Abstract:
A connection structure providing a sealed joint between first and second fluid conducting parts has a first seal surface on a first part, a second seal surface on a second part, and an annular elastomeric gasket positioned between the first and second seal surfaces. At least one of the first and second seal surfaces has at least one projection extending from a respective seal surface. The projection is adapted to pierce the elastomeric gasket and abut the opposing seal surfaces upon assembly of the first and second parts at relatively low, hand-tool torque levels.

Description:
FIELD OF THE INVENTION 
   The present invention relates to valves used in fluid conduit configurations to alternately shut off or allow fluid flow. 
   BACKGROUND OF THE INVENTION 
   Providing fluid flow through a conduit is a common requirement. In industrial applications, the flow of air, water or other fluids is often required in the operation of equipment. In residential settings, household plumbing is probably the most common example of fluid flow in a conduit. In these applications, it is often desirable to have the ability to control the flow of fluid at one or more points, through the use of shut-off valves. Such valves can be used simply as an outlet for the fluid, or to isolate downstream elements for such purposes as repair or maintenance. 
   The conduits to which a valve is to be connected will have a particular configuration defined by the conduit material, size, type of end connections, and arrangement. 
   Typical conduit materials include copper, plastic, rubber, steel, and composites. 
   The size of the conduit is generally specified by the inner diameter, but the outer diameter may also be important in certain connection types. 
   There are a wide variety of end connection types, including socket ends for soldering, male and female thread connections, compression fittings, barb fittings, flare connections, and many others. 
   The arrangement of the conduit refers to the number and orientation of the conduits to which the valve is to be connected. The arrangement may include a single conduit, at the end of which the valve is to be installed. Alternatively, the arrangement may include two coaxial conduits, requiring a straight valve, or two perpendicular conduits, requiring an angle valve. The arrangement could also consist of three conduits for which a “T” valve is required. 
   It is readily apparent that the number of unique conduit configurations is considerable. Stocking a comprehensive inventory of valves is therefore a difficult and costly task. For plumbers or pipefitters, it is generally cost prohibitive to carry a large inventory. Plumbers may have sources from which specific valves can be ordered, but receiving the valve is of course delayed by processing and delivery time. Alternatively, plumbers may have access to wholesale suppliers but such suppliers are not usually open in evenings or on weekends. As a result this may cause considerable delay and inconvenience. 
   The do-it-yourself homeowner will generally not stock any parts. Rather, he or she will typically rely on local hardware or home improvement retailers. These stores are usually open in evenings and on weekends, which is particularly convenient for the do-it-yourself homeowner. However, these retailers are also reluctant to incur the high cost of inventory associated with stocking ready-to-use valves in numerous variety, or to give up the large amount of shelf space which such a variety of valves would require. 
   It would be advantageous to have a kit of parts from which a valve could be assembled. Such a kit for assembling a valve is disclosed in U.S. Pat. No. 5,735,307 to Charron. The kit includes a valve body and end connectors which fit between the valve body and the conduits to which the valve is to be connected. 
   However, the valve assembled according to the &#39;307 patent is assembled in a production environment by the manufacturer. The manufacturer therefore achieves inventory cost reductions and convenience by following the teaching of the patent, but such benefits are not experienced by plumbers or do-it-yourself homeowners, or retailers on which they rely. 
   Furthermore, the kit of parts of the &#39;307 patent is adapted for assembly using industrial equipment and custom fixturing. It is critical that sufficient torque be applied when assembling the valve of the &#39;307 patent, particularly since tightening the connection fittings serves two purposes, namely, pre-loading the seals on the ball of the ball valve, and fixing the connection fittings to the valve housing. To satisfactorily pre-load the seals and to seal the brass-to-brass connection between the fitting and the valve body, a relatively high torque is required. This torque is easily reached with power fastening tools and fixtures designed to hold the valve body during tightening, without damaging the valve. However, since a user in the field cannot be expected to have specialized equipment for tightening of the connection fittings, offering the kit of parts of the &#39;307 patent to such a user is of no benefit 
   Furthermore, factory assembly of the parts of the &#39;307 patent permits leak testing of the valve open/close operation at the factory. Since the assembly of the valve core is completed by assembly of the connection fittings, providing the kit of parts of the &#39;307 patent to a user in the field would eliminate the ability to test the valve operation prior to final installation of the valve. 
   What is required is a kit of parts from which a valve for connection with any of a wide variety of conduit configurations can be assembled, using ordinary hand tools. The closure member of the valve should be sealed and assembled independatly of the connection fittings to permit factory assembly and leak-testing. 
   The above and other objects, features, and advantages of the present invention will be apparent in the following detailed description of the preferred embodiment thereof. 
   SUMMARY OF THE INVENTION 
   The present invention provides a kit of user-selectable parts from which a valve for connection with any of a wide variety of conduit configurations can be assembled, using ordinary hand tools. 
   In a first aspect of the invention, a kit of parts for field assembly of a shut-off valve with field selectable connection fittings is provided. The kit of parts includes a valve body, a plurality of connection fittings, and a plurality of gaskets. The valve body has a valve housing with three ports, wherein each of the ports has a longitudinal axis and a first connector end for receiving one of the connection fittings. The valve body has a valve closure member mounted within the valve housing, and a valve handle for moving the valve closure member between open and closed positions. The valve body has internal flow passageways for permitting the flow of fluid among said three ports through said valve closure member, and has a ball valve sealing structure to provide leak-proof operation of the valve closure member when moved between the open and closed positions. The ball valve sealing structure is assembled independent of the connection fittings received in the ports. 
   The first connector end of each of the ports has a first common configuration with a first seal surface. 
   Each of the plurality of connection fittings has a second connector end having a second common configuration with a second seal surface. Each of the plurality of connection fittings also has a different adaptor end. 
   The first connector ends of the ports are adapted to sealingly connect with the second connector ends of the plurality of connection fittings, using one of the plurality of gaskets, the gasket being positioned between the first and second seal surfaces of each of the ports and second connector ends. 
   In a second aspect of the invention, there is a gasket suitable for use with the kit of parts of the first aspect. The gasket is an annular disc of deformable metal having axially opposed first and second face surfaces and an inner diameter surface and outer diameter surface. The second face surface of the gasket is beveled relative to the second seal surface of the connection fitting such that the cross-sectional width of the gasket is wider at the inner diameter of the gasket and narrower at the outer diameter of the gasket. When a connection fitting is assembled finger tight into a port, the initial area of contact of the second face surface and the second seal surface is limited to a circle on the second face surface of the gasket located adjacent the inner diameter of the gasket. 
   The second aspect of the invention optionally includes provision for the first face surface of the gasket being beveled relative to the first seal surface. This is provided in one embodiment by beveling the first face surface of the gasket so that in cross section both the first and second face surfaces of the gasket taper inwardly from a widest point at the inner diameter to a narrowest point at the outer diameter of the gasket. Alternatively, this is provided by beveling the first seal surface of the first connector end of the port such that the first seal surface at its inner diameter is nearer to the outer end of the port than at its outer diameter. 
   The gasket may be of copper material or alternatively of aluminum material. 
   In a third aspect of the invention, there is an alternative gasket suitable for use with the kit of parts of the first aspect. The gasket is of an elastomeric material. The first seal surface of the port has at least one annular projection so that when tightening the connection fitting into the port, the elastomeric gasket is cut into at least two annular sections by the annular projection. The at least one annular projection makes metal-to-metal contact with the second seal surface, and at least one of the at least two annular sections of the elastomeric gasket is contained in a cavity bounded by the at least one annular projection, the first seal surface, and the second seal surface. 
   In an alternate embodiment of the third aspect of the invention, the first seal surface of the port has two concentric annular projections so that when tightening the connection fitting into the port, the elastomeric gasket is cut into three annular sections, namely an inner, middle, and outer annular section. The two annular projections make metal-to-metal contact with the second seal surface, and the middle annular section of the elastomeric gasket is contained in a cavity bounded radially by the two annular projections, and axially by the first seal surface and the second seal surface. 
   The elastomeric gasket of the third aspect of the invention is optionally of polytetrafluoroethylene (PTFE) material. 
   In a fourth aspect of the invention, a self-contained valve body for field assembly of a shut-off valve with field selectable connection fittings is provided. The valve body has a valve housing with a plurality of ports, each of the ports having a longitudinal axis and a first connector end for receiving a connection fitting. The valve body further has a valve closure member mounted within said the housing, a valve handle for moving the valve closure member between open and closed positions, and internal flow passageways for permitting the flow of fluid among the plurality of ports through the valve closure member. The valve body also has a ball valve sealing structure to provide leak-proof operation of the valve closure member when in, and moving between, the open and closed positions. The assembly and operation of the ball valve sealing structure is independent of the connection fittings received in the ports. 
   In a fifth aspect of the invention, a connection structure providing a sealed joint between first and second fluid conducting parts is described. The connection structure has a first seal surface on the first part, a second seal surface on the second part, and an annular elastomeric gasket positioned between the first and second seal surfaces. The first and second seal surfaces interact upon assembly of the first and second parts to provide an enclosed annular cavity which traps and is filled with at least a portion of the elastomeric gasket. 
   In a sixth aspect of the invention, a connection structure providing a sealed joint between first and second fluid conducting parts is described. The connection structure has a first seal surface on the first part, a second seal surface on the second part, and an annular gasket of deformable metal positioned between the first and second seal surfaces. The annular gasket has an inner diameter surface, an outer diameter surface, and axially opposed first and second face surfaces adjacent the first and second seal surfaces, respectively, and the first and second seal surfaces and first and second face surfaces define joint contact surfaces. At least one of the joint contact surfaces is beveled relative to the joint contact surface adjacent the beveled surface, so that the cross-sectional width of the gasket is wider at the inner diameter of the gasket. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a kit of parts according to one embodiment of the present invention with each of the parts shown in cross-section. 
       FIG. 2  shows one of the parts of the kit of  FIG. 1  in more detail. 
       FIG. 3  is a cross-sectional view of one of the components of the part shown in FIG.  2 . 
       FIG. 4  is a front view of another of the components of the part shown in FIG.  2 . 
       FIG. 5  is a side view of the component shown in FIG.  4 . 
       FIG. 6  is a front view in section of another of the components of the part shown in FIG.  2 . 
       FIG. 7  is a side view in section of the component shown in FIG.  6 . 
       FIG. 8  is a cross-sectional view of a portion of the part shown in  FIG. 2  in more detail. 
       FIG. 9  is an enlarged cross-sectional view of a portion of the part shown in FIG.  8 . 
       FIG. 10  is an enlarged cross-sectional view of another portion of the part shown in FIG.  8 . 
       FIG. 11  is a front view of a brass sealing ring intended for use with the kit of parts shown in FIG.  1 . 
       FIG. 12  is a side view in section of the brass ring shown in FIG.  10 . 
       FIG. 13  is a cross-sectional view of another portion of the part shown in  FIG. 2  in more detail. 
       FIG. 14  is a partial cross-sectional view of another of the parts shown in FIG.  1 . 
       FIG. 15  is a cross-sectional view of another of the parts shown in FIG.  1 . 
       FIG. 16  is a partial cross-sectional view of another of the parts shown in FIG.  1 . 
       FIG. 17  is a perspective view of a first gasket intended for use with the kit of parts shown in FIG.  1 . 
       FIG. 18  is a cross-section of the gasket of FIG.  17 . 
       FIG. 19  is a perspective view of an alternative gasket intended for use with the kit of parts shown in FIG.  1 . 
       FIG. 20  is a cross-section of the gasket of FIG.  19 . 
       FIG. 21  is a cross-sectional view of a portion of two parts of FIG.  1  and the gasket of  FIG. 17  shown in an assembled but pre-tightened state. 
       FIG. 22  is a cross-sectional view of a portion of two parts of FIG.  1  and the gasket of  FIG. 19  shown in an assembled but pre-tightened state. 
       FIG. 23  is a cross-section similar to  FIG. 22  but using an alternate form of one of the parts of FIG.  1 . 
       FIG. 24  is a perspective view of an alternative embodiment of a gasket intended to be used with the kit of parts shown in FIG.  1 . 
       FIG. 25  is a cross-sectional view of the gasket of FIG.  24 . 
       FIG. 26  is a cross-sectional view of a portion of two parts of the kit of FIG.  1  and the gasket of  FIG. 24  shown in an assembled but pre-tightened state. 
       FIG. 27  is a cross-sectional view similar to  FIG. 26  but showing parts in the tightened state. 
       FIG. 28  is a view similar to  FIG. 26  but showing parts of the kit of  FIG. 1  having an alternative sealing surface. 
       FIG. 29  is a cross-sectional view of the parts of  FIG. 28  but showing the parts in the tightened state. 
       FIG. 30  is a front view of the gasket of  FIG. 17  showing optional features. 
       FIG. 31  is a front view of the gasket of  FIG. 24  showing optional features. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   A kit of parts for assembly of a shut-off valve is shown generally at  10  in FIG.  1 . The kit of parts  10  comprises a valve body  12  and a plurality of connection fittings  14 . All connection fittings  14  have certain portions with a common configuration and certain portions with differing configurations. 
   Referring now to  FIG. 2 , valve body  12  comprises a valve housing  20  having a valve closure member  22 . Valve body  12  further comprises a spindle  24 , valve handle  26 , and three ports  28   a ,  28   b , and  28   c . The 3 ports have a common configuration and can accept any of the parts  14  of the kit of parts  10 . 
   As shown in  FIG. 3 , valve closure member  22  comprises a sphere  30  as is used in what is commonly known as a “ball valve”, but it is to be appreciated by one skilled in the art that any known valve closure member can be used to carry out the present invention. 
   Sphere  30  comprises three openings  32   a ,  32   b , and  32   c  leading to channels  34   a ,  34   b , and  34   c , respectively. Openings  32   a  and  32   b  are disposed 90° apart on the surface of sphere  30 , and opening  32   c  is disposed 180° and 90° from openings  32   a  and  32   b , respectively. The three channels  34   a ,  34   b , and  34   c  intersect at approximately the center of sphere  30 . An elongate slot  36  is provided in the surface of sphere  30  diametrically opposite opening  32   b.    
   As can best be seen in  FIGS. 4 and 5 , spindle  24  comprises a shaft  40  having a first cylindrical spindle portion  41  and a second rectangular spindle portion  42 . First cylindrical spindle portion  41  has a plurality of grooves  45  in which o-rings  46  are provided. A flange  47  is disposed between first cylindrical spindle portion  41  and a tab  44 . Tab  44  is adapted to engage slot  36  of sphere  30 , so that rotation of spindle  24  about its longitudinal axis causes corresponding rotation of sphere  30 . A plurality of barbs  48  are provided along second rectangular spindle portion  42  of shaft  40 , for attachment to valve handle  26 . 
   Valve body  12  further comprises valve handle  26  which can be actuated to effect the rotation of spindle  24 . As can be best seen in  FIGS. 6 and 7 , valve handle  26  comprises a valve lever  50  which has a rectangular cross-section and length suitable to be comfortably grasped by a user. Valve lever  50  has a first lever end  52  and a second lever end  54 . A rectangular bore  56  is provided in one longitudinal face  58  of valve lever  50 , axially positioned nearer to first lever end  52  then to second lever end  54 . Rectangular bore  56  is adapted to receive second rectangular spindle portion  42  of shaft  40  in a press-fit arrangement. 
   Referring again to  FIG. 2 , each of the ports  28   a ,  28   b , and  28   c  is characterized by a longitudinal bore having an axis  29   a ,  29   b , and  29   c  respectively, and extending inward from the outer surface  21  of valve housing  20  to valve closure member  22 . The three ports  28   a ,  28   b , and  28   c  are disposed  900  apart about valve closure member  22 , having port  28   b  aligned diametrically opposite spindle  24 , and ports  28   a  and  28   c  aligned opposite each other. This arrangement of the three ports  28   a ,  28   b , and  28   c  permits assembly of a straight valve, an angle valve, or a “T”-valve, as will be subsequently discussed. A cylindrical bore  27  is provided opposite port  28   b  and is adapted to sealingly receive first cylindrical portion  41  of shaft  40  of spindle  24 . 
   Referring now to  FIG. 8 , which shows a portion of valve body  12  in greater detail, each port  28  has an inner port end  60  nearest sphere  30  of valve closure member  22 , and an outer first connector end  61  nearest the outer surface  21  of valve housing  20 . 
   Inner port configurations  72  are provided at inner port ends  60  of each port  28 . Inner port configurations  72  need not be common among the three ports  28 . Each inner port configuration  72  comprises a port passageway  73  characterized by a longitudinal bore aligned coaxially with port  28 . Each inner port configuration further comprises a valve closure member sealing structure  74  disposed between port passageway  73  and sphere  30  of valve closure member  22 . Inner port configurations  72  provide flow passageways which are not more restricted than the passageways defined by the inner diameter of openings  32  in sphere  30  of valve closure member  22 . 
   Referring now to  FIG. 9 , sealing structure  74   a  is provided in port  28   a  and has an annular seal  76  of polytetrafluoroethylene (PTFE) material disposed between sphere  30  and an annular retaining lip  77 . Retaining lip  77  extends radially inward from the inner surface of port passageway  73   a , and has inner and outer axially opposed faces  78  and  79 , respectively. A substantial cylindrical seal seat  80  extends from inner face  78 , coaxial with port  28   a , having an inner diameter adapted to accommodate annular seal  76 . Seal seat  80  and port passageway  73   b  of port  28   b  intersect, so that a portion of seal seat  80  adjacent port  28   b  is cut away and therefore not visible in the sectional plane of FIG.  9 . The axial position of retaining lip  77  along port passageway  73   a  is such that annular seal  76  is held against the surface of sphere  30  once valve body  12  has been assembled, as will be discussed subsequently. 
   Referring now to  FIG. 10 , sealing structure  74   c  is provided at the inner end  60  of port  28   c . Sealing structure  74   c  comprises an annular seal  82  of PTFE material disposed between sphere  30  and a brass sealing ring  83 . As best seen in  FIGS. 11 and 12 , brass sealing ring  83  has inner and outer axially opposed faces  84  and  85 . The outer diameter surface of sealing ring  83  is stepped so that a first cylindrical portion  86  having a smaller outer diameter is adjacent inner face  84 , and a second cylindrical portion  87  having a larger outer diameter is adjacent outer face  85 . A chamfer  88  is provided at the corner of first cylindrical portion  86  and inner face  84 , to facilitate assembly of an o-ring  89  which is provided on first cylindrical portion  86 . 
   Referring again to  FIG. 10 , sealing structure  74   c  further comprises an internal retaining clip  90  which fits into an annular groove  92  provided in the inner surface of passageway  73   c . Annular groove  92  has a bevelled inner radial wall  93  so as to increase the axial width of groove  92  at the inner surface of port passageway  73   c  and thereby facilitate assembly of retaining clip  90 . Internal retaining clip  90  contacts the second face  85  of sealing ring  83  when assembled, and is provided at an axial position such that valve body  12  may be satisfactorily assembled using the following procedure. 
   Valve body  12  is assembled by first installing spindle  24  into valve housing  20 . Spindle  24  is installed by using port  28   b  for access, and inserting rectangular portion  42  of shaft  40  through cylindrical bore  27  of valve housing  20 . Spindle  24  is pushed through cylindrical bore  27  until flange  47  butts up against the inner end of cylindrical bore  27 . At this point valve handle  26  can be assembled by aligning bore  56  with rectangular portion  42  and pressing handle  26  on shaft  40  while holding shaft  40  in position relative to housing  20 . Tab  44  extending from shaft  40  is then aligned so the longitudinal axis of tab  44  is parallel to axes  29   a  and  29   c  of ports  28   a  and  28   c  respectively. 
   Next, annular seal  76  is seated in cylindrical seal seat  80  of retaining lip  77 , using port  28   c  for access. Sphere  30  is then installed through port  28   c , and is positioned against seal  80  ensuring that slot  36  of sphere  30  engages tab  44  of spindle  24 . Again using port  28   c  for access, annular seal  82  is then positioned against sphere  30  so that it surrounds opening  32   c . O-ring  89  is then positioned against annular seal  82 , and brass ring  83  is then inserted so that chamfer  88  of brass ring  83  contacts the inner diameter of o-ring  89 . Inner face  84  of brass ring  83  is then pressed through o-ring  89 , using chamfer  88  to guide o-ring  89  into position on first cylindrical portion  86  of brass ring  83 . The valve is then pre-loaded by pressing the outer face  85  of brass ring  83  axially towards retaining lip  77 , and locking the assembly in place by inserting internal retaining clip  90  into groove  92 . 
   This provides a fully functional pre-assembled valve body which is ready for use by a plumber, pipefitter, or do-it-yourself homeowner. Assembly of the valve body in a manufacturing environment enables the valve body to have the same level of quality associated with fully assembled ready-to-use valves, and yet offer the convenience of a user-configurable valve. The user need only select appropriate connection fittings  14  and install these fittings in the corresponding ports  28 . 
   Referring now to  FIG. 13 , each port  28  has an inner port end  60  nearest valve closure member  22 , and an outer first connector end  61  nearest the outer surface  21  of valve housing  20 . First connector end  61  of each port  28  has a first common configuration  62 , comprising a stepped bore having features along its length described below. 
   Nearest the outer surface  21  of valve housing  20 , first common configuration  62  comprises an internal clearance wall  64  extending parallel to and coaxial with the axis  29  of port  28 . Internal clearance wall  64  terminates at a first seal surface  66 , which extends radially inward from and substantially perpendicular to clearance wall  64 . Thread lead  68 , defined by a bevelled surface extending radially inward and axially towards inner port end  60 , is disposed about the entrance to an internally threaded bore  70 . 
   The plurality of connection fittings  14  will now be described. A representative sample of the connection fittings  14   a ,  14   b , and  14   c  is shown in  FIGS. 14 ,  15 , and  16 , respectively. Preferably the kit of parts  10  would comprise many more than three types of connection fittings, and many multiples of each type, but these three have been illustrated to serve as example. All such connection fittings  14  have a portion having a common configuration. This will be discussed in detail first. 
   Each connection fitting is elongate having an axis  96  and two axially opposed ends, namely a second connector end  98  and an adaptor end  99 . The second connector end  98  of each one of the plurality of connection fittings  14  has a second common configuration  100 , adapted to interact with first common configuration  62  of any one of ports  28  of valve housing  20 . The second common configuration  100  preferably comprises a first cylindrical portion  102  coaxial with axis  96 , having a male threaded portion  103  and an undercut portion  105 . Male threaded portion  103  mates with internal threaded portion  70  of first connector end  61 . Leading annular surface  104  is provided on one face of first cylindrical portion  102 , and is defined by an annular surface disposed perpindicular to and coaxial with axis  96 , extending radially inward from the outer diameter of first cylindrical portion  102  to an inner diameter which is not less than the diameter of opening  32  in sphere  30 . The combined axial length of male threaded portion  103  and undercut portion  105  is sized to permit assembly of connection fitting  14  in port  28 , as described in greater detail subsequently. 
   The second common configuration  100  further comprises a second cylindrical portion  106  coaxial with axis  96 , and adjacent to first cylindrical portion  102 , and axially opposite to leading annular surface  104 . Second cylindrical portion  106  has an outer diameter greater than that of first cylindrical portion  102 , but less than the internal diameter of clearance wall  64 . The radial surface at the transition in outer diameters between the first cylindrical portion  102  and second cylindrical portion  106  extends substantially perpindicular to axis  96  and defines a second seal surface  108 . 
   The adaptor ends  99  of the plurality of connection fittings  14  do not share a common configuration. Rather, any one adaptor end  99  has an adaptor configuration  110  which varies among the connection fittings  14 . Referring again to  FIGS. 14 ,  15 , and  16 , examples of specific adaptor configurations  110  include a female pipe adaptor configuration  14   a  (FIG.  14 ), a male barb adaptor configuration  14   b  (FIG.  15 ), and a plug configuration  14   c  (FIG.  16 ). Other adaptor configurations (not shown) include configurations for compression fittings, hose connections, flare connections, crimp connections, and threaded pipe connections and any other type of plumbing connection configuration. All of these configurations are well known in the art and may be included in the variety of adaptor configurations  110  provided on the adaptor ends  99  of the plurality of connection fittings  14 . 
   Preferably, any one adaptor configuration  110  is provided with parallel diametrically opposite lands  112  along the outer surface of adaptor end  99 . This enables adaptor end  99  to be gripped by a wrench. The parallel lands  112  may comprise a hexagon of sufficient width to accommodate the jaws of a wrench. The arrangement of and distance between the parallel lands  112  may vary between adaptor configurations  110 . 
   Each adaptor configuration  110  is also provided with a particular axial passageway  114 . However, in the case of an adaptor acting as a plug, the particular passageway  114  is blind so that the connector when used acts as a plug for a port  28 . The configuration of passageway  114  may differ among the various connection fittings  14  to meet the needs of the particular connection. The passageway  114  is the passageway for fluid but depending on the next component of the piping system, passageway  114  may also accept tubing, piping or other structure. The internal wall of axial passageway  114  may be adapted to fit an Allen key for turning, rather than providing lands  112  if desired, as shown in FIG.  16 . 
   Equipped with the kit of parts  10 , a user can select the particular connection fittings from the plurality of connection fittings  14  which have adaptor ends  99  with adaptor configurations  110  suitable for connection to the conduits between which the assembled shut-off valve is to be installed. 
   For example, assume that a shut off valve is required between a copper pipe and plastic hose disposed at 90° relative to each other. An angle valve having one female pipe connection and one barb connection is required. This can be assembled from the kit of parts  10  by selecting fitting  14   a  for port  28   a , fitting  14   b  for port  28   b , and fitting  14   c  for port  28   c.    
   Once the appropriate connection fittings  14   a ,  14   b , and  14   c  have been selected from the kit of parts  10 , each connection fitting  14   a ,  14   b , and  14   c  must be assembled to the corresponding ports  28   a ,  28   b , and  28   c . According to the present invention, this assembly should produce a leak-proof joint between each connection fitting  14  and each corresponding port  28 , using ordinary hand tools to support valve body  12  and tighten connection fitting  14 . 
   It was expected that a satisfactory joint could be assembled by using a gasket as is commonly practiced in the art. Gaskets for connection fittings are typically annular in shape, having axially opposed faces which are flat and perpendicular to the axis of the gasket. The gaskets are typically of an easily deformable metal, such as copper or aluminum, or of an elastomeric material such a polytetrafluorethylene (PTFE). 
   When attempting to use such a gasket in assembling the connection fittings  14  to the valve body  12  using ordinary hand tools, it was found that a leak-proof joint could not reliably be achieved. This appeared to be a result of imperfections in the second seal surface  108  of the connection fittings  14 , particularly at the outer circumference of second seal surface  108 . As seen in  FIG. 16 , these imperfections consist of nicks  133  caused by transporting or handling the plurality of connection fittings  14 , and/or raised imperfections  134  resulting from build-up during the plating process. Nicks  133  may leave gaps in the joint through which fluid can leak. Raised imperfections  134  tend to gouge and score adjacent gasket surfaces during tightening, leaving troughs through which fluid can leak. 
   In the present invention these problems have been overcome by using modified gaskets and seal surfaces as described below. 
   In a first embodiment the connection is made using a gasket  120 . Referring now to  FIG. 17 , gasket  120  comprises an annular disc of deformable metal such as copper or aluminum, having an axis  121 . The inner diameter surface  128  of gasket  120  is sized to fit over first cylindrical portion  102  of the connection fitting  14 . The outer diameter surface  126  of gasket  120  is sized to fit within clearance wall  64  of port  28 . As best seen in  FIG. 30 , the outer surface  126  of gasket  120  optionally comprises a plurality of radially outward extending projections  150  spaced equally about the circumference of outer surface  126 . The outer diameter  152  on which the radially outermost points of projections  150  lie is sized to provide a press-fit assembly of gasket  120  in clearance wall  64  of port  28 . This permits pre-assembly of gasket  120  in valve body  12 , thereby ensuring the, presence and concentric positioning of gasket  120  in port  28  during assembly of connection fitting  14 . 
   Referring again to  FIG. 17 , gasket  120  further comprises a first face surface  122  and a second face surface  124  axially opposed to one another. When the joint formed by connecting one of the plurality of the connection fittings  14  to one of the ports  28  is finger tight, first face surface  122  of gasket  120  is in contact with first seal surface  66  of valve housing  20 , and defines a first joint interface  130  (FIG.  21 ), and second face surface  124  of gasket  120  is in contact with second seal surface  108  of second connector end  98 , and defines a second joint interface  132 . This is best seen in FIG.  21 . 
   To achieve a desired seal in the embodiment of  FIG. 21 , the first and second face surfaces  122  and  124  of gasket  120  are bevelled, rather than perpendicular to the axis  121  of gasket  120 . This is best seen in FIG.  18 . The bevelled first and second face surfaces  122  and  124  are disposed such that the outer diameter surface  126  is narrower than the inner diameter surface  128  of gasket  120 , and the cross-sectional profile of gasket  120  is symmetrical about an axis  129  extending perpendicular to axis  121  through the center of the cross-section of gasket  120 . 
   As is best seen in  FIG. 21 , the pre-tightened first and second joint interfaces  130  and  132  have minimal contact surface area, approximating point contact when viewed in cross-section, or line contact when viewed axially. Furthermore, clearance is provided between second face surface  124  of gasket  120  and raised imperfections  134  extending from second seal surface  108 . 
   Upon application of a tightening torque to adaptor end  99  of the connection fitting  14 , connection fitting  14  advances axially and places an axial load on gasket  120 . This axial load causes deformation of gasket  120 , characterized by a flattening of bevelled first and second gasket faces  122  and  124  at the first and second joint interfaces  130  and  132 , so that the flattened portions of bevelled first and second gasket faces  122  and  124  lie in flush contact with first and second seal surfaces  66  and  108 . 
   On another embodiment of the gasket best seen in  FIGS. 19 ,  20 , and  22 , a gasket  220  is used to achieve a reduction in surface area of pre-tightened second joint interface  232  only, and to provide clearance between raised imperfections  134  and second gasket face surface  224 . First face surface  222  of gasket  220  is aligned perpendicular to axis  221  of gasket  220  so that first face surface  222  of gasket  220  sits flush against first seal surface  66  when the joint is pre-tightened. As a result, first joint interface  230 , defined by contact between first seal surface  66  and first face surface  222  of gasket  220 , has a surface area equal to the surface area of first face surface  222 . 
   As best seen in  FIG. 22 , bevelled second face surface  224  of gasket  220  provides a reduced contact surface area of second joint interface  232 , and clearance between raised imperfections  134  and second face surface  224 . 
   In yet another embodiment, best seen in  FIG. 23 , a modified seal surface  166  is provided on valve housing  20 . The first seal surface  166  is bevelled relative to first face surface  222  of gasket  220 , such that first seal surface  166  slopes deeper away from connection fitting  14  as surface  166  extends from its inner diameter to its outer diameter at clearance wall  164 . 
   In the pre-tightened state, a first joint interface  330  exists at the point of contact between the inner diameter of first seal surface  166  and first a face surface  222  of gasket  220 . A second joint interface  332  exists at the point of contact between the inner diameter of second face surface  224  of gasket  220  and second seal surface  108  of connection fitting  14 . 
   Upon tightening, deformation of gasket  220  at second joint interface  332  and clearance between raised imperfections  134  and second face surface  224  of gasket  220  is provided as in the previous embodiment. Deformation of gasket  220  at first joint interface takes the form of a pointed annular depression which mates with and surrounds first seal surface  166  and thread lead  168  in the vicinity where they meet at first joint interface  330 . In all these alternatives, contact with the imperfections  164  and resultant damage to the seal is reduced. Because of the minimal area of contact at at least one joint interface, hand tool torque is sufficient to deform the gasket to make a satisfactory seal, while using a deformable metal gasket. 
   In other applications it may be desirable to exploit the sealing properties of an elastomeric gasket, such as polytetrafluoroethyene (PTFE). Such gaskets are known to provide sealed joints with excellent initial leak-proof properties, but the elastomeric material tends to creep under load which in turn allows the joint to loosen over time, causing leaks. 
   We have discovered this problem may be overcome by providing a sealing structure which pierces the elastomeric gasket to capture at least a portion of the elastomeric material within an enclosed cavity created by assembly of the joint. With the elastomeric material enclosed within and filling the cavity the material cannot creep. 
   An elastomeric gasket  420  is shown in FIG.  24 . Gasket  420  is an annular disc of elastomeric material, disposed about axis  421 . Referring to  FIGS. 24 and 25 , the gasket  420  has a rectangular profile in cross-section, having a first face surface  422  and an axially opposed second face surface  424 , such that face surfaces  422  and  424  are parallel to each other and perpendicular to axis  421 . Gasket  420  further comprises an inner diameter surface  428  and outer diameter surface  426 . Referring now to  FIG. 31 , inner diameter surface  428  has a diameter  458  greater than the outer diameter of threaded portion  103  of the connection fitting  14 . Outer diameter surface  426  has a diameter  456  less than the diameter of clearance wall  64  of first common configuration  62  of the ports  28 . As best seen in  FIG. 31 , the inner diameter surface  428  of gasket  420  optionally comprises a plurality of radially inward extending projections  450  spaced equally about the circumference of inner diameter surface  428 . The inner diameter  452  on which the radially innermost points of radial projections  450  lie is sized to be smaller than the outer diameter of male threaded portion  103  of connection fitting  14 , but larger than the outer diameter of undercut portion  105 . This permits pre-assembly of gasket  420  on to connection fitting  14  by pushing gasket  420  over and past male threaded portion  103  onto undercut portion  105 , thereby ensuring the presence and concentric positioning of gasket  420  in port  28  during assembly of connection fitting  14 . 
   In a first embodiment, using gasket  420 , first seal surface  66  of port  28  is modified to have concentric annular axial projections  265  and  267 , as seen in FIG.  26 . Radially inner annular projection  265  comprises an annular ring of triangular cross-section extending from first seal surface  66 , disposed coaxially with axis  29  of port  28 , at a diameter slightly greater than the inner diameter of gasket  420 . The height of inner annular projection  265  is approximately equal to the thickness of gasket  420 . Radially outer annular projection  267  is similar to inner annular projection  265  but is provided at a radial point along first seal surface  66  which is between inner annular projection  265  and the outer diameter of gasket  420 . 
   In the pre-tightened state shown in  FIG. 26 , gasket  420  will be in contact with the peak of at least one of the inner and outer annular projections  265  and  267  on the first face surface  422  of gasket  420 , and raised imperfections  134  on the second face surface  424  of gasket  420 . 
   Upon tightening the joint as shown in  FIG. 27 , the peaks of the inner and outer annular projections  265  and  267  pierce gasket  420  and eventually come into metal-to-metal contact with second seal surface  108 . Some deformation of the peaks of annular projections  265  and  267  may occur. Any such deformation contributes to the sealing effect of the joint, and the metal-to-metal contact reduces susceptibility to undesired loosening. In addition, a central annular portion  442  of gasket  420  is captured between facing sides of annular projections  265  and  267 , first seal surface  66 , and second seal surface  108 . This elastomeric material is surrounded on all sides and fills the space. Thus, even though the portion  442  of elastomeric material is in compression it cannot creep as it is confined by the metal-to-metal contact. Radially outer portion  446  of gasket  420  acts as a further seal. 
   Radially inner portion  444  of gasket  420  is at least partially confined by thread lead surface  68 , undercut portion  105 , and second seal surface  108 . Thread lead  68  and undercut portion  105  are sized to provide a cavity sufficient to accommodate the volume of radially inner portion  444  of gasket  420 . However, some clearance is required between the mating male threads  103  and female threads  70 , and as a result some creep may occur. For this reason, radially inner portion  444  of gasket  420  may serve as a further seal but is not relied upon. 
   In another embodiment of the present invention employing elastomeric gasket  420 , a single annular projection  369  is provided on a modified seal surface  66 . Referring to  FIG. 28 , annular projection  369  has a triangular cross-section, with a height approximately equal to the thickness of gasket  420 . Annular projection  369  is disposed coaxially with axis  29  of the port  28 , at a radial position near the midpoint of the inner and outer diameters of first seal surface  66 . 
   In the pre-tightened state (FIG.  28 ), the first face surface  422  of gasket  420  is in contact with the peak of annular projection  369 , and the second face surface  424  of gasket  420  is in contact with raised imperfections  134 . 
   Upon tightening the joint (FIG.  29 ), the peak of annular projection  369  pierces gasket  420 , and eventually comes into metal to metal contact with second seal surface  108 . This structure provides a seal and protects against loosening of the joint over time, as in the previous embodiment. Furthermore, the outer annular portion  542  of gasket  420  is captured in a cavity bounded by the outer side face of annular projection  369 , first seal surface  66 , second seal surface  108 , and the close fit between clearance wall  64  and the outer diameter of second cylindrical portion  106 . As discussed above, the portion  542  of the gasket  420  is confined on all sides similar to portion  442  and therefore cannot creep which provides a satisfactory seal. As with the previous embodiment the torque available from hand operated tools is sufficient to pierce the gasket  420  and continue to move the connector  14  into the valve housing  20  until metal to metal contact occurs. 
   While preferred embodiments of the invention have been described herein in detail, it is to be understood that this description is by way of example only, and is not intended to be limiting. The full scope of the invention is to be determined from reference to the appended claims.