US 6,982,051 B2
Fusion process for conduit
Bryan St. Onge, Hastings (Canada); and Henri St. Onge, Hastings (Canada)
Assigned to Underground Solutions Technologies Group, Inc., Sarver, Pa. (US)
Filed on Feb. 26, 2004, as Appl. No. 10/788,921.
Claims priority of provisional application 60/478313, filed on Jun. 13, 2003.
Prior Publication US 2004/0251575 A1, Dec. 16, 2004
Int. Cl. B29C 37/02 (2006.01); B29C 65/02 (2006.01)
U.S. Cl. 264—40.1 17 Claims
OG exemplary drawing
 
1. A method for fusing a first conduit portion to a second conduit portion, comprising the steps of:
(a) removably positioning a first terminal edge of the first conduit portion in an opposing relationship with a first terminal edge of the second conduit portion;
(b) facing the first terminal edge of the first conduit portion and the first terminal edge of the second conduit portion;
(c) aligning the first terminal edge of the first conduit portion with the first terminal edge of the second conduit portion;
(d) melting at least a portion of the first terminal edge of the first conduit portion and the first terminal edge of the second conduit portion;
(e) engaging the melted terminal edge of the first conduit portion with the melted terminal edge of the second conduit portion; and
(f) maintaining pressure between the engaged terminal edge of the first conduit portion and the terminal edge of the second conduit portion, thereby creating a fused joint area;
wherein at least one of the first conduit portion and the second conduit portion comprises a polyvinyl chloride material, and
wherein the gauge pressure for the engaging step is calculated utilizing the following formula:
OG Complex Work Unit Drawing
wherein MGp is machine gauge pressure, π is 3.1416 circle formula, OD2 is outside diameter in inches squared, ID2 is inside diameter in inches squared, Ip is interfacial pressure and Ca is the cylinder area of machine in square inches.