Cast Steel Closed Chocks for Barges & Workboats | ASTM A27 Grade 70-36

Product Specification

Cast Steel Closed Chocks for Barges & Workboats | ASTM A27 Grade 70-36

Product Overview

The ASTM A27-70-36 cast steel closed chock is a deck-mounted mooring rope guide developed for American inland barges, river workboats, small service vessels, and similar vessels operating in the Americas market. It provides a closed rope passage to help keep mooring line or wire close to the deck and guide the line through a smooth cast-steel contact surface during barge mooring, shifting, and deck handling operations.

This page covers the 480, 490, and 14 closed chock sizes with inch-based dimensions. The chock body is supplied in C-Mn cast steel ASTM A27 Grade 70-36 or equivalent, with heat treatment and casting quality control according to the order requirement. Magnetic particle testing, dye penetrant testing, strength calculation, and pull testing can be arranged when the customer specifies the inspection scope, loading direction, and acceptance criteria.

Quick Specifications

• Product type: Cast steel closed chock → closed rope or wire guide for American barge and small-vessel mooring arrangements.
• Typical market: U.S. and Americas inland barges, workboats, and small vessels → not positioned as a large ocean-going ship chock without project verification.
• Models: 480 / 490 / 14 → three inch-dimension sizes commonly used for 9 in, 12 in, and 14 in closed chock arrangements.
• Clear opening: 6 × 12 in, 8 × 16 in, and 9.38 × 18.75 in → key selection point for line passage and deck layout confirmation.
• Material: ASTM A27 Grade 70-36 cast steel or equivalent → suitable for cast carbon steel deck fittings when the project accepts this material grade.
• Weight range: 176–725 lb (80–329 kg) → useful for handling, freight estimation, and shipyard installation planning.
• Surface treatment: sandblasting as supplied reference → final paint, bare weldable surface, or other finish should be confirmed before order.
• Quality control: material mechanical test, heat treatment record, MT / PT inspection, strength calculation, and pull test can be arranged according to project scope.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm the model: 480, 490, 14, or customized drawing-based closed chock.

Step 2: Confirm vessel type and application: American inland barge, workboat, small vessel, or replacement deck hardware.

Step 3: Confirm rope or wire path, line size, clear opening requirement, deck arrangement, and whether the line must be kept low near the deck.

Step 4: Confirm installation position, deck plate thickness, welding interface, local reinforcement, and available space around the chock.

Step 5: Confirm material and inspection scope: ASTM A27-70-36 or equivalent, heat treatment, material certificate, MT / PT, strength calculation, pull test, and ABS approval requirement.

Step 6: Confirm surface treatment, quantity, delivery destination, required delivery time, drawing or photo, and any customer-specific acceptance criteria.

Structure

One-piece cast steel closed body | Smooth rope-contact opening | Deck-welded base | Rounded entry edge | Reinforced side wall around rope passage | Heat-treated cast steel | Sandblasted or specified surface finish

Casting, Testing & Engineering Advantages

• ASTM A27 Grade 70-36 cast steel or equivalent is used as the material reference, with heat treatment and mechanical testing scope confirmed according to the purchase order.
• The closed chock body is cast as an integral rope guide, reducing sharp fabricated joints around the rope-contact opening.
• Rope-contact surfaces are dressed and smoothed after casting to remove burrs that may damage mooring ropes or wire during operation.
• Casting quality can be controlled through visual inspection, dimensional checking, heat treatment record review, and material mechanical test.
• Magnetic particle testing or dye penetrant testing can be arranged when required; RT / UT or other NDE methods should be specified if internal soundness inspection is required.
• Strength calculation or FEA review can be prepared for project approval when the customer provides load direction, line load, deck support condition, and installation drawing.
• Pull testing can be arranged according to the customer-defined test load, loading direction, fixture arrangement, and inspection acceptance criteria.
• The product is written for American barge and small-vessel deck hardware use, avoiding unsupported claims for large ocean-going vessel mooring loads.

Custom Attributes

• Product Category: Cast steel closed chock → closed rope or wire guide for barge deck mooring hardware.
• Main Application: U.S. and Americas inland barges / small vessels → suitable where inch-based American deck fitting dimensions are required.
• Model Range: 480 / 490 / 14 → select by clear opening, available deck space, and vessel drawing.
• Material Grade: ASTM A27 Grade 70-36 or equivalent → C-Mn cast steel material reference for cast deck fittings.
• Surface Finish: Sandblasting → final coating, bare weldable finish, or other surface treatment should be confirmed by the customer.
• Inspection: Material test, heat treatment record, MT / PT, strength calculation, and pull test available → exact acceptance criteria must be confirmed before quotation.
• Certificate Scope: ABS approval and Mill’s material certificate available according to order → class approval and witness inspection are subject to project requirement.
• Load Data: To be confirmed → no SWL, MBL, proof load, or test load is declared in the supplied parameter table.

How It Works

Mooring line or wire approaches the deck chock → Line passes through the closed cast-steel opening → Smooth rounded contact surface guides the line and helps keep it close to deck level → Local force is transferred through the cast body and welded base into the deck structure → Inspection, repair, and coating are completed according to the shipyard procedure

Applications

American inland barges | River barges | Towboat deck hardware | Workboats | Small service vessels | Barge mooring stations | Americas market replacement deck fittings

Certifications & Advantages

ABS approval, Mill’s material certificate, NDT report, strength calculation report, and pull test report can be arranged according to project requirement, inspection scope, and approval procedure.

Certification: CCS, NK, BV, ABS, DNV, LR, KR, IRS, RS, RINA, CRS, Makers Test Certificate — available only when specified and subject to project requirement / class approval.

Drawing & Photos

FAQ

Q1: Is this cast steel closed chock suitable for all ships?

A1: No. This page is focused on American inland barges, workboats, small vessels, and similar Americas-market deck hardware. For large ocean-going ships, the vessel designer should confirm the load, rope size, foundation, applicable standard, and class requirement before selection.

Q2: How should Model 480, 490, or 14 be selected?

A2: Select by clear opening, mooring line or wire path, available deck space, installation drawing, and replacement requirement. Model 480 provides a 6 × 12 in clear opening, Model 490 provides an 8 × 16 in clear opening, and Model 14 provides a 9.38 × 18.75 in clear opening.

Q3: What inspection or testing can be supplied?

A3: Material mechanical test, heat treatment record, magnetic particle testing, dye penetrant testing, strength calculation, and pull testing can be arranged according to order scope. Test load, loading direction, acceptance criteria, and witness inspection requirement should be confirmed before quotation.