CA1332035C - Pump with heat exchanger - Google Patents
Pump with heat exchangerInfo
- Publication number
- CA1332035C CA1332035C CA000616519A CA616519A CA1332035C CA 1332035 C CA1332035 C CA 1332035C CA 000616519 A CA000616519 A CA 000616519A CA 616519 A CA616519 A CA 616519A CA 1332035 C CA1332035 C CA 1332035C
- Authority
- CA
- Canada
- Prior art keywords
- seal
- pump
- injection water
- recess
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The present invention is directed to improvements in a pump of the type having a shaft seal in a seal chamber supplied with seal injection water. The invention involves a support member having an annular recess therein, a single inlet through the support member at one location for the passage of seal injection water into the recess, and an annular injection water distributor ring in the recess. The ring has a plurality of outlets therethrough for the passage of and distribution of water flowing through the inlet into the recess and thereafter into the seal chamber.
The present invention is directed to improvements in a pump of the type having a shaft seal in a seal chamber supplied with seal injection water. The invention involves a support member having an annular recess therein, a single inlet through the support member at one location for the passage of seal injection water into the recess, and an annular injection water distributor ring in the recess. The ring has a plurality of outlets therethrough for the passage of and distribution of water flowing through the inlet into the recess and thereafter into the seal chamber.
Description
133203~
B~CKGROUND OF THE INVENTION
The field of the present invention is pumps wîth heat exchangers.
In pumps used in connection with hot liquids, such as reactor cooling water, it is often advantageous or necessary to cool the pump, or pump components such as mechanical seals. To this end, heat exchangers may be provided with the pump to provide a cooling function.
For example, U.S. Patent 3,478,689 discloses a high-pressure, high temperature reactor circulating pump~having a : .
thermal plate and a heat exchanger shield for cooling a shaft seal. In addition, U.S. Patent No. 3,459,430 discloses a mechanical seal assembly having cooling coils within a cooling jacket A recirculation impeller driven by the pump shaft causes liquid to flow over the heat dissipating surfaces of a mechanical seal cartridge and a radial bearing, to cool these components. ;-~
The heat absorbed in the liquid is dissipated from the cooling coil into a liquid that flows over and around the coil. -,: .
An improved heat exchanger is described in U.S. Patent No.
4,005,747 for use with a pump assembly incorporating mechanical ;
sealls, such that the seals are cooled not only during pump operation, but also in the hot-stand-by condition. This heat exchanger is constructed with a rotating baffle which defines the '~
: ~ 1 ''~ ,'"
~.~ ,',,;.''"'~
path of hot fluid flow and which when rotating, causes rotational motion in the hot fluid. The heat exchanger is designed so that the coolant flows in a defined path along the pump shaft to the mechanical seals.
Although these known cooling techniques have performed well in the past, a further improvement in the cooling of the mechanical seals would prolong their useful life and improve reliability.
This application is a division of commonly owned Canadian Patent Application No. 560,898 filed March 9, 198~.
~UMMARY OF THE INVENTION
The present invention is directed to improvements in a pump of the type having a shaft seal in a seal chamber supplied with seal injection water. The invention involves a support member having an annular recess therein, a single inlet through the support member at one location for the passage of seal injection water into the recess, and an annular injection water distributor ring in the recess. The ring has a plurality of outlets therethrough for the passage of and distribution of water flowing through the inlet into the recess and thereafter into the seal chamber.
Other and further objects and advantages will appear hereinafter.
LCD: j j 2 1332~35 ~
In the drawings, wherein similar reference characters denote similar elements throughout the several : :
views;
5FIG. 1 is a perspective view of a pump and motor -assembly;
FIG. 2 is a fragmentarily illustrated section view taken along line 2-2 of FIG. l;
FIG. 3 is an enlarged fragmentarily illustrated 10section view of the heat exchanger and pump elements illustrated in FIG. 2;
FIG. 4 is a section view taken along line 4-4 of FIG. 3;
FIG. 5 is a section view taken along line 5-5 of ;~
FIG. 3;
,;~''`"',', ,..~.:.. :, LCD:jj 3 ;
133203~
: ~IG. 6 is a section view taken along line 6~6 of FIG. 3;
FIG. 7 is a section view taken along line 7~7 of FIG. 3;
FIG. 8 is a front elevational view of a seal injection distribution ring;
FIG. 9 is a side elevational view in part section thereof;
FIG._ 10 is a front elevational view of the slotted keyway spacer ring illustrated in FIG. 3;
FIG. 11 is a section view taken along line 11-11 of FIG. 10;
and FIG. 12 is a section view taken along line 12-12 of FIG. 3 illustrating the engagement of the hydrostatic bearing, the slot keyway spacer, and the pump cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now in particular to the appended drawings, as shown in FIG. 1, a pump assembly 20 includes a pump housing 22 having a port 24, and a driver mount 26 attached to the pump housing 22.
With reference to FIGS. 2 and 3, a pump cover 34 is secured to the pUlTlp houslng 22 with cover clamp ring 32. The motor 26 which is generally disposed at one end of the pump assembly 20 is attached to a shaft 42 extending substantially through the pump assembly 20 and joined to an impeller 36 which is rotatable within an impeller chamber 72 in the pump housing 22.
With particular reference to FIG. 3, the impeller 36 includes a cylindrical journal 40 extending from the back surface '. '' ~`.
': ' ' ;' ' ' ~
~ ~33203~
o~ the impeller into a recess 73 in the impeller chamber 72. A
cylindrical hydrostatic bearing 38 is joined to the cover 34 by a ring of fasteners 46, such that the hydrostatic bearing 38 surrounds the journal 40, thereby maintaining the journal and impeller in position and provlding a bearing function. To simplif~ alignment of the hydrostatic bearing 38 during its installation into the pump assembly 20, a slotted keyway spacer ring 120 may be installed in between the pump cover 34 and the hydrostatic bearing 38, as shown in FIG. 3.
In order to primarily contain the pumped or product fluid or water within the impeller chamber 72, and to prevent the product water from passing out of the pump housing 22 into the motor 26 along the shaft 42, a mechanical seal or seal cartridge assembly 50 is installed over the shaft 42 in between the motor 26 and the impeller 36. In certain applications, the product water pressure may reach 2500 psi so that the use of a multistage seal cartridge assembly, such as the assembly disclosed in U.S. Patent 3,459,430, is appropriate. This type of seal relies on elastic materials and the very precise near engagement of solid sealing rings with the shaft. As the product water being driven by the impeller can reach 575 F, the seal 50 should be cooled in order to maintain its sealing effectiveness.
~ccording to the present invention, a heat exchanger (collectively designated by 51) is provided within the pump assembly 20 to cool the seal 50. Referring again to FIG. 3, the heat exchanger 51 includes a rotating baffle sleeve 52 which is ~32035 leleasa~ly but securely and intimately mounted onto the shaft 42.
The rotating ba~fle sleeve 52 includes a base 53 configured to accurately match and mate with the profile of the shaft 42.
At the lower or impeller end of the base 53 is a lower bri~ge 54 integral wit~ and extending radially outwardly from the base 53.. The lower bridge 54 is ~oined to a perpendicular lower facing section 55 which extends towards a central position of the heat exchanger and away from the impeller 36 in a direction generally parallel to the base 53. The lower facing section 55 includes a tapered segment 56 at its end. Similarly, at the upper or seal end of the base 53 is an upper bridge 57 integrally joined with the base 53 and extending radially outwardly to join an upper facing section 58 mounted perpendicularly thereto.
While the upper facing section 58 extends towards the lower facing section 55 in a dlrection parallel to the base 53, a seal baffle 59 extends in the opposite direction and substantially surrounds the entire seal 50.
To facilitate manufacture and assembly of the rotating baffle sleeve 52, the sleeve may be formed by an upper baffle 61 and a lower baffle 63 releasably joined together at a joint 64.
A cooling cylinder 66 is generally suspended and fixed in position within t~le space in the rotating baffle sleeve 52 formed by the upper facing section 58, the lower facing section 55, and the base 53. The cooling cylinder 66 is formed by an inner enclosing cylinder 68 having a grooved outer surface, which is spaced apart from an outer enclosing cylinder 67 which has a 133203~
~rooved inner surface. The inner and outer enclosing cylinders are joined together at their ends. ~he outer enclosing cylinder 67 extends beyond the rotating baffle sleeve and is attached to and supported by a barrel support 69. As the cooling cylinder 66 is suspended within the rotating baffle sleeve 52, a flow passageway 74 is formed by the outside surfaces of the cooling cylinder 66 and the inside surfaces of the rotating baffle sleeve 52. The flow passageway 74 opens at one end into the impeller chamber 72, extends through the heat exchanger 51, over the seal baffle 59 to a juncture 84 and then into a seal chamber 70.
As shown in FIGS. 4, 5, and 6, contained within the cooling cylinder 66 is a spacer cylinder 65 having a pluxality of radially spaced apart grooves 60 on its outside surface. Similar to the flow passageway 74, the grooves 60 on the spacer cylinder 65 form a component cooling water passageway 71 in between the spacer cylinder 65 and the cooling cylinder 66. Passageway 71 is linked to an inlet 78 and an outlet 79 formed within the barrel support 69. A pair of ducts 75 in the barrel support 69 link the inlet 78 and the outlet 79 to a component cooling water source through a port 76 in the pump cover 34.
~ d~acent to the component water passageway 76 is a seal injection water supply duct 80 which supplies seal injection water to an injection water distributor ring 90 positioned in between the injection supply duct ~0 and the duct junction 84 adjacent to the seal 50.
The seal injection distributor ring 90, as shown in FIGS. 8 :
13~203~
~~ alld 9, comprises an annular ring having a plurality of spaced apart distribution openings 92. The injection water supply duct 80 connects to the distributor ring 90 at a single location. As show in FIG. 3, the distributor ring 90 is disposed w.ithin a recess in an upper flange 88 of the barrel support 69. As the injection water enters the distributor ring 90 it is uniformly distributed circumferentially around the ring via the ring opening 92.
The openings 92 may vary in size, if so desired.
At the end of the barrel support 69 adjacent to the impeller chamber recess 73 is a thermal shield 48 set ~;
into an annular groove 45 in the barrel support 69. The thermal shield 48 includes plural spaced apart rings 47 and 49 forming a stagnant water cavity 43 therebetween, as best shown in FIG. 3. The insulation provided by the thermal shield 48 acts to prevent sudden and extreme ~
temperature variations in the portion of the barrel ;:
sul~port facing the recess 73, thereby reducing temperature related stresses in the barrel support 69. ~lternatively, ~
the heat shield may comprise a thickened material section ~:
at the end of the barrel support 69. --FIGS. 10, 11 and 12 illustrate a slotted keyway spacer ~: ring 120 which is disposed in between the pump cover 34 and the hydrostatic bearing 38. The slotted keyway ::~
spacer ring 120 has radially spaced apart holes 122 in alignment with the fasteners 46 engagnlng the cover 34. In addition, the spacer ring 120 includes four or more equally spaced apart radial keyway slots 124 which engage keys 126 on the pump cover 34.
8 ~:~
~'';'.
,,,( , .: :
- . 133203~
The p~mp has two modes o~ operation, depending upon whether seal injection water is available. During normal operation, seal injection water is available and flows through the duct 80, is distributed by injection distributor ring 90 and runs into the seal chamber 70. The seal injection water is preferably supplied at appro~. 105 F, so that the seal 50 and seal cartridge is maintained at a relatively cool operating temperature. In -addition, the seal injection water is clean water so that dirt and impurities are prevented from reaching the seal 50 and the cartridge. The solid arrows in FIG. 3 represent the flow pattern in the pump during normal operation with seal injection water, and the phantom arrows represent the flow pattern when no seal injection water is available.
Once the seal chamber 70 is filled with seal injection water, a small portion of the water in the seal chamber 70 flows through the seal 50 and the seal cartridge, and the remaining seal injection water supply flows outwardly through the junction 84 through the heat exchange flow passageway 74 in the heat exchanger 51, and then into the impeller chamber 72 where it becomes part of the product water. Simultaneously, component ;
cooling water is provided through the ducts 76 and 75 and through the inle~ 78 into the cooling cylinder 66. The component cooling water then circulates through the cooling cylinder 66, guided by the openings and grooves in the spacer cylinder 65 and the inner and outer enclosing cylinders 67 and 68, and then passes through the outlet 79 and is returned to the component cooling water ~ `:
9 ,, 133203~
source. As the seal injection water flowing through the heat exchange flow passageway 74 is at a relatively low temperature, and at approximately the same temperature as the product cooling water flowing within the product cooling water passageway 71, there is little or no heat exchange occurring when seal injection water is ~vailable.
However, in the second mode of operation of the pump, i.e., when there is no seal injection water available (or in pumps which are not adapted to accept seal injection water) the operation of the heat exchanger 51 becomes critical. When no seal injection water is provided, the high temperature (e.g. 575 F) product water enters the flow passageway 74 from the impeller chamber 72, flows through the heat exchanger 51 and the junction 84 and into the seal chamber 70. As the cooling cylinder 66 is continuously provided with a flow of component cooling water at e.g. 90 F, there is a very large temperature difference between the product water flowing through passageway 74 and the component cooling water flowing through passageway 71. Therefore, a high rate of heat transfer occurs through the walls of the cooling cylinder (i.e., through the outer enclosing cylinder 67 and the inner enclosing cylinder 68). Thus the product water is substantially cooled as it flows through the heat exchanger 51 before it comes into contact with the seal 50 and seal cartridge.
As a result, even in the absence of seal injection water, the seal is maintained at an operational acceptable temperature.
Moreover, the rotating baffle sleeve helps in buffering ~`
; 133203~
temperature changes induced in the seal 50 and seal cartridge and mitigates temperature related stresses in the shaft.
The heat exchanger 51 achieves a high level of cooling efficiency by virtue of the large amount of surface area provided, the dual directional flow of the product cooling water therein, as well as the counterflow cooling design.
While the seal baffle 59 provides an extended heat exchange surface, it also insures that the seal chamber 70 is filled with injection water, before any injection water flows into the heat exchanger 51 at startup. In addition, the centrifugal effect imparted to the water by the seal baffle tends to drive suspended particles outwardly and away from the seal 50.
Furthermore with the present construction a major heat transfer -area is located in a relatively cold region of the heat exchanger, i.e., the last pass of the product water through the heat exchanger occurs adjacent to the relatively cool upper baffle 61. This configuration helps to prevent a reduction in cooling effectiveness caused by conductive heat transfer from impeller chamber surfaces into the already cooled product water from toward the seal cartridge.
As the component cooling water flows continuously regardless of the presence or absence of the seal injection water, a very high temperature gradient is estab:Lished across the end of the barrel support 69, because component cooling water at e.g. 90 F is separated from product water at e.g. 575 F by a relatively thin wall. In order to reduce thermal stresses in this region, the thermal shield 48 is provided at the end of the barrel t3~2035 support 69, and acts as an insulator therein.
The heat exchanger 51 is designed so that it may be readily retrofitted onto existing pumps with replacement of the existing pump cover. In addition, the heat exchanger 51 is easily removable from the pump assembly 20 for inspection or service. Initially, the seal 50 is slidably removed from the shaft 42. The upper baffle 61, which may be held in position on the shaft with a lock ring, is then similarly slidably removed from the shaft 42. With the upper baffle 61 now out of the way, the entire heat exchanger assembly 51 including the cooling cylinder 66 and its components 67, 68, and 65, as well as the barrel support 69 carrying the ducts 75 and 76, the inlet 78 and outlet 79, and the thermal shield 49, can all then be removed as a single unit. Thereafter, the lower baffle 63 may also be slidably removed from the shaft 42. During reassembly, the above-described steps are reversed.
:.: ., ,;;
During installation or replacement of the hydrostatic bearing 38, the bearing is secured to the radially slotted keyway spacer ring 120 via retainer bolts ;~
128, as shown on FIG. 12. The keyway slots or grooves 124 `
in the spacer ring 120 are then engaged over the keys 126 , -protruding from the pump cover 34, in order to accurately position the bearing 38 over the journal 40 without the need for repeated time consuming indicating measurements after the initial installation of the hydrostatic bearing. The `
radially slotted keyway spacer ring feature is a significant ! '-advantage during bearing replacement because the pump may be used LCD:jj 12 :
133203~
n nuclear power generation installations and become radioactive, thereby severely limiting the amount of time any single operator has available for servicing the pump.
Thus, a pump having an improved heat exchanger for cooling a seal, as well as a novel seal injection water distributor ring, a thermal ~hield, and a radially slotted keyway spacer ring for a hydrostatic bearing are disclosed. While embodiments and applications of this invention have been shown and described it would be apparent to those skilled in he art that many more modifications are possible without departing from the inventive conceptS herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
~ ~... . . .
B~CKGROUND OF THE INVENTION
The field of the present invention is pumps wîth heat exchangers.
In pumps used in connection with hot liquids, such as reactor cooling water, it is often advantageous or necessary to cool the pump, or pump components such as mechanical seals. To this end, heat exchangers may be provided with the pump to provide a cooling function.
For example, U.S. Patent 3,478,689 discloses a high-pressure, high temperature reactor circulating pump~having a : .
thermal plate and a heat exchanger shield for cooling a shaft seal. In addition, U.S. Patent No. 3,459,430 discloses a mechanical seal assembly having cooling coils within a cooling jacket A recirculation impeller driven by the pump shaft causes liquid to flow over the heat dissipating surfaces of a mechanical seal cartridge and a radial bearing, to cool these components. ;-~
The heat absorbed in the liquid is dissipated from the cooling coil into a liquid that flows over and around the coil. -,: .
An improved heat exchanger is described in U.S. Patent No.
4,005,747 for use with a pump assembly incorporating mechanical ;
sealls, such that the seals are cooled not only during pump operation, but also in the hot-stand-by condition. This heat exchanger is constructed with a rotating baffle which defines the '~
: ~ 1 ''~ ,'"
~.~ ,',,;.''"'~
path of hot fluid flow and which when rotating, causes rotational motion in the hot fluid. The heat exchanger is designed so that the coolant flows in a defined path along the pump shaft to the mechanical seals.
Although these known cooling techniques have performed well in the past, a further improvement in the cooling of the mechanical seals would prolong their useful life and improve reliability.
This application is a division of commonly owned Canadian Patent Application No. 560,898 filed March 9, 198~.
~UMMARY OF THE INVENTION
The present invention is directed to improvements in a pump of the type having a shaft seal in a seal chamber supplied with seal injection water. The invention involves a support member having an annular recess therein, a single inlet through the support member at one location for the passage of seal injection water into the recess, and an annular injection water distributor ring in the recess. The ring has a plurality of outlets therethrough for the passage of and distribution of water flowing through the inlet into the recess and thereafter into the seal chamber.
Other and further objects and advantages will appear hereinafter.
LCD: j j 2 1332~35 ~
In the drawings, wherein similar reference characters denote similar elements throughout the several : :
views;
5FIG. 1 is a perspective view of a pump and motor -assembly;
FIG. 2 is a fragmentarily illustrated section view taken along line 2-2 of FIG. l;
FIG. 3 is an enlarged fragmentarily illustrated 10section view of the heat exchanger and pump elements illustrated in FIG. 2;
FIG. 4 is a section view taken along line 4-4 of FIG. 3;
FIG. 5 is a section view taken along line 5-5 of ;~
FIG. 3;
,;~''`"',', ,..~.:.. :, LCD:jj 3 ;
133203~
: ~IG. 6 is a section view taken along line 6~6 of FIG. 3;
FIG. 7 is a section view taken along line 7~7 of FIG. 3;
FIG. 8 is a front elevational view of a seal injection distribution ring;
FIG. 9 is a side elevational view in part section thereof;
FIG._ 10 is a front elevational view of the slotted keyway spacer ring illustrated in FIG. 3;
FIG. 11 is a section view taken along line 11-11 of FIG. 10;
and FIG. 12 is a section view taken along line 12-12 of FIG. 3 illustrating the engagement of the hydrostatic bearing, the slot keyway spacer, and the pump cover.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now in particular to the appended drawings, as shown in FIG. 1, a pump assembly 20 includes a pump housing 22 having a port 24, and a driver mount 26 attached to the pump housing 22.
With reference to FIGS. 2 and 3, a pump cover 34 is secured to the pUlTlp houslng 22 with cover clamp ring 32. The motor 26 which is generally disposed at one end of the pump assembly 20 is attached to a shaft 42 extending substantially through the pump assembly 20 and joined to an impeller 36 which is rotatable within an impeller chamber 72 in the pump housing 22.
With particular reference to FIG. 3, the impeller 36 includes a cylindrical journal 40 extending from the back surface '. '' ~`.
': ' ' ;' ' ' ~
~ ~33203~
o~ the impeller into a recess 73 in the impeller chamber 72. A
cylindrical hydrostatic bearing 38 is joined to the cover 34 by a ring of fasteners 46, such that the hydrostatic bearing 38 surrounds the journal 40, thereby maintaining the journal and impeller in position and provlding a bearing function. To simplif~ alignment of the hydrostatic bearing 38 during its installation into the pump assembly 20, a slotted keyway spacer ring 120 may be installed in between the pump cover 34 and the hydrostatic bearing 38, as shown in FIG. 3.
In order to primarily contain the pumped or product fluid or water within the impeller chamber 72, and to prevent the product water from passing out of the pump housing 22 into the motor 26 along the shaft 42, a mechanical seal or seal cartridge assembly 50 is installed over the shaft 42 in between the motor 26 and the impeller 36. In certain applications, the product water pressure may reach 2500 psi so that the use of a multistage seal cartridge assembly, such as the assembly disclosed in U.S. Patent 3,459,430, is appropriate. This type of seal relies on elastic materials and the very precise near engagement of solid sealing rings with the shaft. As the product water being driven by the impeller can reach 575 F, the seal 50 should be cooled in order to maintain its sealing effectiveness.
~ccording to the present invention, a heat exchanger (collectively designated by 51) is provided within the pump assembly 20 to cool the seal 50. Referring again to FIG. 3, the heat exchanger 51 includes a rotating baffle sleeve 52 which is ~32035 leleasa~ly but securely and intimately mounted onto the shaft 42.
The rotating ba~fle sleeve 52 includes a base 53 configured to accurately match and mate with the profile of the shaft 42.
At the lower or impeller end of the base 53 is a lower bri~ge 54 integral wit~ and extending radially outwardly from the base 53.. The lower bridge 54 is ~oined to a perpendicular lower facing section 55 which extends towards a central position of the heat exchanger and away from the impeller 36 in a direction generally parallel to the base 53. The lower facing section 55 includes a tapered segment 56 at its end. Similarly, at the upper or seal end of the base 53 is an upper bridge 57 integrally joined with the base 53 and extending radially outwardly to join an upper facing section 58 mounted perpendicularly thereto.
While the upper facing section 58 extends towards the lower facing section 55 in a dlrection parallel to the base 53, a seal baffle 59 extends in the opposite direction and substantially surrounds the entire seal 50.
To facilitate manufacture and assembly of the rotating baffle sleeve 52, the sleeve may be formed by an upper baffle 61 and a lower baffle 63 releasably joined together at a joint 64.
A cooling cylinder 66 is generally suspended and fixed in position within t~le space in the rotating baffle sleeve 52 formed by the upper facing section 58, the lower facing section 55, and the base 53. The cooling cylinder 66 is formed by an inner enclosing cylinder 68 having a grooved outer surface, which is spaced apart from an outer enclosing cylinder 67 which has a 133203~
~rooved inner surface. The inner and outer enclosing cylinders are joined together at their ends. ~he outer enclosing cylinder 67 extends beyond the rotating baffle sleeve and is attached to and supported by a barrel support 69. As the cooling cylinder 66 is suspended within the rotating baffle sleeve 52, a flow passageway 74 is formed by the outside surfaces of the cooling cylinder 66 and the inside surfaces of the rotating baffle sleeve 52. The flow passageway 74 opens at one end into the impeller chamber 72, extends through the heat exchanger 51, over the seal baffle 59 to a juncture 84 and then into a seal chamber 70.
As shown in FIGS. 4, 5, and 6, contained within the cooling cylinder 66 is a spacer cylinder 65 having a pluxality of radially spaced apart grooves 60 on its outside surface. Similar to the flow passageway 74, the grooves 60 on the spacer cylinder 65 form a component cooling water passageway 71 in between the spacer cylinder 65 and the cooling cylinder 66. Passageway 71 is linked to an inlet 78 and an outlet 79 formed within the barrel support 69. A pair of ducts 75 in the barrel support 69 link the inlet 78 and the outlet 79 to a component cooling water source through a port 76 in the pump cover 34.
~ d~acent to the component water passageway 76 is a seal injection water supply duct 80 which supplies seal injection water to an injection water distributor ring 90 positioned in between the injection supply duct ~0 and the duct junction 84 adjacent to the seal 50.
The seal injection distributor ring 90, as shown in FIGS. 8 :
13~203~
~~ alld 9, comprises an annular ring having a plurality of spaced apart distribution openings 92. The injection water supply duct 80 connects to the distributor ring 90 at a single location. As show in FIG. 3, the distributor ring 90 is disposed w.ithin a recess in an upper flange 88 of the barrel support 69. As the injection water enters the distributor ring 90 it is uniformly distributed circumferentially around the ring via the ring opening 92.
The openings 92 may vary in size, if so desired.
At the end of the barrel support 69 adjacent to the impeller chamber recess 73 is a thermal shield 48 set ~;
into an annular groove 45 in the barrel support 69. The thermal shield 48 includes plural spaced apart rings 47 and 49 forming a stagnant water cavity 43 therebetween, as best shown in FIG. 3. The insulation provided by the thermal shield 48 acts to prevent sudden and extreme ~
temperature variations in the portion of the barrel ;:
sul~port facing the recess 73, thereby reducing temperature related stresses in the barrel support 69. ~lternatively, ~
the heat shield may comprise a thickened material section ~:
at the end of the barrel support 69. --FIGS. 10, 11 and 12 illustrate a slotted keyway spacer ~: ring 120 which is disposed in between the pump cover 34 and the hydrostatic bearing 38. The slotted keyway ::~
spacer ring 120 has radially spaced apart holes 122 in alignment with the fasteners 46 engagnlng the cover 34. In addition, the spacer ring 120 includes four or more equally spaced apart radial keyway slots 124 which engage keys 126 on the pump cover 34.
8 ~:~
~'';'.
,,,( , .: :
- . 133203~
The p~mp has two modes o~ operation, depending upon whether seal injection water is available. During normal operation, seal injection water is available and flows through the duct 80, is distributed by injection distributor ring 90 and runs into the seal chamber 70. The seal injection water is preferably supplied at appro~. 105 F, so that the seal 50 and seal cartridge is maintained at a relatively cool operating temperature. In -addition, the seal injection water is clean water so that dirt and impurities are prevented from reaching the seal 50 and the cartridge. The solid arrows in FIG. 3 represent the flow pattern in the pump during normal operation with seal injection water, and the phantom arrows represent the flow pattern when no seal injection water is available.
Once the seal chamber 70 is filled with seal injection water, a small portion of the water in the seal chamber 70 flows through the seal 50 and the seal cartridge, and the remaining seal injection water supply flows outwardly through the junction 84 through the heat exchange flow passageway 74 in the heat exchanger 51, and then into the impeller chamber 72 where it becomes part of the product water. Simultaneously, component ;
cooling water is provided through the ducts 76 and 75 and through the inle~ 78 into the cooling cylinder 66. The component cooling water then circulates through the cooling cylinder 66, guided by the openings and grooves in the spacer cylinder 65 and the inner and outer enclosing cylinders 67 and 68, and then passes through the outlet 79 and is returned to the component cooling water ~ `:
9 ,, 133203~
source. As the seal injection water flowing through the heat exchange flow passageway 74 is at a relatively low temperature, and at approximately the same temperature as the product cooling water flowing within the product cooling water passageway 71, there is little or no heat exchange occurring when seal injection water is ~vailable.
However, in the second mode of operation of the pump, i.e., when there is no seal injection water available (or in pumps which are not adapted to accept seal injection water) the operation of the heat exchanger 51 becomes critical. When no seal injection water is provided, the high temperature (e.g. 575 F) product water enters the flow passageway 74 from the impeller chamber 72, flows through the heat exchanger 51 and the junction 84 and into the seal chamber 70. As the cooling cylinder 66 is continuously provided with a flow of component cooling water at e.g. 90 F, there is a very large temperature difference between the product water flowing through passageway 74 and the component cooling water flowing through passageway 71. Therefore, a high rate of heat transfer occurs through the walls of the cooling cylinder (i.e., through the outer enclosing cylinder 67 and the inner enclosing cylinder 68). Thus the product water is substantially cooled as it flows through the heat exchanger 51 before it comes into contact with the seal 50 and seal cartridge.
As a result, even in the absence of seal injection water, the seal is maintained at an operational acceptable temperature.
Moreover, the rotating baffle sleeve helps in buffering ~`
; 133203~
temperature changes induced in the seal 50 and seal cartridge and mitigates temperature related stresses in the shaft.
The heat exchanger 51 achieves a high level of cooling efficiency by virtue of the large amount of surface area provided, the dual directional flow of the product cooling water therein, as well as the counterflow cooling design.
While the seal baffle 59 provides an extended heat exchange surface, it also insures that the seal chamber 70 is filled with injection water, before any injection water flows into the heat exchanger 51 at startup. In addition, the centrifugal effect imparted to the water by the seal baffle tends to drive suspended particles outwardly and away from the seal 50.
Furthermore with the present construction a major heat transfer -area is located in a relatively cold region of the heat exchanger, i.e., the last pass of the product water through the heat exchanger occurs adjacent to the relatively cool upper baffle 61. This configuration helps to prevent a reduction in cooling effectiveness caused by conductive heat transfer from impeller chamber surfaces into the already cooled product water from toward the seal cartridge.
As the component cooling water flows continuously regardless of the presence or absence of the seal injection water, a very high temperature gradient is estab:Lished across the end of the barrel support 69, because component cooling water at e.g. 90 F is separated from product water at e.g. 575 F by a relatively thin wall. In order to reduce thermal stresses in this region, the thermal shield 48 is provided at the end of the barrel t3~2035 support 69, and acts as an insulator therein.
The heat exchanger 51 is designed so that it may be readily retrofitted onto existing pumps with replacement of the existing pump cover. In addition, the heat exchanger 51 is easily removable from the pump assembly 20 for inspection or service. Initially, the seal 50 is slidably removed from the shaft 42. The upper baffle 61, which may be held in position on the shaft with a lock ring, is then similarly slidably removed from the shaft 42. With the upper baffle 61 now out of the way, the entire heat exchanger assembly 51 including the cooling cylinder 66 and its components 67, 68, and 65, as well as the barrel support 69 carrying the ducts 75 and 76, the inlet 78 and outlet 79, and the thermal shield 49, can all then be removed as a single unit. Thereafter, the lower baffle 63 may also be slidably removed from the shaft 42. During reassembly, the above-described steps are reversed.
:.: ., ,;;
During installation or replacement of the hydrostatic bearing 38, the bearing is secured to the radially slotted keyway spacer ring 120 via retainer bolts ;~
128, as shown on FIG. 12. The keyway slots or grooves 124 `
in the spacer ring 120 are then engaged over the keys 126 , -protruding from the pump cover 34, in order to accurately position the bearing 38 over the journal 40 without the need for repeated time consuming indicating measurements after the initial installation of the hydrostatic bearing. The `
radially slotted keyway spacer ring feature is a significant ! '-advantage during bearing replacement because the pump may be used LCD:jj 12 :
133203~
n nuclear power generation installations and become radioactive, thereby severely limiting the amount of time any single operator has available for servicing the pump.
Thus, a pump having an improved heat exchanger for cooling a seal, as well as a novel seal injection water distributor ring, a thermal ~hield, and a radially slotted keyway spacer ring for a hydrostatic bearing are disclosed. While embodiments and applications of this invention have been shown and described it would be apparent to those skilled in he art that many more modifications are possible without departing from the inventive conceptS herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
~ ~... . . .
Claims (2)
1. In a pump of the type having a shaft seal in a seal chamber supplied with seal injection water, the improvement comprising:
an annular support member;
an annular recess in said support member;
a single inlet through said support member at one location for the passage of seal injection water into said recess; and an annular injection water distributor ring disposed in said recess and having a plurality of outlets therethrough for the passage of and distribution of water flowing through said inlet into said recess and thereafter into said seal chamber.
an annular support member;
an annular recess in said support member;
a single inlet through said support member at one location for the passage of seal injection water into said recess; and an annular injection water distributor ring disposed in said recess and having a plurality of outlets therethrough for the passage of and distribution of water flowing through said inlet into said recess and thereafter into said seal chamber.
2. The distributor ring of claim 1 wherein said outlets are openings of varying size.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000616519A CA1332035C (en) | 1987-03-17 | 1992-11-17 | Pump with heat exchanger |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/026,767 US4775293A (en) | 1987-03-17 | 1987-03-17 | Pump with heat exchanger |
| US026,767 | 1987-03-17 | ||
| CA000568988A CA1329854C (en) | 1987-06-09 | 1988-06-08 | Biodegradable polymeric materials based on polyether glycols, processes for the preparation thereof and surgical articles made therefrom |
| CA000616519A CA1332035C (en) | 1987-03-17 | 1992-11-17 | Pump with heat exchanger |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000560898A Division CA1319564C (en) | 1987-03-17 | 1988-03-09 | Pump with heat exchanger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1332035C true CA1332035C (en) | 1994-09-20 |
Family
ID=25671924
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616520A Expired - Fee Related CA1332034C (en) | 1987-03-17 | 1992-11-17 | Pump with heat exchanger |
| CA000616519A Expired - Fee Related CA1332035C (en) | 1987-03-17 | 1992-11-17 | Pump with heat exchanger |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616520A Expired - Fee Related CA1332034C (en) | 1987-03-17 | 1992-11-17 | Pump with heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| CA (2) | CA1332034C (en) |
-
1992
- 1992-11-17 CA CA000616520A patent/CA1332034C/en not_active Expired - Fee Related
- 1992-11-17 CA CA000616519A patent/CA1332035C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA1332034C (en) | 1994-09-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0283292B1 (en) | Pump with heat exchanger | |
| US4872689A (en) | Mechanical seal with heat exchanger | |
| EP0163552B1 (en) | Mechanical seal assembly with coolant circulation structure | |
| JP3359366B2 (en) | Pump magnetic coupling cooling system | |
| US5201642A (en) | Magnetic drive pump | |
| US5378121A (en) | Pump with fluid bearing | |
| US5217234A (en) | Mechanical seal with barrier fluid circulation system | |
| JP4124525B2 (en) | Centrifugal pump with integral axial field motor | |
| US5197863A (en) | Bearing fluid distribution systems for liquid ring pumps with rotating lobe liners | |
| US5129795A (en) | Motor driven pump | |
| EP2481960B1 (en) | Mechanical seal | |
| EP1788290B1 (en) | Mechanical seal device | |
| CA1072595A (en) | Heat exchanger | |
| EP0235505A2 (en) | Bearing cooling apparatus of heating roller | |
| US4932836A (en) | Pump with heat exchanger | |
| US5624245A (en) | Centrufugal pump with thermally isolated and dynamically air cooled shaft seal assembly | |
| US5288213A (en) | Pump having an internal pump | |
| US4005747A (en) | Multi-flow, multi-path heat exchanger for pump-mechanical seal assembly | |
| CA2051330C (en) | Pump stuffing box with heat exchange device | |
| EP0470747B1 (en) | Pump with seal purge heater | |
| US3013500A (en) | Sealed dynamoelectric machine | |
| CA1332035C (en) | Pump with heat exchanger | |
| KR970001416B1 (en) | Nuclear reactor coolant pump impeller/shaft assembly | |
| KR19990062576A (en) | Improved liquid-cooled internal combustion engine | |
| US3960467A (en) | Cooling device for a pump motor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |