Pre-hardened steel composition and machine parts made therewith

Abstract

A mud pump with components manufactured from high strength and toughness steel is disclosed. The mud pump includes a power end and a fluid end. The power end includes a motor, crankshaft rotationally engaged with the motor and a connecting rod rotationally engaged with the crank shaft. The fluid end inclues a piston, a cylinder, a drilling fluid module, a discharge manifold, and a strainer cross. At least one of the plunger, the drilling fluid module, the discharge manifold, and the strainer cross has the following composition in weight percent: 0.25 - 0.55% carbon, 0.70 -1.50% manganese, a maximum of 0.025% phosphorous, a maximum of 0.050% sulfur, a maximum of 0.80% silicon, 0.10 - 0.80% nickel, 1.40 - 2.20% chromium, 0.10 - 0.55% molybdenum, a maximum of 0.030% vanadium, a maximum of 0.35% copper, a maximum of 0.040% aluminum, a balance of iron, and incidental impurities.

What is claimed is: 
     
         1 - 5 . (canceled) 
     
     
         6 . A fabricated machine part manufactured from a steel composition having the following composition in percent by weight: 
       
         
           
                 
                 
               
                   C 
                   0.20 - 0.55%, 
                 
                   Mn 
                   0.70 - 1.50%, 
                 
                   P 
                   0.025% max., 
                 
                   S 
                   0.050% max., 
                 
                   Si 
                   0.80% max., 
                 
                   Ni 
                   0.10 - 0.80%, 
                 
                   Cr 
                   1.40 - 2.20%, 
                 
                   Mo 
                   0.10 - 0.55%, 
                 
                   V 
                   0.030% max., 
                 
                   Cu 
                   0.35% max., 
                 
                   Al 
                   0.040% max., 
                 
                   Fe . 
                   balance, and incidental impurities 
                 
             
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
       . 
     
     
         7 . The machine part of  claim 6 , wherein the steel composition comprises the following composition in percent by weight: 
       
         
           
                 
                 
               
                   C 
                   0.20 - 0.35%, 
                 
                   Mn 
                   1.20 - 1.45%, 
                 
                   P 
                   0.025% max., 
                 
                   S 
                   0.025% max., 
                 
                   Si 
                   0.15 - 0.40%, 
                 
                   Ni 
                   0.35 - 0.70%, 
                 
                   Cr 
                   1.70 - 2.05%, 
                 
                   Mo 
                   0.35 - 0.55%, 
                 
                   V 
                   0.030% max., 
                 
                   Cu 
                   0.35% max., 
                 
                   Al 
                   0.040% max., 
                 
                   Fe 
                   balance, and incidental impurities. 
                 
             
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
     
     
         8 . The machine part of  claim 6 , wherein the steel composition comprises the following composition in percent by weight: 
       
         
           
                 
                 
               
                   C 
                   0.30 - 0.35%, 
                 
                   Mn 
                   1.20 - 1.35%, 
                 
                   P 
                   0.010% max., 
                 
                   S 
                   0.010% max., 
                 
                   Si 
                   0.20 - 0.35%, 
                 
                   Ni 
                   0.55 - 0.65%, 
                 
                   Cr 
                   1.75 - 2.00%, 
                 
                   Mo 
                   0.40 - 0.50%, 
                 
                   V 
                   0.010% max., 
                 
                   Cu 
                   0.20% max., 
                 
                   Al 
                   0.025% max., 
                 
                   Fe 
                   balance, and incidental impurities. 
                 
             
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
     
     
         9 . The machine part of  claim 6 , wherein a fabricated machine part made of the steel composition is prepared from a melt of steel prepared in an electric arc furnace by:
 a. melting the bulk of the steel composition containing the majority of the alloy ingredients to produce a steel melt suitable for tapping into a receptacle,   b. thereafter tapping, heating, alloying, and refining the heat to bring the heat to its final composition,   c. vacuum degassing, teeming and casting the heat by bottom pouring practices to form an ingot,   d. hot working the ingot to form a fabricated machine part, and   e. thereafter heat treating the fabricated machine part by water quenching and tempering to form a final hot work product.   
     
     
         10 . The machine part of  claim 9 , wherein the final hot work product is subsequently subjected to:
 austenitizing at a temperature of between 800° and 950° C.,   quenching in water, and   tempering at a temperature of between 500° and 700° C. to form a microstructure consisting mostly of martensite and bainite or a mixture of martensite, bainite and perlite which will be deeper than ¼ of the thickness of the block.   
     
     
         11 . The machine part of  claim 6 , wherein the machine part is a fluid module. 
     
     
         12 . The machine part of  claim 6 , wherein the machine part is a discharge manifold. 
     
     
         13 . The machine part of  claim 6 , wherein the machine part is a strainer cross. 
     
     
         14 . The machine part of  claim 6 , wherein the machine part is a component of oil field exploration machinery. 
     
     
         15 . The machine part of  claim 6 , wherein the machine part is a component of a mud pump. 
     
     
         16 - 20 . (canceled) 
     
     
         21 . The machine part of  claim 10 , wherein the machine part is a fluid module. 
     
     
         22 . The machine part of  claim 10 , wherein the machine part is a discharge manifold. 
     
     
         23 . The machine part of  claim 10 , wherein the machine part is a strainer cross. 
     
     
         24 . The machine part of  claim 10 , wherein the machine part is a component of oil field exploration machinery. 
     
     
         25 . The machine part of  claim 10 , wherein the machine part is a component of a mud pump. 
     
     
         26 . The machine part of  claim 6 , wherein the machine part is an adapter spool. 
     
     
         27 . The machine part of  claim 10 , wherein the machine part is an adapter spool. 
     
     
         28 . The machine part of  claim 6 , wherein the machine part is a discharge and suction module. 
     
     
         29 . The machine part of  claim 10 , wherein the machine part is a discharge and suction module. 
     
     
         30 . The machine part of  claim 7 , wherein a fabricated machine part made of the steel composition is prepared from a melt of steel prepared in an electric arc furnace by:
 a. melting the bulk of the steel composition containing the majority of the alloy ingredients to produce a steel melt suitable for tapping into a receptacle,   b. thereafter tapping, heating, alloying, and refining the heat to bring the heat to its final composition,   c. vacuum degassing, teeming and casting the heat by bottom pouring practices to form an ingot,   d. hot working the ingot to form a fabricated machine part, and   e. thereafter heat treating the fabricated machine part by water quenching and tempering to form a final hot work product, wherein the final hot work product is subsequently subjected to:
 austenitizing at a temperature of between 800° and 950° C., 
 quenching in water, and 
 tempering at a temperature of between 500° and 700° C. to form a microstructure consisting mostly of martensite and bainite or a mixture of martensite, bainite and perlite which will be deeper than ¼ of the thickness of the block.