JIS F 2031 Casting Steel Pawl Type Chain Stopper Ship Mooring Equipment

Product Specification

Cast Steel Pawl Type Anchor Chain Stopper | JIS F 2031 for U2 / U3 Anchor Chain

Product Overview

The JIS F 2031 cast steel pawl type anchor chain stopper is a deck anchoring device installed between the anchor windlass and hawse pipe to clamp and secure the anchor chain. It is used to hold the chain during sailing, anchoring, and anchor stowage, so that a major part of the chain holding load can be transferred through the stopper foundation instead of being carried only by the windlass brake.

This pawl type chain stopper is different from an anchor chain roller wheel or chain guide. The roller wheel mainly adjusts chain direction, while the pawl type chain stopper is a load-holding component for U2 / U3 anchor chains. Selection should be checked together with chain size, chain grade, minimum breaking strength, windlass arrangement, deck foundation, installation drawing, and classification society requirement.

Quick Specifications

• Product type: cast steel pawl type anchor chain stopper → chain holding device for anchor windlass arrangements, not a chain roller guide.
• Standard: JIS F 2031:1998 → reference for pawl type chain stopper dimensions, nominal size selection, and Type A / Type B configuration.
• Applicable anchor chain: U2 / U3 anchor chain, 58–122 mm → suitable for medium and large ship anchoring systems within the supplied size range.
• Nominal size range: 60 to 122 → selected according to chain diameter, chain grade, and vessel anchoring arrangement.
• Approximate weight: 401 kg to 2900 kg → important for handling, lifting arrangement during installation, packing, and freight planning.
• Installation position: between windlass and hawse pipe → helps secure the anchor chain and reduce load demand on the windlass brake when properly integrated.
• Construction focus: cast steel body, pawl engagement, chain seating surface, pin / hinge fitting, and foundation load transfer → key inspection points for quotation and approval.
• Surface treatment: Sa 2.5 blasting + one layer epoxy shop primer as reference → final coating system should follow vessel painting specification or shipyard requirement.

Main Technical Parameters

Selection & Inquiry Guide

• Step 1: Confirm JIS F 2031 cast steel pawl type chain stopper, Type A or Type B, and nominal size 60 to 122 according to anchor chain diameter and vessel drawing.
• Step 2: Confirm anchor chain grade and chain size, including U2 / U3 requirement, minimum breaking strength, and any project-specific class rule basis.
• Step 3: Confirm installation position between windlass and hawse pipe, chain lead direction, stopper foundation, deck reinforcement, and available deck space.
• Step 4: Confirm material and traceability requirement: cast steel body, pawl / pin material, forged or fabricated fittings, material certificate level, and inspection scope.
• Step 5: Confirm surface treatment: shop primer, final paint system, galvanized / special coating request, corrosion allowance, or stainless steel accessory requirement if specified.
• Step 6: Provide quantity, destination, required delivery time, classification society requirement, GA drawing, chain arrangement drawing, and reference photos if available.

Structure

Cast steel stopper body | Pawl locking arrangement | Chain seating groove | Hinge / pin assembly | Foundation load-transfer interface | Type A / Type B radius form | Shop primer or specified coating

Chain Stopping, Installation & Engineering Advantages

• Pawl engagement provides a mechanical chain holding function for anchor chain securing, while the final holding capacity and approval basis should be checked against chain minimum breaking strength and class requirement.
• The cast steel body is suitable for large chain diameters and compact deck anchoring arrangements where the stopper must transfer chain force into the supporting hull structure.
• The chain seating surface and pawl contact area should be dressed and checked to reduce abnormal local contact, chain jump risk, and unnecessary wear during operation.
• The stopper foundation interface should be reviewed together with deck reinforcement, welding / bolting arrangement, and load path into the bow structure before installation.
• Pin, hinge, and pawl fitting clearances are important for reliable opening, closing, and inspection; lubrication and corrosion protection should be considered in the maintenance plan.
• When the chain stopper is properly arranged, the windlass brake and drive system can be designed and verified under the relevant windlass / stopper load cases required by the project.
• Material traceability, visual inspection, dimensional inspection, and non-destructive testing can be arranged according to order scope and classification society requirement.

Custom Attributes

• Standard: JIS F 2031:1998 → use when the shipyard or owner specification calls for JIS chain cable stopper dimensions.
• Type: Casting steel pawl type, Type A / Type B → select according to the project drawing and standard configuration.
• Nominal Size: 60 / 64 / 68 / 73 / 78 / 84 / 90 / 95 / 102 / 107 / 114 / 122 → select by anchor chain diameter and vessel anchoring arrangement.
• Applicable Chain: U2 / U3 anchor chain, 58–122 mm → chain grade, minimum breaking strength, and certificate requirement should be confirmed before quotation.
• Material: cast steel body with mild steel, C-Mn steel, casting steel, or forging C-Mn steel components as specified → exact grades and traceability level to be confirmed.
• Installation: between windlass and hawse pipe → stopper foundation, deck reinforcement, chain lead, and operation clearance should be confirmed by drawing.
• Surface Treatment: Sa 2.5 blasting + epoxy shop primer as reference → final coating follows vessel paint specification or shipyard request.
• Certificate Requirement: available according to project requirement → class inspection, material certificate, and witness test scope should be confirmed before order.

How It Works

Anchor chain is led from the hawse pipe toward the windlass → Chain link sits in the stopper seating area → Pawl is closed and secured over the chain → Chain holding load is transferred through the stopper body and foundation → Windlass brake and drive system are relieved according to the approved anchoring arrangement

Applications

Ocean-going vessels | Bulk carriers | Tankers | Container vessels | General cargo ships | Bow anchoring stations | Anchor windlass arrangements | Newbuilding projects | Repair and replacement of chain stoppers

Certifications & Advantages

Certificates can be arranged according to project requirement, inspection scope, material traceability, and class society approval procedure.

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

Drawing & Photos

FAQ

Q1: What is the difference between a pawl type chain stopper and an anchor chain roller wheel?

A1: A chain roller wheel mainly guides or changes the direction of the anchor chain. A pawl type chain stopper is a chain holding device used to clamp and secure the chain, and it must be checked according to chain size, chain grade, deck foundation, and approval requirement.

Q2: Does the 45% / 80% windlass load basis mean the product has a fixed SWL?

A2: No. The 45% / 80% figures are windlass and chain stopper design load cases used in anchoring arrangements. They should not be written as a fixed product SWL without confirming the chain minimum breaking strength, class rule basis, test method, and approval scope.

Q3: What information is needed before quotation?

A3: Confirm JIS F 2031 type, nominal size, anchor chain diameter, chain grade, minimum breaking strength, material grade, surface treatment, quantity, certificate requirement, installation drawing, delivery destination, and required delivery time.