Ceramic liners and and ceramic plungers of drilling mud pumps
A) Ceramic liners and ceramic plungers features:
1,Corrosion-resistant,acid-proof alkali, heat-resistant, it can
work in the medium of the drilling mud or other corrosive liquid
etc.
2,High hardness, wear resistance,it can resist high pressure mud of
sharp or abrasive resistance of the solid particles grinding or
scour,such as rock debris,quartz sands,iron ores,scrap iron.
3,Evenly distributed structure for microstructure and smoothly
surface will improve the life of the piston.
4,Working pressure is high,more than 52 MPa (7500 PSI), to meet
drilling deep well, ultra-deep demand.
B) Ceramic liners and ceramic plungers material and performance index:
Ceramic liner and ceramic plungers take zirconia composite ceramic
formulations as the formula,after high pressure forming, sintering
and finishing process,a finished products is present out . The
composition ofzirconia: 5.4% yttria and 94.6%zirconia ,theaverage
particlesize less than 0.5 μm. As zirconia is reputed for its
highfracture toughness,it is thusused to improve the atigue
strength of the final product. But pure zirconia product tends to
be efflorescenceon the surface after long service at 100 to 250
℃damp environment. As a result,its abrasion resistance and
mechanical property declined greatly, no doubt,service life of the
product limited.The part of aluminum oxide comprises 99.9% aluminum
oxide,with average particle size less than 0.5μm.Aluminum oxide
hashigh hardnessand good abrasion performance,but its fracture
toughness is low.The product ofaluminum oxideis thus likely to
develop cracks. Mixture of zirconia and aluminum oxide through fine
process controlrealizes mutual supplementation of these two
substances, thusgetting round both efflorescencecommonly seen among
zirconia and low fracture toughness commonly seen among aluminum
oxide. Massive experiments show that the toughness is maximum when
80 --90% zirconia is added.We select super fine zirconia just to
get dense sintering result, and consequently fine finish of the
product.
C) Ceramic liners and ceramic plungers performance index:
| Item | Others | Jusheng Petroleum |
| Average grain (μm) | ≤ 7 | ≤ 3 |
| Rockwell hardness (HRA) | ≥ 89.5 | ≥ 91 |
| Bending strength (MPa) | ≥ 350 | ≥ 800 |
| Water absorbability (%) | ≤ 0.05 | ≤ 0.01 |
| Fracture toughness (MPa.M1/2) | ≥ 4 | ≥ 9 |
| Volume density (g/cm3) | ≥ 3.85 | ≥ 5.6 |
| Toughness of working surface | ≥ 0.40 μm when temp ≤ 350℃ | ≤ 0.25μm when temp ≤ 350℃ |
Wear resistance
(laboratory test) | 20 times more than that of
high chromium cast iron | 50 times more than that of
high chromium cast iron |
| Compression strength (MPa) | ≥ 3000 | ≥ 5000 |
| Thermal shock resistance (temperature crack) | ≥ 350℃ | ≥ 350℃ |
