150–500 mm Cast Steel Mooring Roller without Upper Dust Cover | ISO 13755:2020 Type A

Product Overview

The ISO 13755 Type A cast steel mooring roller is a single vertical rope-guiding fitting used in shipside roller fairlead and pedestal fairlead arrangements. As the mooring line changes direction, the roller turns around its axle to reduce sliding abrasion at the rope-contact surface, while the resulting load is transmitted through the bush, axle, foundation, welding connection, and supporting hull structure.

Type A is the cast steel configuration without an upper dust cover, giving direct access for visual inspection and lubrication. ISO 13755:2020 is the current edition and replaces ISO 13755:2012. For quotation and production, the required edition, nominal size, rope lead arrangement, D/d ratio, reference SWL, foundation design, material, coating, and certificate scope should be confirmed from the vessel drawing and project specification.

Quick Specifications

• Product type: Single cast steel mooring roller fairlead -> guides and redirects a ship mooring line through a rotating rope-contact surface.
• Standard and type: ISO 13755 Type A -> cast steel roller without upper dust cover; ISO 13755:2020 is the current edition.
• Nominal size range: Dn 150 / 200 / 250 / 300 / 350 / 400 / 450 / 500 mm -> nominal size is referenced to the roller outside diameter.
• Reference SWL range: 265 to 1,942 kN at theta = 90 degrees and 186 to 1,373 kN at theta = 0 degrees -> standard reference values; actual marked SWL depends on the agreed loading and installation condition.
• Calculated Type A mass: 23 to 360 kg/set -> correct range for handling, packing, installation planning, and freight estimation.
• Standard material basis: Cast steel roller with yield point not less than 205 N/mm2; axle not less than 350 N/mm2; brass, bronze, or equivalent bush.
• Rope-contact and maintenance: Smooth contact surface, anti-corrosion finish, and greased rotating parts -> supports rope protection and free roller movement.
• Installation basis: Foundation, welding connection, and under-deck reinforcement must be checked for the selected load and hull arrangement.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm ISO 13755 Type A and state whether the project requires the current 2020 edition or a legacy 2012 drawing for replacement compatibility.

Step 2: Select nominal size Dn according to the vessel mooring arrangement, available installation space, rope diameter, and the rope manufacturer's allowable D/d bend ratio.

Step 3: Confirm the rope lead direction and applicable theta load case, required marked SWL, foundation or pedestal arrangement, under-deck reinforcement, and welding interface.

Step 4: Confirm material: standard cast steel roller, axle material, bush material, or any non-standard stainless steel / special material option subject to engineering review.

Step 5: Confirm surface treatment, final paint system, lubrication arrangement, inspection scope, material traceability, and classification society requirement before quotation.

Step 6: Provide quantity, vessel type, installation position, drawing or reference photo, delivery destination, and required delivery time.

Structure

Cast steel roller | Axle | Brass / bronze bush | Grease path and lubrication point | No upper dust cover | Foundation / seat | Welded connection to ship structure

Casting, Rope Contact & Installation Advantages

• Type A uses a cast steel roller body without the upper dust cover fitted to Type B, allowing direct access to the upper axle and bush area for inspection and lubrication.
• The rotating roller changes the rope direction with less sliding contact than a fixed guide surface, helping reduce abrasion when the roller remains freely rotating and correctly lubricated.
• Rope-contact surfaces should be smooth and free from roughness or irregularities that could damage the mooring line by abrasion.
• ISO 13755 uses separate assembly details for nominal sizes 150-250 and 300-500, so replacement enquiries should include the nominal size and existing arrangement drawing.
• The current standard adds D/d ratio guidance: roller contact diameter and rope diameter should be reviewed together because excessive bending can reduce rope strength.
• The foundation and welding connection must transmit the selected maximum loading into the hull structure without plastic deformation or cracking; local deck or pedestal reinforcement is therefore part of the installation check.
• External anti-corrosion protection and greasing of rotating parts are required functional controls; final coating build-up, grease type, and maintenance interval should follow the project specification.

Custom Attributes

• Standard Edition: ISO 13755:2020 recommended for new enquiries -> current published edition with updated SWL wording and D/d guidance.
• Legacy Edition: ISO 13755:2012 -> use only when an existing vessel drawing, replacement item, or project specification expressly requires the earlier edition.
• Type: Type A without upper dust cover -> distinguish from Type B cast steel with cover and Type C steel plate construction with cover.
• Nominal Size: Dn 150-500 mm -> select together with rope size, line path, installation space, and reference SWL.
• Reference SWL: Two standard load cases by theta angle -> actual marked value is agreed according to the real loading and installation condition.
• Standard Material Basis: Cast steel roller >=205 N/mm2 yield; axle >=350 N/mm2 yield; brass / bronze / equivalent bush.
• Alternative Material: Cast stainless steel or special material to be confirmed -> requires review of strength, weldability, corrosion behavior, machining, and approval basis.
• Surface Treatment: Sa 2.5 blasting plus epoxy shop primer can be used as a project reference -> final coating system and DFT follow the vessel paint specification.
• Certificate Requirement: Available according to order scope -> confirm maker certificate, material certificate, class survey, witness inspection, and final marking before quotation.

How It Works

Mooring line approaches the roller -> Rope bears on the smooth cast steel contact surface -> Roller rotates around the axle and bush -> Line direction changes with reduced sliding abrasion -> Load transfers through the foundation and welded hull structure -> Lubrication and inspection maintain free rotation

Applications

Shipside roller fairlead arrangements | Pedestal fairleads | Ship deck mooring stations | Mooring line direction changes | Newbuilding projects | Replacement and repair projects

Certifications & Advantages

Certificates can be arranged according to project requirement, material traceability, inspection scope, and classification society approval procedure. Availability is subject to order scope and class acceptance.

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

Drawing & Photos

FAQ

Q1: Should a new enquiry use ISO 13755:2020 or ISO 13755:2012?

A1: ISO 13755:2020 is the current edition and replaces the withdrawn 2012 edition. A legacy 2012 basis should be used only when the vessel drawing or replacement requirement specifically calls for it. State the required edition in the enquiry.

Q2: How should the nominal size and SWL be selected?

A2: Select Dn together with the rope diameter, D/d bend ratio, rope lead direction, theta load case, vessel mooring plan, foundation, and under-deck reinforcement. The table SWLs are reference values; the actual marked SWL is agreed for the real loading and installation condition and must not exceed the standard value.

Q3: What maintenance is important for Type A without a dust cover?

A3: Check that the roller turns freely, keep the axle and bush lubricated, inspect the exposed upper area for contamination or corrosion, and examine the rope-contact surface for roughness or damage. Type B should be considered when the project specifically requires an upper dust cover.