| 摘要 |
354,844. Coating pipes &c. STANDARD OIL CO. OF CALIFORNIA, 225, Bush Street, San Francisco, U.S.A. March 17, 1930, No. 20972/31. Convention date, Dec. 7, 1929. Divided on 354,803. [Class 87 (ii).] Pipes are coated by forming a layer of bituminous mastic on. a tape and then wrapping the tape round the pipe. The tape may be removed subsequently from the coated pipe. Preferably mastic of the kind described in Specification 354,803 is employed. Both pipe and plastic preferably are heated and the pipe may be covered initially with a layer of primary material. The pipe 8 is rotated and also moved longitudinally past a trough 4 through a slit in the base of which the tape 5 passes under tension from a storage reel and receives a layer of mastic from the hopper 1, both tape and mastic being wound spirally on the moving pipe. The mastic is tamped and levelled on the tape before passing to the pipe. The tape may comprise paper, cardboard, fabric or metal and may remain on the finished article or be removed. An endless metal tape may be employed which unwraps automatically after a predetermined number of revolutions of the pipe. The joints formed by the meeting edges of the wound tape may be covered by another narrow band of tape. Bituminous mastics of the emulsion type may be used which are applied to the tape in the cold state.
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