If your pump is costing you too much money then consider a pump service that will save energy and money in the future.

Pump efficiency deteriorates over time, leading to energy wastage. Efficiency losses of between 5 and 15% can occur after 10 years of operation. When pumps are maintained to restore efficiency close to its original point, significant energy savings can be achieved. Typically, a pump overhaul includes; replacement of wear rings, seals, bearings and if worn, the impeller; cleaning the internals; blast cleaning of externals; and apply new epoxy coating.

Background


Pumping is a major expense in broadacre farming and even small savings achieved through pump maintenance can have a noticeable impact in reducing overall energy costs.
Pump wear comes from excessive starting and stopping, pump cavitation and erosion from particulate material.
In the absence of regular maintenance, pump performance deteriorates steadily. Typically, a drop in efficiency of between 5 to 15% occurs after 10 years of operation.
When pumps are maintained to keep their efficiency close to its original point, significant energy saving can be made.
A pump overhaul may include: replacement of wear rings, seals and bearings and if worn, the impeller; cleaning of the internals; blast cleaning of casing externals; and the application of new epoxy coating.

Technical explanation.


When a pump wears, it tends to generate less flow and head, requiring more power to achieve the desired output. 
Studies have shown that:
Much of the wear occurs in the first few years,
After about 10 years the wear trends to level out,
The overall drop in efficiency for an unmaintained pump can be around 10 to 12.5%
An unmaintained pump can reach catastrophic failure after around 20 years’ service, and
Periodically maintaining the pump can return its efficiency to a level close to that of a new pump (UK Department of Environment, 1998)

Key factors when evaluating quotes.


Compare the actual pumping efficiency with the original efficiency, as given in the manufacturer’s specifications.
Measure the efficiency before and after the overhaul of your pump to determine the improvement in efficiency.
Determine the optimal maintenance cycle by looking at the time between the last pump overhaul and the pump’s efficiency reaching a new set low limit. These parameters will allow you to evaluate the cost/benefit of each overhaul.

Most pump parts are generally standard-designed and in terms of key parameters, there is little to differentiate them. However, there are a few points to consider:

When replacing a standard impeller, look for high-efficiency designs to improve pumping efficiency. If the pump is oversized, select an impeller with a smaller diameter to match the specific system requirement and reduce energy consumption.
When replacing metallic wear rings, consider using non-metallic ones (e.g.’ those made of thermoplastic composite material) which reduce friction and flow recirculation from the discharge side of the impeller back to the suction side, thus improving pump efficiency by typically 2 to 4%. These wear rings are more expensive than the metallic ones, but paybacks are generally good (<3yrs), particularly for pumps with high maintenance costs.
If your pump’s internal surfaces are heavily eroded and/or corroded, consider applying smooth epoxy coating, which can improve the efficiency of the pump by 1 to 5% and provide better protection against corrosion and erosion, extending pump life and reducing maintenance costs.

References
A report by Farm Energy Innovation Program - Energy & Irrigation
NSW Farmers