Cylinder head and method of reconstructing same

Claim 2

A cylinder head for a large internal combustion engine comprising a body member adapted to provide a combustion surface at one end, a water jacket portion adjacent said combustion surface, said water jacket portion having both upper and lower walls, a plurality of apertured bosses extending through said water jacket portion and providing ports opening into said combustion surface, bolt holes located around the periphery of said body member, said lower wall of said water jacket portion comprising an insert of an iron alloy containing chromium and having substantially the same coefficient of expansioN as the material of said body member, the peripheral edges of said insert being spaced inwardly from said bolt holes, said body member being recessed to accommodate said alloy insert, and the lower surface of said insert providing a combustion surface for said cylinder head of said iron-chromium alloy material, said insert being brazed to the adjacent surface portions of said recessed body member, said alloy insert providing the lower portions of said port bosses and being brazed to the upper portions thereof.

Claim 3

A cylinder head as claimed in claim 1 in which the insert is an alloy having a chromium content of 4-22 percent by weight, a nickel content of 0-60 percent by weight, a carbon content of 0.2-2.1 percent by weight, and the balance predominantly iron.

Claim 4

A cylinder head for a large internal combustion engine comprising a body member adapted to provide a combustion surface at one end, a water jacket portion adjacent said combustion surface, said water jacket portion having both upper and lower walls, an injector boss and a plurality of valve port bosses extending through said water jacket portion and providing ports opening into said combustion surface, bolt holes located around the periphery of said body member, water ports located around the periphery of said body member for communication with the water cavity of a cylinder liner, said lower wall of said water jacket portion comprising an insert of an iron alloy containing chromium having substantially the same coefficient of expansion as the material of said body member, the peripheral edges of said insert being spaced inwardly from said bolt holes and water ports, said body member being recessed to accommodate said alloy insert, and the lower surface of said insert providing a combustion surface for said cylinder head of an iron-chromium alloy material, the peripheral portion of said insert being brazed to the adjacent surface portions of said recessed body member, said alloy insert providing the lower portions of said injector and valve port bosses and being brazed to the upper portions thereof.

Claim 5

A cylinder head for a large internal combustion engine comprising a body member adapted to provide a combustion surface at one end, a water jacket portion adjacent said combustion surface, said water jacket portion having both upper and lower walls, an injector boss and a plurality of valve port bosses extending through said water jacket portion and providing ports opening into said combustion surface, bolt holes located around the periphery of said body member, water ports located around the periphery of said body member for communication with the water cavity of a cylinder liner, said lower wall of said water jacket portion comprising an insert of an iron alloy containing chromium having substantially the same coefficient of expansion as the material of said body member, the peripheral edges of said insert being spaced inwardly from said bolt holes and water ports, said body member being recessed to accommodate said alloy insert, and the lower surface of said insert providing a combustion surface for said cylinder head of an iron-chromium alloy material, the peripheral portion of said insert being brazed to the adjacent surface portions of said recessed body member, said alloy insert providing the lower portions of said injector and valve port bosses and being brazed to the upper portions thereof.

Claim 6

A cylinder head as claimed in claim 3 in which the insert is an alloy having a chromium content of 4-22 percent by weight, a nickel content of 0-60 percent by weight, a carbon content of 0.2-2.1 percent by weight, and the balance predominantly iron.

Claim 7

A cylinder head as claimed in claim 4 in which the nickel content is 40-60 percent.

Claim 8

A cylinder head as claimed in claim 3 in which the insert is an alloy having a composition by weight of:

Claim 9

A cylinder head as claimed in claim 3 in which the alloy has the approximate composition by weight:

Claim 10

A cylinder head as claimed in claim 3 which includes a plurality of fins extending upwardly from the upper surface of said insert at points between said valve port bosses and said injector boss.

Claim 11

A cylinder head as claimed in claim 3 in which said body member has a laterally extending flange at its upper end for engagement by hold-down means.

Claim 12

A cylinder head as claimed in claim 9 in which said flange is separately formed from said body member, said body member being of cast iron, and said flange being of cast steel and having a portion abutting the upper surface of said cast iron body member and being brazed thereto.

Claim 13

A cylinder head as claimed in claim 10 in which said flange is a ring having an internal step providing said abutting portion.

Claim 14

A cylinder head as claimed in claim 9 in which said body member and said flange comprise an integral steel casting.

Claim 15

A cYlindrical head as claimed in claim 3 in which the recess of said recessed body member is a stepped recess, said insert peripheral portion fitting within the step of said stepped recess, said lower portions of said injector and valve port bosses extending upwardly beyond the level of the upper surface of said peripheral portion.

Claim 16

A cylinder head for a large internal combustion engine comprising a body member adapted to provide a plurality of combustion surfaces at one surface thereof, a water jacket portion adjacent said combustion surfaces, said water jacket portion having both upper and lower walls, a plurality of apertured bosses extending through said water jacket portion and providing ports opening into each of said combustion surfaces, bolt holes located around the periphery of each of said combustion surfaces, said lower wall of said water jacket portion comprising a plurality of inserts of an iron alloy containing chromium having substantially the same coefficient of expansion as the material of said body member, the peripheral edges of each of said inserts being spaced inwardly from said bolt holes, said body member having recesses to accommodate each of said alloy inserts, and the lower surface of each insert providing a combustion surface for said cylinder head of said iron-chromium alloy material, the peripheral portion of each insert being brazed to the adjacent surface portion of said recessed body member, said alloy inserts providing the lower portions of said port bosses and being brazed to the upper portions thereof.

Claim 17

A cylinder head for a large internal combustion engine comprising a body member adapted to provide a plurality of combustion surfaces at one surface thereof, a water jacket portion adjacent said combustion surfaces, said water jacket portion having both upper and lower walls, a plurality of apertured bosses extending through said water jacket portion and providing ports opening into each of said combustion surfaces, bolt holes located around the periphery of each of said combustion surfaces, said lower wall of said water jacket portion comprising a plurality of inserts of an iron alloy containing chromium having substantially the same coefficient of expansion as the material of said body member, the peripheral edges of each of said inserts being spaced inwardly from said bolt holes, said body member having recesses to accommodate each of said alloy inserts, and the lower surface of each insert providing a combustion surface for said cylinder head of said iron-chromium alloy material, the peripheral portion of each insert being brazed to the adjacent surface portion of said recessed body member, said alloy inserts providing the lower portions of said port bosses and being brazed to the upper portions thereof.