Prelay Crossing Supports
Pipeline crossing sleepers are generally assumed to be constructed of cumbersome and expensive reinforced concrete or solid steel, which, due to their size and weight, normally require a derrick barge and possibly an additional material barge offshore for installation purposes.
ULO offers an alternative to the reinforced concrete sleepers in the form of fabric formwork sleepers.
Essentially, these sleepers are manufactured to the required shape and size of the sleeper, positioned on the seabed by divers or ROV, then filled with grout, whilst on the sea bed. Once cured, the sleeper is ready to accept the new pipeline.
ULO prelay grouted in-situ sleepers are a fast and simple way of providing support prior to pipelay.
The crossing can be prepared with a series of prelay supports of correct spacing and height or with a single prelay support only near the crossing point and additional postlay supports type Standard or Large Base according to the curvature of the crossing pipeline and the allowable freespan length.