Method of assembling a thermoplastic sleeve onto a pipe or the like

• US 3,929,538 A
• Filed: 06/14/1974
• Issued: 12/30/1975
• Est. Priority Date: 06/14/1974
• Status: Expired due to Term

• Current Assignee: Leverne G. Diebel
• Original Assignee: Leverne G. Diebel
• Inventors: Diebel, Leverne G.
• Primary Examiner(s): Drummond, Douglas J.
• Assistant Examiner(s): Frisenda, F.
• Application Number:
  US05/479,743
• Time in Patent Office: 564 Days
• Field of Search: 156/86,85,157,158,160,165,295,296,293,294,303.1,282,322 264/89,322,92,327,237,348 285/381,223,DIG.10 138/DIG.1,DIG.5,120,155
• US Class Current: 156/86
• CPC Class Codes: B29C 57/00 Shaping of tube ends, e.g. flanging, belling or closing; Apparatus therefor , e.g. collapsible mandrels
• CPC Class Codes: B29C 65/48 using adhesives , i.e. using supplementary joining material; solvent bonding
• CPC Class Codes: B29C 65/66 by liberation of internal stresses, e.g. shrinking of one of the parts to be joined
• CPC Class Codes: B29C 65/665 using shrinking during cooling
• CPC Class Codes: B29C 65/72 by combined operations or combined techniques, e.g. welding and stitching
• CPC Class Codes: B29C 66/1222 comprising at least a lapped joint-segment
• CPC Class Codes: B29C 66/1224 comprising at least a butt joint-segment
• CPC Class Codes: B29C 66/131 Single flanged joints, i.e. one of the parts to be joined being rigid and flanged in the joint area
• CPC Class Codes: B29C 66/5344 said single elements being substantially annular, i.e. of finite length, e.g. joining flanges to tube ends B29C66/5346 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 66/73161 Roughness or rugosity
• CPC Class Codes: B29K 2023/065 HDPE, i.e. high density polyethylene
• 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 2025/06 PS, i.e. polystyrene
• CPC Class Codes: B29K 2027/06 PVC, i.e. polyvinylchloride
• CPC Class Codes: B29K 2033/08 Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate
• CPC Class Codes: B29K 2033/12 Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate
• CPC Class Codes: B29K 2059/00 Use of polyacetals , e.g. POM, i.e. polyoxymethylene or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2067/00 Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2077/00 : Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• CPC Class Codes: B29L 2031/24 : Pipe joints or couplings B29L2031/26 takes precedence

Abstract

A method for assembling a thermoplastic sleeve coupling onto the end of a pipe is disclosed wherein an end of the coupling is heated to a thermoplastic temperature and is selectively flared whereafter the flared end is assembled onto the end of the pipe and caused to return to substantially its non-flared configuration to compress an adhesive sealant between the coupling and the pipe.

Claims

1. A METHOD FOR ASSEMBLING A THERMOPLASTIC TUBULAR SLEEVE OVER THE END OF A PIPE OR THE LIKE, SAID PIPE HAVING AN ADHESIVE MATERIAL DISPOSED ON THE END THEREOF RECEIVED WITHIN SAID SLEEVE, AND SAID SLEEVE HAVING AN OUTER MOST END AND AN INNER PERIPHERAL CONFIGURATION WHICH WOULD NORMALLY CAUSE THE ADHESIVE MATERIAL TO BE WIPED ALONG THE SURFACE OF SAID PIPE FORWARDLY OF SAID OUTERMOST END OF THE SLEEVE AS IT IS ASSEMBLED COAXIALLY OVER THE END OF THE PIPE, SAID METHOD COMPRISING THE STEPS OF HEATING AT LEAST THE END PORTION OF SAID SLEEVE TO BE RECEIVED OVER THE END OF SAID PIPE TO A TEMPERATURE RENDERING SAID HEATED PORTION OF SAID SLEEVE THERMOPLASTIC, DEFORMING THE OUTERMOST END AND A FIRST PREDETERMINED AXIAL LENGTH OF SAID HEATED END OF SAID SLEEVE TO A CONFIGURATION HAVING AN INNER SURFACE CIRCUMFERENCE GREATER THAN THE OUTER SURFACE CIRCUMFERENCE OF SAID END OF SAID PIPE SO THAT SAID DEFORMED END OF SAID SLEEVE MAY BE RECEIVED OVER SAID END OF SAID PIPE AND SAID ADHESIVE MATERIAL DISPOSED THEREON WITHOUT WIPING SAID ADHESIVE ALONG SAID END AND A CONTIGUOUS SECOND PREDETERATURE OF SAID OUTERMOST END AND A CONTIGUOUS SECOND PREDETERMINED AXIAL LENGTH OF SAID HEATED END OF SAID SLEEVE TO A TEM-

2. The method as defined in claim 1 wherein said step of heating said end portion of said sleeve comprises heating a sufficient portion of said sleeve to establish a source of residual heat capable of causing said second predetermined axial length of said sleeve to return to a thermoplastic temperature after assembling said sleeve onto said pipe such that said deformed end portion of said sleeve may thereafter return to a substantially non-deformed configuration upon cooling due to the thermal memory of the sleeve material.

3. The method as defined in claim 1 wherein said step of deforming said first predetermined axial length of said sleeve comprises forcing said first axial length of said sleeve over a mandrel having a tapered flaring surface thereon adapted to effect an outward flaring of said first predetermined length of the sleeve.

4. The method as defined in claim 3 wherein said step of reducing the temperature of a second predetermined axial length of said sleeve is accomplished by submerging said second predetermined axial length of said sleeve into a chilling liquid substantially simultaneously with flaring said first predetermined length of said sleeve.

5. The method as defined in claim 1 wherein said step of reducing the temperature of said second predetermined axial length of said sleeve comprises quenching said second predetermined axial length of said sleeve to a temperature substantially below the thermoplastic temperature to which said end portion of said sleeve was heated prior to deforming first predetermined length of said sleeve whereby to maintain said deformed length of said sleeve in its deformed configuration until it is again heated to a thermoplastic temperature by the residual heat retained in said sleeve.

6. A method for assembling a thermoplastic coupling sleeve having a generally cylindrical tubular end portion onto an end of a cylindrical pipe having an adhesive applied onto the peripheral surface of said pipe end, said tubular end portion of said coupling sleeve having a normal configuration sufficient to cause said adhesive to be wiped from said surface of said pipe by the leading edge of said sleeve when assembled onto said pipe while said coupling sleeve is in its said normal configuration, said method comprising the steps of;

heating at least the end portion of said sleeve to be received over said end of said pipe to a temperature sufficient to render said end portion of said sleeve thermoplastic, flaring a first predetermined axial length of the heated end of said sleeve to a configuration sufficient to be received over said end of said pipe and the adhesive material disposed thereon without wiping said adhesive from said surface of said pipe, cooling a second predetermined axial length of said flared length of said sleeve less than said first axial length to a temperature substantially below said thermoplastic temperature of said end portion of said sleeve to retain said flared configuration, assembling said heated end portion of said sleeve coaxially onto said end of said pipe so that at least said flared end poRtion of said sleeve is received over said adhesive material disposed on said pipe, causing said cooled length of said sleeve to be raised to a thermoplastic temperature by the residual heat within said remaining heated end portion of said sleeve, and thereafter allowing all of said heated end portion of said sleeve to cool to ambient temperature such that said flared end portion thereof returns to substantially its normal configuration to compress said adhesive disposed between said sleeve and said pipe.