Polyvinyl Chloride Formulations

• US 20120048417A1
• Filed: 10/10/2011
• Published: 03/01/2012
• Est. Priority Date: 06/13/2003
• Status: Active Grant

• Current Assignee: Underground Solutions, Inc. (Aegion Corp.)
• Original Assignee: Underground Solutions Technologies Group Inc. (Aegion Corp.)
• Inventors: Smith, Mark A., Marti, Thomas, St.Onge, Bryan, St.Onge, Henri
• Granted Patent: US 8,178,640 B2
• Time in Patent Office: Days
• US Class Current: 138/155
• CPC Class Codes: B29C 55/24 radial
• CPC Class Codes: B29C 63/34 using tubular layers or sheathings
• CPC Class Codes: B29C 65/02 by heating, with or without pressure
• CPC Class Codes: B29C 65/2015 being a single welding mirror comprising several separate heating surfaces in different planes, e.g. said heating surfaces having different temperatures
• CPC Class Codes: B29C 65/2061 by sliding
• CPC Class Codes: B29C 65/2092 and involving the use of a facer
• CPC Class Codes: B29C 65/7841 Holding or clamping means for handling purposes clamping means for the purpose of applying pressure on the parts to be joined, in the area to be joined B29C66/81; work holders in general B25B; devices for holding or positioning work for welding metal B23K37/04
• CPC Class Codes: B29C 65/8215 Tensile tests
• CPC Class Codes: B29C 65/8246 Pressure tests, e.g. hydrostatic pressure tests
• CPC Class Codes: B29C 66/022 Mechanical pre-treatments, e.g. reshaping
• CPC Class Codes: B29C 66/02241 Cutting, e.g. by using waterjets, or sawing using heat B29C66/0246; cutting-off or cutting-out a part of a strip-like or sheet-like material, transferring that part and fixing it to an article B29C69/005
• CPC Class Codes: B29C 66/02245 Abrading, e.g. grinding, sanding, sandblasting or scraping
• CPC Class Codes: B29C 66/1142 Single butt to butt joints
• CPC Class Codes: B29C 66/5221 for forming coaxial connections, i.e. the tubular articles to be joined forming a zero angle relative to each other
• 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 66/90 Measuring or controlling the joining process
• CPC Class Codes: B29C 66/91411 of the parts to be joined, e.g. the joining process taking the temperature of the parts to be joined into account
• CPC Class Codes: B29C 66/919 characterised by specific temperature, heat or thermal flux values or ranges specific electrical resistance values B29C66/81262
• CPC Class Codes: B29C 66/929 characterized by specific pressure, force, mechanical power or displacement values or ranges
• CPC Class Codes: B29C 66/949 characterised by specific time values or ranges
• CPC Class Codes: B29K 2027/06 : PVC, i.e. polyvinylchloride
• CPC Class Codes: B32B 1/08 : Tubular products
• CPC Class Codes: B32B 27/00 : Layered products comprising a layer of synthetic resin fibrous or filamentary layer made of a synthetic resin B32B5/02; particulate layer made of a synthetic resin B32B5/16; foamed layer made of a synthetic resin B32B5/18
• CPC Class Codes: C08K 13/02 : Organic and inorganic ingredients
• CPC Class Codes: C08L 27/06 : Homopolymers or copolymers of vinyl chloride
• CPC Class Codes: F16L 47/02 : Welded joints; Adhesive joints
• CPC Class Codes: F16L 55/1654 : and being inflated
• CPC Class Codes: F16L 55/1656 : materials for flexible liners hoses in general F16L11/00
• CPC Class Codes: F16L 9/22 : Pipes composed of a plurality of segments
• CPC Class Codes: Y10T 156/1016 : Transverse corrugating
• CPC Class Codes: Y10T 156/1043 : Subsequent to assembly
• CPC Class Codes: Y10T 428/1379 : Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
• CPC Class Codes: Y10T 428/139 : Open-ended, self-supporting conduit, cylinder, or tube-type article
• CPC Class Codes: Y10T 428/19 : Sheets or webs edge spliced or joined

Abstract

An extrudable polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride for use in extruding a first part and a second part, wherein a fusion joint between the first extruded part and the second extruded part is formed by: A) composition at least a portion of a first terminal edge of the first extruded part and a first terminal edge of the second extruded part; B) engaging the melted terminal edges; and C) maintaining pressure between the engaged terminal edges to create a fused joint having a strength that is at least 50% of the tensile strength of the extruded part as measured by ASTM D638-2a. The extruded parts can be pipe sections.

Claims

1. A method of fusing a first extruded part and a second extruded part, the method comprising the steps of:

melting a first terminal edge of the first extruded part and a second terminal edge of the second extruded part;

engaging the melted first terminal edge with the melted second terminal edge; and

maintaining pressure between the engaged terminal edges to create a fused joint between the first extruded part and the second extruded part,

wherein the first extruded part and the second extruded part are extruded from a polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride,

such that the fused joint exhibits a strength that is at least 50% of the tensile strength of the first extruded part or second extruded part, as measured by ASTM D638-2a.

2. The method of claim 1, wherein the polyvinyl chloride is virgin polyvinyl chloride.

3. The method of claim 1, wherein the polyvinyl chloride composition includes from 0.001 to 1.5 percent by weight of one or more heat stabilizers.

4. The method of claim 1, wherein the polyvinyl chloride composition includes from 0.1 to 5 percent by weight of one or more divalent metal salts of one or more C₆ to C₃₂ linear, branched or cyclic alkyl, alkenyl, aryl, aralkyl or alkaryl carboxylic acids.

5. The method of claim 4, wherein the divalent metal salts of carboxylic acids comprise calcium stearate.

6. The method of claim 1, wherein the polyvinyl chloride composition further includes from 0.1 to 5 percent by weight of one or more waxes.

7. The method of claim 6, wherein the waxes comprise one or both of a paraffin wax and a polyethylene wax.

8. The method of claim 1, wherein the polyvinyl chloride composition includes from 0.1 to 5 percent by weight of one or more fillers.

9. The method of claim 8, wherein the fillers are selected from the group consisting of pigments, clays, calcium carbonate, silica, carbon black and combinations thereof.

10. The method of claim 1, wherein the polyvinyl chloride composition includes from 0.1 to 5 percent by weight of one or more compounds capable of providing protection against ultraviolet (UV) radiation.

11. The method of claim 10, wherein the UV protecting compound comprises titanium dioxide.

12. The method of claim 1, wherein the polyvinyl chloride composition has a melting temperature of at least 125°

C.

13. The method of claim 1, wherein the interfacial pressure maintained between the engaged or contacted terminal edges is from 50 psi (344,750 Pa) to 200 psi (1,379,000 Pa).

14. The method of claim 1, wherein the first extruded part and the second extruded part is a section of pipe.

15. The method of claim 14, wherein the section of pipe is at least one of a pressure water pipe, a gravity drain sanitary pipe, a utility conduit, a pipe inserted in horizontal directional drilling, a pipe used in slip lining, a pipe used in pipe bursting application, a pipe used in guided boring, and a pipe used in direct bury applications or any combination thereof.

16. The method of claim 14, wherein the section of pipe has a diameter from 0.5 inch (1.25 cm) to 60 inches (153 cm).

17. The method of claim 14, wherein the section of pipe has a wall thickness of from 0.05 inch (0.125 cm) to 3 inches (7.6 cm).

18. The method of claim 14, further comprising the step of:

expanding the fused sections of pipe in an expansion operation;

wherein the tube diameter of the expanded pipe is from 1.05 to 3 times the pre-expanded tube diameter of the pre-expanded pipe; and

wherein the pressure rating of the expanded pipe is at least 50% of the pressure rating of the pre-expanded pipe, as measured according to ASTM D2241.

19. A fused joint produced in accordance with the method of claim 1.

20. A method of expanding at least one extruded pipe section, the method comprising the steps of:

providing a pipe section extruded from a polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride; and

expanding the extruded pipe section in an expansion operation, thereby forming an expanded pipe section having a tube diameter from 1.05 to 3 times the pre-expanded tube diameter,

wherein the pressure rating of the expanded pipe section is at least 50% of the pressure rating of the pre-expanded pipe section, as measured according to ASTM D2241.

21. The method of claim 20, further comprising the steps of:

expanding a first extruded pipe section and a second extruded pipe section according the method of claim 20; and

fusing the first extruded pipe section and the second extruded pipe section by;

(i) melting a first terminal edge of the first extruded pipe section and a second terminal edge of the second extruded pipe section;

(ii) engaging the melted first terminal edge with the melted second terminal edge; and

(iii) maintaining pressure between the engaged terminal edges to create a fused joint between the first extruded pipe section and the second extruded pipe section.

22. The method of claim 21, wherein the fused joint exhibits a strength that is at least 50% of the tensile strength of the first extruded pipe section or the second extruded pipe section, as measured by ASTM D638-2a.

23. An expanded pipe section produced in accordance with the method of claim 21.

24. A method of expanding a fused pipe formed from a first pipe section and a second pipe section, the method comprising the steps of:

extruding the first pipe section and the second pipe section from a polyvinyl chloride composition comprising from 80 to 99.9 percent by weight polyvinyl chloride;

melting a first terminal edge of the first extruded pipe section and a second terminal edge of the second extruded pipe section;

engaging the melted first terminal edge with the melted second terminal edge;

maintaining pressure between the engaged terminal edges to create a fused joint between the first extruded pipe section and the second extruded pipe section, thereby forming a fused pipe; and

expanding the fused pipe in an expansion operation, thereby forming an expanded, fused pipe.

25. The method of claim 24, wherein the fused joint exhibits a strength that is at least 50% of the tensile strength of the first pipe section or second pipe section, as measured by ASTM D638-2a.

26. The method of claim 24, wherein the tube diameter of the expanded pipe is from 1.05 to 3 times the tube diameter of the pre-expanded first pipe section or second pipe section.

27. The method of claim 24, wherein the pressure rating of the expanded pipe is at least 50% of the pressure rating of the pre-expanded first pipe section or second pipe section, as measured according to ASTM D2241.

28. An expanded, fused pipe produced in accordance with the method of claim 24.