( a ) problem: the axis deviation caused by vibration, shorten the mechanical seal life, at the same time noise.
Solution: use of polyimide carbon fiber composite impeller ring with the stainless steel pump shell ring; with our materials of throat bushing is used instead of the original graphite bush.
Results: reducing the amplitude of vibration, thereby prolonging the service life of sealing and bearing service life, enhances the pump free operation. A lot of pump in use is as a filler to packing, packing the main role is to prevent leakage, but also plays the role of bearing, stability axis. At present a lot of pump has been packing to mechanical seal, along with the mechanical seal transformation, bearing impact without, and axis deviation ( high vibration and impact) has become a problem.
Polyimide carbon fiber composite material to improve pump, successfully resolved the problem of customers, mainly in the following points:
1) polyimide carbon fiber composite material is a metal wear, occlusal materials. This makes the operation space narrowing ( only API metal material gap half), a smaller gap bushing can be stable axis, a smaller gap mouth ring may further restrict leakage and leakage rate.
2) polyimide carbon fiber composite material is a kind of high strength, high performance thermoplastic materials. It is easy for injection, able to absorb vibration and impact, while in the substituted metal can cause vibration and shaft wear.
Parts: equipped with movable seal sleeve and the Teflon bearing
( two) problems: support bearing severe wear. The factory tried many different materials such as carbon, graphite, with a filler material Teflon, trying to find a suitable to solve the wear and axis deviation problem, all material from 2 to 3 months on the scrapped. The PTFE material products due to wear and makes the shaft wear, greatly leak, causing mechanical seal failure.
Solution: use of polyimide carbon fiber composite material instead of using filler PTFE bearing.
Results: polyimide carbon fiber composite material supporting bearings installed, has been successfully operating for more than 13 months, after eighth months of use, stirrer center portion being removed temporarily to use other equipment, at that time, the staff of the stirrer bearing detection, found on each side of each inch of leakage of less than 0.005, the average failure interval time improve 300% to 400%.
( three) problems: this pump is a hard shell with stainless steel and stainless steel orifice ring and liner. Generally speaking, the gap of the pump dry transfer because of operation to reduce the amount of generated during inhalation, and some of the main stem turn often leads to premature pump damage, metal parts has also been a great damage. While these pumps mean time between failure and only six months.
Solution: use of polyimide carbon fiber composite material instead of stainless steel impeller ring and liner, reducing the gap of approximately 50% operation.
Results: using polyimide carbon fiber composite material modified pump has now been in use for over a year. Previously operation process in some bad situation often occurs, causing the gap of the stem, the pump can not work, but after a polyimide carbon fiber composite materials have caused the phenomenon of delayed update. In addition, the customer has issued a report : using polyimide carbon fiber composite material on its transformation, reduce operation gap, pump output flow has increased by 400gpm, but also on the other two multistage pumps were updated.
( four) problems: severe vibration, low pump efficiency
Solution: use of polyimide carbon fiber composite material for pump shell ring and liner. Running clearance by the API standard is reduced to 0.0015 inches in diameter per inch.
Results: the starting vibration 0.600 inches / second, the improved vibration 0.094 inches / second, enhance the efficiency of 5%.
Vibration vibration is reduced due to the following reasons:
1) a recirculation flow and its effect on reducing rotor instability;
2) reduced gap, reducing shaft running;
3) natural thermoplastic materials are easy to injection molding properties, absorption of vibration or shock.
Efficiency : improve the efficiency is reduced because the pump shell and the impeller ring gap. In the pump clearance would in turn reduce internal recirculation here.
Reliability: this pump has been working for more than four years, the refinery also has? Polyimide carbon fiber composite material used in more than 10 pumps.
Polyimide carbon fiber composite material anti abrasive material advantages characteristics and application:
A has good abrasion resistance. In the condition of grinding particles than rubber, bronze, carbon and graphite material.
B. Widely used in sewage pump, sea water pump (work environment is sand and other abrasive grain ) in the Bush, pipeline pump bearing and a wear ring.
C. Recommended only as a fixed component ( due to the material temperature limit ).
D. Compared to the other non-metallic materials, anti abrasive composite material has better chemical corrosion resistance.
E. Compared to the rubber bushing and other metal materials, polyimide carbon fiber composite material has a very low coefficient of friction.
