the maintenance program for Centrifugal Pump
Maintenance engineer responsible to develop a maintenance program to make sure that every rotating equipment can run and operate safely without any breakdown or emergency failure. The program consists of preventive task, predictive task or function test task.
A preventive task is a task to replace or renew an aged part with a new one to prevent any failure. Preventive maintenance is triggered by time, events, or meter readings. For example, changing lube oil every 6 months, changing the lube oil filter every 12 months, etc.
A predictive task is a task to measure equipment condition. Predictive maintenance is based on the actual condition of the equipment rather than on time or age factors. It is used to predict machine failures before they occur, and also gives company enough time to schedule a future service appointment in advance, For example, vibration measurement every 3 months for a centrifugal pump or wall thickness measurement for a tank or pressure vessel using NDT tools named UT. Function test is a task to prove or to make sure that any system is functioning properly. for example, a function test of High-level alarm and switch in a tank. if liquid level inside a tank increases at a certain condition, instrumentation will start a pump to run automatically.
Predictive maintenance task 1: Vibration
vibration technology is widely used around the world to predict the pump condition. An inspector takes vibration data on the pump body at many locations such as pump side (horizontal, vertical, axial), motor side (horizontal, vertical, axial) and gearbox. Based on this vibration data, inspector evaluate any anomaly like pump misalignment, pump bearing condition or motor bearing condition.
Predictive maintenance task 2: Lube oil analysis
Routine oil analysis is an effective way of gauging the condition of a lubricant and determining optimum change intervals — to get the most life out of the oil in use as well as provide maximum continuous protection of equipment. An inspector takes a lube oil sample from a pump to evaluate the condition in a laboratory. He collects samples when the lubricant is well-mixed and at normal operating temperature. Preferably, the equipment should run for at least 20 minutes prior to sampling to help ensure complete heating and circulation of the lubricant. some time inspector takes samples from a well-selected point, ideally downstream of components but before the fluid passes through any filters. Allow some of the initial fluid to drain before collecting the sample, as the first fluid out may contain greater concentrations of water or sludge than the oil in the system contains overall. Based on lube oil report, the inspector will evaluate wear, contamination, and chemistry of lube oil.
Predictive maintenance task 3: Infrared thermograph
An inspector takes thermograph on pump bearing, gearbox, motor bearing, and electrical control panel. Based on thermograph result, the inspector will find any hot spot that indicated a failure. the result of infrared thermograph can support vibration analysis. for example, if a pump has a bearing failure, this anomaly will be found by high vibration data and hot spot in thermograph.