Close fit cylinder and plunger

Abstract

A pump that includes a cylinder housing having a through bore. A cylinder liner is disposed substantially within the through bore and includes a substantially uniform aperture having a first diameter. A plunger includes an engagement portion having a second diameter smaller than the first diameter. The first diameter and the second diameter are sized to define a first diametrical clearance that is less than about 0.1 percent of the second diameter.

1 . A pump comprising: 
 a cylinder housing including a through bore;    a cylinder liner disposed substantially within the through bore and including a substantially uniform aperture having a first diameter;    a plunger including an engagement portion having a second diameter smaller than the first diameter, the first diameter and the second diameter sized to define a first diametrical clearance that is less than about 0.1 percent of the second diameter.    
   
   
       2 . The pump of  claim 1 , wherein the plunger includes a clearance portion having a third diameter.  
   
   
       3 . The pump of  claim 2 , wherein the first diameter and the third diameter are sized to define a second diametrical clearance that is between about 5 and 20 times the first diametrical clearance.  
   
   
       4 . The pump of  claim 1 , wherein the first diametrical clearance is about 0.06 percent of the second diameter.  
   
   
       5 . The pump of  claim 1 , wherein the through bore defines a bore diameter and the cylinder liner defines an outside diameter that is larger than the bore diameter to define an interference fit between the cylinder housing and the cylinder liner.  
   
   
       6 . The pump of  claim 1 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about 2.5 times the second diameter.  
   
   
       7 . The pump of  claim 1 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about four times the second diameter.  
   
   
       8 . The pump of  claim 1 , wherein at least one of the cylinder liner and the plunger are manufactured from a ceramic material.  
   
   
       9 . The pump of  claim 1 , wherein the cylinder liner includes an alumina oxide ceramic.  
   
   
       10 . The pump of  claim 1 , wherein the cylinder liner includes a zirconia toughened alumina ceramic material.  
   
   
       11 . The pump of  claim 1 , wherein the plunger includes a zirconia toughened alumina ceramic material.  
   
   
       12 . The pump of  claim 1 , wherein the plunger is adapted to reciprocate within the cylinder liner to raise the pressure of a fluid to a pressure greater than about 10,000 pounds per square inch.  
   
   
       13 . The pump of  claim 1 , wherein the plunger cooperates with the cylinder liner to define the sole seal therebetween.  
   
   
       14 . A pump comprising: 
 a cylinder housing including a through bore;    a cylinder liner disposed substantially within the through bore and including a substantially uniform aperture having a first diameter;    an elongated plunger including an engagement portion having a second diameter and a clearance portion having a third diameter, the first diameter and the second diameter sized to define a first diametrical clearance and the first diameter and the third diameter sized to define a second diametrical clearance that is between about 5 and 20 times the first diametrical clearance.    
   
   
       15 . The pump of  claim 14 , wherein the second diameter is less than about 1.5 inches.  
   
   
       16 . The pump if  claim 14 , wherein the first diametrical clearance is less than about 0.1 percent of the second diameter.  
   
   
       17 . The pump of  claim 14 , wherein the first diametrical clearance is about 0.06 percent of the second diameter.  
   
   
       18 . The pump of  claim 14 , wherein the through bore defines a bore diameter and the cylinder liner defines an outside diameter that is larger than the bore diameter to define an interference fit between the cylinder housing and the cylinder liner.  
   
   
       19 . The pump of  claim 14 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about 2.5 times the second diameter.  
   
   
       20 . The pump of  claim 14 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about four times the second diameter.  
   
   
       21 . The pump of  claim 14 , wherein at least one of the cylinder liner and the plunger are manufactured from a ceramic material.  
   
   
       22 . The pump of  claim 14 , wherein the cylinder liner includes an aluminum oxide ceramic.  
   
   
       23 . The pump of  claim 14 , wherein the cylinder liner includes a zirconia toughened alumina ceramic material.  
   
   
       24 . The pump of  claim 14 , wherein the plunger includes a zirconia toughened alumina ceramic material.  
   
   
       25 . The pump of  claim 14 , wherein the plunger is adapted to reciprocate within the cylinder liner to raise the pressure of a fluid to a pressure greater than about 10,000 pounds per square inch.  
   
   
       26 . A pump comprising: 
 a plurality of pumping elements, each pumping element including: 
 a cylinder housing including a through bore;  
 a cylinder liner disposed substantially within the through bore and including a substantially uniform aperture having a first diameter; and  
 an elongated plunger including a drive end, an engagement portion opposite the drive end and having a second diameter, and a clearance portion between the drive end and the engagement portion and having a third diameter, the first diameter and the second diameter sized to define a first diametrical clearance and the first diameter and the third diameter sized to define a second diametrical clearance that is between about 5 and 20 times the first diametrical clearance; and  
   a drive member coupled to each drive end and operable to move each elongated plunger in a reciprocating fashion.    
   
   
       27 . The pump of  claim 26 , wherein the second diameter is less than about 1.5 inches.  
   
   
       28 . The pump if  claim 26 , wherein the first diametrical clearance is less than about 0.1 percent of the second diameter.  
   
   
       29 . The pump of  claim 26 , wherein the first diametrical clearance is about 0.06 percent of the second diameter.  
   
   
       30 . The pump of  claim 26 , wherein the through bore defines a bore diameter and the cylinder liner defines an outside diameter that is larger than the bore diameter to define an interference fit between the cylinder housing and the cylinder liner.  
   
   
       31 . The pump of  claim 26 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about four times the second diameter.  
   
   
       32 . The pump of  claim 26 , wherein the engagement portion extends along a long axis of the plunger for a length that is at least about 2.5 times the second diameter.  
   
   
       33 . The pump of  claim 26 , wherein at least one of the cylinder liner and the plunger are manufactured from a ceramic material.  
   
   
       34 . The pump of  claim 26 , wherein the cylinder liner includes an aluminum oxide ceramic.  
   
   
       35 . The pump of  claim 26 , wherein the cylinder liner includes a zirconia toughened alumina ceramic material.  
   
   
       36 . The pump of  claim 26 , wherein the plunger includes a zirconia toughened alumina ceramic material.  
   
   
       37 . The pump of  claim 26 , wherein the plunger is adapted to reciprocate within the cylinder liner to raise the pressure of a fluid to a pressure greater than about 10,000 pounds per square inch.  
   
   
       38 . The pump of  claim 26 , wherein the plurality of pumping units includes exactly one of three and five pumping units.  
   
   
       39 . The pump of  claim 26 , wherein the drive member includes a swash plate that is rotatable about a drive axis to sequentially reciprocate each plunger of the plurality of pumping units.  
   
   
       40 . The pump of  claim 26 , wherein the drive member includes a crankshaft that is rotatable about a drive axis to sequentially reciprocate each plunger of the plurality of pumping units.