Mechanical joint bell adapter for polyethylene pipe

• US 6,983,960 B2
• Filed: 12/22/2003
• Issued: 01/10/2006
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: Georg Fischer Central Plastics, LLC (Georg Fischer AG)
• Original Assignee: Independent Pipe Products Inc (Georg Fischer AG)
• Inventors: Svetlik, Harvey E.
• Primary Examiner(s): DUNWOODY, AARON M
• Application Number:
  US10/743,395
• Publication Number:
  US 20050134044A1
• Time in Patent Office: 750 Days
• Field of Search: 285/113, 285/108.3, 285/37, 285/339, 285/342, 285/343, 285/374
• US Class Current: 285/337
• CPC Class Codes: F16L 21/04 in which sealing rings are compressed by axially-movable members for joints using a threaded member F16L19/07; quick acting couplings F16L37/00; devices for covering leaks from inside a pipe F16L55/162
• CPC Class Codes: F16L 21/08 with additional locking means F16L17/035, F16L17/04, F16L21/04, F16L21/06 take precedence; screwed joints F16L19/08; couplings of the quick-acting type F16L37/00
• CPC Class Codes: F16L 23/028 the flanges being held against a shoulder
• CPC Class Codes: F16L 25/0072 Joints for pipes of dissimilar materials non-disconnectible joints for pipes of dissimilar materials F16L13/007; joints between metal and plastic pipes F16L47/24

Abstract

A pipe coupling is shown for coupling adjacent ends of a pair of pipe sections where one of the pipe sections is formed of a polyolefin and the other pipe section is formed of a different material. The coupling includes an adapter formed of a length of pipe having a polyolefin pipe wall, the adapter having a fusing end for fusing to a successive length of polyolefin pipe and a coupling end. The coupling end has an integral flange which defines a bell end opening for the adapter. The bell end opening has a first region of reduced internal diameter for receiving a sealing gasket. The bell end opening also has a second region of further reduced internal diameter which forms a circumferential shoulder region therein for receiving a male spigot end of a mating pipe which is formed of the different material. A rigid reinforcing ring circumscribes an outer peripheral surface of the adapter flange in order to strengthen the connection when the spigot end of a mating male pipe is inserted within the bell end opening of the adapter to form the pipe coupling.

Claims

1. A pipe coupling for coupling adjacent ends of a pair of pipe sections where one of the pipe sections is formed of a polyolefin and the other pipe section is formed of a different material, the coupling comprising:

an adapter formed of a length of pipe having a polyolefin pipe wall, the adapter having a fusing end for fusing to a successive length of polyolefin pipe and a coupling end;

wherein the coupling end of the adapter has a nominal thickness pipe wall with an integral flange formed at one end thereof,

wherein the integral flange defines a bell end opening for the adapter, the bell end opening having a first region of reduced internal diameter receiving a sealing gasket therein, the sealing gasket being conically profiled when viewed in cross section having an inner extent and an outer extent, the bell end opening also having a second region of further reduced internal diameter which forms a circumferential shoulder region therein receiving a male spigot end of a mating pipe which is formed of the different material;

the adapter integral flange having a front face, a rear face and an outer peripheral surface, and wherein a rigid metal reinforcing ring is closely received upon and circumscribes the outer peripheral surface forming an outer sleeve thereon in order to strengthen the connection and prevent extrusion of the sealing gasket when the spigot end of a mating male pipe is inserted within the bell end opening of the adapter to form the pipe coupling, the first region of reduced internal diameter forming a sloping conical surface receiving the conically profiled sealing gasket, the outer extent of the sealing gasket being located approximately flush with the front face of the integral flange of the adapter; and

a mechanical restraint system which engages an external surface of the mating male pipe and the front and rear faces of the integral flange, respectively, in order to prevent the mating male pipe from pulling away from the bell end opening of the integral flange, the mechanical restraint system including a gland ring and a cooperating restraining gland which are connected by a series of cross bolts, whereby tightening the cross bolts causes force to be exerted on the mechanical restraint in order to compress the sealing gasket and prevent separation of the coupling, the restraining gland being provided with a series of circumferential holes which receive restraining screws, the screws having lower ends which bite into the external surface of the mating male pipe.

2. The pipe coupling of claim 1, wherein the length of pipe having the polyolefin wall is formed of polyethylene.

3. A pipe joint, comprising:

a first section of pipe having a polyolefin pipe wall and a second section of pipe of a different material;

an adapter formed of a length of pipe having a polyolefin pipe wall, the adapter having a fusing end which is fused to the first section of pipe, the adapter also having a coupling end;

wherein the coupling end of the adapter is joined to the fusing end by a nominal thickness pipe wall with an integral flange being formed on the coupling end thereof,

wherein the integral flange defines a bell end opening for the adapter, the bell end opening having a first region of reduced internal diameter for receiving a sealing gasket therein, the sealing gasket being conically profiled when viewed in cross section having an inner extent and an outer extent, the bell end opening also having a second region of further reduced internal diameter which forms a circumferential shoulder region therein for receiving a male spigot end of a mating pipe which is formed of the different material;

the adapter integral flange having a front face, a rear face and an outer peripheral surface, and wherein a rigid metal reinforcing ring is closely received upon and circumscribes the outer peripheral surface forming an outer sleeve thereon in order to strengthen the connection and prevent extrusion of the sealing gasket when the spigot end of a mating male pipe is inserted within the bell end opening of the adapter to form the pipe coupling, the first region of reduced internal diameter forming a sloping conical surface receiving the conically profiled sealing gasket, the outer extent of the sealing gasket being located approximately flush with the front face of the integral flange of the adapter;

the sealing gasket installed within the second region of reduced internal diameter of the integral flange;

a male spigot pipe end of the second section of pipe being inserted within the bell end opening and engaging the circumferential shoulder region thereof to thereby form a sealed pipe joint; and

a mechanical restraint system which engages an external surface of the second section of pipe of the different material and the front and rear faces of the integral flange, respectively, in order to prevent the second section of pipe from pulling away from the bell end opening of the integral flange, the mechanical restraint system including a gland ring and a cooperating restraining gland which are connected by a series of cross bolts, whereby tightening the cross bolts causes force to be exerted on the mechanical restraint in order to compress the sealing gasket and prevent separation of the coupling, the restraining gland being provided with a series of circumferential holes which receive restraining screws, the screws having lower ends which bite into the external surface of the second section of pipe.

4. The pipe joint of claim 3, wherein the length of pipe having the polyolefin wall is formed of polyethylene.

5. The pipe joint of claim 3, wherein the length of pipe of a different material is formed of a material selected from the group consisting of PVC, ductile iron, cast iron and steel.