Marwell and Maxwell Oil Tools save costs through innovative stop collar design

Source: press release, 29 July 2020

Installation of the Slimstop bonded composite stop collar
Installation of the Slimstop bonded composite stop collar (photo: Marwell/Maxwell Oil Tools)

Marwell, the specialist in bespoke wellbore construction and completion equipment, has successfully installed a tailored and cost-effective solution to replace centralizer subs for a major international oil company. The project was undertaken in close conjunction with its long-term partner, Maxwell Oil Tools.

A 17-inch liner was required to run through a 17.562-inch ID wellhead restriction to centralize the string sufficiently in the under reamed 20-inch open hole. Marwell AS worked closely with the operator and Maxwell Oil Tools to design an ultra-slim stop collar with exceptionally high holding force for the application. The selected product was the Slimstop bonded composite stop collar.

Taking place on a redevelopment of a mature field in the Norwegian North Sea, the well consisted of a chalk formation. To achieve the cementing objectives, the stop collars were run together with a third-party bow spring-type centralizer to give the required standoff in the under-reamed open hole. The resulting close tolerance stop collar application was independently verified as being extremely robust, and the operator successfully ran the 17-inch liner through the wellhead restriction and cemented it as planned. The robust bonded-to-pipe solution was installed at the Marwell installation facility in Stavanger at a fraction of the cost of using centralizer subs.

“Offering innovation and cost savings to clients in what is a challenging environment means they can realise savings of several days of rig time. This achievement means we have the ability to turn a borderline project into an economically viable one. In this case, our design effectively solved the operator’s challenge and allowed them to successfully adopt a robust bonded-to-pipe solution at a fraction of the cost,” says Mike Williamson, Managing Director of Marwell.

Specialising in wellbore construction and completion, Marwell AS offers tailored solutions that are not available elsewhere. Having demonstrated the value of MCC technology to the oil industry, and to support future growth, Marwell AS recently opened a new dedicated MCC centralizer installation facility in Stavanger. The 1,500 m2 facility has capacity for several hundred joints of casing per week to cater for the expected growth in demand for the MCC product line.