Piston Skirts

At YAF Engineering, we provide comprehensive reconditioning services for piston crowns and skirts, ensuring high-performance operation and extended component lifespan under the most demanding conditions. Piston components are subject to extreme thermal and mechanical stress, making proper inspection and precision restoration essential.

Typical issues encountered include:

Excessive wear of piston grooves
Thermal cracks on the combustion surface
Cracking or flaking of the chrome plating layer

Inspection process:

Each piston crown received in our workshop undergoes chemical cleaning and shot blasting before entering a detailed inspection process that includes:

Dimensional measurements and visual examination
Leptoscope testing to measure chrome layer thickness
Dye penetrant inspection to detect surface cracks
Preparation of a comprehensive technical report with reconditioning recommendations

Standard piston crown reconditioning procedure:

Pre-machining of grooves and outer diameter
Submerged arc welding to rebuild worn piston grooves and crown diameter
Heat treatment (annealing) in digitally controlled ovens
CNC machining of oversize grooves and chrome prep
Hard chrome plating of grooves (0.5 mm per side)
Precision grinding to standard dimensions, ensuring groove surface parallelism

Additionally, we offer cladding of the top surface with Inconel for enhanced resistance to wear and thermal fatigue.

For piston skirts, worn copper bands are renewed and machined back to OEM dimensions after thorough inspection.

All procedures are performed in-house using automated welding systems, preheating, annealing furnaces, chrome plating baths, and specialized grinding machines—ensuring a fully restored and performance-ready result.