Ferrous pistons for diesel engines having EGR coating
AssigneeFederal-Mogul World Wide, Inc.
InventorsTom Bedwell, Carmo Ribeiro, Miguel N. D. De Azevedo
Life of this patent
Estimating the term…
Abstract
A corrosion resistant piston for use in an exhaust gas recirculation diesel engine. The piston includes a crown portion having ring grooves formed around a periphery of the crown portion. The ring grooves are separated by ring lands. The piston also includes a piston rod connecting portion that extends from the crown portion. The piston is made of steel and includes an electroless coating of nickel having a maximum thickness of 8 micrometers.
Claims20
A piston for a diesel engine having exhaust gas recirculation, comprising:
- a piston body fabricated of ferrous metal having a plurality of ring grooves and pin bosses;
- and
- an EGR coating of electroless nickel formed on at least a portion of said piston body providing a continuous, non-porous barrier to the exhaust gas recirculation environment of the diesel engine.
A piston for a diesel engine having exhaust gas recirculation, comprising:
- a piston body fabricated of steel having a plurality of ring grooves and ring lands and a pair of pin bosses;
- and
- an EGR coating of electroless nickel formed on at least a portion of said piston body having a maximum thickness of about 8 micrometers and providing a continuous, non-porous barrier against the exhaust as recirculation environment of the diesel engine.
A method of making a piston for a diesel engine having exhaust gas recirculation, comprising:
- fabricating a piston body of ferrous metal;
- applying a continuous, non-porous electroless nickel coating to at least a portion of the piston body;
- and
- installing the piston body in the diesel engine with the coating in its as-applied condition.
A diesel engine comprising:
- an engine block having a cylinder bore in which exhaust gases are recirculated to provide a corrosive EGR environment;
- a ferrous piston disposed in said cylinder bore;
- and
- a continuous, non-porous coating of electroless nickel applied to at least a portion of said piston for providing a barrier against said corrosive EGR environment.
A diesel engine comprising:
- a combustion chamber;
- exhaust gas recirculation directing at least a portion of exhaust gases discharged from said combustion chamber back into said combustion chamber and presenting a corrosive EGR environment within said chamber;
- a power cylinder component fabricated of ferrous metal;
- and
- an EGR coating of continuous, non-porous electroless nickel applied to at least a portion of said component providing a protective barrier shielding said component from exposure to said EGR environment.
Dependencies are inferred from the claim text.