Marginal Column

Rent-a-pump

July 2013

 

The type R7 hydraulic drive for down hole pumps can be perfectly matched to conditions prevailing at oil fields. An example from Indonesia shows how.

 
 

Renting instead of owning? This trend is making headway in central Europe – in the form of car sharing for personal transportation. That has been quite common in a surprising market for some time now: petroleum production. In Indonesia, for example, the needed equipment is normally rented. Once a pool is exhausted, the pumps are dismantled, moved to the next location, and then pump that black gold on behalf of a new operator. Consequently, the local rental industry attaches great value to the pumps being not just efficient, but also light, simple to assemble and easy to relocate. This had been difficult in the past in a market dominated by the “nodding donkeys”, weighing about 15 tons.

The crude oil pump at work in Indonesia.

The crude oil pump at work in Indonesia.

 

Adaptable drive

The Wanda Group, in China, recognized the potential offered by the Rexroth R7 pump drive and, since 2011, has had great success on its local market. This drive system comprises the hydraulic power unit, cylinder, and accessories for the frame. Mounted right on the wellhead, the system requires no foundation and is nonetheless rugged and highly efficient. Tipping the scales at just three tons, this drive can effortlessly lift a load weighing as much as 20 tons.

In addition, the easy-to-operate unit is extremely versatile. The high-end version offers maximum pumping precision thanks to a modern path measurement sensor. This system makes remote diagnosis and command – using the PC in the control room – both convenient and quick. The hydraulic power unit can be set up inside a container to permit use in an environment where noise could be a problem.

Demanding rental use

In the sparsely settled Indonesian production fields, the equipment’s noise level is only of secondary importance for the customer. Indonesia Petroleum Corporation, however, was highly concerned that equipment used for rental service be rugged, easy to move, and simple to operate. That is why the Wanda Group, working with Bosch Rexroth, developed a system fully adapted to the environment. The down hole pump drive systems in use so far, numbering about one hundred, are a simplified version and thus lower in cost. Substituting for the more expensive path sensor, limit switches at the hydraulic cylinder trigger the lifting and lowering strokes.

Instead of implementing remote diagnosis and control from the field office, the operator sets just a few parameters right at the drive – and it gets right to work. This is an additional advantage for use in rental service. The systems move regularly from field to field and the current operator need not set up a control system. “Once it’s been put in service, the system runs trouble-free from the first moment on,” are one Indonesian engineer’s words of praise.