US5214925A
Expired / Lapsed
US
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Use of liquified compressed gases as a refrigerant to suppress cavitation and compressibility when pumping liquified compressed gases
Assignee: Union Carbide Chemicals and Plastics Technology LLC
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Filing: 1991-09-30
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Granted: 1993-06-01
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Expires: 2011-09-30
Abstract
Abstract Methods and apparatus for economically and effectively using a portion of a liquified compressed gas feedstock, such as liquid carbon dioxide, as a refrigerant to cool said liquified compressed gas feedstock so as to prevent cavitation and liquid compressibility when pumping such feedstock are disclosed.
Inventors
- 👤 Kenneth L. Hoy
- 👤 Kenneth A. Nielsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:04
CPC Classifications
F; F17; F17C; F17C7/00; F17C7/02; F04; F04B; F04B15/00; F04B15/06; F17C2205/00; F17C2205/03; F17C2205/0302; F17C2205/0323; F17C2205/0332; F17C2205/0338; F17C2221/00; F17C2221/01; F17C2221/013; F17C2223/00; F17C2223/01; F17C2223/0107; F17C2223/0115; F17C2223/0146; F17C2223/0153; F17C2223/03; F17C2223/035; F17C2227/00; F17C2227/01; F17C2227/0128; F17C2227/0135; F17C2227/03; F17C2227/0337; F17C2227/0367; F17C2227/0388; F17C2260/00; F17C2260/02; Y; Y10; Y10S; Y10S417/00; Y10S417/901
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
152 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; and b) sufficiently cooling the first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such first liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas, said adiabatic direct expansion being such that the temperature and pressure of the second at least one liquified compressed gas are not below its triple point.
Claim 2
Independent Claim
152 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; and b) sufficiently cooling the first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such first liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas, said adiabatic direct expansion being such that the temperature and pressure of the second at least one liquified compressed gas are not below its triple point.
Claim 3
Dependent Claim
26 words
The method of claim 1, wherein the second at least one liquified compressed gas is a portion of the first at least one liquified compressed gas.
Claim 4
Dependent Claim
26 words
The method of claim 2, wherein the liquified compressed gas is liquid carbon dioxide having a triple point of about -57° C. and about 75 psia.
Claim 5
Dependent Claim
35 words
The method of claim 1, wherein the first at least one liquified compressed gas is comprised of liquid nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 6
Dependent Claim
41 words
The method of claim 1, wherein the first at least one liquified compressed gas is comprised of a liquid mixture of carbon dioxide and nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 7
Dependent Claim
53 words
The method of claim 1, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 8
Dependent Claim
31 words
The method of claim 1, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at about -18° C. and about 300 psig.
Claim 9
Dependent Claim
53 words
The method of claim 1, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 10
Dependent Claim
34 words
The method of claim 1, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide at a temperature of about -18° C. and a pressure of about 300 psig.
Claim 11
Independent Claim
138 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying the at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; and b) sufficiently cooling the at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such liquified compressed gas by allowing a portion of such liquified compressed gas to undergo adiabatic direct expansion while it is in indirect heat exchange relationship with the remaining liquified compressed gas, said adiabatic direct expansion being such that the temperature and pressure of the at least one liquified compressed gas are not below its triple point.
Claim 12
Independent Claim
138 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying the at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; and b) sufficiently cooling the at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such liquified compressed gas by allowing a portion of such liquified compressed gas to undergo adiabatic direct expansion while it is in indirect heat exchange relationship with the remaining liquified compressed gas, said adiabatic direct expansion being such that the temperature and pressure of the at least one liquified compressed gas are not below its triple point.
Claim 13
Dependent Claim
19 words
The method of claim 10, wherein the at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 14
Independent Claim
221 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) measuring the temperature of the cooled first at least one liquified compressed gas and generating at least one signal in response to such measurement; d) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (c) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof; and e) pumping the cooled first at least one liquified compressed gas.
Claim 15
Independent Claim
221 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) measuring the temperature of the cooled first at least one liquified compressed gas and generating at least one signal in response to such measurement; d) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (c) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof; and e) pumping the cooled first at least one liquified compressed gas.
Claim 16
Dependent Claim
26 words
The method of claim 12, wherein the second at least one liquified compressed gas is a portion of the first at least one liquified compressed gas.
Claim 17
Dependent Claim
26 words
The method of claim 13, wherein the liquified compressed gas is liquid carbon dioxide having a triple point of about -57° C. and about 75 psia.
Claim 18
Dependent Claim
35 words
The method of claim 12, wherein the first at least one liquified compressed gas is comprised of liquid nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 19
Dependent Claim
41 words
The method of claim 12, wherein the first at least one liquified compressed gas is comprised of a liquid mixture of carbon dioxide and nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 20
Dependent Claim
53 words
The method of claim 12, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 21
Dependent Claim
31 words
The method of claim 12, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at about -18° C. and about 300 psig.
Claim 22
Dependent Claim
53 words
The method of claim 12, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 23
Dependent Claim
34 words
The method of claim 12, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide at a temperature at about -18° C. and a pressure of about 300 psig.
Claim 24
Independent Claim
239 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) pumping the cooled first at least one liquified compressed gas at a pumping flow rate; d) measuring the pumping flow rate of the first at least one liquified compressed gas and generating at least one signal in response to such measurement; e) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (d) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof; and f) pumping the sufficiently cooled first at least one liquified compressed gas.
Claim 25
Independent Claim
239 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) pumping the cooled first at least one liquified compressed gas at a pumping flow rate; d) measuring the pumping flow rate of the first at least one liquified compressed gas and generating at least one signal in response to such measurement; e) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (d) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof; and f) pumping the sufficiently cooled first at least one liquified compressed gas.
Claim 26
Dependent Claim
27 words
The method of claim 21, wherein the pumping flow rate of the first at least one liquified compressed gas is measured by using a mass flow meter.
Claim 27
Dependent Claim
26 words
The method of claim 21, wherein the second at least one liquified compressed gas is a portion of the first at least one liquified compressed gas.
Claim 28
Dependent Claim
26 words
The method of claim 21, wherein the liquified compressed gas is liquid carbon dioxide having a triple point of about -57° C. and about 75 psia.
Claim 29
Dependent Claim
35 words
The method of claim 21, wherein the first at least one liquified compressed gas is comprised of liquid nitrous oxide and the second at last one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 30
Dependent Claim
41 words
The method of claim 21, wherein the first at least one liquified compressed gas is comprised of a liquid mixture of carbon dioxide and nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 31
Dependent Claim
53 words
The method of claim 21, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 32
Dependent Claim
31 words
The method of claim 21, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at about -18° C. and about 300 psig.
Claim 33
Dependent Claim
53 words
The method of claim 21, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 34
Dependent Claim
34 words
The method of claim 21, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide at a temperature at about -18° C. and a pressure of about 300 psig.
Claim 35
Independent Claim
231 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) pumping the cooled first at least one liquified compressed gas to at least one spray gun that sprays the at least one liquified compressed gas; d) spraying the first at least one liquified compressed gas and generating at least one signal in response to such spraying; e) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (d) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof.
Claim 36
Independent Claim
231 words
A method for helping to prevent cavitation and liquid compressibility when pumping at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C. comprising: a) supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at STP conditions; b) cooling the first at least one liquified compressed gas by the adiabatic direct expansion of a second at least one liquified compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) pumping the cooled first at least one liquified compressed gas to at least one spray gun that sprays the at least one liquified compressed gas; d) spraying the first at least one liquified compressed gas and generating at least one signal in response to such spraying; e) supplying the second at least one liquified compressed gas as the refrigerant for cooling step (b) in response to the at least one signal generated in step (d) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and the temperature and pressure of the second at least one liquified compressed gas is maintained above its triple point during the adiabatic direct expansion thereof.
Claim 37
Dependent Claim
26 words
The method of claim 31, wherein the second at least one liquified compressed gas is a portion of the first at least one liquified compressed gas.
Claim 38
Dependent Claim
26 words
The method of claim 31, wherein the liquified compressed gas is liquid carbon dioxide having a triple point of about -57° C. and about 75 psia.
Claim 39
Dependent Claim
35 words
The method of claim 31, wherein the first at least one liquified compressed gas is comprised of liquid nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 40
Dependent Claim
41 words
The method of claim 31, wherein the first at least one liquified compressed gas is comprised of a liquid mixture of carbon dioxide and nitrous oxide and the second at least one liquified compressed gas is comprised of liquid carbon dioxide.
Claim 41
Dependent Claim
53 words
The method of claim 31, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 42
Dependent Claim
31 words
The method of claim 31, wherein the first at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at about -18° C. and about 300 psig.
Claim 43
Dependent Claim
53 words
The method of claim 31, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide and is supplied at a pressure in the range of from about 250 to about 900 psig and at a temperature in the range of from about -25° C. to about 24° C.
Claim 44
Dependent Claim
34 words
The method of claim 31, wherein the second at least one liquified compressed gas is comprised of liquid carbon dioxide at a temperature at about -18° C. and a pressure of about 300 psig.
Claim 45
Independent Claim
162 words
An apparatus for helping to prevent cavitation and liquid compressibility when pumping liquified compressed gases comprising: a) means for supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C.; b) means for sufficiently cooling the first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such first liquified compressed gas by the adiabatic direct expansion of a second at least one liquid compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) means for controlling the adiabatic direct expansion of the second at least one liquified compressed gas such that its temperature and pressure are maintained above its triple point; and d) means for pumping the cooled first at least one liquified compressed gas.
Claim 46
Independent Claim
162 words
An apparatus for helping to prevent cavitation and liquid compressibility when pumping liquified compressed gases comprising: a) means for supplying a first at least one liquified compressed gas which is to be pumped, said liquified compressed gas being a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C.; b) means for sufficiently cooling the first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such first liquified compressed gas by the adiabatic direct expansion of a second at least one liquid compressed gas which is a gas at STP conditions and which is in indirect heat exchange relationship with the first at least one liquified compressed gas; c) means for controlling the adiabatic direct expansion of the second at least one liquified compressed gas such that its temperature and pressure are maintained above its triple point; and d) means for pumping the cooled first at least one liquified compressed gas.
Claim 47
Independent Claim
244 words
An apparatus for helping to prevent cavitation and liquid compressibility when pumping liquified compressed gases comprising: a) means for supplying a first at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C.; b) means for supplying a second at least one liquified compressed gas which is a gas at STP conditions; c) heat exchange means for cooling the first at least one liquified compressed gas by the adiabatic direct expansion of the second at least one liquified compressed gas which is in indirect heat exchange relationship with the first at least one liquified compressed gas; d) means for pumping the first at least one liquified compressed gas cooled in step (c); e) means for generating at least one signal indicative of the further cooling required of the cooled first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such cooled first liquified compressed gas; f) means for regulating the supply of the second at least one liquified compressed gas as the refrigerant for cooling step (c) in response to the at least one signal generated in step (e) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and to maintain the temperature and pressure of the second at least one liquified compressed gas above its triple point during the adiabatic direct expansion thereof.
Claim 48
Independent Claim
244 words
An apparatus for helping to prevent cavitation and liquid compressibility when pumping liquified compressed gases comprising: a) means for supplying a first at least one liquified compressed gas which is a gas at standard temperature and pressure conditions (STP) of 1 atmosphere and 0° C.; b) means for supplying a second at least one liquified compressed gas which is a gas at STP conditions; c) heat exchange means for cooling the first at least one liquified compressed gas by the adiabatic direct expansion of the second at least one liquified compressed gas which is in indirect heat exchange relationship with the first at least one liquified compressed gas; d) means for pumping the first at least one liquified compressed gas cooled in step (c); e) means for generating at least one signal indicative of the further cooling required of the cooled first at least one liquified compressed gas so as to substantially prevent cavitation and liquid compressibility of such cooled first liquified compressed gas; f) means for regulating the supply of the second at least one liquified compressed gas as the refrigerant for cooling step (c) in response to the at least one signal generated in step (e) such that the first at least one liquified compressed gas is sufficiently cooled to help prevent cavitation and liquid compressibility and to maintain the temperature and pressure of the second at least one liquified compressed gas above its triple point during the adiabatic direct expansion thereof.
Claim 49
Dependent Claim
31 words
The apparatus of claim 41, wherein the first at least one liquified compressed gas comprises liquid carbon dioxide and the means for supplying such liquid carbon dioxide comprises a supply vessel.
Claim 50
Dependent Claim
36 words
The apparatus of claim 41, wherein the heat exchange means comprises shell-and-tube-type heat exchangers selected from the group consisting of fixed-tube-sheet, U-tube, floating head, divided flow, split flow, bayonet tube, spiral-tube and spiral-plate type heat exchangers.
Claim 51
Dependent Claim
58 words
The apparatus of claim 41, wherein the heat exchange means for cooling the first at least one liquified compressed gas comprises an external conduit or tube in thermal contact with the line connecting the supply means of the first liquified compressed gas to the pumping means and through which the second at least one liquified compressed gas flows.
Claim 52
Dependent Claim
41 words
The apparatus of claim 41, wherein the heat exchange means for cooling the first at least one liquified compressed gas comprises a double-pipe heat exchanger in line connecting the supply means of the first liquified compressed gas and the pumping means.
Claim 53
Dependent Claim
35 words
The apparatus of claim 41, wherein the heat exchange means for cooling the first at least one liquified compressed gas comprises an external coil fitted to the contour of the head of the pumping means.
Claim 54
Dependent Claim
25 words
The apparatus of claim 41, wherein the means for pumping the cooled first at least one liquified compressed gas comprises a double-acting, four-check-valve reciprocating pump.
Claim 55
Dependent Claim
27 words
The apparatus of claim 41, wherein the means for pumping the cooled first at least one liquified compressed gas comprises an air driven double-acting, four-check-valve reciprocating pump.
Claim 56
Dependent Claim
31 words
The apparatus of claim 41, wherein the means for pumping the cooled first at least one liquified compressed gas comprises an air driven, single-acting reciprocating pump having a three-way cycling spool.
Claim 57
Dependent Claim
38 words
The apparatus of claim 41, wherein the first and second liquified gases are the same and the means for supplying the first liquified compressed gas is the same as the means for supplying the second liquified compressed gas.
Claim 58
Dependent Claim
32 words
The apparatus of claim 41, wherein the first and second liquified gases are the same and the supply means (b) is comprised of a supply line communicating with the supply means (a).
Claim 59
Dependent Claim
52 words
The apparatus of claim 41, wherein the means for regulating the supply of the second at least one liquified compressed gas as the refrigerant for cooling step (c) above its triple point comprises a pressure regulator, or a temperature monitor and controller, or a variable orifice control valve, or a combination thereof.
Claim 60
Dependent Claim
60 words
The method of claim 41, wherein the means for generating at least one signal which indicates the relative degree of cooling required of the first at least one liquified compressed gas comprises means for measuring the temperature of the cooled first at least one liquified compressed gas and means for generating at least one signal in response to such measurement.
Claim 61
Dependent Claim
63 words
The apparatus of claim 41, wherein the means for generating at least one signal which indicates the relative degree of cooling required of the first at least one liquified compressed gas comprises means for measuring the pumping rate or flow rate of the first at least one liquified compressed gas and means for generating at least one signal in response to such measurement.
Claim 62
Dependent Claim
58 words
The apparatus of claim 54, wherein the means for measuring the flow rate of the first at least one liquified compressed gas comprises a mass flow meter means used to proportion the first at least one liquified compressed gas with coating material for spray application and means for generating at least one signal in response to such measurement.
Claim 63
Dependent Claim
67 words
The apparatus of claim 41, wherein the means for generating at least one signal which indicates the relative degree of cooling required of the first at least one liquified compressed gas comprises means for activating at least one spray gun that sprays the first at least one liquified compressed gas mixed with coating material and means for generating at least one signal in response to such activation.
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