Chemical fusion of non-metallic pipe joints
View Patent ↗A pipe joint for joining pipes having a low surface energy and resistance to solvents. The components are an extrudable adhesive; a first pipe having a socket with an inside diameter, where the socket has a mouth, a self-centering bottom, and a cylindrical wall with an inlet, an outlet, and an inner annular channel; a second pipe having an insertion section with an end and an outer annular channel, where the second pipe has an outside diameter that is less than the inside diameter of the socket, the difference in diameters defining a gap and an interlocking keyway; and a flanged annular ring. The annular ring has an inside diameter that enables it to be slid over the second pipe and a thickness that is comparable to the gap. When the adhesive cures it forms a mechanical key. The adhesive is preferably an alkyl borane adhesive.
1. A pipe joint, said joint comprising:
an extrudable adhesive that solidifies on being extruded;
a first pipe having a socket with an inside diameter, where said socket has a mouth that is an open end of the socket, a self-centering bottom that is an opposing seating end of the socket, and a substantially cylindrical wall with an inlet, an outlet, and, an inner annular channel;
a second pipe having an insertion section with an end and an outer annular channel, where said insertion section of the second pipe is inserted into the socket of the first pipe, said second pipe having an outside diameter that is less than the inside diameter of the socket, where the difference in diameters defines a gap and where the outer annular channel of the second pipe lines up with the inner annular channel of the second pipe, the aligned channels defining an interlocking keyway filled with the extrudable adhesive;
a flanged annular ring, where said annular ring has an inside diameter that enables it to slide over the second pipe and a thickness that is comparable to the gap, and where the annular ring has a flange with a width that is sufficient to cap the mouth of the socket;
a temporary clamp that secures the insertion end, the socket and the flanged annular ring as the adhesive is extruded into the joint and until the adhesive has solidified; and
wherein, when said pipe joint is fully formed when the extrudable adhesive, after being injected into the joint substantially filling the gap and the interlocking keyway, solidifies, therein forming a mechanical key in the interlocking keyway.
2. The pipe joint, as claimed in claim 1 , wherein said inlet is in fluid communication with the interlocking keyway.
3. The pipe joint, as claimed in claim 2 , wherein said interlocking keyway serves to circumferentially distribute the extrudable adhesive around the joint.
4. The pipe joint, as claimed in claim 2 , wherein said outlet is in fluid communication with the gap at a point distal to the inlet.
5. The pipe joint, as claimed in claim 1 , wherein said interlocking keyway provides path for the extrudable adhesive to distribute circumferentially and flow longitudinally filling the gap and expelling entrained air.
6. The pipe joint, as claimed in claim 1 , wherein said joint has one or more additional interlocking keyways, where two or more outer channels are, aligned with two or more inner channels.
7. The pipe joint, as claimed in claim 1 , wherein said outer annular channel of the second pipe is cut into the insertion section using a router tool just prior to forming the joint.
8. The pipe joint, as claimed in claim 1 , wherein said pipe joint is comprised of an olefinic pipe material hiving a low surface energy and excellent resistance to solvents.
9. The pipe joint, as claimed in claim 8 , wherein the olefinic pipe material is selected from the group consisting of: HDPE, PEX, polypropylene and PTFE.
10. The pipe joint, as claimed in claim 1 , wherein the extrudable adhesive is. selected from the group consisting of: hot melt adhesives, cyanoacrylates adhesives, epoxy adhesives, urethane adhesives, alkyl borane adhesives, free radical and high solids adhesives.
11. The pipe joint, as claimed in claim 10 , wherein the extrudable adhesive is an alkyl borane two part adhesive.
12. The pipe joint, as claimed in claim 11 , wherein said alkyl borane adhesive is comprised of an organo borane in conjunction with acrylic oligomers, diluents, and monomers suitable for joining olefinic pipe.
13. The pipe joint, as claimed in claim 1 , wherein the adhesive is extruded using a mechanically actuated pump that can pump and mix one or more parts.
14. A coupling joint, said joint comprising:
an extrudable adhesive that solidifies on being extruded;
a first socket having an inside diameter, where said first socket has a first mouth that is an open end of the first socket, a self-centering bottom that is an opposing seating end of the first socket, and a substantially cylindrical wall with an inlet, an outlet, and an inner annular channel;
a second socket having an inside diameter, where said second socket has a second mouth that is an open end of the second socket, a second self-centering bottom that is an opposing seating end of the second socket, and a second substantially cylindrical wall with a second inlet, a second outlet, and a second inner annular channel;
wherein said first and second sockets are coupled end-to-end at an angle from 45 to 180 degrees;
a first pipe having a first insertion section with a first end and a first outer annular channel, where said first insertion section of the first pipe is inserted into the open end of the first socket, said pipe having an outside diameter that is less than the inside diameter of the first socket, where the difference in diameters defines a first gap and where the outer annular channel lines up with the inner annular channel therein forming a first interlocking keyway filled with the extrudable adhesive;
a second pipe having a second insertion section with a second end and a second outer annular channel, where said second insertion section of the second pipe is inserted into the second socket, said second pipe having a second outside diameter that is less than the inside diameter of the second socket, where the difference in diameters defines a second gap and where the second outer annular channel lines up with the second inner annular channel therein forming a second interlocking keyway filled with the extrudable adhesive;
a first flanged annular ring, where said first annular ring has a first inside diameter that enables it to slide over the first pipe and a first thickness that is comparable to the first gap, and where the first annular ring has a first flange has a first width that is sufficient to cap the first mouth of the first socket;
a second flanged annular ring, where said second annular ring has a second inside diameter that enables it to slide over the second pipe and a second thickness that is comparable to the second gap, and where the second annular ring has a second flange has a second width that is sufficient to cap the second mouth of the second socket;
a temporary clamp that secures the coupling joint while the extrudable adhesive is being extruded into the coupling joint and until the adhesive has solidified; and
wherein, said coupling joint is fully formed after the adhesive solidifies, therein forming, a first and second mechanical key in the first and second interlocking keyways.
15. The coupling joint, as claimed in claim 14 , wherein said first outlet is in fluid communication with the gap at a point distal to the first inlet, and said second outlet is in fluid communication with the gap at a point distal to the second inlet.
16. The pipe joint, as claimed in claim 14 , wherein said extrudable adhesive flows longitudinally from the interlocking keyway filling the gaps and expelling entrained air.