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Pump Shaft Breakage: Case Studies and Solutions

By NTS

Pump shaft breakage is a common issue that can cause costly downtime and repairs in various industries. In this article, we will explore several case studies of pump shaft breakage and the solutions implemented to prevent future failures.

Case Study 1: Chemical Processing Plant

A chemical processing plant experienced repeated pump shaft breakages in their cooling water pumps. Investigation revealed that the pumps were not properly aligned with the motor and had excessive vibration due to the misalignment. This caused the pump shaft to fatigue and break over time. The problem was resolved by realigning the pumps and installing vibration monitoring equipment to detect any future misalignment or excessive vibration.

Case Study 2: Wastewater Treatment Plant

A wastewater treatment plant had issues with pump shaft breakage in their sludge pumps. The pumps were designed with a straight shaft and lacked a flexible coupling, causing excessive stress and vibration on the pump shaft. The problem was resolved by redesigning the pumps with a flexible coupling and a shorter shaft to reduce stress and vibration.

Case Study 3: Paper Mill

A paper mill experienced repeated pump shaft breakages in their pulp pumps. Investigation revealed that the pumps were handling abrasive pulp that was causing excessive wear on the pump components, including the pump shaft. The problem was resolved by replacing the damaged pump shafts with a more wear-resistant material and installing a vortex breaker in the suction line to reduce the impact of the abrasive pulp on the pump components.

Case Study 4: Power Plant

A power plant had issues with pump shaft breakage in their boiler feedwater pumps. Investigation revealed that the pumps were not properly lubricated, causing excessive heat and stress on the pump shaft. The problem was resolved by improving the lubrication system and installing temperature and vibration monitoring equipment to detect any issues with the lubrication and performance of the pumps.

Case Study 5: Oil and Gas Industry

An oil and gas company had repeated pump shaft breakages in their saltwater disposal pumps. Investigation revealed that the pumps were operating at a high flow rate and were experiencing cavitation, causing damage to the pump impeller and eventually leading to pump shaft breakage. The problem was resolved by reducing the flow rate and installing a cavitation eliminator to prevent future damage to the pump components.

Case Study 6: Mining Industry

A mining company had issues with pump shaft breakage in their tailings pumps. Investigation revealed that the pumps were not properly installed and were experiencing excessive vibration due to misalignment. This caused the pump shaft to fatigue and break over time. The problem was resolved by realigning the pumps and installing vibration monitoring equipment to detect any future misalignment or excessive vibration.

Case Study 7: Food Processing Plant

A food processing plant experienced repeated pump shaft breakages in their hot water circulation pumps. Investigation revealed that the pumps were operating at a high temperature and were experiencing thermal expansion and contraction, causing stress on the pump shaft. The problem was resolved by installing a flexible coupling and a longer shaft to accommodate the thermal expansion and contraction.

Case Study 8: Pharmaceutical Industry

A pharmaceutical company had issues with pump shaft breakage in their product transfer pumps. Investigation revealed that the pumps were not properly lubricated and were operating at a high temperature, causing excessive stress on the pump shaft. The problem was resolved by improving the lubrication system and installing temperature and vibration monitoring equipment to detect any issues with the lubrication and performance of the pumps.

Case Study 9: Water Treatment Plant

A water treatment plant experienced repeated pump shaft breakages in their high-pressure booster pumps. Investigation revealed that the pumps were operating at a high pressure and were experiencing excessive vibration, causing fatigue and eventual breakage of the pump shaft. The problem was resolved by installing a vibration eliminator and reducing the pressure of the system.

Case Study 10: Chemical Manufacturing Plant

A chemical manufacturing plant had issues with pump shaft breakage in their reactor feed pumps. Investigation revealed that the pumps were not properly aligned with the motor and were experiencing excessive vibration, causing fatigue and eventual breakage of the pump shaft. The problem was resolved by realigning the pumps and installing vibration monitoring equipment to detect any future misalignment or excessive vibration.

In each of these cases, the pump shaft breakage was caused by different factors, ranging from misalignment and excessive vibration to wear and lack of lubrication. However, in each case, the problem was identified and resolved by implementing appropriate design changes, maintenance procedures, and monitoring equipment to prevent future pump shaft breakage.

To prevent pump shaft breakage, it is important to properly design, install, and maintain pump systems. This includes ensuring proper alignment, installing flexible couplings, monitoring vibration and temperature, and using appropriate materials for the pump components. Regular maintenance, including oil changes and inspections, can also help to detect any issues with the pump system and prevent pump shaft breakage.

In conclusion, pump shaft breakage can be a costly and disruptive problem in various industries. However, by identifying the root cause of the problem and implementing appropriate solutions, pump shaft breakage can be prevented, leading to improved reliability, reduced downtime, and cost savings for businesses.

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