Claims
- 1. A coated pipe consisting essentially of a metal pipe having an exterior coating covering essentially the entire external surface of the pipe, said coating consisting essentially of
- about 50 to 70 wt. % of a mineral aggregate,
- about 5 to 20 wt. % of asphalt,
- about 15 to 35 wt. % of a finely divided mineral filler, and
- about 0.05 to 0.5 wt. % of synthetic organic fibers selected from the group consisting of polyester fibers, polyamide fibers, polyfluorocarbon fibers and poly(arylene sulfide) fibers.
- 2. A coated pipe in accordance with claim 1 wherein said mineral aggregate is sand.
- 3. A coated pipe in accordance with claim 1 wherein said finely divided mineral filler is limestone dust.
- 4. A coated pipe in accordance with claim 1 wherein said synthetic organic fiber is a poly(p-phenylene sulfide) fiber.
- 5. A coated pipe in accordance with claim 1 wherein said synthetic organic fiber has a length of about 1 to 15 mm and a fiber weight of about 1 to 16 denier.
- 6. A process for producing a coated pipe which comprises applying a layer of a composition consisting essentially of
- about 50 to 70 wt. % of a mineral aggregate,
- about 5 to 20 wt. % of asphalt,
- about 15 to 35 wt. % of a finely divided mineral filler, and
- about 0.05 to 0.5 wt. % of synthetic organic fibers selected from the group consisting of polyester fibers, polyamide fibers, polyfluorocarbon fibers and poly(arylene sulfide) fibers
- onto the external surface of a pipe.
- 7. A process in accordance with claim 6 wherein said layer is applied in a thickness of about 0.5 to 4 mm.
- 8. A process in accordance with claim 6 wherein the external surface of the pipe is first covered with a thin primer layer of asphalt having a thickness of about 0.05 to 1 mm, and wherein the layer of said composition is applied on top of this asphalt primer layer.
- 9. A process in accordance with claim 6 wherein said mineral aggregate, said finely divided mineral filler, and said synthetic organic fiber are mixed to form a dry mixture, wherein this dry mixture, having a temperature of about 175.degree. to about 260.degree. C., and molten asphalt having about the same temperature as said dry mixture are blended thoroughly to form a hot mastic and wherein this hot mastic is applied to the pipe.
Parent Case Info
This application is a division of application Ser. No. 680,836, filed Apr. 28, 1976, now U.S. Pat. No. 4,052,219.
US Referenced Citations (10)
Divisions (1)
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Number |
Date |
Country |
Parent |
680836 |
Apr 1976 |
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