Hawse Pipe

medium 2 / 2 models (Inspector)

The hawse pipe is the cast steel tube through the bow shell plating that the anchor chain runs through and the anchor itself stows into; get its bore, curvature or bell mouth wrong and the anchor either will not stow flush or the chain chafes the shell plating on every heave.

What sets a hawse pipe apart

Unlike a chain locker or windlass, which handle the chain once it is inboard, the hawse pipe is the single point where the anchor chain crosses the hull shell plating, so it has two conflicting jobs at once: let the chain run freely with minimal wear, and keep the hull watertight around that opening. There are two common configurations - the bell mouth type, flared outward at the outboard end to guide the chain smoothly regardless of angle, and the pipe type with a straighter bore that relies more on the anchor pocket shape to seat the anchor correctly. The choice depends mostly on hull form forward and the anchor type fitted, since a stockless anchor needs the shell plating recessed into an anchor pocket that the flukes pull up against when fully hove home.

Hawse pipe at the bow — Side cross-section at the bow showing the hawse pipe running from the deck through the curved shell plating to a flared bell mouth, the stockless anchor stowed against the opening, the chain continuing down the spurling pipe into the chain locker below deck.

Main components

Outboard bell mouth or spigot - the flared or straight opening in the shell plating where the chain first enters, shaped to avoid sharp chain angles that cause wear.
Pipe body - the cast or fabricated steel tube running from shell plating through to the chain locker flat, sized to the chain diameter with clearance for the chain to run without jamming.
Anchor pocket / recess - a shaped recess in the shell plating, matched to the anchor's fluke profile, that the anchor seats into so it sits flush and does not project beyond the hull when stowed.
Inboard flange / chain locker connection - where the pipe terminates at the chain locker, sometimes fitted with a spurling pipe cover to keep water and spray out of the locker.
Wear liner - a replaceable liner in high-wear designs that takes the chain's abrasive contact instead of the pipe body itself.

Selection / Sizing

Bore diameter is set directly by the chain size fitted, per the classification society's anchor and chain tables based on the ship's equipment number, with enough clearance for the chain to run freely including when wet, iced or slightly distorted. The bend radius through the pipe has to stay within limits that avoid excessive chain-to-pipe wear and avoid the chain jamming when paying out or heaving in at an angle. Anchor pocket shape is matched to the specific anchor model and mass, since anchor manufacturers supply pocket templates - a generic pocket that does not match the anchor fitted will leave it sitting proud of the hull or jammed on stowing.

Regulations / Class

Class societies specify hawse pipe bore, wall thickness and material based on the ship's equipment number and the anchoring equipment fitted, as part of the anchoring and mooring equipment rules rather than a separate SOLAS requirement. The arrangement must keep the anchor properly housed to avoid damage to the shell plating and to avoid the anchor working loose in a seaway, which class surveyors check as part of periodic equipment surveys.

Typical faults

Fault	Consequence
Wear grooving in the pipe bore from years of chain contact	Chain runs less smoothly, wear accelerates further, eventually the pipe wall thins
Corrosion of the pipe body, especially at the waterline splash zone	Wastage that can progress to holing if not caught at survey
Anchor pocket mismatch or deformation	Anchor does not seat flush, vibrates or works loose in a seaway, can damage shell plating
Cracked welds between pipe and shell plating	Potential leak path into the chain locker or forepeak

What to look for in a supplier

Bore and bend radius calculated against the actual chain size and grade fitted, not a nominal ship-size table.
Anchor pocket profile confirmed against the specific anchor model's manufacturer template before fabrication.
Material and thickness suited to the wear duty expected, particularly on vessels with frequent anchoring operations.

Check the anchor sits fully flush in its pocket every time it is hove home - a proud anchor is not just cosmetic, it takes green water impact directly and can start a shell plating leak that only shows up as unexplained forepeak wetness weeks later.

Hawse pipe with anchor chain — Hawse pipe and anchor chain at the bow, seen in dry dock. Photo: Brosen, CC BY 2.5, via Wikimedia Commons

Inspector Mode Show All 2 / 2 with inspector value

1 manufacturers · 2 models

Generic (Class Approved)

Bell Mouth Hawse Pipe

For chain 58-97mm · Deck Hardware · bell mouth hawse pipe

Type

bell_mouth

Chain range (mm)

58-97

Common Failures & Inspection Points

Corrosion, wastage or coating breakdown causes visible section loss and weakens the fitting or surrounding structure
Wear in pins, rollers, hinges or bearing surfaces causes excessive play, stiffness or poor line guidance
Seal or gasket deterioration on closing appliances causes water ingress or loss of weathertight integrity
Loose foundations, fasteners or cracked welds cause movement, vibration or visible structural defects
Blocked drains, vents or passages cause water accumulation, pressure problems or restricted operation

Service: Inspect structural attachment, corrosion, welds, fasteners, moving parts, seals and coatings. Verify free movement, drainage, closing and securing functions according to the fitting type. Pay particular attention to load-bearing foundations and watertight or weathertight boundaries. Refer to class, vessel and manufacturer documentation for the exact figure for loads, clearances and acceptance limits.

Spare Parts: Carry seals or gaskets, pins, bushes, rollers, approved fasteners, lubrication items and small operating hardware appropriate to the installed fitting.

Strengths

Bell‑mouth profile reduces chain abrasion at the hull entry point
Wide chain size acceptance (58‑97 mm) covers most commercial anchor chains
Class‑approved design simplifies regulatory compliance and inspection
Simple weld‑on installation with a single penetration through the hull
Standard dimensions allow easy replacement on many vessel types

Weaknesses

Internal wear can still occur from chain abrasion over long service periods
Weld joint at hull penetration is a known location for cracking if not properly executed
Corrosion wastage may develop if protective coating is damaged or maintenance lapses
Requires periodic wall‑thickness measurement during dry‑dock surveys
Generic design offers limited customization (e.g., no integrated chain guide or wear plates)

Typical Vessels: TankerBulk CarrierContainer ShipGeneral Cargo VesselOffshore Supply Vessel

Decision Guide: Choose if: you need a standard, class‑approved hawse pipe for anchor chains between 58 mm and 97 mm, with straightforward installation and proven compatibility across many vessel classes. Avoid if: the vessel operates in highly abrasive or corrosive environments where enhanced wear‑resistant liners or integrated chain guides are required.

Use Cases: Mooring, deck access, cargo access, drainage, ventilation and general deck service.

Datasheet

Bolted Hawse Pipe

For chain 46-87mm · Deck Hardware · bolted hawse pipe

Type

bolted