Various pipe-joining technologies have been developed over the years to increase pipeline lay speed and reduce installation cost. Particularly, the industry is interested to improve, or even eliminate, the welding process which is the bottleneck for pipeline installation cost reduction. Zap-Lok is a fast mechanical connection that doesn’t require welding and thus can improve the lay speed significantly. In addition, it is a repeatable process, requiring less skilled personnel and equipment. With over 40 years track record, with some 100,000+km installed it is now being adoted as a relativelively standard technology for marginal shallow water offshore concessions around the world.
By utilizing the Zap-Lok connection, pipelay rates can be improved by a factor of 4 over conventional welding. Moreover, owing to reduction in the amount of equipment required, it enables smaller pipelay vessels, or vessels of opportunity to be used where the day rates are substantially cheaper than the conventional pipelay barge.
Furthermore, by embracing internal plastic coating technology (IPC) in concert with Zap-Lok it is possible to utilize the pipe wall body for on-bottom stability and dispense with expensive concrete weight coating (CWC) thus reducing raw material costs and offshore rates further due to the increase in pipe that can be stocked on the pipelay vessel. This paper will seek to demonstrate the performance of the connection in an offshore environment, drawing upon numerical modelling and empirical data to prove it is more than fit for purpose.