Yhb main oil pump bearings and seals are not resistant to wear and high temperature solutions

Yhb main oil pump bearings and seals are not resistant to wear and high temperature solutions (1) problems: shaft deviation causes high vibration, shortens stainless steel "target=_blank> stainless steel pump casing ring; throat liner with our material Replace the original graphite bushing.
The result: reduced vibration amplitude, which extends seal life and bearing life and enhances pump free operation. Many pumps use packing as a filler in their use. The main function of the packing is to prevent leakage, but it also acts as a bearing to stabilize the shaft. At present, many pumps have changed the packing to mechanical seals. With the change of mechanical seals, the impact of Botaibang bearings has disappeared, and shaft deviation (high vibration and related effects) has become a problem.
The yhb main oil pump uses a polyimide carbon fiber composite material to improve the pump and successfully solves the customer's problems. There are two main points:
1) Polyimide carbon fiber composite is a metal-free, non-biting material. This reduces the running clearance (only half of the gap between the metal gaps specified by the API), the smaller gap bushing stabilizes the shaft, and the smaller gap ring further limits leakage and leakage rates.
2) Polyimide carbon fiber composite is a high strength, high performance thermoplastic material. It is easy to inject and absorbs vibrations and shocks, while the metal being replaced can cause vibration and shaft wear.
Parts: With removable seal bushings and bearings (2) problems: The support bearings are subject to severe wear. The factory tried a lot of different materials such as carbon, graphite, and filler materials, trying to find a suitable solution to the problem of wear and shaft deviation. All materials were scrapped in 2 to 3 months. Among them, the PTFE product wears the shaft, causing great leakage, resulting in mechanical seal failure.
Solution: Replace the filler-filled PTFE bearing that was originally used with a polyimide carbon fiber composite.
RESULTS: After the polyimide carbon fiber composite support bearing was installed, it has been successfully operated for more than 13 months. At the 8th month after use, the center part of the agitator was removed and temporarily used for other equipment. At that time, the staff tested it. The agitator bearing found that the leakage per inch per inch was less than 0.005, and the average failure interval increased by 300% to 400%.
(C) There is a problem: the pump is made of stainless steel "target=_blank> stainless steel and stainless steel with a hard shell" target=_blank> stainless steel for the ring and bushing. In general, the dry running of the pump is due to the reduction of the suction volume during operation, and the main dry running conditions often lead to premature pump damage and metal parts are also greatly damaged. The average time between failures of these pumps is only six months.
Solution: Replace the stainless steel "target=_blank> stainless steel impeller ring and bushing with a polyimide carbon fiber composite material, reducing the operating clearance by approximately 50%.
RESULTS: Pumps modified with polyimide carbon fiber composites for the yhb main oil pump have been in use for more than a year now. Some unfavorable conditions often occur during the previous operation, causing intermittent dry rotation, which makes the pump inoperable, but this phenomenon has been delayed by the renewal of polyimide carbon fiber composites. In addition, the customer also issued a report: by using polyimide carbon fiber composite material to transform it, reducing the operating gap, the pump output flow has increased by 400gpm, and the other two multi-stage pumps have also been updated.
(4) Problems occur: severe vibration, low pump efficiency Solution: Polyimide carbon fiber composite material is used as the pump casing ring and bushing. The running clearance was reduced from the API standard to 0.0015 inches per inch of turning diameter.
Results: The initial vibration was 0.600 inches/second, the improved vibration was 0.094 inches/second, and the efficiency was increased by 5%.
Vibration: The reason for the vibration reduction is as follows:
1) Recirculation flow and its reduced instability to the rotor;
2) The clearance is reduced and the running of the shaft is reduced;
3) Natural thermoplastic materials have easy injection molding properties and absorb shock or impact.
Efficiency: The efficiency gain is due to the reduced clearance between the pump casing and the impeller ring. The gap here in the pump will in turn reduce internal recirculation.
Reliability: This pump has been working continuously for more than four years, and the refinery has already been? Polyimide carbon fiber composites are used on more than ten pumps.
Advantages and applications of polyimide carbon fiber composite anti-abrasive materials:
a. Excellent wear resistance. It is superior to rubber, bronze, carbon graphite and other materials in the case of abrasive particles.
b. Recommended only as a fixed part (due to temperature limits of the material).
c. Anti-abrasive composites have better chemical resistance than other non-metallic materials.
d. Polyimide carbon fiber composite materials have a very low coefficient of friction compared to rubber bushings and other metallic materials.
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