METHOD AND APPARATUS FOR LAYING PIPELINES FROM A REEL BARGE

摘要

1312592 Straightening FLUOR OCEAN SERVICES Inc 19 April 1971 [26 Jan 1970 (3)] 20057/71 Heading B3E [Also in Divisions B8 and F2] A metal pipeline 16 unwound from a reel 12, Fig. 1, rotatably mounted on a floating platform 10, is plastically bent to a constant radius of curvature in apparatus 50, then straightened in apparatus 24 and then moved into the water overlying the desired final location of the pipeline on the bed. A device 42 maintains a tension in the length of pipeline extending back to the reel. In operation, the vertical position of the components 50, 24 and 42 on guide posts 26 is adjusted in accordance with the varying vertical position of successive coils withdrawn from the reel 12. Straightening apparatus 24 comprises identical straightening and guiding shoes 52 and 54, respectively, located on opposite sides of the pipeline. Each shoe, Fig. 7, comprises an endless chain provided with rollers 268, for moving round a track 214-210-212-210, and with blocks 262, 262SP1/SP having soft, arcuate, pipeengaging faces (278, Figs. 8 and 9). Track section 214, along which the blocks 262 engage the pipeline, is flexible and is supported by pistons 230, reciprocable in connected cylinders, which collectively enclose a fixed volume of hydraulic fluid, so that longitudinally-spaced, uniform loads are applied to track section 214. Each shoe 52, 54 is displaceable transversely of the pipeline by hydraulic cylinders 290. Benaing apparatus 50 comprises an endless chain 406, Fig. 15, similar to those employed in shoes 52, 54, movable round a track including an arcuate portion, where the constant radius bend is imparted to the pipeline. An hydraulic cylinder 416 acts through cables 422, 424 to control the vertical positioning of the bending, straightening and tensioning apparatus on the posts 26, Fig. 1. Tensioning apparatus 42 comprises two chains 46, 48, Fig. 10, similar to those employed in shoes 52, 54. Each chain is driven by two sprockets (not shown) in turn driven by hydraulic motors 380. The two chains are housed in respective casings 302, 304, the separation between which can be adjusted by hydraulic cylinders 306, 308.