internal watertight subdivision boundaries below the relevant watertight deck or waterline, subject to the vessel’s approved arrangement. Typical locations include connections between the engine room and steering gear room, boiler room, shaft tunnel, or other machinery spaces where a swing door would occupy valuable passage space.

Hydraulic power provides routine opening and closing, while local manual operation from both sides and a remote manual operating position above deck can be arranged according to the approved control scheme. Selection must be based on clear doorway size, bulkhead opening, overall installation envelope, opening direction, design water head, control and alarm requirements, coating system, and classification scope. The supplied dimensional series is referenced to GB 10840-1989; the contract standard should be reconfirmed because the current Chinese standard catalogue lists CB/T 3007-2011 for this product type.

Quick Specifications

• Product type: Horizontally sliding, hydraulic power-operated watertight bulkhead door → avoids a swing radius and supports passage closure in machinery-space subdivision bulkheads.
• Supplied clear opening range: 600 × 1200 to 1200 × 2000 mm → six doorway options for vessel layout, newbuilding, or replacement matching.
• Standard basis: GB 10840-1989 dimensional reference → the contract should confirm whether CB/T 3007-2011 or another class-approved standard governs the project.
• Material: Mild steel door and frame → exact steel grade, material traceability, and welding procedure remain to be confirmed.
• Operating arrangement: Hydraulic actuation with local manual controls on both sides and upper-deck hand operation as specified → provides an alternative means of operation when the power system is unavailable.
• Opening direction: Left-hand or right-hand → the viewing side and direction reference must be stated on the approved GA drawing.
• Testing: Hydraulic system functional / pressure test plus watertightness pressure, hose, or equivalent leak test as applicable → test head and witness scope depend on location and class requirements.
• Class and control package: Certificate, remote closing, position indication, alarm, interlock, and emergency power arrangements are subject to project requirement and approval.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm the governing standard and statutory category: vessel type, door location relative to the bulkhead / freeboard deck, damage waterline, and frequency of use at sea.

Step 2: Select the clear doorway B × L, then verify the required bulkhead opening B1 × L1, overall installation envelope B2 × L2, and left- or right-hand opening direction.

Step 3: Provide the approved watertight bulkhead drawing, design water head, surrounding reinforcement, frame seating surface, and available maintenance / operating space.

Step 4: Confirm the hydraulic system scope: centralized or independent power pack, working pressure, local and remote controls, manual operating arrangement above deck, alarm / indication, and required opening / closing time.

Step 5: Confirm steel grade, sealing arrangement, coating system, any fire-rating requirement, hydraulic and watertightness test scope, class society, witness inspection, and certificate type.

Step 6: Provide quantity, vessel type, installation position, delivery destination, required delivery time, and existing door photographs or replacement dimensions when applicable.

Structure

Steel door leaf | Welded bulkhead frame | Horizontal guide and support arrangement | Hydraulic actuator and piping interface | Local operating controls on both sides | Manual / emergency operating mechanism | Sealing and seating surfaces | Left- or right-hand opening configuration

Hydraulic, Installation & Watertight Integrity Advantages

• Horizontal sliding motion avoids the swing envelope of a hinged door and is suitable for confined machinery-space passages where adjacent equipment limits clearance.
• The supplied dimension set separates the clear doorway, structural bulkhead opening, and overall equipment envelope, allowing the shipyard to check access, steelwork, and installation space before production.
• Local manual operation on both sides and an upper-deck manual operating arrangement can be incorporated according to the approved scheme, providing a non-power operating route when required.
• Watertight performance depends on door-leaf and frame strength, controlled seating and seal compression, guide alignment, and the approved design water head rather than the door size alone.
• The bulkhead cut-out, surrounding reinforcement, frame flatness, and welding sequence should be verified by the shipyard or design office to prevent distortion that could affect sliding travel or sealing.
• Hydraulic piping, controls, indication circuits, and alarm interfaces should be arranged close to the bulkhead and protected according to the vessel’s damage, fire, and machinery-space design requirements.
• Factory functional testing, hydraulic system pressure testing, watertight pressure testing, and shipboard hose or equivalent leak testing can be arranged according to the agreed inspection plan.

Custom Attributes

• Standard Basis: GB 10840-1989 supplied reference → current project standard and drawing approval should be confirmed before quotation.
• Door Motion: Horizontal sliding → no hinged-door swing radius is required in the passage.
• Clear Opening: 600 × 1200 to 1200 × 2000 mm in the supplied series → custom dimensions require engineering review and an approved drawing.
• Opening Direction: Left-hand or right-hand → specify the viewing side and arrow direction on the GA drawing.
• Primary Material: Mild steel → exact plate grade, traceability, welding consumables, and corrosion allowance are to be confirmed.
• Operating Mode: Hydraulic power with manual operation provisions → power pack, accumulator, piping, local control, and remote control scope are project-specific.
• Watertight Design Head: To be confirmed → the required pressure basis depends on the door’s position and the approved damage-stability arrangement.
• Control & Alarm Package: To be confirmed → bridge indication, remote closing, audible / visual alarm, interlock, and emergency power requirements depend on vessel rules.
• Testing & Certificate: According to project requirement → test head, leakage acceptance, class witnessing, and certificate type must be agreed before manufacture.

How It Works

Hydraulic pressure drives the actuator → The door leaf travels horizontally along the guide arrangement → The leaf reaches the closed seating position and the sealing surfaces establish the watertight boundary → Local manual controls and the specified remote manual mechanism provide an alternative operating route → Door position, alarm, and remote-close functions operate according to the approved control scheme

Applications

Engine room–steering gear room passage | Main and auxiliary machinery spaces | Boiler or machinery compartments | Shaft tunnel access | Internal watertight subdivision bulkheads | Newbuilding and replacement projects

Certifications & Advantages

Class inspection and certification can be arranged according to the project specification, approved drawing, material traceability, test scope, and survey requirements. The requested society and certificate type must be agreed before quotation and remain subject to class approval.

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

Drawing & Photos

FAQ

Q1: Which dimensions must be checked before ordering a replacement sliding watertight door?

A1: Confirm the clear doorway B × L, bulkhead opening B1 × L1, overall envelope B2 × L2, opening direction, sill and track arrangement, surrounding reinforcement, and available actuator / maintenance space. An existing GA drawing or site measurement record should be provided.

Q2: Can the door still be operated if hydraulic power is unavailable?

A2: The supplied description calls for manual operation from both sides and a manual operating position above deck. The exact hand gear, hand pump, valve arrangement, operating time, and approved emergency procedure must be confirmed in the project drawing and class scope.

Q3: What tests and certificates should be specified?

A3: Confirm the hydraulic system functional and pressure test, watertightness pressure test based on the approved design head, shipboard hose test or accepted equivalent, operation test, class witnessing, material certificates, and final product certificate. These items are not assumed to be included unless stated in the quotation.

Zhongyuan Ship Machinery Manufacture (Group) Co., Ltd. was founded in the 1990s and has developed into an integrated marine equipment manufacturer and project supply partner combining manufacturing, technical support, and export services. The group consists of four factories and one export trading company, with more than 300 employees, including over 20 experienced technicians and engineers. Our export company supports global customers with project communication, technical documentation, logistics coordination, and after-sales service.

Our factories are certified to ISO 9001, ISO 14001, ISO 45001, and related occupational health and safety management standards. We also hold type approval certificates from major classification societies such as DNV, LR, BV, and ABS, as well as works approval certificates, class-approved WPS procedures, and qualified welders. Our products can be supplied with certificates from IACS classification societies including DNV, ABS, LR, BV, CCS, RINA, KR, NK, IRS, and RMRS, depending on project requirements.

We manufacture a wide range of marine and offshore equipment, including deck equipment and machinery, mooring and towing equipment, deck outfitting, shafting components, rudder stocks, shaft and rudder systems.

In addition to our manufactured products, we also supply selected marine equipment through qualified partner manufacturers, including hydraulic cylinders, hydraulic power units, marine hardware, lifting and lashing equipment, hoisting and rigging products, lifeboats, rescue boats, launching appliances and davits, life-saving equipment, fire-fighting equipment, rubber fenders, rubber packing, marine pumps, valves, pipe fittings, multi-core pipes and accessories, steel wire ropes, mooring ropes, rope nets, anchors, anchor chains, and various marine chains.

Our main production facilities include CNC machining centers, CNC machine tools, CNC cutting machines, boring and milling machines, hydraulic presses, plate rolling machines, welding robots, welding equipment, shot blasting equipment, and dust-free painting workshops. These facilities enable us to support customized manufacturing and project-based production for shipbuilding, ship repair, offshore, and marine engineering projects.

We are committed to providing reliable, high-quality, and cost-effective marine equipment to customers worldwide. With our manufacturing capability, technical support, qualified supply network, and export coordination experience, Zhongyuan aims to be a trusted partner for shipyards, shipowners, offshore companies, and marine equipment distributors.