Abstract:
A tool, method and apparatus to refurbish a valve seat having a compound geometry, such as a valve seat in a valve body for a common rail injector is disclosed. The tool includes a body with a head portion having substantially the same geometry as the valve seat to be refurbished, the tool further including a radiused portion between two angles of the valve seat to provide a chamfered surface on the valve seat to be refurbished. The method includes lapping the valve seat with the tool in and X, Y and Z axis to refurbish the valve seat in a single operation without substantially altering the geometry of the valve, and the apparatus includes slide moveable in an X and Y axis, and a fixture mounted on a preloaded biased base so movement in the Z axis is controllable.

Description:
TECHNICAL FIELD 
     In a common rail injector, the high pressure valve seat is used to control injector firing. When the magnetic energizer energizes, the armature lifts and a ball lifts from its seat. High pressure fuel (up to 2000 bar) spills out of the control chamber at elevated velocities between the ball and the valve seat. The lift of the ball is only in the order of about 50 microns, and this creates extreme fuel velocities, which make the area prone to cavitation. To address this, manufacturers have provided a small relief angle called a diffuser below the valve seat to help smooth the fluid flow past the ball/valve seat while the injector is firing. 
     It has been a challenge in remanufacturing the valve seat on a common rail injector to provide for consistent stock removal between the valve seat and the diffuser. Typical approaches had been lapping the valve seat, which only serves to reduce the effective diffuser diameter, which in turns increases the rate of cavitation. Lapping the valve seat and the diffuser separately presents extreme challenges in maintaining the diffuser diameter within acceptable tolerances. 
     There is a need for a tool, a process and an apparatus to lap the valve seat and maintain the diffuser diameter within acceptable tolerances in refurbishment of common rail fuel injectors. 
     SUMMARY 
     In one embodiment, the disclosure relates to a lapping tool to refurbish a ball check valve seat having compound geometric profile. The tool includes a body having a length and a width wherein the length may be greater than the width. The body so defined has a first end and a second end in opposed relation to each other. The first end is insertable into a unit for lapping tool motion in an X axis, a Y axis and a Z axis. The second end terminates in a head portion. The head portion may be equipped with an abrasive surface and has a compound geometric profile substantially the same as the compound geometric profile of said valve seat and also includes a radiused portion at the intersection of the compound geometric profile to create a chamfered surface. The tool is rotated at various speeds to facilitate refurbishing of the valve seat in a single action. 
     In another embodiment, the disclosure relates to a lapping tool to refurbish a ball check valve seat having a valve seat angle and a diffuser angle. The tool includes a body having a length greater than a width and opposed first and second ends. The first end is configured to be insertable in a lapping unit for motion of the tool in an X axis, a Y axis and a Z axis. The second end is equipped with a head portion having an abrasive surface. The head portion is configured to have a head valve seat angle and a head diffuser angle separated by a radiused portion. The head portion valve seat angle is of substantially the same angle as the valve seat angle, and the head portion diffuser portion angle is of substantially same angle as said valve seat diffuser angle. The head radiused portion forms a chamfered intersection between said valve seat angle and said valve seat diffuser angle to maintain the diameter of the refurbished diffuser. 
     In another embodiment, the disclosure relates to methods to refurbish a ball check valve having a valve seat portion with a first angle and a diffuser having a second angle, said first angle intersecting said second angle. One such method may include mounting a ball check valve; moving a lapping tool into engagement with the check valve an X axis, a Y axis and a Z axis; the lapping tool having a body with a length greater than a width; and opposed first and second ends; the first end being insertable in a lapping unit for motion of the tool in an X axis, a Y axis and a Z axis, and the second end equipped with a head portion having an abrasive surface. The head portion may have a valve seat angle and a diffuser angle separated by a radiused portion; the head portion valve seat angle of substantially the same angle as the valve seat angle, and said head portion diffuser portion angle of substantially same angle as said valve seat diffuser angle; and said head radiused portion forming a radiused intersection between said valve seat angle and said valve seat diffuser angle; the motion said lap tool in an X axis, a Y axis and a Z axis to remove cavitation from said valve seat and said diffuser portion and create a chamfered portion in at the intersection of said valve seat angle and said diffuser angle in a single operation. 
     In another embodiment the disclosure related to an apparatus to refurbish a ball check valve in a single operation. The apparatus may be a computer numerically controlled machining center, including a fixture configured to accept a ball check valve. The fixture is mountable in an precision slide machining apparatus for movement of the fixture in an X axis and a Y axis, and the fixture is supported by a preloaded biaser, such as, for example a spring, to control movement of the fixture in a Z axis. The apparatus may also include a rotary power unit suitable to rotate a lapping tool at various speeds. The lapping tool may be equipped with a body having a length greater than a width and opposed first and second ends. The first end is insertable in a lapping unit for motion of the tool in an X axis, a Y axis and a Z axis, and the second end is equipped with a head portion having an abrasive surface. The head portion has a valve seat angle and a diffuser angle separated by a radiused portion. The head portion valve seat angle of substantially the same angle as the valve seat angle, and the head portion diffuser portion angle of substantially same angle as said valve seat diffuser angle. The head portion also includes a radiused portion forming a chamfered intersection between said head portion valve seat angle and said head portion valve seat diffuser angle. 
     These and other aspects of the disclosure will be apparent upon a reading of the specification and consideration of the drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic representation of a common rail injector with a ball check valve; 
         FIG. 2  A is a detailed view of the ball check valve in the common rail injector of  FIG. 1 ; 
         FIG. 2B  is a cut way side view of the ball check valve of  FIG. 2A , showing its construction; 
         FIG. 2C  is a detailed view of a section of the ball check valve of  FIG. 2A , showing the seat valve; 
         FIG. 2D  is a detailed view of a section of the ball check valve of  FIG. 2B  showing the diffuser, diffuser distance and diffuser angle; 
         FIG. 3A  is a side view of one embodiment of a lapping tool according to the disclosure; 
         FIG. 3B  is a detailed view of the head portion of the lapping tool of  FIG. 3A  showing its configuration; 
         FIG. 4  is a sectional representation of one apparatus according to the disclosure; 
         FIGS. 5 through 9  are photomicrographs showing the machined valve seat and diffuser surfaces after various test times to simulate actual use wear. 
     
    
    
     DETAILED DESCRIPTION 
     Turning now to the drawings wherein like numbers refer to like structures,  FIG. 1  is a representation of a common rail injector  10 . While there are many parts and assemblies that comprise the common rail injector, the description will be only to those portions of the common rail fuel injector that are relevant to the inventive concepts of the present application, inasmuch as common rail injectors are well known to those skilled in the art and need not be described in great detail here. 
     The common rail  10  has a body portion  12  upon which is situated a nozzle portion  14  at one end thereof, and a magnetic energizer  16  at the opposite end. The energizer is electronically connected to an Electronic Control Unit (ECU) and energized as per fueling instructions held in memory of the ECU to permit fuel to pass through the injector and out of the nozzle. In this regard, fuel is introduced under pressure through intake fuel passage  18 , where it encounters ball check valve  30  in valve body  20 . The ball check valve body has a valve seat surface  22 , and a bearing  24 . The bearing sits on a bearing seat and obstructs diffuser passage  34 . The valve body is composed at least partially of a magnetic material such that when the magnetic energizer is energized, it attracts the valve out of engagement of its seat, and pressurized fuel displaces the bearing, and fuel passes to the high pressure fuel passage  28 , lifts the needle  15  in the nozzle  14 , and causes fuel to be injected into the engine through apertures (not shown). 
     Turning now to  FIG. 2A , there is shown a detail of the valve seat body  20  briefly described in reference to  FIG. 1 . With greater reference to valve seat body  20 , magnetic energizer  16  is in close proximity to valve  30 . The valve body has a compound geometry, with a first surface being a valve seat at a first angle. The valve  30  sits atop a bearing  24 , that is seated atop a diffuser passage, and has a second angle surface. 
       FIG. 2B  is a cutaway side view of the valve body of  FIG. 2A , showing its construction. Specifically, the valve body  30  sits in a valve seat  22 , which has a compound geometric profile of a first inclined surface at a first angle and a second incline surface at a second angle. A bearing  32  is provided in a diffuser passage. When the valve body is attracted by the magnetic energizer, highly pressurized fuel travels into the valve body along the valve seat and displaces the bearing to permit the flow of high pressure fuel into the high pressure fuel passage  34 . It should be understood that the bearing is displaced only a slight amount, on the order of about 50 microns, and the fuel is under such high pressure that, as the fuel travels along the valve seat and diffuser passage, cavitation occurs along those surfaces such that accuracy of the injection event is eventually compromised and refurbishing of the valve seat body is necessary to restore the common rail fuel injector to operating specification. 
     Turning now to  FIGS. 2C and 2D , there is shown a detail from  FIG. 2B  of the valve seat. Specifically, valve seat  22  has a surface with an angle Θ, at a first angle, and contiguous thereof is diffuser angle Φ of a second angle. The diffuser angle surrounds and intersects the diffuser passage  38  to define the ball or bearing seat  32 . It is the intersection of the diffuser angle and the ball seat that suffers most from cavitation as the fuel passes through the diffuser passage into the high pressure passage of the common rail injector. It is understood that the sharp contiguous angle intersection between the diffuser angle and the seat angle cause especially high pressure flow that contribute to cavitation. 
       FIG. 3B  is a detail view of the head portion  50  as seen in  FIG. 3A . the head has a tapered portion  52  and an angled work portion  54 , extending at a first angle, may be conical, parabolic, semi-spherical, or any other shape desired to refurbish the valve seat surface of the valve body. The work surface  60  is equipped with abrasive material  62 , to remove material from the valve seat of the valve body during a lapping motion. The abrasive may be at least one of diamond, cubic boron or silicon carbide, or any other suitable abrasive, and has a grit sufficient to refurbish the valve seat portion of the valve body. In one embodiment, the grit may be on the order of  30  microns. Concentric on the head at its distal end  59  is end diameter portion  58 , which extends a sufficient distance  56  to machine the diffuser, and the end diameter  58  is selected to be the same diameter as the diffuser intersection. The end diameter has a work surface  61  that extends in a second angle. The first angle portion of the head work surface is substantially the same angle as the first angle portion of the valve seat, and the second angle portion is substantially the same as the second angle surface of the diffuser. It is important to note that the intersection  63  between the surface  60  and the end diameter  58  is slightly radiused. Accordingly, it can be readily understood that the first angle portion and the second angle portion of the head do not intersect each other, but rather each one intersects the radiused portion  63 . 
     The abrasives may be deposited on the head portion by mixing the abrasive with a plating material, such as nickel, and overlaying the head portion. This plating will also form the radiused portion  63 . The radiused portion can also be formed by forming it when the head is formed, and then overlaying it with the abrasive, or in any other way that may be apparent to those skilled in the art. 
       FIG. 4  is a schematic representation of an apparatus  64  to refurbish valve seats according to one aspect of this disclosure. Specifically, the lapping tool  42  is fixed or inserted at its first end into rotary power unit  66  for variable speed rotation of the lapping tool. A floating assembly or collet or other suitable fixture  68  into which the valve seat body  20  is held is mounted in fixture  72 , which is floatably mounted on a preloaded biaser  78 , such as a coil spring, leaf springs, resilient material, a hydraulic or pneumatic cylinder arrangement, or any other arrangement is provided to govern the movement of the collet mounting assembly in the Z axis direction is provided, which in turn is mounted on a slide  67  for movement of the collet and fixture assembly in the X axis and the Y axis. When it is desired to refurbish a valve seat having a compound geometric profile (as described above) the valve seat body is mounted in the collet which is then placed in the fixture  72 . The lapping tool may be inserted in to rotary power unit  66  for rotary motion at various speed to provide lapping of the valve seat in a single operation. The rotary unit is lowered until the lapping tool contacts the valve seat surface. The rotary tool is rotated at a relatively high speed for stock removal of the valve seat body for a time sufficient to remove sufficient stock to remove traces of cavitation, and then at a low speed to improve valve seat roundness. Because the lapping tool head includes the radiused portion that finishes the diffuser diameter, the valve seat and the diffuser may be refurbished in a single action. The preloaded biaser prevents over machining in the Z axis, as it is preloaded and will only permit the correct force be applied in the Z axis, as it will bias away from the lapping tool if the tool is plunged too deeply into the valve seat body. The slide is adapted to provide movement of the fixture and collet in the X axis and the Y axis, to allow for lapping of the valve seat to ensure complete removal of stock that may have been affected by cavitation. Generally, the valve seat is subjected to stock removal at tool rotary speeds up to about 2000 RPM until cavitation is removed, and then subjected to valve seat rounding at tool rotary speed of up to about 150 RPM. All machining aspects described above, such as the lowering of the rotary unit to contact the valve seat, activation of the tool for lapping, and adjustment of tool speed, may be controlled by a Computer Numerically Controlled (CNC) machine center  79 . 
     The lapping tool, apparatus and process create a refurbished valve seat body that has a chamfered undercut at the ball seat diffuser of the valve body. The chamfered undercut portion is created by the tool head portion at the area where the valve seat surface portion of the tool head radiuses into the diffuser of the head tool portion. The creation of the chamfered portion reduces fuel flow forces and reduces cavitation due to fuel flow during injector use. In addition, the diffuser diameter is not changed because of the chamfer portion, and the injector can be restored to specification and remain in service for extended periods between refurbishment. 
     Table 1 shows that the refurbished injectors were tested for four points according to Original Equipment Manufacturer (OEM) specifications. The table contains data that is illustrative, but not limiting, of the concepts in this disclosure. Table 1 shows several test examples of valve seat bodies refurbished with one embodiment of the described lapping tool in one embodiment of the apparatus as described above. 
     
       
         
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
             
             
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Cycle 
                 2VolumeHE 
                   
                   
               
               
                 Sample 
                 Type 
                 Part Type 
                 Model 
                 Date 
                 Time 
                 Part No. 
                 PASS 
                 Time 
                 Emissions 
                 2SpillFlow 
                 2RailPress 
               
               
                   
               
             
          
           
               
                 After 512 Hours 
               
             
          
           
               
                 1 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:16 
                 A 647 070 
                 TRUE 
                 265 
                 19.2418 
                 12 
                 807 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:34 
                 A 647 070 
                 TRUE 
                 263 
                 19.4377 
                 9 
                 800 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.1959 
                 −3 
                 −7 
               
               
                 2 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:48 
                 A 647 070 
                 TRUE 
                 263 
                 19.079 
                 18 
                 807 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:28 
                 A 647 070 
                 FALSE 
                 262 
                 19.1645 
                 8.625 
                 797 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.0856 
                 −9.375 
                 −10 
               
               
                 3 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:11 
                 A 647 070 
                 TRUE 
                 263 
                 19.8474 
                 11.25 
                 793 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:50 
                 A 647 070 
                 FALSE 
                 263 
                 21.0375 
                 10.125 
                 795 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  1.1901 
                 −1.125 
                 2 
               
               
                 4 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:59 
                 A 647 070 
                 TRUE 
                 263 
                 19.8593 
                 9.75 
                 804 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:44 
                 A 647 070 
                 FALSE 
                 262 
                 20.7 
                 8.625 
                 794 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.8407 
                 −1.125 
                 −10 
               
               
                 5 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:27 
                 A 647 070 
                 TRUE 
                 263 
                 18.3416 
                 12 
                 795 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:39 
                 A 647 070 
                 TRUE 
                 263 
                 18.5956 
                 7.5 
                 800 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.254 
                 −4.5 
                 4 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 AVG 
                  0.51326 
                 −3.825 
                   
               
             
          
           
               
                   
                 Field Tolerance 
                  1.8 
               
               
                   
                 (+/−) 
               
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Cycle 
                 3VolumeHE 
                   
                   
               
               
                 Sample 
                 Type 
                 Part Type 
                 Model 
                 Date 
                 Time 
                 Part No. 
                 PASS 
                 Time 
                 Pilot 
                 3SpillFlow 
                 3RailPress 
               
               
                   
               
             
          
           
               
                 After 512 Hours 
               
             
          
           
               
                 1 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:16 
                 A 647 070 
                 TRUE 
                 265 
                 0.8754 
                 8.25 
                 796 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:34 
                 A 647 070 
                 TRUE 
                 263 
                 0.9944 
                 6 
                 792 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.119 
                 −2.25 
                 −4 
               
               
                 2 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:48 
                 A 647 070 
                 TRUE 
                 263 
                 1.2697 
                 15.75 
                 795 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:28 
                 A 647 070 
                 FALSE 
                 262 
                 1.8517 
                 7.125 
                 804 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.582 
                 8.625 
                 9 
               
               
                 3 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:11 
                 A 647 070 
                 TRUE 
                 263 
                 1.2374 
                 7.5 
                 800 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:50 
                 A 647 070 
                 FALSE 
                 263 
                 1.9547 
                 8.25 
                 802 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.7173 
                 0.75 
                 2 
               
               
                 4 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:59 
                 A 647 070 
                 TRUE 
                 263 
                 1.4629 
                 7.5 
                 797 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:44 
                 A 647 070 
                 FALSE 
                 262 
                 2.3531 
                 5.625 
                 798 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.8902 
                 −1.875 
                 1 
               
               
                 5 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:27 
                 A 647 070 
                 TRUE 
                 263 
                 1.0997 
                 9.75 
                 796 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:39 
                 A 647 070 
                 TRUE 
                 263 
                 1.3048 
                 6 
                 802 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.2051 
                 −3.75 
                 6 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 AVG 
                 0.50272 
                 3.15 
                   
               
             
          
           
               
                   
                 Field Tolerance 
                 1 
               
               
                   
                 (+/−) 
               
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Cycle 
                 4VolumeH 
                   
                   
               
               
                 Sample 
                 Type 
                 Part Type 
                 Model 
                 Date 
                 Time 
                 Part No. 
                 PASS 
                 Time 
                 Idle 
                 4SpillFlow 
                 4RailPress 
               
               
                   
               
             
          
           
               
                 After 512 Hours 
               
             
          
           
               
                 1 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:16 
                 A 647 070 
                 TRUE 
                 265 
                 4.5918 
                 4.8 
                 252 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:34 
                 A 647 070 
                 TRUE 
                 263 
                 5.45 
                 3.375 
                 249 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.8582 
                 −1.425 
                 −3 
               
               
                 2 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:48 
                 A 647 070 
                 TRUE 
                 263 
                 5.1475 
                 5.25 
                 251 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:28 
                 A 647 070 
                 FALSE 
                 262 
                 5.7999 
                 4.5 
                 251 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.6524 
                 −0.75 
                 0 
               
               
                 3 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:11 
                 A 647 070 
                 TRUE 
                 263 
                 5.47 
                 3.9375 
                 251 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:50 
                 A 647 070 
                 FALSE 
                 263 
                 5.9774 
                 3.9375 
                 250 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.5074 
                 0 
                 −1 
               
               
                 4 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:59 
                 A 647 070 
                 TRUE 
                 263 
                 5.7541 
                 4.6875 
                 253 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:44 
                 A 647 070 
                 FALSE 
                 262 
                 6.3754 
                 4.5 
                 250 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.6213 
                 −0.1875 
                 −3 
               
               
                 5 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:27 
                 A 647 070 
                 TRUE 
                 263 
                 4.4084 
                 4.5 
                 248 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:39 
                 A 647 070 
                 TRUE 
                 263 
                 5.2133 
                 3.75 
                 247 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 0.8049 
                 −0.75 
                 −1 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 AVG 
                 0.68884 
                 −0.6225 
                   
               
             
          
           
               
                   
                 Field Tolerance 
                 1.3 
               
               
                   
                 (+/−) 
               
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                   
                   
                   
                 Cycle 
                 5VolumeHE 
                 5SpillFlow 
                   
               
               
                 Sample 
                 Type 
                 Part Type 
                 Model 
                 Date 
                 Time 
                 Part No. 
                 PASS 
                 Time 
                 Full Load 
                 Spill Flow 
                 5RailPressure 
               
               
                   
               
             
          
           
               
                 After 512 Hours 
               
             
          
           
               
                 1 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:16 
                 A 647 070 
                 TRUE 
                 265 
                 57.5556 
                  31.75 
                 1594 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:34 
                 A 647 070 
                 TRUE 
                 263 
                 58.2463 
                  26.125 
                 1599 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.6907 
                  −5.625 
                 5 
               
               
                 2 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:48 
                 A 647 070 
                 TRUE 
                 263 
                 57.2882 
                  46 
                 1593 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:28 
                 A 647 070 
                 FALSE 
                 262 
                 57.506 
                  31 
                 1598 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.2578 
                 −15 
                 5 
               
               
                 3 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:11 
                 A 647 070 
                 TRUE 
                 263 
                 57.0978 
                  38.625 
                 1592 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:50 
                 A 647 070 
                 FALSE 
                 263 
                 57.7607 
                  36.875 
                 1598 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.06629 
                  −1.75 
                 6 
               
               
                 4 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 12:59 
                 A 647 070 
                 TRUE 
                 263 
                 58.5119 
                  32.25 
                 1596 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:44 
                 A 647 070 
                 FALSE 
                 262 
                 59.3291 
                  29.75 
                 1600 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.8172 
                  −2.5 
                 4 
               
               
                 5 
                 Product 
                 Injector 
                 1B 
                 May 4, 2010 
                 13:27 
                 A 647 070 
                 TRUE 
                 263 
                 57.2871 
                  36.5 
                 1593 
               
               
                   
                 Product 
                 Injector 
                 1B 
                 Aug. 11, 2010 
                  9:39 
                 A 647 070 
                 TRUE 
                 263 
                 58.0573 
                  28.625 
                 1595 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                  0.7702 
                  −7.875 
                 2 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 AVG 
                  0.063176 
                  −6.55 
                   
               
             
          
           
               
                   
                 Field 
                  2.5 
                  61 Max 
               
               
                   
                 Tolerance (+/−) 
               
               
                   
               
             
          
         
       
     
     Specifically,  FIG. 5  is a photomicrograph of sample 1, machined and tested as set forth in Table 1.  FIG. 5  shows light cavitation at the chamfer (radiused portion)/seat intersection. There was no progression of cavitation into the ball sealing area  57 . There is also exhibited a very consistent wear pattern with the core material. The ball sealing area shows normal wear after more than 512 hours of testing. 
       FIG. 6  is a photomicrograph of sample 2, machined and tested as test forth in Table 1. The figure shows heavier cavitation at the chamfer/seat intersection. However, there is no progression of cavitation into the ball sealing area  57 , and the core material shows very consistent wear pattern. In addition the ball sealing area  57  shows normal wear, after being machined and tested as set forth in Table 1. 
       FIG. 7  is a photomicrograph of Sample 3, machined and tested as set forth in Table 1. It can be seen that light cavitation occurred at the chamfer/seat intersection, with no progression into the ball sealing area. The core material also showed very consistent wear pattern, and the ball seating area  57  shows normal wear, after machining and testing as set forth in Table 1. 
       FIG. 8  is a photomicrograph of sample 4, machined and tested as set forth in Table 1. Again, there is no progression of cavitation into the ball sealing area  57 , and the core material shows very consistent wear pattern. The ball sealing area shows higher than average wear, but that wear is still consistent with the core material. 
       FIG. 9  is a photomicrograph of sample 5, machined and tested as set forth in Table 1. The sample shows a light cavitation at the chamfer/seat intersection, with no progression of cavitation into the ball sealing area. The core material shows a very consistent wear patter and the ball sealing area  57  shows normal wear. 
     Many modifications and variations of the invention as described are possible in light of the above teachings. In addition, the words used in the specification are of description, not limitation. Within the scope of the appended claims, the invention may be practiced other than as specifically described.