PL | EN | RU


ul. Liściasta 17
91-357 Łódź
tel 042 617 41 23
fax 042 650 71 61


In order to improve operating properties of the piston rings and increase its resistance to corrosion, FPT Prima Company uses the following surface treatment of the rings:

- soft, ie iron-zinc phosphatizing,  iron-manganese phosphatizing  and tin plating

-hard, ie applying the coating: Ferrox, Cr, PCA, Mo, Plasma

Soft coatings allow a better fit of interacting elements - piston ring and cylinder during engine start and reduce the time of the rings running-in.

Hard coatings are coatings used primarily to extend the life of the ring.


Ferrox Type Coating.                                                                                                    

This process involves the use of a porous structure mass called Ferrox, filling the grooves on the track of the piston ring. At the same time Ferrox lubricates the oil tank, lowering friction during movement of the ring on the cylinder lining. This is important especially when the engine is operating in a two-stroke cycle.


Cr Coating

Chrome plate coatings are applied galvanically. They are widely used because of the very favorable properties and high hardness. Very high wear resistance against wear and chipping in their time of service are the main advantages.A limitation of the use of chromium coating is its susceptibility to burnings in engines, which are heavily loaded thermally. In addition, plating processes are cumbersome because of the difficulty of meeting requirements for environment protection.


PCA Coating

Chrome - ceramic coatings (Cr + Al2O3) type PCA (by Prima) applied galvanically have more favorable properties compared to chromium coatings in terms of taking of major mechanical or thermal loads. It has very high resistance to its own wear, high thermal workload, low wearing of the cylinder lining, resistance to burning, and abrasion resistance PCA is a 3-times higher than normal chromium coating. It is used as a durability coating for piston rings of diesel engines.


Mo Molybdenum Coating

This coating is flame sprayed molybdenum plating. Spray material is molybdenum wire.

Molybdenum coating compared to the plasma AMDRY 1371 plating is porous, hard and features good self-lubricating properties. It is characterized by high resistance to its own wear and a very high resistance to burns.   It is susceptible to chipping due to high porosity. The coating is used as a durability coating for piston rings designed for engines operating in less favorable lubrication conditions.


Amdry 1371 (Sulzer - Metco) Plasma Coating

This plating is metal - ceramic-based molybdenum with nickel and chromium mixed coating. In comparison to pure molybdenum the plating features: less porosity, less hardness, resistance to burning and seizing traces formation, higher mechanical strength, high resistance to its own abrasive wear, low cylinder lining wear, better adhesion to the base, and low self-lubricating properties. It is used as a durability coating applied on the piston rings for:

-heavy duty engines, thermally loaded and high-speed diesel

-motors with good lubricating properties (working with a very good oil)