Dope-free technology is a dry multilayer coating that provides key advantages during the make-up process of the connections under extreme conditions compared to doped technology. The dry coating doesn't need a reapplication after the repeated break and make of connection, meanwhile providing more consistent make-up performance. (Castineiras, T., Nunez, A., Gallo, E., and Carcagno, G. E. 2009)
The use of dope-free Technology tubulars in offshore and onshore operations has been increasingly adopted by multiple operators since the first running that took place in the North Sea in 2003. Dope-free tubulars replace the storage and running pipe dope historically used in casing and tubing by a dry coating applied on pipe threads in an industrial controlled environment. The elimination of dope greatly simplifies the supply chain process involved in preparing casing and tubing for onshore and offshore wells, thus increasing efficiency and safety and lessening the environmental impact of the process.
The benefits of dope-free technology can be divided in 4 main macro-areas:
Environmental benefits, health and safety benefits, improved well productivity and improved operational performance. Dope-free technology does not have any environmental impact: the compound layers are thin films of dried chemicals and they are not displaced into the tubes nor into the environment during the offshore installation of the pipes. According to a study performed by Det Norske Veritas (DNV, i.e. a Norwegian classification society with the objective of "Safeguarding life, property, and the environment"), dope-free technology represents a significant step forward for the environmental protection.
Concerning H&S benefits, dope-free technology brings a significant improvement. This comes as a result of eliminating certain operations required when using standard material (with dope) that will expose employees to risks: the exposure of the workers to potential incidents/accidents risks related to tubulars handling is significantly reduced. According OHSAS 18001: 2007, the elimination of the task is the first action in order to reduce and control the risk.
Dope-free technology allows many operational benefits during the field assessment: all these benefits could assure an increased efficiency (i.e. faster installation, reduced number of rejects and re-make ups, elimination of risk related to improper thread compound application, no need of cleaning storage compound) and an increased reliability (i.e. more consistent make-up operations and no improper dope application caused by human errors).
A tubing string that has been over-doped, the excess of dope might result in reduction of permeability and blockage of flow path due to plugging of porous formation. In addition, the excess lublicant can clog valves, sandscreens and heads of the perforating guns. Nevetheless, the biggest problem that can be due to excess of dope is on the near-well zone because thread compounds are not easily soluble by both water and oil-based solvents. (De Franceschi, E., Castineiras, T., Benedetto, F., Funes, A., Figini, F., and Economides, M. J. 2013)
These are the main reasons why dope-free technology can bring important benefits to well productivity and post-running operations.