JIS F 2030 Type A Single Point Mooring Chock | Oval Bow Bulwark Rope Guide

Product Overview

The JIS F 2030 Type A single point mooring chock, also described in the standard terminology as a single point mooring pipe, is a large cast rope-guiding fitting installed in the vessel bow bulwark. Its oval opening provides a smooth passage for a mooring hawser or rope as the line is led between the outboard single point mooring arrangement and the shipboard securing equipment.

Type A is the non-inclined oval configuration in the supplied product description, while Type B is the inclined oval configuration. The Type A series covers nominal sizes 400 to 800 mm and reference calculated masses from 210 to 880 kg. Selection must be based on the approved vessel mooring arrangement, rope construction and diameter, line lead direction, local bulwark reinforcement, and project classification requirements. This is a shipboard chock/rope guide; it is not the offshore single point mooring buoy system itself.

Quick Specifications

• Standard and type: JIS F 2030-1978 Type A → oval, non-inclined single point mooring pipe/chock for bow bulwark installation.
• Nominal size range: 400 / 500 / 600 / 700 / 800 mm → five sizes for matching the rope passage, vessel layout, and approved mooring arrangement.
• Reference calculated mass: 210-880 kg → important for casting handling, installation planning, lifting arrangements, packing, and freight.
• Material options: cast C-Mn steel, cast stainless steel, or project-specified special steel → exact grade, impact properties, and traceability must be confirmed.
• Rope-contact geometry: large oval opening with rounded radii → intended to guide the mooring line while reducing sharp local contact and chafing risk.
• Surface treatment: abrasive blast cleaning to Sa 2½ + one coat epoxy shop primer for carbon steel → final coating follows the vessel paint specification.
• Stainless steel option: polished rope-contact and exposed surfaces → polishing grade and final roughness are confirmed by the purchase specification.
• Certificate scope: maker documentation or class inspection → available according to project requirement and subject to drawing approval and survey arrangement.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm JIS F 2030 Type A and nominal size 400, 500, 600, 700, or 800 according to the approved vessel arrangement and required rope passage.

Step 2: Provide rope type, construction, nominal diameter, MBL, chafe-chain or hawser-end arrangement if applicable, and expected horizontal and vertical lead directions.

Step 3: Confirm the bow bulwark opening, installation elevation, available clearances, welding interface, local reinforcement, and relationship to bitts, chain stopper, or mooring equipment.

Step 4: Confirm material: cast C-Mn steel, cast stainless steel, or special low-temperature/ice-service steel. State the exact grade, impact-test temperature, heat treatment, and traceability requirement.

Step 5: Confirm surface treatment, rope-contact finishing, coating system, NDE scope, dimensional inspection, certificate requirement, and any class surveyor witness points.

Step 6: Provide quantity, vessel type, installation drawing, classification society, destination, required delivery time, and reference photos or existing replacement dimensions.

Structure

Oval cast body | Non-inclined Type A rope passage | Smooth rope-contact radii R and R1 | Bulwark-mounted welded interface | Reinforced casting sections | Carbon-steel coating or polished stainless-steel finish

Mooring, Casting and Installation Advantages

• The oval opening provides a large rope passage for bow single point mooring arrangements and accommodates the stated reference rope ranges without introducing a sharp edge at the bulwark opening.
• Rounded rope-contact radii help guide the hawser or rope and reduce local bending and abrasion compared with an unfinished plate opening; actual line wear also depends on lead angle, rope construction, tension, movement, and surface condition.
• The five nominal sizes allow the ship designer to coordinate the chock opening with rope diameter, line lead, bulwark geometry, and the surrounding mooring equipment rather than selecting by vessel size alone.
• For cast C-Mn steel, manufacturing control should focus on chemical and mechanical properties, heat treatment, casting soundness, dimensional accuracy, repair-welding control, and smooth dressing of the rope-contact surface.
• For cast stainless steel, the exact grade, casting process, corrosion environment, weld compatibility, heat treatment, pickling/passivation, and polishing requirement must be confirmed before production.
• The chock transfers rope-contact forces into the welded bulwark and supporting structure. The shipyard or vessel designer must verify the local load path, reinforcement, weld size, surrounding plate thickness, and allowable lead directions.
• Large sizes and masses require a controlled handling and installation plan, including temporary lifting points or approved slinging arrangements, fit-up tolerance, welding sequence, and post-weld inspection.
• Classification inspection, material certification, NDE, and final acceptance can be arranged to the agreed project scope; they are not automatically included unless specified in the purchase order.

Custom Attributes

• Standard: JIS F 2030-1978 → customer-stated dimensional and type reference; current project acceptance and original figure must be confirmed.
• Type: Type A oval, non-inclined configuration → differentiate from the Type B inclined oval configuration.
• Nominal Size: 400 / 500 / 600 / 700 / 800 mm → select by rope passage, lead direction, installation space, and vessel drawing.
• Material: Cast C-Mn steel / cast stainless steel / special steel → exact grade and component-specific properties are order-specific.
• Reference Mass: 210-880 kg → supports handling, installation, and logistics planning; final weight follows approved drawing and actual material.
• Surface Treatment: Sa 2½ + epoxy shop primer or polished stainless steel → final coating/polishing system must be specified.
• Installation: Bow bulwark welded arrangement → local structure, weld details, reinforcement, and access remain the shipyard or designer responsibility.
• Certificate Requirement: Maker certificate or class certificate according to order → subject to class approval, inspection scope, and survey arrangement.

How It Works

Mooring hawser approaches the bow → Line passes through the oval Type A chock → Smooth radii guide the line and limit sharp local contact → Rope force is transferred through the cast body and welded bulwark structure → Line is secured by the approved shipboard mooring arrangement

Applications

Large commercial vessels | Tankers fitted for single point mooring | Bulk carriers | Bow mooring stations | Temporary offshore mooring operations | Newbuilding projects | Replacement of JIS F 2030 Type A mooring pipes

Certifications & Advantages

Material certificates, dimensional inspection records, NDE reports, and classification inspection can be arranged according to project requirement. Classification approval and survey scope must be confirmed before quotation and are subject to the approved drawing and applicable class rules.

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

Drawing & Photos

FAQ

Q1: What is the difference between JIS F 2030 Type A and Type B?

A1: According to the supplied product description, Type A is the oval non-inclined configuration and Type B is the oval inclined configuration. The final choice depends on the vessel bow geometry, rope lead, installation position, and the original standard or approved project drawing.

Q2: Can the reference rope table be used as the only selection basis?

A2: No. The reference diameters are an initial dimensional guide. Final selection must also consider rope construction and MBL, chafe-chain or hawser-end arrangement, line lead angles, dynamic loading, contact pressure, local bulwark strength, and class/owner requirements.

Q3: What information is required for a class-approved quotation?

A3: Provide the original JIS or vessel drawing, nominal size, material grade, rope data, installation and reinforcement drawing, coating or polishing specification, NDE and test scope, certificate requirement, quantity, destination, and required delivery schedule.