WO2002035142A2

WO2002035142A2 - Steam trap with shortened valve seat orifice

Info

Publication number: WO2002035142A2
Application number: PCT/US2001/048045
Authority: WO
Inventors: David W. Fischer
Original assignee: Armstrong International, Inc.
Priority date: 2000-10-27
Filing date: 2001-10-26
Publication date: 2002-05-02
Also published as: AU3519202A

Abstract

A steam trap having a casing forming a chamber. The steam trap includes inlet and outlet fittings, mounted on the casing, and adapted for fluid inflow into and outflow from the chamber, respectively. The steam trap also includes a valve seat. The valve seat includes a contact surface defining a valve opening. The valve seat further includes a passageway that provides fluid communication from the valve opening to the outlet fitting. The passageway includes a wide section and a narrow section. The narrow section is positioned between the valve opening and the wide section. The ratio of the width of the narrow section to the height of the narrow section is greater than about 2:1. The steam trap also includes a valve member movably disposed in the chamber and adapted to be moved into and out of sealing engagement with the contact surface of the valve seat to open and close the valve opening. The steam trap also includes an operating lever disposed in the chamber and operatively connected to the valve member to vertically apply force to effect movement of the valve member toward and away from the contact surface of the valve seat thereby closing and opening the valve opening. The steam trap also includes a vertically movable inverted bucket provided in the chamber and operatively connected to the operating lever. Vertical movement of the inverted bucket in the chamber will effect movement of the operating lever thereby to move the valve member into and out of sealing engagement with the valve seat.

Description

STEAM TRAP WITH SHORTENED VALVE SEAT ORIFICE

Inventor: David W. Fischer

TECHNICAL FIELD This invention relates to a method of removing condensate from steam. More specifically, this invention relates to an improved steam trap.

BACKGROUND OF TFIE INVENTION

The use of steam traps to remove condensate from steam is well known. An example of a steam trap is disclosed in U.S. Patent No. 4,149,557 to Keech et. al. and is incorporated herein by reference. In many steam supply systems, steam is provided to a desired location from a steam boiler that contains water being heated to steam therein. The steam is transported from the steam boiler in steam pipes or other conduits. The steam pipes can be formed of alloys such as, for example, copper or other metals. The water being converted to steam is often conditioned with chemicals. For example, various amines are added to the water used in steam applications to prevent corrosion of metallic structures, such as tubing. When the water is heated into steam and transported through tubing, such as copper tubing, the amine chemicals in the steam interact with the tubing. This interaction dissolves some of the metal, such as copper, from the tubing, resulting, in the presence of copper compounds and other metallic compounds in the steam.

A steam trap is generally used to remove condensate, or excess water, from the steam, The steam geiierally cools and loses pressure as it travels through the tubing, and as it passes through the steam trap. As a result_,, the metallic compounds and other contaminants in the condensate from the steam can "plate out" onto portions of Hie steam trap. This "plating out" results in undesirable deposits on structures of the steam trap.

Deposits in the steam trap can cause significant economic and logistical problems. The deposits restrict the flow of condensate through the steam trap, and may ultimately prevent the flow. This can result in excessive amounts of water being delivered along with the steam. As a remedy, the steam trap can be disassembled and cleaned or have elements inside the steam trap replaced. This remedy is costly and time consuming. Likewise, since the steam trap may be fixed into a steam line, removal of the steam trap may require the steam line to be cut, thus disrupting delivery of steam to the desired location.

It is often desirable to remove condensate from the steam by the use of the steam trap placed in one or more appropriate locations between the steam boiler and the location to receive the steam. When the condensate is separated from steam in the steam trap, portions of the steam trap can become fouled by the chemicals in the condensate removed from the steam. It would thus be desirable to provide a steam trap that is less susceptible to the adverse affects of the chemicals in the condensate.

SUMMARY OF THE INVENTION The above objects as well as other objects not specifically enumerated are achieved by an inverted bucket steam trap. The steam trap has a casing forming a chamber. The steam trap includes inlet and outlet fittings, mounted on the casing, and adapted for fluid inflow into and outflow from the chamber, respectively. The steam trap also includes a valve seat. The valve seat includes a contact surface defining a valve opening. The valve seat further includes a passageway that provides fluid communication from the valve opening to the outlet fitting. The passageway includes a wide section and a narrow section. The narrow section is positioned between the valve opening and the wide section. The ratio of the width of the narrow section to the i height of the narrow section is greater than about 2: 1. The steam trap also includes a valve member movably disposed in the chamber and adapted to be moved into and out of sealing engagement with the contact surface of the valve seat to open and close the valve opening. The steam trap also includes an operating lever disposed in the chamber and operatively connected to the valve member to vertically apply force to effect movement of the valve member toward and away from the contact surface of the valve seat, thereby closing and opening the valve opening. The steam trap also includes a vertically movable inverted bucket provided in the chamber and operatively connected to the operating lever. Vertical movement of the inverted bucket in the chamber will effect movement of the operating lever thereby to move the valve member into and out of sealing engagement with the valve seat.

According to this invention there is also provided an inverted bucket steam trap. The steam trap has a casing forming a chamber. The steam trap has inlet and outlet fittings, mounted on the casing, and adapted for fluid inflow into and outflow from the chamber, respectively. The steam trap has a valve seat. The valve seat includes a contact surface defining a valve opening. The valve seat further includes a passageway that provides fluid communication from the valve opening to the outlet fitting. The passageway includes a wide section and a narrow section, the narrow section being positioned between the valve opening and the wide section. The narrow section of the passageway is cylindrical. The ratio of the width of the narrow section to the height of the narrow section is greater than about 3: 1. The valve seat further includes a valve member movably disposed in the chamber and adapted to be moved into and out of sealing engagement with the contact surface of the valve seat to open and close the valve opening. The valve seat further includes an operating lever disposed in the chamber and operatively connected to the valve member to vertically apply force to effect movement of the valve member toward and away from the contact surface of the valve seat, thereby closing and opening the valve opening. The valve seat further includes a vertically movable inverted bucket provided in the chamber and operatively connected to the operating lever. Vertical movement of the inverted bucket in the chamber will effect movement of the operating lever thereby to move the valve member into and out of sealing engagement with the valve seat. Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view in elevation of a steam trap according to the invention.

Figure 2 is a cross-sectional view in elevation of a portion of the steam trap of Figure 1 taken along line 2-2 of Figure 1.

Figure 3 is a cross-sectional view in elevation of a portion of a prior art steam trap.

Figure 4 is a cross-sectional view in elevation, similar to Figure 2, of an alternate embodiment of the invention .

Figure 5 is a cross-sectional view in elevation, similar to Figure 2, of another alternate embodiment of the invention. Figure 6 is a Gross-sectional view in elevation, similar to Figure 2, showing a portion of the valve seat in greater detail.

Figure 7 is a cross-sectional view in elevation, similar to Figure 3. showing a portion of the prior art valve seat in greater detail.

Figure 8 is a cross-seGtional view in elevation, similar to Figure 5, showing the vertical wall of the valve seat in greater detail.

Figure 9 is a cross-sectional view in elevation, similar to Figure 8, showing an alternate embodiment of the vertical wall of the valve seat. DETAILED DESCRIPTION OF THE INVENTION As shown in Figure 1, a steam trap 10 includes a casing 12. The casing 12 is preferably formed of a lower casing section 14 and an upper casing section 16. The lower casing section 14 has a generally cylindrical wall 18 which is preferably open at an upper end 20 and closed at a lower end 22. The upper casing section 16 also has a generally cylindrical wall 24 which is preferably closed at its upper end 26 and opened at its lower end 28. The lower end 28 of the upper casing section 16 is coupled with the upper end 20 of the lower casing section 14 to form a chamber 30 therebetween. In a preferred embodiment, an inlet fitting 32 is provided in the casing 12, preferably in the upper casing section 16 thereof, for fluid flow downstream into the chamber 30. Similarly, an outlet fitting 34 is provided in the casing 12, preferably in the upper casing section 16 thereof, for fluid flow downstream out of the chamber 30. In a preferred embodiment, the outlet fitting 34 is provided on an opposing portion of the casing 12 from the inlet fitting 32, but may also be provided on a portion adjacent to the inlet fitting 32. In a preferred embodiment, the inlet fitting 32 and the outlet fitting 34 may be provided with internal threads (not shown) so that they can be connected to a portion of metallic tubing (not shown), carrying steam and condensate. The inlet fitting 32 and the outlet fitting 34 may be secured to the casing 12 at an appropriate location in any suitable manner, such as with a weld 36.

The inlet fitting 32 and the outlet fitting 34 are preferably supported in opposing ends of an elongated block-shaped fitting housing 33. The fitting housing 33 is preferably a generally straight-sided portion made of a suitable material for receiving one or more holes therein. The fitting housing 33 preferably has a hole 38 formed in a lower portion therein near the inlet fitting 32 to receive a downwardly extending J-tube 40. The upper end of the J-tube 40 is operatively connected to the inlet fitting 32 for fluid communication therewith. The J-tube 40 receives steam and condensate from the inlet fitting 32. The J-tube 40 is preferably disposed completely within the casing 12. The J-tube 40 is preferably positioned inward of the cylindrical wall 18 and is provided with an inwardly directed curved portion 42 near the lower end 22 of the lower casing section 14.

The curved portion 42 of the J-tube 40 includes a lower opening 44. The lower opening 44 is received by a lower end 46 of an inverted bucket 48. The inverted bucket 48 is preferably approximately cylindrical. The lower end 46 of the inverted bucket 48 is preferably opened. The inverted bucket 48 includes a vertical wall 50 which terminates at a top wall 52. The top wall 52 is preferably a flat plate, approximately annular and formed to the contour of the vertical wall 50. The inverted bucket 48 can also include a recess 54 in a portion of the vertical wall 50 to accommodate the downwardly extending J-tube 40. The top wall 52 of the inverted bucket 48 preferably has a hole 56 to allow steam 58 in the inverted bucket 48 to slowly escape therefrom. During operation of the steam trap 10, steam 58 and condensate 60 enter the lower end 46 of the inverted bucket 48 through the J-tube 40 connected to the inlet fitting 32. The steam 58 rises to the top wall 52 of the inverted bucket 48 and provides buoyancy to the inverted bucket 48 in the presence of a sufficient quantity of condensate 60 in the chamber 30. In the presence of sufficient buoyancy, the inverted bucket 48 rises in the chamber 30, or moves vertically toward the fitting housing 33. The inverted bucket 48 loses buoyancy and sinks in the chamber 30, or moves down vertically away from the fitting housing 33, when sufficient steam 58 escapes from the hole 56. The inverted bucket 48 is preferably operatively connected to an operating lever 62 by a connector 63. The connector 63 is preferably fixed to the top wall 52 of the inverted bucket 48. The connector 63 preferably does not obstruct the escape of steam 58 from the hole 56. The connector 63 preferably includes an upwardly extending hook 64 to engage the operating lever 62. The inverted bucket 48 may be connected to the operating lever 62 by any other suitable means, such as a plate, pin, screw, or other suitable sinkable linkage. Vertical movement of the inverted bucket 48 in the chamber 30 will effect movement of the operating lever 62.

Referring now to Figure 2, the operating lever 62 supports a preferably rounded valve member 66. The valve member 66 is preferably fixed to the operating lever 62 by a holder 67 near a secured end 68 of the operating lever 62. The valve member 66 may be attached to the operating lever 62 by any suitable fastener or may be fixed thereto by any suitable means, such as welding. The secured end 68 of the operating lever 62 is preferably movably connected to the fitting housing 33 by one or more downwardly extending hooks (not shown).

A valve seat 74 is preferably threaded to be received by a recessed portion 72 of the fitting housing 33. The recessed portion 72 is likewise preferably threaded for engagement of the valve seat 74. A valve seat 74 defines a passageway 96 that provides fluid communication from the chamber 30 to the outlet fitting 34. The valve seat 74 is adapted to receive the valve member 66 to control the flow of condensate 60 through the passageway 96. The valve seat 74 also preferably includes a narrow section 76, a contact surface 82 defining a valve opening 80, and a wide section 90. The narrow section 76 is preferably a single cylindrical conduit having a vertical wall 78. The narrow section 76 has a height HI and a width Wl . In a preferred embodiment, the ratio of the width W I of the narrow section 76 to the height HI of the narrow section 76 is greater than about 2:1. The narrow section 76 of the valve seat 74 is in fluid communication with the chamber 30 through a valve opening 80 in the contact surface 82. The valve opening 80 is preferably circular.

The condensate 60 in the narrow section 76 of the valve seat 74 continues through the passageway 96 into the wide section 90 of the valve seat 74. The wide section 90 has a width W2. The width W2 is greater than the width Wl of the narrow section 76. The wide section 90 preferably includes a single annular conduit 92 and a flared section 94. The flared section 94 is in fluid communication with the narrow section 76. It should be understood that the wide section 90 may include more than one conduit.

The passageway 96 allows for fluid communication between the chamber 30 and the outlet fitting 34 (shown in Figure 1). More specifically, the flow of condensate 60 through the passageway 96 travels from the valve opening 80 through the narrow section 76, the downstream wide section 90, and preferably through a generally transverse conduit 98 (shown in Figure 1) to the outlet fitting 34. The 98 is part of the transverse conduit 98 is part of the passageway 96.

Condensate 60 in the chamber 30 enters the narrow section 76 of the valve seat 74 when the valve member 66 is not in sealing engagement with the contact surface 82 at the valve opening 80. The valve member 66 is adapted for sealing engagement with the contact surface 82 of the valve seat 74 to open and close the valve opening 80. As the inverted bucket 48 in the chamber 30 fills with condensate 60 from the J-tube 40 and loses steam 58, the inverted bucket 48 loses buoyancy and moves downwardly, thus moving the operating lever 62 and the valve member 66. Movement of the valve member 66 controls the flow of condensate 60 through the passageway 96. Referring now to Figure 3, a prior art valve seat 174 is shown. The valve seat

174 includes a narrow section 176 having a vertical wall 178. The narrow section 176 has a height H2 and a width 3. It will be appreciated that the height H2 of the narrow section 176 is greater than the height HI of the narrow section 76 shown in Figure 2. The narrow section 176 of the valve seat 174 is in fluid communication with the chamber 30 through an opening 180 in a contact surface 182.

As shown in Figure 7, the condensate 60 in the chamber 30 enters the narrow section 176 in a flow path 184. It should be noted that the height H2 and the width W3 of the narrow section 176 are such that contact of the vertical wall 178 by the flow path 184 is not minimized. Indeed, the flow path 184 contacts the vertical wall 178, thereby forming mineral deposits 199 thereon. The mineral deposits 199 reduce the width W3 of the narrow section 176. As the amount of the mineral deposits 199 increases, the flow path 184 through the narrow section 176 is restricted. The mineral deposits 199 can eventually accumulate to the extent that they obstruct flow of the condensate 60 from the chamber 30. For the valve seat 174 shown, the ratio of the width W3 of the narrow section 176 to the height H2 of the narrow section 176 is about 1 : 1, which is less than 2:1. The condensate 60 in the narrow section 176 of the valve seat 174 continues downstream in the flow path 184 into a wide section 190 of the valve seat 174. The wide section 190 has a width W4. The width W4 is greater than the width W3 of the narrow section 176. The wide section 190 preferably includes a single circular conduit 192 and a flared section 194. The flared section 194 is in fluid communication with the narrow section 176. It should be understood that the wide section 190 may include more than one conduit. The valve seat 174 includes a passageway 196. The passageway 196 preferably includes the flow path 184 from the opening 180 through the narrow section 176, the downstream wide section 190, and the outlet fitting 34 (shown in Figure 1). Referring now to Figures 2 and 6, condensate 60 in the chamber 30 enters the narrow section 76 in a flow path 84. It should be noted that the height FI1 and the width W l of the narrow section 76 are such that contact of the vertical wall 78 by the flow path 84 is minimized. Therefore mineral deposits, of the type shown in Figure 3, on the vertical wall 78 from the metallic compounds in the condensate 60 passing through the narrow section 76 are minimized. In a preferred embodiment, contact of the vertical wall 78 by the flow path 84 is eliminated, thereby eliminating the mineral deposits of the type shown in Figure 3. Therefore it can be seen that condensate 60 flows into the passageway 96 of the valve seat 74 through the valve opening 80 in the contact surface 82, through the narrow section 96 and into the wide section 90.

Referring now to Figure 4, an alternate embodiment of a valve seat 274 is shown. The valve seat 274 defines a passageway 296 that provides fluid communication from the chamber 30 to the outlet fitting 234. The valve seat 274 is adapted to receive the valve member 66 to control the flow of condensate 60 through the passageway 296. The valve seat 274 also preferably includes a narrow section 276, a contact surface 282 defining a valve opening 280, and a wide section 290. The narrow section 276 is preferably a single cylindrical conduit having a vertical wall 278. The narrow section 276 has a height H4 and a width W5. The ratio of the width W5 of the narrow section 276 to the height H4 of the narrow section 276 is greater than about 2:1.

The condensate 60 in the chamber 30 enters the narrow section 276 of the passageway 296 in a flow path through the valve opening 280 in the contact surface 282. It should be noted that the height H4 and the width W5 of the narrow section 276 are such that contact of the vertical wall 278 by the flow path is minimized. Therefore, the potential for accumulation of the mineral deposits, of the type shown in Figure 3, on the vertical wall 278 from the metallic compounds in the condensate 60 passing through the narrow section 276 is minimized. In a preferred embodiment, contact of the vertical wall 278 by the flow path is eliminated, thereby eliminating the mineral deposits. The condensate 60 from the narrow section 276 of the valve seat 274 continues in the flow path downstream into a wide section 290 of the valve seat 274. The wide section 290 has a width greater than the width W5 of the narrow section 276. The passageway 296 allows for fluid communication between the chamber 30 and the outlet fitting 234. More specifically, the passageway 296 preferably includes the flow path from the opening 280 through the narrow section 276, the downstream wide section 290, and the outlet fitting 234. Referring now to Figure 5, an alternate embodiment of a valve seat 374 is shown. The valve seat 374 includes a narrow section 376 having a vertical wall 378. The narrow section 376 has a height H5 and a width W6. The ratio of the width W6 of the narrow section 376 to the height H5 of the narrow section 376 is greater than about 2: 1. The valve seat 374 includes a passageway 396. The passageway 396 allows for fluid communication between the chamber 30 and the outlet fitting 334.

The condensate 60 in the chamber 30 enters the narrow section 376 in a flow path through an opening 380 in a contact surface 382. It should be noted that the height H5 and the width W6 of the narrow section 376 are such that contact of the vertical wall 378 by the flow path is minimized. Therefore, the potential for accumulation of the mineral deposits, of the type shown in Figure 3, on the vertical wall 378 from the metallic compounds in the condensate 60 passing through the narrow section 376 is minimized. In a preferred embodiment, contact of the vertical wall 378 by the flow path is eliminated, thereby eliminating the mineral deposits. The condensate 60 from the narrow section 376 of the valve seat 374 continues in the flow path downstream into a wide section 390 of the valve seat 374. The wide section 390 has a width greater than the width W6 of the narrow section 376. The wide section 390 preferably diverges from the narrow section 376 at an inclusive angle Al. In a preferred embodiment, the wide section 390 diverges from the narrow section 376 at the inclusive angle Al of at least about 60 degrees. The angle A 1 may be any suitable angle.

Referring now to Figure 8, the vertical wall 378 shown in Figure 5 is shown in greater detail. It should be noted that at least a portion of the vertical wall 378 is preferably angled at the angle Al . Thus, at least a portion of the narrow section 376 is angled at the angle Al . It should be understood that the vertical wall 378 having an angled portion may also be used with the valve seat shown in Figures 2 and 4 and any other suitable valve seat. Referring now to Figure 9, an alternate embodiment of a vertical wall 478 of a narrow section 476 is shown. It should be noted that at least a portion of the vertical wall 478 is preferably angled at the angle B l. Thus, at least a portion of the narrow section 476 is angled at the angle Al . The angle B l may be any suitable angle. In a preferred embodiment, the angle Bl is an inclusive angle of at least about 60 degrees. The vertical wall 478 and the narrow section 476 are included in a passageway 496. It should be understood that the vertical wall 478 having an angled portion may be used with the valve seat shown in Figures 2, 4 and 5 and any other suitable valve seat.

Without wishing to be bound by theory, it is believed that the mineral deposits on the narrow section of the valve seat are minimized or eliminated by reducing the exposure of the narrow section to contact by the impinging flow path of the condensate.

The principle and mode of operation of this invention have been described in its preferred embodiments. However, it should be noted that this invention may be practiced otherwise than as specifically illustrated and described without departing from its scope.

Claims

What is claimed is:

1. An inverted bucket steam trap, comprising: a casing forming a chamber; inlet and outlet fittings, mounted on the casing, and adapted for fluid inflow into and outflow from the chamber, respectively; a valve seat, wherein the valve seat includes a contact surface defining a valve opening and wherein the valve seat further includes a passageway that provides fluid communication from the valve opening to the outlet fitting, wherein the passageway includes a wide section and a narrow section, the narrow section being positioned between the valve opening and the wide section, and wherein the ratio of the width of the naιτow section to the height of the narrow section is greater than about 2:1; a valve member movably disposed in the chamber and adapted to be moved into and out of sealing engagement with the contact surface of the valve seat to open and close the valve opening; an operating lever disposed in the chamber and operatively connected to the valve member to vertically apply force to effect movement of the valve member toward and away from the contact surface of the valve seat, thereby closing and opening the valve opening; and a vertically movable inverted bucket provided in the chamber and operatively connected to the operating lever whereby vertical movement of the inverted bucket in the chamber will effect movement of the operating lever thereby to move the valve member into and out of sealing engagement with the valve seat.

2. The steam trap of claim 1 wherein the narrow section of the passageway is cylindrical and the ratio of the diameter of Hie valve opening to the height of -he narrow section of Hie passageway is greater than about 2: 1.

3. The steam trap of claim 1 wherein the narrow section of the passageway is cylindrical and the ratio of the diameter of the valve opening to the height of the narrow section of the passageway is greater than about 3:1.

4. The steam trap of claim 1 wherein at least a portion of the narrow section is angled.

5. The steam trap of claim 1 wherein at least a portion of the narrow section is angled at least about 60 degrees.

6. An inverted bucket steam trap, comprising: a casing forming a chamber; inlet and outlet fittings, mounted on the casing, and adapted for fluid inflow into and outflow from the chamber, respectively; a valve seat, wherein the valve seat includes a contact surface defining a valve opening and wherein the valve seat further includes a passageway that provides fluid communication from the valve opening to the outlet fitting, wherein the passageway includes a wide section and a narrow section, the narrow section being positioned between the valve opening and the wide section, wherein the narrow section of the passageway is cylindrical, and wherein the ratio of the width of the narrow section to the height of the narrow section is greater than about 3:1; a valve member movably disposed in the chamber and adapted to be moved into and out of sealing engagement with the contact surface of the valve seat to open and close the valve opening; an operating lever disposed in the chamber and operatively connected to the valve member to vertically apply force to effect movement of the valve member toward and away from the contact surface of the valve seat, thereby closing and opening the valve opening; a vertically movable inverted bucket provided in the chamber and operatively connected to the operating lever whereby vertical movement of the inverted bucket in the chamber will effect movement of the operating lever thereby to move the valve member into and out of sealing engagement with the valve seat.