Method and apparatus for cement lining of pipes
AssigneeRaymond International Builders, Inc.
InventorClifford A. Padgett
Life of this patent
Estimating the term…
Abstract
A pipe lining apparatus includes a distributor head which throws cement mortar centrifugally against the interior of a pipe, a trowel which smooths the cement mortar and a liquid coating spray applicator which applies a curing control substance to the trowelled lining. The spray applicator comprises an air atomizing device which produces a very fine coating spray and blows it onto the freshly applied mortar lining without disturbing the lining. Also, in one embodiment the coating spray application is mounted to swing laterally with the trowel so as to be maintained centrally in the pipe.
Claims25
A method of lining a pipe with cement mortar, said method comprising the steps of centrifugally spraying a wet cement mortar against the interior of the pipe, trowelling the wet cement mortar and, before the trowelled wet cement mortar begins to harden, supplying liquid coating material and compressed air to an air atomizing spray nozzle to produce an air atomized liquid spray, said liquid being of the type which forms a moisture barrier on the surface of the mortar, and applying the air atomized liquid spray onto the trowelled surface of said wet cement mortar to form said moisture barrier on said surface.
Apparatus for lining a pipe with a cement mortar lining, said apparatus comprising a centrifugal distributor head, a support for said head and constructed to move along against the inner wall of a pipe to be lined and to support said head centrally of the pipe, a trowel mounted behind the distributor head to be pulled along therebehind and to trowel mortar applied to the interior of said pipe, an air atomizing spray nozzle mounted to spray out behind said trowel onto the trowelled mortar lining in the pipe and means for supplying pressurized air and a moisture barrier forming liquid to said spray nozzle.
A method for lining a pipe with cement mortar, said method comprising the steps of distributing wet cement mortar onto the inner wall of said pipe by centrifugal action from a distributor head while moving the head through the pipe, pulling a trowel which is pivotally connected to and positioned behind said distributor head over the thus distributed mortar lining to smooth same while allowing relative lateral movement between the trowel and the distributor head as said distribution head and trowel successively negotiate bends in the pipe, and spraying a moisture barrier forming liquid onto the smoothed mortar lining from a spray nozzle while supporting said nozzle on said trowel at a location immediately therebehind, whereby the nozzle is maintained at all times at substantially the same distance from the trowelled surface of said mortar lining.
Apparatus for lining a pipe with cement mortar, said apparatus comprising a centrifugal distributor head, a support for said head and constructed to move along against the inner wall of a pipe to be lined and to support said head centrally of the pipe, a drag trowel for engaging and smoothing mortar applied to the interior of said pipe from said distributor head, means pivotally coupling said drag trowel and said distributor head so that said drag trowel will be pulled along through a pipe behind said distributor head and so that the trowel will be free to move laterally with respect to said distributor head when said distributor head and trowel successively negotiate bends in the pipe, a spray nozzle for spraying a moisture barrier forming liquid onto mortar smoothed by said trowel, and mounting means on said trowel for mounting said spray nozzle at a location immediately behind said trowel so that the nozzle is maintained at a predetermined distance from the trowelled surface of the mortar along the entire length of the pipe.
Dependencies are inferred from the claim text.