US3809496A

US3809496A - Condensation apparatus

Info

Publication number: US3809496A
Application number: US00279152A
Authority: US
Inventors: D Hansen
Original assignee: General Signal Corp
Current assignee: SPX Corp
Priority date: 1972-08-09
Filing date: 1972-08-09
Publication date: 1974-05-07
Anticipated expiration: 1991-05-07
Also published as: CA980642A

Abstract

A tank for receiving and storing condensation has walls constructed of a plurality of laminations of fiberglass cloth and epoxy resin. A metallic plate, preferably of an aluminum alloy is molded into one of the walls for supporting a condensate pump. A condensate return opening in the metallic plate is aligned with a supply port in the pump so that condensation may be drawn from the tank by the pump.

Description

ansen ay 7, 1974 [54] CONDENSATION APPARATUS 3,316,847 7 5/1967 Mandy 419/360 3, 74,585 1 63 2 [75] Inventor Dmald Hansen North Aurora 3,269,398 7/366 253/3;

[73] Assignee: General Signal Corporation,

Rochester, NY. Primary ExaminerWilliam L. Freeh [22] Filed Aug 9 1972 Attorney, Agent, or Firm-Jeffrey S. Mednick 21 A l. N 279,152 1 pp 7 57 ABSTRACT [52 us. Cl 417/40 237/63 417/360 A tank receiving and Swing cmdensation has [51] Int. Cl. Ftl lb 49/00 walls constructed of a plurality of laminations of fiber [58] Field of Search 237/63. 220/83. 417/40 glass cloth and epoxy resin. A metallic plate, prefera- 417/424 6 bly of an aluminum alloy is molded into one of the wallsfor supporting a condensate pump. A condensate [56] References Cited I return opening in the metallic plate is aligned with a supply port in the pump so that condensation may be UNITED STATES PATENTS drawn from the tank by the pump. 3,282,468 ll/l966 Karlen 417/40 3,298,560 l/l967 Anderson 220/83 8 Claims, 5 Drawing Figures Q I u 32 60 t s L ;3 E2 s PM 7 I914 T 3.809.496

SHEET 1 0F 2 RADIAToR RADIATOR RADIATOR 9.9 LQQ 20 b "T g E 68 BOILER PATENTEDNAY H914 3,809,496

SHEU 2 BF 2 Illl IHH 1 CONDENSATI'ON APPARATUS BACKGROUND OF THE INVENTION 1. Field of Use While the invention is subject to a wide rang'eof applications, it is especially suited for use in a system for returning hot water condensation to a boiler'or boiler feed set and will be particularly described in that connection.

2. Description of the Prior Art Condensation apparatuses provide for the return of hot water condensation from radiators, coils, pipes, etc., to high or low pressure boilers. Similar apparatuses are also utilized in industrial complexes for returning liquid to overhead'storagetanks or gravitational circulating systems. In addition, they have many other unique uses.

For many years, most condensate apparatuses have utilized cast iron or fabricated steel tanks for liquid storage. Both cast iron and steel are costly to manufacture and are susceptible to corrosion and leaking. They require corrosion resistant coatings and painting for effective elimination of rust. Cast iron tanks are difficult to cast and are very heavy. Steel tanks are lighter than cast iron but require complicated forming techniques. Steel also requires very accurate welding and this is subject to rusting a'nd leaking. Both cast iron and steel are good conductors of heat and electricity and require special precautions against burns.

It is an object of the present invention to provide an apparatus for receiving and storing condensation that is relatively inexpensive to manufacture.

It is a further object of the present invention to provide an apparatus for receiving and storing condensation that is inert to an extremely wide rangeof corrosives, especially at elevated'tempera'tures. The scalding action and ultimate corrosion frequently associated with welds or coatings does not exist in the apparatus of the present invention. There are no metal chips to dislodge that will cause damage to the system.

It is a further object of the present invention to provide an apparatus for receiving and storing condensation that is relatively simple to manufacture.

It is a further object of the present invention to provide an apparatus for receiving and storing condensation that is relatively light in weight. For example, a condensation tank made in accordance with the present invention weighs approximately one-sixth the weight of a cast iron tank of similar size and approximately one-quarter the weight ofa steel tank ofa similar size. This reduced weight results in cost savings in shipping costs, freight handling costs and installation costs.

It is a further object of the present invention to provide an apparatus for receiving and storing condensation having a relatively low heat loss due to poor conduction characteristics. This is an important safety feature, since it reduces the possibility ofa person burning himself.

It is a further object of the present invention to pro vide an apparatus for receiving and storing condensation that will be attractive andyield many years of carefree service.

It is a further object of the present invention to provide an apparatus containing all of the features stated hereinabove and still capable of supporting a condensate pump.

SUMMARY OF INVENTION In accordance with the present invention, an apparatus receives and stores condensation. The apparatus includes a tank having walls constructed of a plurality of laminations of fiberglass cloth and epoxy resin. A metallic plate is molded into one of the walls of the tank to support a condensate pump. A condensate return opening in the metallic plate is positioned for alignment 'with a supply port in the condensate pump so that con densation may be drawn from the tank by the pump.

Further, in accordance with the present invention an apparatus receives and stores condensation and then returns it to a given location. The apparatus comprises a tank means for receiving and storing the condensation, and a pump means for returning the condensation from the tank means to the location. The tank means has walls that are constructed of a plurality of laminations of fiberglass cloth and epoxy resin. A metallic plate is molded into one of the walls of the tank means and the pump means are mounted on said plate. The plate has a condensate return opening aligned with a supply port in the pump means so that condensation may be drawn from the tank means to the location by the pump means.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description, taken in connection with the accompanying drawings, while its scope will be pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view illustrating a typical heating system in which the condensation apparatus of the present invention may be used;

FIG. 2 is an end view, partly in section, illustrating the condensate tank of the present invention supporting a condensate pump, with portions of a wall of the tank being broken away for clarity;

FIG. 3 is a perspective view of the condensate tank supporting the condensate pump;

FIG. 4 is a cross-sectional view of the condensation tank taken along lines 4-4 in FIG. 3; and

FIG. 5 is a perspective view of a metallic plate embedded in a wall of the condensate tank, a portion of the wall being broken away for clarity.

DESCRIPTION OF THE PREFERRED EMBODIMENT In accordance with the present invention, an apparatus receives and stores condensation 12. The apparatus preferably comprises a

tank having walls

22 and 25 constructed of a plurality of laminations of tiberglass cloth 24 and epoxy resin 26. A metallic plate is molded into one of the walls 22 of the tank 20 to support a condensate pump 50. A condensate return opening 32 in the metallic plate 30 is positioned for alignment with a supply port 52 in the condensate pump so that condensation 12 may be drawn from the tank 20 by the pump 50.

Referring to FIG. I, there is shown a schematic view of a typical heating system in which the condensation apparatus of the present invention may be used. FIG. 1 shows a condensation apparatus 10 comprising a tank 20 and a pump 50 connected by pipeline 68 to a boiler 1 70. Boiler 70'. is connected by pipeline 72 to heating units which may, for example, be

radiators

80, 90 and 100.

Radiators

80, 90 and 100 are'connected by pipe line 74 to condensation apparatus 10.

In operation, boiler 70 heats water to provide steam at temperatures from approximately 210 F toapproximately 275 F. The steam is circulated through line 72 to heating units. The heating units may be of any suitable well-known type, but there is shown, by way of example, three

radiators

80, 90 and 100. Steam condenses in the radiators and returns through pipeline 74 to condensate tank 20 of the condensation apparatus 10.

As can best be seen in FIG. 2 to 5, condensation apparatus includes a tank for receiving, storing and supplying the condensation, and a pump 50 for pumping the condensation from the tank to a given location (such as boiler 70). The tank 20-has

walls

22 and 25,v

preferably constructed of a plurality of laminations of woven fiberglass cloth 24 and epoxy resin 26. A metallic plate 30 is molded into one of the walls 22. The pump 50 is mounted on the plate 30 by means of bolts 34 which project through holes 36 in the pump flange 38 and taps 40 in metallic plate 30. A shim S may be placed beneath pump 50 to act as a means for assisting in the support of pump 50. Metallic plate 30 has a condensate return opening 32 aligned with a supply port 52 in the pump (see FIG. 2) so that condensation may be drawn from the tank 20 to the desired location by the pump 50. A waterlevel gauge 48 may be used to indicate the level of condensation l2 and the condition thereof. The water level gauge 48 is mounted in openings in one of the walls'22 and it may include a shut-off valve-49 to facilitate glass removal and cleaning, and protector rods 51 to minimize the chances of glass damage. A thermometer 54 may be installed in an opening in one of the walls 22 so that the temperature of condensation 12 may be read.

In operation, condensate is supplied to tank 20 through a condensate feed opening 42. A switch 44 including a float 46 may be set to automatically start pump 50 when the level of condensation 12 reaches a predetermined height in tank 20.

Pump 50 may comprise any suitable condensation pump, such as, for example, Model Aurora 320, sold by the Aurora Pump Company, North Aurora, Illinois. One skilled in the art will be familiar with the design and the operation of such a pump and a detailed description is therefore deemed unnecessary. It is sufficient to state that a close coupled motor 56 rotates a shaft 58, preferably of stainless steel. An impeller 60, preferably of cast bronze, is keyed to shaft 58. As the motor rotates shaft 58 and impeller 60, condensation 12 enters the pump through supply port 52 and flows through the central opening 62 in the impeller 60. Centrifugal force-causes condensation 12 to leave the impellerand then the pump, through discharge opening 64. As pointed out above, condensation travels from the pump 50 to the desired location, such as boiler 70, through the pipeline 68.

Referring to FIG. 4, there is shown a sectional view of condensate tank 20 with pump 50 mounted thereon, taken along lines 44 of FIG. 3. Walls 22 and of the condensate tank 20 are preferably made of several laminations of woven fiberglass cloth 24 reinforcing epoxy cloth 24 and epoxy resin 26, but it should be understood that

walls

22 and 25 are fabricated entirely in this manner in the preferred embodiment. Further, while a fiberglass reinforcement has been illustrated, the invention is not limited to such. Other materials such as nylon or rayon may be used, but fiberglass is generally preferred because of its strength. The fiberglass reinforcement is preferably a borosilicate composition so as to be highly resistant to hostile environments. The tensile strength of individual glass fibers may, for example, be 500,000 lbs. per square inch and the tensile modulus may be, for example, 10.5 X 10 lbs. per square inch. In addition to being strong, fiberglass is relatively light and relatively inexpensive.

While thereinforcement is preferably of a woven cloth, other forms may be used. For example, a cloth comprising a felted material in which chopped fibers are randomly distributed and held together by a binder may be used, although strength of the finished product is diminished. In addition, the fiberglass may be treated with any suitable commercially available coupling agent to improve the bond between the fiberglass and the epoxy resin.

- Walls 22 are preferably fabricated by laying up successive plies of resin-impregnated reinforcement to the required thickness and turning this assembly into an almost monolithic structure. The reinforcement may be preimpregnated with resin prior to layout, but it is usually easier to position the reinforcement and then apply the resin by brush, roller or by spraying. Each successive ply may be worked with rollers or squeegies to compact the reinforcement, assure proper wetting and remove entrapped air bubbles. The molding process is conventional and further elaboration is not necessary.

There are several commercially available epoxy resins that may be used for the tank walls. It is preferred that the tank when completed have walls with a tensile strength of at least approximately 30,000 lbs. per square inch; a compressive strength of at least approximately 50,000 lbs. per square inch; a flexural strength of at least approximately 30,000 lbs. per square inch; an impact strength of at least approximately 35 footlbs.; and at a relatively low thermal and electric conductivity. One epoxy resin that has proven to be desirable is Thermoset 281, sold by Thermoset Plastics, Inc., Indianapolis, Indiana. This resin sets at room temperature to a dimensionally stable state and when postcured provides high strengths at temperatures up to 275 F. It is low in viscocity and wets fiberglass rapidly. The surface layer may be of a slightly modified epoxy resin, since it is desirable for the surface layer to provide a continuous surface free of voids. A suitable material is Thermoset26l, also sold by Thermoset Plastics, Inc. Any suitable paint pigment may be mixed with the surface coat to make the tank more attractive.

As clearly shown in FIG. 4, walls 22 are manufactured with a groove 23 at their upper end. Top wall 25 conveniently sits in groove 23.

When the walls 22 are fabricated by laying up successive plies of resin, impregnated reinforcement, as explained above, fittings of any suitable material, may be molded into any of the openings in the walls 22 by ap plying resin between the fitting and the walls 22. For example, a polyvinyl chloride fitting 28 may be molded into condensate feed opening 42 to provide a stronger connection between pipeline 74 and tank 20. Couplings may also be used at the openings for the ther mometer 54, gauge 48, etc.

While it has been generally known that condensate tanks of cast iron or steel had shortcomings, those skilled in the art never Conceived of a condensate tank made of a fiberglass reinforced epoxy resin for several reasons. First, it was generally considered that a fiberglass reinforced epoxy resin tank would be too expensive to manufacture. Second, it was thought that such a condensate tank would be likely to soften or melt and thereby cause a failure of the tank. Finally, it is customary for the condensate tank to support the condensate pump and it was generally thought that a condensate tank manufactured of fiberglass reinforced epoxy resin would not have the strength to support a suitable condensate pump.

In accordance with the present invention, a condensate tank 20 is disclosed with a relatively high melting temperature, a relatively low manufacturing cost and sufficient strength to support a suitable condensate pump. Referring to FIG. 5, there is shown a perspective view, partly in cross-section, of one of the walls 22 with a metallic plate, preferably of an aluminum alloy such as Al356 molded therein. The metallic plate has four side faces 33 bonded to the walls 22. The end faces 31 are free from contact with the walls 22. Projecting portions, 35 and 37, extend from at least two of the side faces 33. The projecting portions have a width that is less than the distance between the end faces 31. This reduction in cross-section results in an increase in surface area contacting the epoxy resin and therefore an increase in bond strength. Taps 40 are located in the projecting

portions

35 and 37 so that a condensate pump 50 may be bolted thereto. The condensate tank 20 is capable of supporting condensate pump 50 only because the pump is mounted to metallic plate 30.

The Table below compares several properties of condensate tanks (1) made in accordance with the present invention, (2) made of Class 30 cast iron, and (3) made of low carbon steel. The condensate tank made in accordance with the present invention had a glass content by weight of 60 percent. Each wall consisted of an outer laminate of Thermoset 261, 0.030 inch thick and four layers of Thermoset 281, each 0.055 inch thick with two layers of woven fiberglass mat 0.014 inch thick and two layers 0.070 inch thick embedded therein.

lmpact Tensile Compr. Strength Thermal Strength Strength lZOD Conductivity Material psi psi l0" ft-lb Btu/hr/ft /F/in Fiberglass W/ Epoxy 60 55 50 2 Cast Iron 30 I09 35 460 Steel 55 55 60 320 Thermal Cocff. Flexural Density Electric Of Expansion Strength Material lh/l't Conduct. in/in"F l()' psi l0 Fiberglass/W extremely Epoxy l04 resistant 4 52 Cast Iron 4.50 excellent 6 l0 Steel 484 excellent 6 28 One skilled in the art will realize that there has been disclosed a condensation apparatus including a condensate tank that is resistant to corrosion, lightweight, low in thermal conductivity, relatively simple to maintain, resistant to electrical conduction, and attractive.

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is: I

1. An apparatus for returning condensation to a location comprising:

tank means for receiving and storing said condensa tion,

pump means for returning said condensation from said tank means to said location,

said tank means having walls constructed of a plurality of laminations of fiberglass cloth and epoxy resin,

a metallic plate molded into one of said walls of said tank means, said metallic plate having side faces bonded to said walls and end faces free of contact with said walls, said metallic plate further having projecting portions extending from said side faces, said projecting portions have a width that is less than the distance between said end faces to increase the surface area contacting the epoxy resin and therefore the bond strength, and

mounting means in said projecting portions for mounting said'p'ump means to said tank means so that said tank walls will have enough strength to support said pump means, said pump means being mounted on said mounting means, and said plate having a condensate return opening aligned with a supply port in said pump means so that condensation may be drawn from said tank means to said locations by said pump means.

2. An apparatus as recited in claim 1, further characterized in that said tank means has a plurality of openings in said walls and at least some of said openings have fittings molded therein.

3. An apparatus as recited in claim 2, further characterized in that said fittings are made of polyvinyl chloride.

4. An apparatus as recited in claim 2, further characterized in that said metallic plate is made of an aluminum alloy.

5. An apparatus as recited in claim 2, further characterized in that said fiberglass cloth is woven.

6. An apparatus as recited in claim 2, further characterized in that said walls are constructed of alternate layers of said cloth and said epoxy resin.

7. An apparatus as recited in claim 2, further including shim means beneath the pump means to support said pump means.

8. An apparatus as recited in claim 7, further including sight glass means on one of said walls for visually determining the condensation level in the tank means, float-type switch means for automatically starting said pump means when said condensation level in said tank means reaches a predetermined amount, and temperature sensing means for determining the temperature of the condensation in said tank means.

Claims

2. An apparatus as recited in claim 1, further characterized in that said tank means has a plurality of openings in said walls and at least some of said openings have fittings molded therein.
3. An apparatus as recited in claim 2, further characterized in that said fittings are made of polyvinyl chloride.
4. An apparatus as recited in claim 2, further characterized in that said metallic plate is made of an aluminum alloy.
5. An apparatus as recited in claim 2, further characterized in that said fiberglass cloth is woven.
6. An apparatus as recited in claim 2, further characterized in that said walls are constructed of alternate layers of said cloth and said epoxy resin.
7. An apparatus as recited in claim 2, further including shim means beneath the pump means to support said pump means.
8. An apparatus as recited in claim 7, further including sight glass means on one of said walls for visually determining the condensation level in the tank means, float-type switch means for automatically starting said pump means when said condensation level in said tank means reaches a predetermined amount, and temperature sensing means for determining the temperature of the condensation in said tank means.