Sweat flange, piping system and method of use

A sweat flange, piping system utilizing the same, and method of installing a circulator to a copper pipe. The sweat flange includes a base portion having a predetermined shape and at least two bolt openings dimensioned to accept at least two mounting bolts. A shoulder portion extends from the base portion and includes a substantially circular pipe opening that extends through the base portion and the shoulder portion. The pipe opening includes a first portion dimensioned to accept the pipe and a second portion of decreased diameter in order to limit the travel of the pipe through the opening. The sweat flange is attached to the pipe by inserting the pipe into the pipe opening of the flange and soldering the two together using art recognized soldering techniques. The piping system includes at least one pipe, a sweat, a pair of mounting bolts and a circulator or other pump. The piping system is assembled by inserting the pipe within the pipe opening in the sweat flange and soldering the pipe to the sweat flange. The pipe and the sweat flange are allowed to cool and the bolt openings of the sweat flange are aligned with the bolt openings of the volute flange. The mounting bolts are disposed through the bolt openings in pipe flange and the volute flange and are secured such that the sweat flange and the pump are secured together.

FIELD OF THE INVENTION
 The present invention relates to the field of plumbing and heating and, in
 particular, to a flange for connection to a water circulator or pump and
 to a piping system utilizing the same.
 BACKGROUND OF THE INVENTION
 Flanges are typically used to connect pumps or flow controlling devices to
 a pipe, or to connect a pipe to another pipe directly. Connections of this
 type are used extensively in the plumbing and heating industry, especially
 with steel, brass or copper pipes.
 A typical piping system includes a copper pipe, a copper adapter having a
 threaded portion, a pipe flange dimensioned to mate with the threaded
 portion of the copper adapter, and a circulator having a flange
 dimensioned to mate with pipe flange. The typical system is assembled
 together by first soldering the adapter to the copper pipe and allowing
 the pipe and adapter to cool. The pipe flange is subsequently threaded
 onto the threaded portion of the copper adapter by rotating the body of
 the flange using a large wrench. The circulator is disposed such that the
 flange is adjacent to the base portion of pipe flange and is secured to
 the pipe flange with bolts.
 The current system poses significant problems. First, the force required to
 attach the flange to the pipe is substantial and a typical flange will not
 have a shoulder that is designed to serve as a gripping surface for
 tightening the flange. The absence of this shoulder necessitates the use
 of a large pipe wrench to attach the flange to the exterior pipe threads
 of the copper adapter. As the surrounding free space is usually obstructed
 and quite small, it is often difficult for a user to maneuver the wrench.
 In addition, the size and shape of the gripping surface may also vary as
 the flange is turned onto the pipe, thus necessitating the use of more
 than one wrench. For these reasons, typical pipe flanges are well known as
 fittings that present a fastening problem.
 One particularly common problem is encountered when attaching pipe flanges
 to pipe ends for connection to circulators, such as those utilized in home
 heating systems. These flanges are typically elliptical in shape and do
 not readily accommodate a standard pipe wrench or other tightening device.
 In addition, when the elliptical ends of the flange have turned within the
 180 degrees tightening arc, the wrench must be readjusted, necessitating
 many fatiguing and time consuming iterations to complete the task.
 Moreover, as the size of a pipe wrench increases, the length of the handle
 increases proportionally. As pipe flanges must often be attached to a
 circulator that is extremely close to a wall, other pipes or, even worse,
 a corner, the use of a long handled pipe wrench or a pry-bar and long
 stove bolts to attach the flange to the pipe makes this job a tiring and
 time consuming one.
 One solution to this problem is disclosed in the inventor's U.S. patent
 application Ser. No. 08/897,741, now U.S. Pat. No. 5,839,331, titled
 FLANGE TIGHTENING TOOL. This application discloses a flange-tightening
 tool for use in securing a standard flange to a pipe. The tool has a base
 plate, a tightening hexagonal shoulder, two attachment openings, and a
 rotating handle perpendicular to the tightening base plate. The base plate
 and openings are dimensioned to mate with the flange to be tightened and
 the rotatable handle is attached to hexagonal shoulder and can be used to
 position the tool against the flange. In operation, the user positions the
 tool against the flange, attaches the tool to the flange by inserting
 bolts through the openings in the base plate, and attaches the flange to
 the pipe by gripping and rotating the hexagonal shoulder with an
 appropriately sized box or adjustable type wrench.
 The inventor's co-pending application has many advantages over the current
 flange tightening methods. It eliminates the gripping problems associated
 with standard pipe flanges by gripping the flange at the mating surface
 rather than the shoulder. In addition, box or adjustable wrenches having
 appropriately sized handles may be utilized rather than the long handles
 associated with larger sized pipe wrenches. Despite these advantages, this
 solution has not gained acceptance due to the cost of the tool and the
 reluctance of installers to adapt their methods to new technologies.
 Another problem inherent in prior art systems is the need to attach a
 separate threaded connector to the copper pipe in order to accommodate the
 threaded pipe flange. The use of such a connector adds to the material
 cost of the job, increases the time taken to assemble the system by adding
 a step to the process, and poses some danger to the copper piping system
 to which it is connected due to the rotational forces exerted upon the
 pipes through the attachment of the threaded flange. Although it is
 recognized that a copper adapter is not necessary in prior art systems
 utilizing steel or brass pipes, the predominant use of copper piping in
 new heating systems necessitates the use of such a connector in an
 increasing number of heating applications.
 Therefore, there is a need for a means for attaching a flange to a copper
 pipe that may be utilized to install the flange adjacent to an existing
 circulator or other flanged device, that may be assembled in close
 quarters without a large pipe wrench, and that eliminates the need for a
 threaded copper adapter.
 SUMMARY OF THE INVENTION
 The present invention is a sweat flange, a piping system utilizing the
 same, and a method of installing a circulator to a copper pipe. In its
 most basic form the sweat flange includes a base portion having a
 predetermined shape and at least two bolt openings dimensioned to accept
 at least two mounting bolts. A shoulder portion extends from the base
 portion and includes a substantially circular pipe opening that extends
 through the base portion and the shoulder portion. The pipe opening
 includes a first portion dimensioned to accept the pipe and a second
 portion of decreased diameter in order to limit the travel of the pipe
 through the opening. The sweat flange is attached to the pipe by inserting
 the pipe into the pipe opening of the flange and soldering the two
 together using art recognized soldering techniques. The preferred sweat
 flange is elliptical in shape and can be made of materials whose choice is
 determined by the nature of the piping system and the ability to solder
 the pipe and the flange. The preferred flange includes a thinned area
 around and between the shoulder portion and the openings in the base
 portion of the sweat flange for reducing the weight of the flange. In some
 embodiments, the base portion includes a recessed portion for accepting a
 circular gasket, while in other embodiments, the base portion includes a
 substantially flat bottom without any recess.
 In its most basic form, the piping system of the present invention includes
 at least one pipe, a sweat flange as described above, a pair of mounting
 bolts, and a circulator or other pump. The circulator is made up of a pump
 portion and a volute portion through which the fluid is pumped. The volute
 portion includes at least one volute flange that is dimensioned to mate
 with the sweat flange. In some embodiments, the volute flange includes a
 substantially flat mounting surface, while in others the mounting surface
 includes a recessed portion that is dimensioned to accept a gasket. The
 piping system is assembled by inserting the pipe within the pipe opening
 in the sweat flange and soldering the pipe to the sweat flange. The pipe
 and the sweat flange are allowed to cool and the bolt openings of the
 sweat flange are aligned with the bolt openings of the volute flange. The
 mounting bolts are disposed through the bolt openings in pipe flange and
 the volute flange and are secured such that the sweat flange and the pump
 are secured together. In the preferred system, a gasket is disposed be
 sweat flange and the volute flange.
 Therefore, it is an aspect of the invention to provide a sweat flange that
 may be utilized to install a flange adjacent to an existing circulator or
 other device.
 It is a further aspect of the invention to provide a sweat flange that may
 be easily installed in close quarters.
 It is a further aspect of the invention to provide a sweat flange that does
 not require a special tool to install and does not require installers to
 depart from accepted installation methods.
 It is a further aspect of the invention to provide a piping system in which
 a sweat flange may be easily attached to a circulator regardless of the
 location of the circulator in relation to walls, pipes or other devices.
 It is a still further aspect of the invention to provide a piping system
 that allows a flange to be attached to a copper pipe without the use of a
 separate threaded copper adapter.
 These aspects of the invention are not meant to be exclusive and other
 features, aspects, and advantages of the present invention will be readily
 apparent to those of ordinary skill in the art when read in conjunction
 with the following description, appended claims and accompanying drawings.

DETAILED DESCRIPTION OF THE DRAWINGS
 FIG. 1 is an exploded diagrammatic view of a prior art piping system using
 a typical flange that is secured to pipe ends by means of interior flange
 threads rotated to attach to the exterior pipe threads. The piping system
 50 includes a copper pipe 51, a copper adapter 52 having a threaded
 portion 53, a pipe flange 10 having an interior threaded portion
 dimensioned to mate with the threaded portion 53 of the copper adapter 52,
 a circulator 54, or other pump, having a volute flange 55 dimensioned to
 mate with pipe flange 10, mounting bolts 56, 57 and gasket 58.
 The typical system is assembled together in the arrangement shown in FIG.
 1. The copper adapter 52 is first soldered to the copper pipe 51 and
 allowed to cool. The pipe flange 10 is subsequently threaded onto the
 threaded portion 53 of the copper adapter by rotating the body of the
 flange 10 using a large wrench. The circulator 54 is disposed such that
 the volute flange 55 is adjacent to the base portion of pipe flange 10.
 Gasket 58 is then positioned between pipe flange 10 and volute flange 55
 and mounting bolts 56, 57 are passed through the openings in pipe flange
 10 and volute flange 55 and secured.
 Referring now to FIGS. 2A-2C, one embodiment of the sweat flange in
 accordance with the present invention is shown. The sweat flange 20 of the
 present invention is preferably manufactured of bronze, due to its
 solderability and relative durability. However, it is recognized that
 other solderable materials may be substituted to achieve similar results.
 In the embodiment of FIGS. 2A-2C, the sweat flange 20 includes a base
 portion 22 having an elliptical shape and least two openings 24, 26 that
 extend through the base portion 22. Each of the openings 24, 26 has a
 diameter that corresponds to the diameter of the mounting bolts (not
 shown) used to secure the sweat flange 20 to a mating flange. Shoulder
 portion 28 extends substantially perpendicularly from the base portion 22.
 An opening 30 extends through the base portion 22 and the shoulder portion
 28. Opening 30 has a predetermined diameter to correspond to the pipe (not
 shown) to which the sweat flange 20 is to be attached. As shown in FIGS.
 2B and 2C, opening 30 has a region of decreased dimension 34 along its
 height in order to limit the travel of the pipe to predetermined point.
 Referring now to FIG. 3, the preferred embodiment of the pipe flange 20 of
 the present invention is shown. As was the case with the embodiment of
 FIGS. 2A-2C, this embodiment includes an elliptical base portion 22 having
 two openings 24, 26. However, the preferred base portion 22 has a thinned
 area 32 in the space around and between the shoulder portion 28 and the
 openings 24, 26 to reduce the weight of the flange 20. This is preferred
 as the amount of energy required to heat the flange to the melting point
 of the solder is directly related to the mass of the flange being heated
 and the surface area of the flange that is exposed to the air. By reducing
 the mass of the flange, less energy is required and the flange may be
 heated more quickly than flanges having the same surface area but a larger
 mass. In addition, the reduction in the weight of the pipe flange 20 also
 reduces the per piece material and transportation costs associated with
 the each pipe flange 20.
 Referring now to FIG. 4, still another embodiment of the sweat flange 20 of
 the present invention is shown. This embodiment includes a shoulder
 portion 28 and a round base portion 22 that includes six openings 40-45,
 disposed substantially radially about the shoulder portion 28. Although
 this embodiment is shown as having a base portion 22 of substantially
 uniform cross section, it is recognized that the base portion may also
 include thinned portions in order to reduce the mass of the flange,
 allowing faster heating and reducing material and transportation costs.
 Referring next to FIG. 5, an exploded diagrammatic view of the piping
 system of the present invention that uses a sweat flange 20, such as those
 described with reference to FIGS. 2A-4. Piping system 50 includes a copper
 pipe 51, sweat flange 20, a circulator 54, or other pump, having a volute
 flange 55, mounting bolts 56, 57 and gasket 58. An installer would
 assemble the system in the arrangement shown in FIG. 5. The copper pipe 51
 and interior of the shoulder portion 28 of the sweat flange 20 are cleaned
 and fluxed. The copper pipe 51 is then inserted into the shoulder portion
 28 of the sweat flange 20 and the pipe 51 and flange 20 held together and
 heated, using a torch or other art recognized heating means, until the
 pipe 51 and flange 20 are at a temperature above the melting temperature
 of a solder to be utilized. The solder (not shown) is then applied about
 the junction of the shoulder portion 28 and pipe 51 using art recognized
 techniques and the pipe 51 and flange 20 are allowed to cool. Once the
 pipe 51 and flange 20 are sufficiently cooled, the circulator 54 is
 disposed such that the volute flange 55 is adjacent to the base portion 22
 of pipe flange 20. Gasket 58 is then positioned between pipe flange 20 and
 volute flange 55 and mounting bolts 56, 57 are passed through the openings
 in pipe flange 20 and volute flange 55 and secured.
 Gasket 58 may be a round gasket or may be shaped in the same configuration
 as the base portion 22 of the sweat flange 20. In the preferred
 embodiment, gasket 58 is manufactured from a hard rubber, but in other
 embodiments, gaskets manufactured from TEFLON.RTM., NEOPRENE.RTM., or cork
 may be utilized to achieve similar results.
 Circulator 54 may be any commonly used circulator or water pump. Circulator
 54 includes the pump, or cartridge, portion and a volute portion having at
 least one volute flange 55. In the preferred embodiment, circulator is an
 "00" series circulator manufactured by Taco, Inc. of Cranston, R.I. or a
 "Brute" series circulator manufactured by Grundfos, Inc. of Clovis, Calif.
 Referring now to FIGS. 6 & 7, bottom views of sweat flanges 20 having
 elliptical and circular base portions 22, are respectively shown. Base
 portions 22 have substantially flat bottoms 61 that are broken by the bolt
 openings, 56, 57 and 91-96, and openings 30. In these embodiments,
 substantially round recessed portions 62 are disposed about the openings
 30 to permit round gaskets (not shown) to be retained about the openings
 30. Recessed portions 62 are dimensioned to allow the gasket to be
 retained while still being able to be compressed during installation. It
 is recognized, however, that the recessed portion 62 is eliminated in
 other embodiments with both round and elliptically shaped gaskets being
 used. It is also recognized that the recessed portion 62 may be included
 in the volute flanges 55 rather than in the sweat flanges 20 of the
 present invention to achieve similar results.
 Although the present invention has been described in considerable detail
 with reference to certain preferred versions thereof, other versions would
 be readily apparent to those of ordinary skill in the art. Therefore, the
 spirit and scope of the appended claims should not be limited to the
 description of the preferred versions contained herein.