Method and apparatus for predicting maintenance needs of a pump based at least partly on pump performance analysis

Abstract

A signal processor is provided comprising one or more signal processor modules configured to: compare signaling containing information about historical data related to the performance of a pump; and provide corresponding signaling containing information about predicted maintenance needs of the pump on a real time basis based at least partly on the signaling compared containing information about the historical data related to the performance of the pump. The one or more signal processor modules may be configured to compare over time the hydraulic power generated by the pump and electric power consumed by a motor driving the pump, including tracking a ratio of hydraulic to electric power. The one or more signal processor modules may be configured to predict maintenance needs based on an algorithm that takes into account a trade-off between the cost of power consumed by a motor driving the pump and the cost associated with the pump maintenance in order to substantially minimize the total cost of operating the pump.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims benefit to provisional patent application Ser. No. 61 / 186,502, filed 12 Jun. 2009, which is hereby incorporated by reference in its entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The field of the invention relates to a technique predicting maintenance needs of a pump, including large diameter slurry pumps.[0004]2. Description of Related Art[0005]Pumps need to be maintained during the course of their lifetime. Pumps that are well maintained have a tendency to operate longer and more efficiently than pumps that are not well maintained.[0006]By way of example, maintenance may be carried out to prolong the lifetime of a pump, or to increase the efficiency of the pump, or both. An example of lifetime prolonging maintenance is the dynamic balancing of impellers which reduces vibration and thereby increases the lifetime of a pump. An example of maintenance geared to increase efficiency is the rep...

AI Technical Summary

Benefits of technology

The invention described in this patent has specific features and arrangements of parts that make it up. These features are efficient in achieving the objectives set forth and can be modified without changing the scope of the invention. The patent text is meant to be interpretative and not limiting in its scope.

Problems solved by technology

There is absolutely no hydraulic pump theory backing it up.

Theory only stipulates a relation between the head and the flow coefficient but theory does not predict the shape of such a relation.

Such a pump would not be practical because of the mechanical friction that the impeller would impart on the pump casing.

It is not in general possible to overcome this by interpolation on non-missing points as the intervals containing missing values can be rather long.

Such unphysical values may be measurement error but they may also be the result of a process condition that is not representative of normal operations.

Obviously this type of behaviour is not desired.

Yet, the efficiency curve shows an upward curving tail at high flow coefficients which is not possible in a real pump.

The entire spike around that period, which disturbs the downward trend of the pump efficiency which is otherwise visible is suspect.

It is possible that the current probe may have been replaced around that day and was not properly recalibrated until some days later.

Contrariwise, those events will be visible in all of the four plot and may thus be much harder to identify.

If those clearances increase due to wear there will be increased internal recirculation inside the pump which causes the pressure and discharge flow to be less than optimum.

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