Polymer pipe connection and method to make it

• US 4,070,044 A
• Filed: 01/22/1976
• Issued: 01/24/1978
• Est. Priority Date: 01/22/1976
• Status: Expired due to Term

• Current Assignee: Phillips Petroleum Company (ConocoPhillips)
• Original Assignee: Phillips Petroleum Company (ConocoPhillips)
• Inventors: Carrow, Guy E.
• Primary Examiner(s): Callaghan, Thomas F.
• Application Number:
  US05/651,311
• Time in Patent Office: 733 Days
• Field of Search: 285/381, 285/DIG. 10, 285/423, 285/DIG. 16, 285/156, 285/155, 264/230, 264/249, 156/86, 156/245
• US Class Current: 285/133.11
• CPC Class Codes: B29C 61/00 Shaping by liberation of internal stresses; Making preforms having internal stresses; Apparatus therefor for surface shaping B29C59/18; for lining articles B29C63/38; for joining preformed parts B29C65/66 ; for packaging B65B53/00; connecting arrangements or other fittings for plastics pipes using shrink-down material F16L47/22, electrical connections insulated using heat shrinking insulating sleeves H01R4/72; cable junctions protected by sleeves H02G15/18
• CPC Class Codes: B29C 65/1412 Infrared [IR] radiation
• CPC Class Codes: B29C 65/4835 Heat curing adhesives
• CPC Class Codes: B29C 65/5057 positioned between the surfaces to be joined B29C65/5035 takes precedence
• CPC Class Codes: B29C 65/68 using auxiliary shrinkable elements
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/1142 Single butt to butt joints
• CPC Class Codes: B29C 66/5224 for forming fork-shaped connections, e.g. for making Y-shaped pieces
• CPC Class Codes: B29C 66/52241 with two right angles, e.g. for making T-shaped pieces
• CPC Class Codes: B29C 66/5229 involving the use of a socket
• CPC Class Codes: B29C 66/52292 said stop being internal
• CPC Class Codes: B29C 66/63 Internally supporting the article during joining B29C66/49 takes precedence
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/73 characterised by the intensive physical properties of the material of the parts to be joined, by the optical properties of the material of the parts to be joined, by the extensive physical properties of the parts to be joined, by the state of the material of the parts to be joined or by the material of the parts to be joined being a thermoplastic or a thermoset
• CPC Class Codes: B29C 66/7371 oriented or heat-shrinkable
• CPC Class Codes: B29C 66/73715 heat-shrinkable
• CPC Class Codes: B29C 66/73751 the to-be-joined area of at least one of the parts to be joined being uncured, i.e. non cross-linked, non vulcanized
• CPC Class Codes: B29C 66/73755 the to-be-joined area of at least one of the parts to be joined being fully cured, i.e. fully cross-linked, fully vulcanized
• CPC Class Codes: B29C 66/7392 characterised by the material of at least one of the parts being a thermoplastic
• CPC Class Codes: B29C 66/7394 characterised by the material of at least one of the parts being a thermoset
• CPC Class Codes: B29K 2023/00 : Use of polyalkenes or derivatives thereof as moulding material
• CPC Class Codes: B29K 2023/06 : PE, i.e. polyethylene
• CPC Class Codes: B29K 2023/065 : HDPE, i.e. high density polyethylene
• CPC Class Codes: B29K 2023/0691 : PEX, i.e. crosslinked polyethylene
• CPC Class Codes: B29K 2023/08 : Copolymers of ethylene B29K2023/16 takes precedence
• CPC Class Codes: B29K 2023/10 : Polymers of propylene
• CPC Class Codes: B29K 2023/12 : PP, i.e. polypropylene
• CPC Class Codes: B29K 2023/18 : Polymers of hydrocarbons having four or more carbon atoms, e.g. polymers of butylene, e.g. PB, i.e. polybutylene
• CPC Class Codes: B29K 2105/0085 : Copolymers
• CPC Class Codes: B29K 2105/24 : crosslinked or vulcanised
• CPC Class Codes: B29K 2105/246 : Uncured, e.g. green
• CPC Class Codes: B29L 2031/24 : Pipe joints or couplings B29L2031/26 takes precedence
• CPC Class Codes: B29L 2031/246 : T-joints
• CPC Class Codes: F16L 47/22 : using shrink-down material
• CPC Class Codes: Y10S 285/909 : Fluorocarbons and memory plastics

Abstract

A pipe connection is provided which comprises two pipe ends, one inserted inside of the other, and one consisting essentially of crosslinked polymer material, whereas the other consists essentially of crosslinked or non-crosslinked polymer material, the connection having a layer of polymer material press-fitted and crosslinked between the two pipe ends. The pipe fitting is made by arranging the two pipe ends so that one is inserted in the other, one of the ends having a mechanical memory and having been deformed so that one of the pipe ends fits into the other, providing an in situ heat-crosslinkable polymer layer between the two pipe ends and heating the thus assembled pipe ends to crosslink the heat-crosslinkable layer, while the deformed pipe end returns towards its original shape, thus press-fitting the crosslinking polymer layer between the two pipe ends and making a strong, fluid-tight joint.

Claims

1. A modified multiple-outlet pipe fitting which comprises

a. a base pipe fitting formed of a crosslinked polymer and having at least three outlets,

b. at least three segments of conduit having a first end and a second end and being formed of a non-crosslinked polymer, so positioned that each first end of each segment of conduit is positioned adjacent one outlet of said base fitting and wherein each segment of conduit is essentially of the same internal diameter as that outlet of said base fitting to which it is positioned adjacent,

c. a heat-deformed sleeve member disposed around each of said outlets of said base fitting and said first end of each segment of conduit, each said member having been formed from a heat-deformable polymer and being sealably connected to each said fitting outlet and segment of conduit by

d. a seal formed of an in situ crosslinked polymer material having been disposed between the inner surface of each sleeve member and the outer surface of each outlet of said base fitting and each first end of each segment of conduit abutted thereto.

2. A modified fitting according to claim 1 wherein said in situ crosslinked polymer material is further disposed between the abutting surfaces of said outlets and said first ends of said conduits so as to form a gasket member between same.

3. A modified fitting according to claim 1 wherein said polymers are individually selected from the group consisting of homopolymers and copolymers of 1-olefins having 2 to 8 carbon atoms.

4. A modified fitting according to claim 3 wherein said polymers are individually selected from the group consisting of polyethylene, polypropylene, polybutene-1, and copolymers of ethylene with 1 to 8 mol percent of 1-butene, and copolymers of ethylene with 1 to 8 mol percent of 1-hexene.

5. A modified fitting according to claim 1 wherein said seal was formed from a non-crosslinked but heat-crosslinkable polyolefin.

6. A modified fitting according to claim 5 wherein said seal was formed from a mixture consisting of polyolefin and an acetylenic diperoxy hydrocarbon crosslinking agent.