Piston Crowns

Are you looking for service for your Four Stroke Engine, Piston Crowns you’ve come to the right place!

PJ Diesel engineering A/S has more than 40 years’ experience in servicing, repairing and maintaining Piston Crowns and offer an Exchange system with a stock of Piston Crowns that can be dispatched and made available to our customers within 24 hours.

We focus on circular economy-based repair and service solutions based on “Waste Less – Lose Less” principle, and continuous optimization, so please contact us with specific application information and we will guide and advise accordingly.

Repair by Chrome Plating

Chrome plating is commonly used to strengthen or repair ring grooves and piston rings for 2- and 4-stroke engines. Chrome plating can be applied to a range of different base materials, which includes (but is not restricted to) any type of steel, grey cast iron, aluminium and aluminium alloys.

The main characteristics of hard chrome plating are:

    • High wear and corrosion resistance
    • Extremely high adhesive strength
    • Prevents cold welding, even at high temperatures
    • Homogenous layer structure
    • Neither toxic nor allergenic
    • Suitable for repair work
    • Layer hardness: usually 750-1,050 HV.

For a Piston Crown repair, the procedure of Hard Chrome Plating involves a serie of processes. The processes are conducted in the following sequence: pre-grinding, blasting => masking => hard chrome plating => final grinding.
This sequence can be seen in the figure beneath. After the repair, the sides of the ring grooves will be flat, parallel, and smooth with proper clearance of the ring to ensure a good seal.

Figure: Hard chrome plating sequence

Figure: Chrome plated groove – back to drawing dimensions for 27/38 
Approx. 900-1000 HV

After the repair, the chrome plated ring grooves will have a hardness of 900-1000 HV, approximately the double compared to the newly produced component, as well as the product repaired by laser cladding.
This gives an increased wear and corrosion resistance, resulting in a lifetime approximately 2-3 times more than the original component.

New is not necessarily best!
A Piston Crown with a wear and damages can in most cases be repaired at a price up to 75% less than buying a new one. It can even improve life cycles compared to new components from the manufacturer – and with even better delivery times.

Availability and fast response are key to our mutual success, and at the same time we can offer to repair parts which often would be stated as non-repairable. Common problems can most likely be repaired in our workshop and along comes always a 24-month liability for defects and shortages.

The PJ Diesel component workshop is located in Rødby, south of Copenhagen, and is specialized in the reconditioning of major engine components. We offer service, repair and maintenance of all types of Piston Crowns and we have a team of factory trained service engineers working around the clock to service our customers.


Circular flow and Exchange Service


Imagine a shared response program unlocking the value of unused assets and saving you from stockpiling key components for urgent repairs.

Within PJ Diesel Engineering A/S you can join services with other end-users minimizing stock expenses, and at the same time maintaining full flexibility and the advantage of externalizing the risks. Through our exchange program expensive individual ownership costs and delivery time is reduced with shared acknowledged access to key components. Read more about our EXCHANGE SERVICE

Long- and short-term benefits


    • Improving service by enabling programmed maintenance and emergency response
    • Reduce dependency from shore facilities
    • Eliminate delivery time (Time required for repairs from shore)
    • Plug and play solutions
    • Risk reduction
    • Reduced operational cost
    • Elimination of expensive inventory
    • Fixed prices on exchange units - easy budget planning
    • 24 months liability for defects and shortages
    • High availability because of inventory at PJ Diesel Engineering A/S facilities
    • Not stocking expenses
    • No new unit investment
    • Full report and IMO/EAIAPP Validation
    • Repairable damages all included in SEU (Service Exchange Unit) A solution with no extra costs
    • Elevating from supplier to service partner (Trusted supplier)
    • Responsible and sustainable Supply Chain Management