Positive Displacement Motors have a long and varied history in the Canadian Oilpatch. They are used for a number of purposes including directional drilling, performance drilling, river crossings, completions and utilities installations.

In recent years the “Disposable Motor” has become more and more commonplace, particularly in applications with high cost day rates, ie: offshore. In the offshore industry we see operators running “Disposable” motors on the end of their production string to ensure they get the casing to bottom. The motor allows the operator to drill or circulate through tight spots and bridges thus eliminating the need to trip casing and perform cleanout trips. In such applications where day rates are high, the cost of running a motor is very economical insurance.

Historically, utilization of “Disposable” motors has been very limited in Alberta due to cost. In past situations where an operator did require a “Disposable” motor for whatever purpose the vendor would send out a used, usually worn out motor. The thinking behind this development was to offer the client an affordable alternative in situations where a motor would be the practical solution.

“Operator had drilled and landed 7' intermediate casing at 2582m (90 degrees). 6 1/8" hole was drilled to 3900m. Problems were incurred open hole logging the well due to cuttings bed settling and deteriorating hole conditions. Decision was made to run a mud motor on the end of the liner string to allow us to circulate the liner into place to ensure the liner made it to bottom. Operations were successful as the mud motor was used to circulate the liner to bottom right from outside the intermediate casing to liner TD. It is our opinion that the liner would have not made it to bottom without the assistance of the mud motor.”

In this case a 5” “Disposable” motor was run. The operator was impressed with the results and the costs and maintains that this well would have been lost without the use of the motor.

In addition to conventional drilling hole sizes, “Disposable” motors are also available in smaller sizes, usually 2-7/8” or 3-1/8”. These are most commonly used in snubbing operations where the operator wishes to drill out plugs and drop the motor on bottom thereby eliminating the need for additional snubbing in and out of the wellbore. Small motors have a history of being used for sacrificial purposes. Where we differentiate ourselves is by offering “Main Hole” size “Disposable” motors to the market.

The “Disposable” motor is a proprietary tool purpose built for these applications. It can be provided in most sizes. Many components have been redesigned to lower the total cost thus making it an affordable alternative. Although these motors are labeled “Disposable” they have gone through rigorous testing and are built with only new components. In testing these motors easily drilled in excess of 100 hours.

Tags: The Motor Company