Pump bearing seals are not resistant to wear, high temperature solutions

(A) problems: shaft deviation caused by high vibration, shorten the life of the mechanical seal, while producing noise. Solution: A stainless steel pump housing washer was made of a polyimide carbon fiber composite impeller. The throat bushing of our material was used to replace the original graphite bushing. The result: reduced vibration amplitude, which extends the seal life and bearing life, enhanced pump free operation. Many pumps in use are packing as a packing, packing the main role is to prevent leakage, but also play the role of bearings, shaft stability. At present, many pumps have changed the packing to a mechanical seal. As the mechanical seal changes, the bearings have no effect and the shaft deviation (high vibration and related influences) becomes a problem. With polyimide carbon fiber composite materials to improve the pump, successfully solve the customer's problems, mainly in the following two points: 1) polyimide carbon fiber composite material is a metal-free wear, non-occlusion of the material. This results in a smaller operating gap (only half of the metal gap specified by the API), a smaller gap bushing stabilizes the shaft, and a smaller gap collar further limits leakage and leakage rate. 2) Polyimide carbon fiber composite is a kind of high strength, high performance thermoplastic material. It is easy to injection molded, able to absorb vibration and shock, while the metal being replaced can cause vibration and shaft wear. Parts: with removable seal sleeve and Teflon bearings (B) problems: support bearing severe wear and tear. The factory experimented with many different materials such as carbon, graphite and filled Teflon materials, trying to find a suitable solution to the problems of wear and shaft misalignment, all of which were scrapped in two to three months. PTFE-based products in which wear and tear caused the shaft wear, resulting in great leakage, resulting in mechanical seal failure. Solution: replace the original filled PTFE bearing with polyimide carbon fiber composite material. RESULTS: The polyimide carbon fiber composite bearing was installed and operated successfully for more than 13 months. At the 8th month after use, the central part of the mixer was removed for temporary use of other equipment. At that time, the staff detected Agitator bearings, found that leakage per inch per side is less than 0.005, mean time between failures increased by 300% to 400%. (C) problems: This pump is made of stainless steel and stainless steel with a hard shell for the mouth ring and bushing. In general, the dry pump gap is due to the reduction of the amount of inhalation during operation, and some of the main dry turn often lead to premature pump damage, metal parts are also greatly damaged. The average failure time of these pumps is only six months long. Solution: Replace the stainless steel impeller spigot and bushing with polyimide carbon fiber composite to reduce the operating gap by approximately 50%. Results: Pumps modified with polyimide-based carbon fiber composites have now been in use for more than a year. In the past, some bad conditions often appeared during operation, causing intermittent dry rotation, which made the pump unable to work. However, this phenomenon has been postponed by the polyimide-carbon fiber composite material renewal. In addition, the customer also reported that the use of polyimide-based carbon fiber composite material to transform it, reducing the operating gap, the pump output flow has increased 400gpm, but also to the other two multi-stage pump was updated. (D) problems: violent vibration, low pump efficiency Solution: polyimide carbon fiber composite materials for the pump shell mouth ring and bushing. The running clearance is reduced from the API standard to a diameter of 0.0015 inch per inch. Results: Initial vibration 0.600 inch / second, improved vibration 0.094 inch / second, efficiency 5%. Vibrations: Vibrations are reduced for the following reasons: 1) recirculation flow and its effect on rotor instability are diminished; 2) clearance is reduced and shaft running is reduced; 3) natural thermoplastic materials are easily injection molded and absorb vibration Or impact. Efficiency: The increased efficiency is due to the reduced clearance between the pump housing and the impeller ring. The gap here at the pump can reduce internal recirculation. Reliability: The pump has been working continuously for more than four years, and the refinery has also used polyimide-based carbon fiber composites in over a dozen pumps. Advantages of Polyimide Carbon Fiber Composites Anti-Abrasive Materials Features and Applications: a. Has excellent anti-wear properties. It is superior to rubber, bronze, carbon graphite and other materials in abrasive conditions. b. Widely used in sewage pump, seawater pump (working environment is sand and other abrasive particles) in the bush, pipeline pump bearings and bowl wear ring. c. Recommended only as a stationary part (due to material temperature limitations). d. Anti-abrasive composites have better chemical resistance than other non-metallic materials. e. Polyimide-carbon fiber composite materials have a very low coefficient of friction compared to rubber bushings and other metallic materials.