Piston Skirts - Main Engine and Propulsion

A piston skirt is the lower guiding section of a marine diesel engine piston assembly. It maintains alignment within the cylinder liner, provides a controlled running surface and withstands cyclic thermal and mechanical loads in propulsion engines.

ProShipWorks provides end-to-end support to source and supply Piston Skirts for marine vessels, ship operators, industrial facilities, maintenance teams and procurement departments.

Last updated: October 11, 2026

Product Information

Product Name	Piston Skirts
Product Category	Main Engine and Propulsion
Product Reference	313
Brands / Manufacturers	MAN Energy Solutions, WinGD, Wärtsilä
Unit of Measure	Piece

Key Features

Key Feature
1. Engine-specific machined geometry and clearances
2. Wear-resistant construction suitable for cylinder liner contact
3. May incorporate replaceable bronze or metallic rubbing bands
4. Designed for high cyclic thermal and mechanical loading
5. Lubrication grooves and surfaces support controlled oil distribution

Applications of Piston Skirts

Application
1. Low-speed two-stroke marine main propulsion engines
2. Piston assembly overhaul and reconditioning
3. Replacement of worn, cracked or scuffed piston skirts

Models & Manufacturers

Model	Manufacturer
MAN B&W S50MC-C	MAN Energy Solutions
Wärtsilä 6RTA58T	Wärtsilä
WinGD X52	WinGD

Technical Specifications

Model	Specification	Value	Unit
MAN B&W S50MC-C	Compatible nominal cylinder bore	500	mm
Wärtsilä 6RTA58T	Compatible nominal cylinder bore	580	mm
WinGD X52	Compatible nominal cylinder bore	520	mm

Standards, Certifications & Class Approval

Review the available standards and approval information relevant to the product. Actual certification, material traceability, inspection and classification requirements depend on the product type, intended application and purchasing specification.

Applicable Standards & Certification	No universal standalone certification applies to piston skirts. Material, dimensions, tolerances, nondestructive testing and acceptance criteria must follow the engine manufacturer's drawings, overhaul manual and applicable class rules.
Class Approval	Piston skirts are normally accepted as components of a class-approved engine design. Replacement or reconditioned parts may require documentation or survey acceptance from DNV, ABS, Lloyd's Register, Bureau Veritas or ClassNK, depending on vessel class requirements.

Installation, Maintenance & Safety Information

Installation Notes	Confirm engine type, bore, mark number and OEM part reference. Clean all mating surfaces, verify skirt-to-liner clearance and orientation, renew specified fasteners or locking devices, and tighten in the prescribed sequence to OEM torque values.
Maintenance Tips	Inspect for scuffing, cracks, distortion, excessive wear and loose or damaged rubbing bands. Measure diameter, ovality and liner clearance at OEM-defined points. Use approved nondestructive testing and replace parts outside service limits.
Safety Notes	Isolate the engine, engage turning-gear interlocks and follow enclosed-space and lifting procedures. Piston assemblies are heavy; use certified lifting tools and designated lifting points. Do not reuse damaged fasteners or operate with clearances outside OEM limits.