US3589141A

US3589141A - Refrigeration apparatus

Info

Publication number: US3589141A
Application number: US810696A
Authority: US
Inventors: Howard E Caswell
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 1969-03-26
Filing date: 1969-03-26
Publication date: 1971-06-29
Anticipated expiration: 1988-06-29

Abstract

Refrigeration apparatus for supplying chilled water at utility quantities including a refrigerant compressor, a plurality of evaporators and a plurality of condensers. A group of the evaporators are interconnected to form a single-flow path for the water flowing in heat transfer relationship with the refrigerant of the system. Track means will be disposed beneath the evaporator and means will be mounted on the evaporators so the evaporators are movably supported on the track means.

Description

United States Patent [72] Inventor Howard E. Caswell Dewitt, N.Y. [,21] Appl. No. 810,696 [22] Filed Mar. 26, 1969 {45] Patented June 29, 1971 [73] Assignee Carrier Corporation Syracuse, N.(.

[54] REFRIGERATION APPARATUS 1 Claim, 2 Drawing Figs.

[52] U.S. C1 62/448, 62/510 62/297, 62/389, 165/78 [51} Int. Cl F25d 19/02 [50] Field of Search 62/510, 297, 448, 389; 165/78 [56] References Cited UNITED STATES PATENTS 115,870 6/1871 Logorce 165/78 2,256,882 9/1941 Sebald 165/78 2,266,107 12/1941 Waterfill 1 l 62/510 2,727,364 l2/l955 Perez i 1. 62/297 3,067,592 12/1962 McFarlan 62/510 3,210,957 10/1965 Rutishauser... 62/448 3,242,686 3/1966 Bowman 62/510 Primary Examiner-William .1. Wye Attorneys-Harry G. Martin, Jr. and l. Raymond Curtin FIG! PATENTEU JUN29 19?:

sum 1 BF 2 INVENTOR. HOWARD E. CASWELL.

ATTORNEY.

PATENIED JUN29 l97| SHEET 2 CF 2 FIG. 2

INVENTUR. HOWARD E. CASWELL -44 M4 M REFRIGERATION APPARATUS BACKGROUND OF THE INVENTION This invention relates to a novel refrigeration apparatus and in particular to such apparatus particularly adaptable for use where chilled water in utility quantities for air conditioning simultaneously a considerable number of buildings will be produced.

It has been envisioned that public utility companies will eventually supply conditioned water for heating and cooling purposes to extensive areas similar to the manner in which they now supply electricity and gas.

From a central plant, water mains will run to each and every block, thereby distributing hot or cold water as is required. It is thought that such a service can be provided at a considerably lower cost and with greater dependability than is possible with present individual heating and cooling systems.

At present, at least one such public utility company is sup plying chilled water for air-conditioning purposes to a sizable group of customers in an extended area.

To maintain the quantity of conditioned water required for utility services, machines of much larger'size, when compared to the machines presently in use even in large commercial plants, must be utilized. Such large machines might be required to be rated at 50,000 tons. Since present machines are generally limited to a maximum of about 5,000 tons, such a substantial increase in size would create many problems.

If a single unit were to be manufactured with a capacity of up to 50,000 tons, a substantial investment in ultra-large machine tools would be necessary. Additionally, severe design distortions would be required in order to ship the excessively large machines via trucks or railroad cars. Furthermore, spare parts would be costly, and repairs and ordinary maintenance would probably require a relatively long inoperable period, which would be extremely undesirable when considering the function of the machine.

Alternatively to manufacturing single giant units, a number of smaller, standard size chillers may be connected together to supply the quantity of chiller water required for utility purposes. The manner in which a plurality of units may be connected or lashed" together for operation as a single unit is well known to those familiar with the art. However, although such an assembly will alleviate much of the tooling and shipping problems hereinabove discussed, repairs would still be time consuming with conventional constructions of condensers and evaporators.

The object of this invention is to alleviate the problems discussed hereinabove by affording novel constructions for refrigeration machinery which will make such apparatus especially adaptable for utility plants or similar large systems wherein a plurality of units will be lashed together for joint operation.

SUMMARY OF THE INVENTION The invention herein disclosed pertains to the novel construction of refrigeration apparatus which will make such apparatus especially useful in large operations where two or more refrigeration units will be interconnected for operation as a single unit."

Generally, two or more large refrigeration compressors will be connected to operate in parallel. The compressors will discharge high-pressure, high-temperature refrigerant gas through large discharge manifolds to a plurality of condensers. The condensers, in order to save space and reduce piping costs, will preferably be supportably mounted on top of the refrigerant evaporators.

Since condensers normally require relatively frequent cleaning, they should be positioned so they are easily accessible. To satisfy this requirement, the condensers are mounted so their horizontal axes are skewed relative to the horizontal axes of the evaporators. This will permit ready access to the water boxes of the condensers simply by removing the end covers thereof. The condensers water lines should be connected in parallel so that individual condensers may be isolated for repair or servicing without necessitating a shutdown of the entire system. Valves would be provided in the refrigerant supply lines to the condensers to isolate a condenser that is to be serviced from the overall refrigerant circuit.

The condensed refrigerant will flow from the condensers to the evaporator upon which a condenser is mounted. A number of the evaporators are preferably connected in series, and two or more series of evaporators-will be connected in parallel. Such arrangements will probably provide maximum heat transfer for most applications. However, the arrangements of the evaporators may be altered if required to maintain maximum heat transfer. The extra waterside pressure drop caused by connecting the evaporators in series in this arrangement is such a small percentage of the total distribution pressure drop that it is completely practical.

Disposed beneath each of the serially connected evaporator groups will be track means. The evaporators will be movably supported on the track means by means mounted on the evaporator, such as flanged wheels. The track means and the associated means mounted on the evaporator will facilitate maintenance and repairs to the evaporators. The track means should exceed the total, length of a group of serially connected evaporators by at least the length of one evaporator.

If an evaporator connected in an intermediate position in a group is required to be cleaned or otherwise repaired, it first must be disconnected from the adjacent evaporators on either end. Next an overhead crane will lift the entire evaporator structure and deposit it on the length of the unused track means. One section of the remaining evaporators will be slidably moved along the track means to the other section of evaporators and the two sections will be connected. Without the track means, the evaporators would normally be securely mounted to the floor or other stationary supporting means. Repairs could not be made to an evaporator in an intermediate position in a serially connected group of evaporators without shutting down the group for the total length of time necessary to effectuate the repair. Alternatively, extensive and costly piping would be required to bypass any evaporator requiring repair or cleaning.

The invention disclosed herein will facilitate the repair and maintenance of a plurality of interconnected refrigeration units and, in addition, will reduce the costs of making such repairs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of a plurality of refrigeration units interconnected for joint operation, the units being slidably mounted on track means; and

FIG. 2 is an end view of the refrigeration units mounted on the track means.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is illustrated a preferred embodiment of the invention herein disclosed wherein like numerals will refer to like parts.

The refrigeration apparatus illustrated in the accompanying drawings is designed to supply chilled water in quantities sufficient to provide air conditioning to extensive areas. Such an application would be the distribution of chilled water for airconditioning purposes by a public utility company, similar to the manner in which such a company supplies gas or electrici ty.

Specifically, a steam turbine 12 or other power source such as an electrical motor is connected to simultaneously operate refrigeration compressors 10 and 11 connected to operate in parallel. It should be understood that although the compressors are connected to be driven simultaneously, it is within the scope of this invention for the compressors to have individual drives. Additionally, although two compressors are used in a preferred embodiment, the number of compressors can be increased or decreased depending upon the requirements of each installation. Furthermore, it is within the scope of the in vention for the compressors to operate in series, or in seriesparallel combinations, as is well known in the art.

High-temperature, high-pressure refrigerant gas is discharged from the compressors l and 11 by

lines

13 and 14 into discharge manifolds l and 16. The discharge manifolds l5 and 16 are substantially large pipes connecting the refrigerant compressors to a plurality of refrigerant condensers. Each of the compressors and 11 supply the high-pressure refrigerant gas to a plurality or group of condensers. As shown, the two groups of condensers of the embodiment are connected to operate in parallel. A plurality of smaller conduits 17 connect the discharge manifolds l5 and 16 to the plurality of

refrigerant condensers

18, 18a, 18b, 18c, and 19, 19a, 19b, and 190.

The refrigerant gas passes through the condensers in heat transfer relation with a relatively low-temperature medium such as water. The water absorbs heat from the refrigerant gas, thereby condensing the gas into a refrigerant liquid. Main

water supply headers

20 and 24 for delivering water to the condensers are connected to each of the condensers by relatively small conduits 21. Conduits 21 are connected in parallel in each group of condensers for a reason to be explained more fully hereinafter. Discharge lines 22 from each of the condensers deliver the warmed heat transfer medium to discharge vheaders 23 and 25. The warmed water is then either cooled for reuse as a heat transfer medium or is discharged entirely from the system.

The liquid refrigerant flows from the condensers to a plurality of

evaporators

26, 26a, 26b, 26c, and 27, 27a, 27b, and 270 through a float valve 29 disposed therebetween. The float valves 29 regulate the flow of liquid refrigerant to the evaporators. It should be understood that economizers or other intermediate flash coolers may be utilized in lieu of the float valve 29. Each evaporator comprises a substantially cylindrical outer shell or housing 41 defining an inner chamber 42. Disposed within the inner chamber 42 are a plurality of tubular means 43. The inner surface of the tubular means 43 defines a flow path for one medium flowing through the evaporators. A second flow path for a second medium is defined by the outer surface of the tubular means 43 and the inner surface of the housing 41. The liquid refrigerant will pass through the evaporators, by being directed through one of the flow paths, in heat transfer relation with a medium to be cooled such as water, which passes through the evaporators via the other flow path. The liquid refrigerant will absorb heat from the water, causing the refrigerant to vaporize and the water to be cooled as desired. The gaseous refrigerant will then be returned to the compressors 10 and 11 via evaporator discharge lines 30 connected to the

compressor suction headers

31 and 33, thus completing the basic refrigeration cycle.

The plurality of evaporators will be divided into several groups. The evaporators comprising each group of a preferred embodiment will be serially connected via connecting means such as flanged pipes 28. The water to be chilled is supplied to the evaporators via evaporator supply header 32. The water after having been cooled in the evaporators is delivered to the areas being served by discharge main 34 which will supply the water to smaller conduits for eventual delivery to the areas being served.

Groups of evaporators will be serially connected as shown so a single-flow path is provided through each group for the water being cooled. The water will be progressively cooled as it passes through each of the evaporators comprising a group. The arrangement will enable extremely large quantities of water to be sufficiently cooled for conditioning the large number of areas being served.

To save piping and foundation costs and reduce the space required for the refrigeration apparatus, the condensers should be preferably mounted on an associated evaporator. As

is seen in FIG. 2, the condensers can be supportably mounted by means such as beams or supports 35. Preferably, the horizontal axes of the condensers will be skewed relative to the horizontal axes of the evaporators. This will provide easy access to the

water boxes

36 and 37 of the condensers. Since condensers are the apparatus that most require major maintenance in a refrigeration cycle, it is a highly desirable feature of the invention disclosed herein that the condensers be readily accessible for such maintenance.

As noted hereinbefore, the water supply and return lines to the condensers are usually connected in parallel. Thus, by shutting off appropriate refrigerant valves (not shown), any condenser can be isolated when maintenance is required without necessitating the shutdown of an entire group of condensers and evaporators.

As also noted hereinbefore, the refrigeration system shown is designed specifically for installations requiring large capacities of conditioning effect. Since it is conceivable that the requirements will increase, means should be available so that additional apparatus can be readily added to the system when necessary. Additionally, since the evaporators are serially connected, means should be available to expedite evaporator repairs, since maintenance to any one evaporator will necessitate the shutdown of the group of serially connected evaporators.

To obtain these desirable characteristics, track means 38 are disposed beneath each of the evaporator groups. Mounted beneath each of the evaporators and engaging the track means 38 are means such as flanged wheels 39 so the evaporators are movably supported on the track means 38. An evaporator at one end of each group, for

example evaporators

26 and 27, should be firmly held in place by means such as anchor 40 shown in FIG. 2. However, the flanged wheels 39 should be free to roll slightly to accommodate the substantial linear contractions that will occur due to the quantity of relatively cold water that will be flowing through the serially connected evaporators. Additionally, there should be some flexible lengths of piping in the chilled water circuit to accommodate linear contractions in the piping.

If an evaporator in an intermediate position in a group, for example 26b, requires maintenance such as retubing, the flanged piping section 28 on either side of the evaporator will first be disconnected. Refrigerant lines to and from the evaporator would be closed off by valves (not shown). It is of course understood the entire group of evaporators will have been shut down prior to the commencement of any repairs. After appropriate piping, such as the chilled water header 33 and the discharge manifold 15 have been disconnected, the connected evaporators at one end of the evaporator requiring maintenance will be moved along the track means 38 in the direction of the unanchored evaporator. The evaporator 26b requiring maintenance can then be lifted as a unit by means such as overhead cranes (not shown). The evaporator will be set down on an extra or normally unused portion of track means 38 where the required maintenance willbe conducted. The remaining evaporators and condensers will be reassembled along with the piping that required disassembly before the evaporator requiring maintenance could be removed from the group. Thus, any maintenance or repairs required for the evaporators of the system will not keep a group of evaporators shut down for a prolonged period of time. The entire system will be reoperating in a minimum amount of time. By utilizing track means 38, a minimal amount of piping need be disassembled before any one evaporator can be removed from a group for repairs.

While I have described and illustrated a preferred embodiment of my invention, it should be understood that my invention is not limited thereto, since it may be otherwise embodied within the scope of the following claims.

lclaim:

l. Refrigeration apparatus comprising:

a. refrigerant compression means having a suction and a discharge side;

b. a plurality of refrigerant condensers;

with the refrigerant of said apparatus;

f. means for supportably mounting each of said condensers on top of an associated evaporator, the horizontal axis of such condensers being at a skew angle relative to the horizontal axis of said cvaporators;

g. track means disposed beneath said evaporators; and

h. means mounted on said cvaporators so said evaporators are movably supported on said track means.

Claims

1. Refrigeration apparatus comprising: a. refrigerant compression means having a suction and a discharge side; b. a plurality of refrigerant condensers; c. first manifold means connecting the discharge side of said compression means to the inlet of said condensers; d. a plurality of refrigerant evaporators having water flowing therethrough; e. second manifold means connecting at least a part of said plurality of evaporators to said suction side of said compression means, said part of said evaporators being interconnected to form a single flow path for the water flowing through said evaporators in heat transfer relationship with the refrigerant of said apparatus; f. means for supportably mounting each of said condensers on top of an associated evaporator, the horizontal axis of such condensers being at a skew angle relative to the horizontal axis of said evaporators; g. track means disposed beneath said evaporators; and h. means mounted on said evaporators so said evaporators are movably supported on said track means.