By Pablo Martinez-Moore, North Ridge Pumps Ltd.
1. Maintain a Schedule
Maintenance is inevitable on any pump, but sticking to a concrete schedule can improve efficiency and reduce maintenance costs and times. Often, insufficient lubrication or too much lubrication can lead to bearing failure by causing a leak.
If a seal leak remains undetected, fluid will leak from the pump casing into bearings. If this is left unresolved, it could lead to detrimental pump failure, or the need for replacement. A maintenance schedule including a breakdown of daily, weekly, monthly, annually, and so forth, will assist in keeping a consistent time frame for maintenance. Daily tasks, such as checking temperatures, to weekly tasks such as checking differential pressure or excess noise, are all part of a schedule that must be followed.
2. Check Performance
Over time a pump’s performance may deteriorate or the conditions it faces change. A manual check and inspection can assist in determining whether a pump is meeting its needs early on. A pump’s performance should always be checked to ensure it is not cavitating. A doubling in wear ring clearances can mean NPSH increases by 50%. If there are imperfections in the pump’s performance or design that go unnoticed, it could lead to replacement sooner than expected.
3. Drop In Replacements
If deterioration does occur, it is important to identify and replace parts right away. Pump inserts or bare shaft pumps ensure replacement pumps can be placed into the process with minimal disruption or downtime ensuring process uptime.
4. Specifying Design
Some designs of pumps have far more spare parts than other models. Maintenance can become puzzling trying to refit all parts, along with time pressure constraints, meaning mistakes are likely.
Maintenance can often take longer than is required on inferior designs, which is not always apparent at the time of purchase of a pump. The time that is taken to service some pumps can be reduced by up 50% when specified correctly.
5. Specifying Type
Different applications and fluids will require different types of pumps. Not all pumps are created equally. Some designs are better suited for abrasive slurries, can accommodate dry running, or are better suited for 24/7 operation. Changes in pump types can mean energy savings of between 20-30% with an equivalent reduction in spares costs. By re-evaluating the current application against the pump type in use, one may find that a different pump is better suited.
6. Specifying Size
Quite often a pump is installed in an application based on cost rather than factoring in full application details. If this is the case, sometimes the design or type does not need to be changed, but rather an increase in size is necessary. Units may be operating too fast meaning spares are being replaced frequently. Increasing the pump size, and running it slower, is often a way of ensuring longevity by reducing wear.
7. Pump Monitoring
Automation can help reduce maintenance needs, and remotely monitoring a pump can mean early detection of a reduction in flow, pressure, vibration, excess temperature, or increase in power consumption. This enables condition-based maintenance to be undertaken before failure and requirements become urgent. It also means pumps are dismantled when required rather than unnecessarily.
Did You Know?
Automating a pump can reduce reliance on manual maintenance and personnel required. Automating can also help improve dispensing accuracy, prevent loss of product, prevent pump from running dry or being damaged against a closed valve, and reduce labor costs. Some of the pump applications that are typically benefited from being automated are batching and dispensing, heating and cooling, dosing and metering, dewatering, multiphase pumping, pressure boosting, recirculation, transfer, and unloading.
Here are 17 ways to automate a pump:
1. Amp Draw: The current drawn can be set within a control panel to certain limits, which would detect when a pump is dry running or cavitating. This helps limit damage if a pump is unattended.
2. Bypass Valve: A bypass valve on the pump and discharge pipework will protect the pump from a nozzle being closed or a discharge valve closing, to prevent damage.
3. Dry Run Capability: Pumps which are specified with dry run capability means it can be left unattended, and fluid with a high amount of dry content will not damage the pump.
4. Dry Run Protection: Sensors can be used to check for amp draw, power absorbed, and measure unlet pressure, to protect the pump from dry running.
5. End of Stroke Sensor: This can provide details on the number of strokes performed by a pump, to verify normal pump operation. It can also help determine preventative maintenance schedules.
6. Float Switch: This is one of the most common ways to automate a pump for dewatering applications. If the float switch is raised above the pump, sensors will allow the pump to begin working when water meets the required level, and switch off when the water level is low.
7. Frequency Drive: This can be specified for multiple functions, including measuring a motor RPM, power absorbed, or have a torque sensor.
8. Leakage Sensor: Sensors can be built into diaphragm metering, AOD, and peristaltic pumps to detect if a pump is leaking, and automatically stop. This helps ensure dangerous fluid does not leak or pose health risks.
9. Level Probes: Probes and sensors can be used in applications where pumps are dry mounted or immersed in fluid. Sensors can detect the height of the fluid and start and stop as needed, which is an alternative to float switches.
10. Pressure Transducer: This detects the pressure of fluid in a pipeline, and can speed up or slow down to match performance.
11. Probes: Level probes are conductive and work when win contact with fluid, which allows pumps to completely empty low levels of water.
12. Product Sensor: Pumps can be built with hoppers containing sensors that can automatically empty the hopper before starting again, reducing working time to only when the product is available.
13. Remote Monitoring: Containing data loggers, these devices enable users to monitor or determine if a fault as occurred, and why it happened. Flow, pressure, absorbed power, and vibration can be monitored remotely.
14. Stroke Counter: Stroke sensors can detect the number of strokes performed by an air operated diaphragm pump, which counts the number of times air is ejected from the exhaust, and stop the pump after the limit is reached.
15. Temperature Probe: On certain types of pumps, it is possible to monitor pressure of the bearings and stator to detect if the pump is working at an increased temperature, and can be stopped before damage occurs.
16. Timer: Control panels can be used to stop a pump from running past a certain amount of time, commonly used in dosing, recirculation, transfer, and injection applications.
17. Torque Sensor: This sensor built into an inverter can detect when a positive displacement pump is working strenuously or outside the normal limits. If calibrated correctly, it can prevent pressure build up in a discharge line.