What are common preventive maintenance schedules and checklists for pumps?
Common preventive maintenance for pumps includes regular inspection for stability and balance, scheduled lubrication, and thorough evaluation of potential problems. Pumps receiving proper maintenance in this manner almost never experience a catastrophic failure. Beyond a quick visual daily check, most preventive maintenance tasks are monthly with a few yearly tasks in order.
What are pumps?
A wide variety of pumps are available for a multitude of industries and applications. Most pumps are either dynamic or positive displacement pumps.
Dynamic pumps, also known as centrifugal pumps, use centrifugal force to develop required pressure. Radial flow pumps only use this force while mixed-flow partially uses this force. Axial flow pumps use a propelling action to create pressure.
A positive displacement pump uses an expanding and decreasing cavity to create a consistent flow at set revolutions per minute (rpm). They have either single or multiple rotors.
Pump Maintenance
Unfortunately, pumps are frequently neglected when it comes to preventive maintenance. To operate at peak efficiency, secure, align, and balance pumps upon installation. In practice, pumps are often placed in precarious locations or misaligned. In addition, regular lubrication is critical to efficient and smooth operation.
Although many companies may opt to replace parts or even pumps instead of maintaining them, this can be costly. Pumps often operate as an integral part of a larger system, putting these other components at risk for failure.
Preventive Maintenance Checklist for Pumps
When maintenance technicians sequence a pump, they should take a quick look at the equipment to make sure it appears to be operating properly.
Beyond the visual daily inspection, pumps need only monthly and annual maintenance. Lubrication, packing, alignment, and mounting should be checked every month. Resolve problems immediately for peak performance. Inspect bearings and the motor performance on an annual basis.
Kinematic Viscosity
You’ve probably heard of viscosity and viscous fluids before. A few examples that come to mind are honey, flavored syrups, and of course, lubricating oil. Kinematic viscosity aims to characterize how thick a certain fluid is. It is defined as a measure of the fluid's internal resistance to flow.
How is kinematic viscosity measured?
Kinematic viscosity is commonly expressed in centistokes (cSt), which is equivalent to one square millimeter per second (mm^2/s). This measure is determined by taking the time it takes a certain volume of fluid to flow through a measured distance. Since fluid viscosities vary with surrounding conditions, kinematic viscosity is reported with the temperature at which it was measured.
What is dynamic viscosity?
Dynamic viscosity, also known as absolute viscosity, also describes the resistance of a fluid to flow. It is understandably interchanged with kinematic viscosity, though these are very much distinct from each other. One clear difference with kinematic viscosity is the way dynamic viscosity is measured.
Dynamic viscosity measures the resistance of a fluid to an external force. This absolute viscosity is expressed in centipoises (cP) and is also reported with the temperature at which it was measured.
Dynamic viscosity can be related to kinematic viscosity by the fluid’s specific gravity (SG). Using cSt to express kinematic viscosity and cP for dynamic viscosity, the following equation can be used:
cSt = cP/SG
How does viscosity affect lubrication?
Lubrication, such as in bearings, works by forming a protective film between two moving surfaces. Depending on the range and speed of this motion, viscosity affects how this layer of lubricant forms over the material.
When checking lubrication on your preventive maintenance schedules, you might want to consider looking into dynamic viscosity.
Oil analysis programs use information such as oil viscosity to asses the condition of the oil and of the machine. Note that oils and lubricants can vary in performance as they are subjected to different working conditions.
More top checklists:
- Air compressors
- Air handlers
- Buildings Controls
- Chillers and cooling towers
- Fans
- Fire alarms and smoke detectors
- Motors
- Steam boilers
- Vehicles and fleets
- Also check out: How to Create a Preventive Maintenance Checklist
Want to keep reading?
What are the best ways to document my maintenance process to avoid siloed knowledge
The Optimum Preventive Maintenance Schedule: 7 Steps for Efficient and Effective Preventive Maintenance Planning and Scheduling
Maintenance Technician
4,000+ COMPANIES RELY ON ASSET OPERATIONS MANAGEMENT
Leading the Way to a Better Future for Maintenance and Reliability
Your asset and equipment data doesn't belong in a silo. UpKeep makes it simple to see where everything stands, all in one place. That means less guesswork and more time to focus on what matters.
![[Review Badge] GetApp CMMS 2022 (Dark)](https://www.datocms-assets.com/38028/1673900459-get-app-logo-dark.png?auto=compress&fm=webp&w=347){kind=logo}
![[Review Badge] Gartner Peer Insights (Dark)](https://www.datocms-assets.com/38028/1673900494-gartner-logo-dark.png?auto=compress&fm=webp&w=336){kind=logo}
What is viscosity index? How can we incorporate viscosity index in preventive maintenance checklists?
Viscosity index is a measure of the change of viscosity with temperature. It is arbitrary, unitless and is generally used to characterize the viscosity-temperature behavior of lubricating oils. Finally, the viscosity index is best to use when you need to figure out what lubricant to use in any given piece of machinery that needs lubricating.
Adding viscosity index to a preventive maintenance checklist
As with most things in maintenance, the viscosity index has much more behind it than the simple definition. When creating a preventive maintenance checklist, you want to understand how the viscosity index works to ensure that your machinery is well-lubricated.
The precise definition is that the viscosity index (VI) measures the change in viscosity between 40C and 100C. The less the viscosity changes over that range, the higher the VI.
This means that temperature is an extremely important factor in calculating the viscosity index. If you do not have the starting temperature of the oil lubricant, you cannot calculate this index. In general, the fewer changes in temperature, the better. This is because when the temperature doesn’t change, the oil lubricant is stable.
The more the temperature changes, the more chance there is that the oil lubricant is not stable and is not effective in the applications you wanted to use it in.
The more the temperature changes, the more chance there is that the oil viscosity changes and is not effective in the applications you wanted to use it in. Therefore, it's extremely important to understand the temperature range under which your lubricant will be operating in.
Why is it useful when you need lubricant?
Simply put, the capacity index gives you a checklist of temperatures that your lubricant needs to be at in order to be effective. This is particularly important in machinery maintenance where lubrication is part of day-to-day life.
What the viscosity index is used for in maintenance
The viscosity index is used in almost all types of maintenance tasks that require some type of oil lubricant. The correct kind keeps everything running smoothly and properly as it’s designed to do. The wrong kind of lubricant or the wrong temperature of lubricant can create an array of failure consequences which ripple out across many different things.