Abstract: A welding support block supports, from the rear surface of a joint to be welded, a weld pool created during a welding process. The welding support block comprises a block of metal and an outer layer of ceramic material providing a supporting surface. The ceramic material layer has a thickness between 0.25 mm and 1.5 mm. The metal material immediately beneath the ceramic material layer is made of steel. An internal line-up clamp for holding pipes in end-to-end alignment ready for welding may include multiple such welding support blocks. The use of such welding support blocks is particularly useful when laying a sour service carrying pipeline (high H2S content).

Abstract: A welding support block supports, from the rear surface of a joint to be welded, a weld pool created during a welding process. The welding support block comprises a block of metal and an outer layer of ceramic material providing a supporting surface. The ceramic material layer has a thickness between 0.25 mm and 1.5 mm. The metal material immediately beneath the ceramic material layer is made of steel. An internal line-up clamp for holding pipes in end-to-end alignment ready for welding may include multiple such welding support blocks. The use of such welding support blocks is particularly useful when laying a sour service carrying pipeline (high H2S content).

Abstract: A method for repairing a defective circumferential weld joint between two pipe sections in a pipeline is described. A weld excavation machine is used to remove a weld defect. The machine comprises a weld excavating tool and a tool guiding apparatus. The machine may be modular in form allowing the machine to be dissembled into discrete portable parts. The method includes arranging the tool guiding apparatus in fixed relation to the pipeline, guiding the weld excavating tool around the pipe and along the weld joint by means of the tool guiding apparatus and using the weld excavating tool to remove material from the defective weld region. An excavation may thus be formed having parallel vertical walls. The excavation is then filled with weld material by means of a welding apparatus.

Abstract: The present invention relates to a polyurethane polymer prepared from a mixture comprising: (a) at least one polyol of formula (I), wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated polyoxyalkylene group, and the remainder of X1, X2, X3. X4 and X5 are each independently H or absent, and Z is a central linking unit; (b) at least one di- or poly-isocyanate; and (c) optionally at least one OH-terminated chain extender. Further aspects of the invention relate to a process for preparing a polyurethane, and to a process for preparing a contact lens.

Abstract: A method of laying a pipeline is described in which both internal and external weld passes are performed in order to weld together the pipe sections. The method includes arranging a pipe section adjacent to the end of a pipeline thereby defining a circumferential joint to be welded, performing an external weld pass, with for example GMAW—MIG torches, on the root of the joint to be welded during which weld material is deposited in the root of the joint to be welded, thereby forming a root weld, and then performing an internal weld pass, with for example a GTAW—TIG torch, on the root weld during which the root weld is melted and re-shaped. The method has particular application in relation to pipes clad with corrosion resistant alloy.

Abstract: The present invention relates to a thermoplastic polyurethane contact lens prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; and (c) at least one diol of formula (I): wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a contact lens.

Abstract: The present invention relates to a polyurethane prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; (c) at least one polydialkyl siloxane diol; and (d) at least one diol of formula (I) wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate, polydialkyl siloxane diol and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a polyurethane.

Abstract: The present invention relates to a polyurethane polymer prepared from a mixture comprising: (a) at least one polyol of formula (I), wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated polyoxyalkylene group, and the remainder of X1, X2, X3. X4 and X5 are each independently H or absent, and Z is a central linking unit; (b) at least one di- or poly-isocyanate; and (c) optionally at least one OH-terminated chain extender. Further aspects of the invention relate to a process for preparing a polyurethane, and to a process for preparing a contact lens.

Abstract: A method for repairing a defective circumferential weld joint between two pipe sections in a pipeline is described. A weld excavation machine is used to remove a weld defect. The machine comprises a weld excavating tool and a tool guiding apparatus. The machine may be modular in form allowing the machine to be dissembled into discrete portable parts. The method includes arranging the tool guiding apparatus in fixed relation to the pipeline, guiding the weld excavating tool around the pipe and along the weld joint by means of the tool guiding apparatus and using the weld excavating tool to remove material from the defective weld region. An excavation may thus be formed having parallel vertical walls. The excavation is then filled with weld material by means of a welding apparatus.

Abstract: The present invention relates to a polyurethane polymer composition comprising polyethyleneglycol dialkyl ether. There is also provided a process for preparing a polyurethane. The invention also relates to a process for preparing a polyurethane xerogel in the form of a molded article, said process comprising the steps of: i. preparing a mixture of a. at least one polyethylene glycol or at least one polyol of formula (I), wherein at least three Of X1, X2, X3, X4 and X5 are each independently an OH-terminated group, and the remainder of X1, X2, X3, X4 and X5 are each independently H or absent, and Z is a central linking unit, a. at least one di- or poly-isocyanate, b. optionally at least one OH-terminated chain extender, and c. at least one polyethyleneglycol dialkyl ether; ii. dispensing the reaction mixture formed in step i) into a mold; iii. allowing the reaction mixture to react and cure; iv. removing the molded article from the mold; and v. hydrating the molded article.

Abstract: The present invention relates to a polyurethane prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; (c) at least one polydialkyl siloxane diol; and (d) at least one diol of formula (I) wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate, polydialkyl siloxane diol and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a polyurethane.

Abstract: The present invention relates to a thermoplastic polyurethane contact lens prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; and (c) at least one diol of formula (I): wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a contact lens.

Abstract: A method of laying a pipeline is described in which both internal and external weld passes are performed in order to weld together the pipe sections. The method includes arranging a pipe section adjacent to the end of a pipeline thereby defining a circumferential joint to be welded, performing an external weld pass, with for example GMAW—MIG torches, on the root of the joint to be welded during which weld material is deposited in the root of the joint to be welded, thereby forming a root weld, and then performing an internal weld pass, with for example a GTAW—TIG torch, on the root weld during which the root weld is melted and re-shaped. The method has particular application in relation to pipes clad with corrosion resistant alloy.

Abstract: The present invention relates to a method of using non-macrogelled polymer-solvent combinations to form devices, in particular medical devices and/or cosmetic devices, more specifically contact lenses. The method of using polymer solvent combinations is suitable for forming useful 3D dimensionally stable structures which may include curved surfaces, which may be significantly different to those curved surfaces achieved by using simple meniscus effects.