Dynamic seal

Abstract

A dynamic seal has a surface adapted for dynamic sealing, at least the surface of the seal formed from an alloy having a composition, in weight percent, approximately: 0.22-0.26% C; 10.0-12.1% Ni; 1.40-3.10% Cr; 1.0-2.2% Mo; 12.0-16.0% Co; and balance Fe and impurities. A combustion seal of the above construction is also described. The combustion seal may be in the form of at least one of a piston ring for a reciprocating piston and an apex seal for a rotary piston.

1 . An apex seal for a rotary piston comprising a surface adapted for dynamic sealing contact, at least the surface formed from an alloy having a composition comprising, in weight %, approximately: 0.22-0.26% C; 10.0-12.1% Ni; 1.40-3.10% Cr; 1.0-2.2% Mo; 12.0-16.0% Co; and balance Fe and impurities.  
   
   
       2 . The seal of  claim 1 , wherein the seal is formed entirely of the alloy.  
   
   
       3 . The seal of  claim 1 , wherein the surface is provided with a finish resulting in a surface roughness of near 0-36 RMS.  
   
   
       4 . The seal of  claim 1 , comprising a substantially rectangular shaped strip.  
   
   
       5 . The seal of  claim 1 , comprising a separate corner piece.  
   
   
       6 . The seal of  claim 1 , comprising a cross-sectional width of about 2 mm.  
   
   
       7 . The seal of  claim 1  comprising a cross-sectional width of about 3 mm.  
   
   
       8 . The seal of  claim 1 , wherein the composition comprises, in weight %, approximately: 0.23% C; 11.1% Ni; 3.10% Cr; 1.2% Mo; 13.0% Co; and balance Fe and impurities.  
   
   
       9 . A method of improving combustion sealing, the method comprising: forming at least a surface of a seal adapted for dynamic sealing from an alloy having a composition comprising, in weight %, approximately: 0.22-0.26% C; 10.0-12.1% Ni; 1.40-3.10% Cr; 1.0-2.2% Mo; 12.0-16.0% Co; and balance Fe and impurities; and installing the seal at a location such that at least a portion of the seal is exposed to combustion.  
   
   
       10 . The method of  claim 9 , further comprising forming the seal entirely from the alloy.  
   
   
       11 . The method of  claim 9 , further comprising providing the surface with a finish resulting in a surface roughness of near 0-36 RMS.  
   
   
       12 . The method of  claim 9 , wherein the seal is formed as a substantially rectangular strip, and is installed at an apex of a rotary piston of a rotary combustion engine.  
   
   
       13 . The method of  claim 12 , wherein the seal is formed with a separate corner piece.  
   
   
       14 . The method of  claim 9 , wherein the composition comprises, in weight percent, approximately: 0.23% C; 11.1% Ni; 3.10% Cr; 1.2% Mo; 13.0% Co; and balance Fe and impurities.  
   
   
       15 . A dynamic seal comprising a surface adapted for dynamic sealing, at least the surface of the seal formed from an alloy having a composition comprising, in weight percent, approximately: 0.22-0.26% C; 10.0-12.1% Ni; 1.40-3.10% Cr; 1.0-2.2% Mo; 12.0-16.0% Co; and balance Fe and impurities.  
   
   
       16 . The seal of  claim 15 , wherein the seal is formed entirely of the alloy.  
   
   
       17 . The seal of  claim 15 , wherein the surface is provided with a surface finish resulting in a surface roughness of near 0-36 RMS.  
   
   
       18 . The seal of  claim 15 , wherein the seal comprises a combustion seal.  
   
   
       19 . The seal of  claim 18 , wherein the combustion seal comprises at least one of a piston ring for a reciprocating piston and an apex seal for a rotary piston.  
   
   
       20 . The seal of  claim 15 , wherein the composition comprises, in weight percent, approximately: 0.023% C; 11.1% Ni; 3.10% Cr; 1.2% Mo; 13.0% Co; and balance Fe and impurities.