Marine Electric Mooring Capstan with Horizontal Motor Drive | Deck-Mounted

Product Specification

Marine Electric Mooring Capstan with Horizontal Motor Drive | Deck-Mounted Warping Capstan

Product Overview

This marine electric mooring capstan is a deck-mounted warping machine used to heave and pay out mooring lines during berthing, unberthing, shifting, and line-handling operations. The capstan uses a vertical warping head driven through a reduction gearbox by a horizontally arranged electric motor. The horizontal drive layout keeps the principal drive components above deck for convenient inspection and maintenance, while the complete unit is secured to a prepared deck foundation by bolts according to the approved installation drawing.

Unlike a drum mooring winch, a capstan does not store the mooring line on a dedicated storage drum. Pull is developed by friction between the line and the rotating warping head while the free end is controlled in accordance with the vessel’s mooring procedure. Correct selection therefore depends not only on rated pull and speed, but also on rope type and diameter, warping-head diameter, line lead, bend radius, control position, foundation strength, electrical supply, and the vessel’s complete towing and mooring arrangement.

Quick Specifications

• Function: mooring / warping → used for heaving and paying out mooring lines; not a rope-storage winch.
• Drive arrangement: horizontal electric motor + reduction gearbox → major drive components can be arranged above deck for inspection and maintenance.
• Product-family rated pull: 5–250 kN stated by the source → final rated pull must be confirmed at the specified warping speed and duty.
• Warping head diameter: 200–700 mm stated by the source → select together with rope diameter, rope manufacturer bend-radius guidance, and ISO 6482 warping-end profile requirements where applicable.
• Warping speed: 9–18 m/min stated by the source → single-speed, two-speed, or variable-frequency configuration should be confirmed for each project.
• Reference rope diameter: 11–46 mm stated by the source → final rope type, construction, MBL / LDBF, D/d requirement, and compatibility with the complete mooring system must be confirmed.
• Control: local or remote → control position should provide safe visibility of the working line and mooring area, with emergency-stop and interlock requirements confirmed by project.
• Installation: bolted to a shipboard foundation → foundation, holding-down bolts, deck reinforcement, cable routing, drainage, and access space are vessel-specific.

Operating Principle & Mooring Use

The mooring line is led around the vertical warping head and the electric motor rotates the head through the reduction gearbox. Friction between the line and the warping surface generates the hauling force, while the line handler controls the free tail in accordance with the vessel’s approved mooring procedure. The number of turns on the head should not be treated as a fixed catalogue value; it depends on rope material, surface condition, line load, warping-head profile, and operating procedure.

The capstan should be considered as one component of the entire mooring system. The line lead from the capstan to rollers, pedestal fairleads, chocks, or ship-side fairleads should be as direct as practicable, with unnecessary direction changes avoided. The mooring line, warping head, fittings, supporting structure, controls, and operating area must remain compatible with the vessel’s towing and mooring arrangement plan.

Main Technical Parameters

Warping Head, Rope & Pull Selection

• Rated pull: confirm the required hauling force under the vessel’s actual mooring arrangement. Do not treat the model pull as the mooring line MBL or Ship Design MBL.
• Warping head diameter: check the head-to-rope diameter ratio against rope manufacturer recommendations to reduce bend loss and premature fatigue.
• Rope material: synthetic fibre, natural fibre, or steel wire rope have different friction, stiffness, bend-radius, wear, and handling characteristics; confirm the actual line before fixing the head profile.
• Rope diameter: verify that the selected 11–46 mm range applies to the actual rope construction and not only to a general product-family reference.
• Line lead: the rope should approach and leave the warping head without excessive fleet angle, rubbing against foundations, or avoidable changes of direction.
• Mooring-system compatibility: capstan pull, rope strength, fairleads, chocks, bollards, deck fittings, and supporting hull structure must be reviewed as one system.
• Working limit marking: the equipment marking and vessel documentation should reflect the approved operational limitation and foundation strength; do not create an unsupported SWL from the catalogue pull value.

Electric Drive, Speed & Control

The horizontal electric motor drives the capstan through a reduction gearbox and coupling arrangement. For shipboard supply, the motor and control system should be selected against the vessel’s voltage, frequency, starting method, required speed, duty cycle, ambient conditions, enclosure protection, and class requirement. ISO 7825 provides general deck-machinery requirements and references IEC 60092 for ship electrical installations and IEC 60529 for enclosure protection.

• Single-speed drive → simple configuration where one warping speed is sufficient.
• Two-speed drive → useful when the project requires a lower controlled speed and a higher line-handling speed; the model table appears to contain 10 and 15 m/min options.
• Variable-frequency drive → can be considered where smoother acceleration, adjustable line speed, and reduced mechanical shock are required; final motor and VFD sizing must be engineered for the duty.
• Local control → normally positioned for direct observation of the capstan, line lead, and working area.
• Remote control → available according to project requirement, but control location, communication, emergency stop, restart prevention, and visibility of personnel / line condition must be addressed.
• Electrical data to confirm → voltage, frequency, phase, motor rating, duty, starting current, IP grade, insulation class, space heater, brake arrangement if fitted, control voltage, cable entry, and hazardous-area requirement.

Deck Foundation & Installation

The capstan is bolted to a prepared foundation rather than treated as a free-standing deck appliance. Pull at the warping head produces torque and horizontal reaction that must be transferred through the base, holding-down bolts, foundation, welds, and local deck structure. The vessel designer or class-approved foundation drawing should therefore be completed before final manufacture.

• Confirm capstan centreline, warping-head height, rope lead direction, operating envelope, access to the motor and gearbox, and removal space for maintenance.
• Foundation top plate and mounting face should be sufficiently flat to avoid frame distortion and gearbox misalignment during bolt tightening.
• Holding-down bolt size, grade, quantity, preload, and arrangement must be calculated from the approved equipment reactions and foundation design.
• Provide local deck reinforcement and weld details according to the vessel structure; the equipment rating alone does not establish the strength of the ship’s foundation.
• Arrange cable entries, junction boxes, drainage, lubrication points, gearbox oil access, and inspection covers so routine maintenance does not require unnecessary dismantling.
• After installation, verify alignment, bolt tightening, free rotation, control direction, emergency stop, no-load running, operating speed, and project-specific load / function tests.

Structure

Vertical warping head | Horizontal electric motor | Reduction gearbox | Flexible / flange coupling as applicable | Bearing and shaft assembly | Fabricated or cast support frame | Bolted deck foundation | Local / remote control equipment

Design & Maintenance Advantages

• Horizontal motor arrangement can keep the motor and gearbox above deck, providing direct access for inspection, oil service, coupling work, and motor replacement where deck space permits.
• Vertical warping head accepts a changing rope lead around the head without requiring a storage drum, making the capstan suitable for line-handling stations with limited longitudinal deck space.
• Bolted foundation connection allows the equipment to be removed for overhaul when the vessel foundation and access route are designed accordingly.
• Warping-head diameter can be selected to suit the intended rope size and bend-radius requirement rather than using one head diameter for the entire product family.
• Local or remote control can be configured to suit the mooring station, but safe visibility, communication, snap-back exposure, and personnel position should drive the final control arrangement.
• Maintainable items should include gearbox lubricant, bearings, coupling, warping-head surface, fasteners, seals, electrical enclosure, motor, switches, control station, and foundation bolts.

Inspection, Testing & Maintenance

• Factory inspection → verify material certificates, weld quality, machining, gear contact, shaft alignment, warping-head dimensions, fasteners, coating, and electrical assembly.
• No-load test → confirm rotation direction, abnormal noise / vibration, lubrication, control functions, emergency stop, and speed.
• Load / pull test → perform according to the contractual standard, class requirement, approved test procedure, and stated pull / speed rating; test load and duration are to be confirmed.
• Electrical checks → verify insulation, protective devices, motor data, cable termination, control logic, local / remote operation, and enclosure protection according to project scope.
• Onboard maintenance → include the capstan in the vessel’s mooring-equipment inspection and maintenance plan, with clear operational markings and records retained as required.
• Wear points → monitor warping-head surface, corrosion, gearbox leakage, bearings, coupling, holding-down bolts, foundation cracks, cable damage, control switches, and any fitted brake or locking device.

Selection & Inquiry Guide

Step 1: Provide vessel type, mooring arrangement plan, installation position, required rated pull, required warping speed, and whether the capstan is for normal mooring only or another defined duty.

Step 2: Confirm rope type, construction, diameter, MBL / LDBF, minimum D/d requirement, expected line direction, nearby fairleads / rollers, and required warping-head diameter or profile.

Step 3: Confirm electric supply: voltage, frequency, phase, motor duty, single speed / two speed / VFD, required starting method, enclosure IP grade, insulation class, and hazardous-area requirement.

Step 4: Confirm control arrangement: local, remote, or both; emergency-stop points, control-station location, line-of-sight requirement, communication, and any brake / hold function.

Step 5: Provide foundation and deck data: mounting space, deck thickness, supporting stiffeners, bolt arrangement, rope lead height, allowable equipment envelope, and maintenance / removal access.

Step 6: Confirm coating, material requirements, quantity, class society, inspection / test scope, certificate requirement, delivery destination, required delivery time, and GA drawing if available.

Applications

Bow mooring station | Stern mooring station | Ship-side line-handling station | Merchant vessels | Tankers | Bulk carriers | Cargo vessels | Workboats | Barges | Tug and service vessels | Newbuilding and retrofit mooring systems

Certifications & Documentation

Class survey, product certification, material certificates, maker’s test certificate, factory acceptance testing, and witnessed load / function testing can be arranged according to the vessel class, flag requirement, approved drawing, and agreed inspection plan. These documents are not automatically included with every capstan.

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

Drawing & Photos

FAQ

Q1: What does “horizontal electric motor capstan” mean?

A1: It normally refers to the drive arrangement: the warping head is vertical, while the electric motor and gearbox are arranged horizontally, typically above deck. This differs from a through-deck vertical-drive capstan where the motor and gearbox may be installed below deck. The final arrangement should be confirmed from the GA drawing.

Q2: Is the capstan pull the same as the mooring line MBL or the equipment SWL?

A2: No. Rated capstan pull is the hauling force available at the warping head under specified operating conditions. Mooring-line MBL / LDBF, Ship Design MBL, WLL, fitting SWL, and foundation design loads are different values and must be selected and documented separately.

Q3: What information is most important for quotation?

A3: Confirm rated pull, warping speed, rope type and diameter, warping-head diameter, vessel electrical supply, single / two-speed / VFD requirement, local or remote control, installation foundation, class requirement, test and certificate scope, quantity, and delivery destination.