US3894832A
Expired / Lapsed
US
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Heat-input-controlled gas-fired equipment and method
Assignee: Chevron USA Inc
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Filing: 1973-10-01
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Granted: 1975-07-15
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Expires: 1993-10-01
Abstract
Abstract Gas-fired equipment comprising a heater having at least one burner and a fuel gas feed line containing a main fuel gas control valve or orifice, and a control system including a compensator designed to prevent changes in heating value of a fuel gas from upsetting the heat input rate to the equipment is disclosed. The compensator is fed signals representing: (1) the pressure P of the fuel gas, and (2) the specific gravity of the fuel gas, G. The compensator then relates these signals so that the heat input rate q is maintained substantially constant in spite of variations in the fuel gas heating value. The relationship established in the compensator is Q/K F(P,G) (1) where: Q THE HEAT INPUT RATE, K a flow capacity coefficient, P a pressure in the fuel gas system, and G the specific gravity of the fuel gas. The function q/K is maintained substantially constant by preferably varying the pressure P in response to changes in the fuel gas specific gravity, G. Thus, for any given value of K the heat input rate, q, to the gas-fired equipment is maintained substantially constant. By means of the present invention, upsets in process fluid temperature or heat input rate due to changes in fuel gas heating value are eliminated and more efficient operation of the equipment is maintained.
Inventors
- 👤 Thomas G Chin
- 👤 Ronald C Sorensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:30
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/022
Claims Analysis
Total Claims: 70
Claim 1
Independent Claim
107 words
A method for preventing upsets in heat input rate to fuel gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a burner and a fuel gas feed line containing a main fuel gas control valve or orifice wherein critical flow is maintained, which comprises adjusting the value of at least P1 and as required to maintain substantially constant the quantity q/K in the equation q/K f(P1,G) Wherein q heat input rate, K main fuel gas control valve or orifice flow capacity coefficient, P1 pressure upstream of the main fuel gas control valve or orifice, and G specific gravity of the fuel gas.
Claim 2
Independent Claim
107 words
A method for preventing upsets in heat input rate to fuel gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a burner and a fuel gas feed line containing a main fuel gas control valve or orifice wherein critical flow is maintained, which comprises adjusting the value of at least P1 and as required to maintain substantially constant the quantity q/K in the equation q/K f(P1,G) Wherein q heat input rate, K main fuel gas control valve or orifice flow capacity coefficient, P1 pressure upstream of the main fuel gas control valve or orifice, and G specific gravity of the fuel gas.
Claim 3
Dependent Claim
9 words
establishing a second signal representative of the pressure P1:
Claim 4
Dependent Claim
9 words
establishing a second signal representative of the pressure P1:
Claim 5
Dependent Claim
8 words
The method of claim 1 further characterized by:
Claim 6
Dependent Claim
9 words
said second means is a pressure sensor and transmitter.
Claim 7
Dependent Claim
9 words
said second means is a pressure sensor and transmitter.
Claim 8
Dependent Claim
10 words
said second means is a pressure sensor and transmitter; and
Claim 9
Dependent Claim
10 words
said second means is a pressure sensor and transmitter; and
Claim 10
Dependent Claim
26 words
a second means to establish a second signal representative of the pressure P1 in said line upstream of said main fuel gas control valve or orifice;
Claim 11
Dependent Claim
26 words
a second means to establish a second signal representative of the pressure P1 in said line upstream of said main fuel gas control valve or orifice;
Claim 12
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P1 in said first portion;
Claim 13
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P1 in said first portion;
Claim 14
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P2 in said second portion;
Claim 15
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P2 in said second portion;
Claim 16
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P1 in said first portion;
Claim 17
Dependent Claim
17 words
a second means to establish a second signal representative of the pressure P1 in said first portion;
Claim 18
Dependent Claim
13 words
establishing a second signal representative of the pressure P1 in said fist portion:
Claim 19
Dependent Claim
13 words
establishing a second signal representative of the pressure P1 in said fist portion:
Claim 20
Dependent Claim
9 words
establishing a second signal representative of the pressure P2:
Claim 21
Dependent Claim
9 words
establishing a second signal representative of the pressure P2:
Claim 22
Dependent Claim
16 words
functionally relating said first and said second signals in accordance with the equation C f(P2,G) and
Claim 23
Dependent Claim
16 words
functionally relating said first and said second signals in accordance with the equation C f(P2,G) and
Claim 24
Dependent Claim
17 words
The method of claim 2 wherein C P1 (G+k) wherein k an adjustable constant, and C q/K.
Claim 25
Dependent Claim
13 words
establishing a third signal representative of the pressure P2 in said second portion:
Claim 26
Dependent Claim
13 words
establishing a third signal representative of the pressure P2 in said second portion:
Claim 27
Dependent Claim
18 words
a third means to establish a third signal representative of the pressure P2 in said second portion; and
Claim 28
Dependent Claim
18 words
a third means to establish a third signal representative of the pressure P2 in said second portion; and
Claim 29
Dependent Claim
52 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation C f(P1,G) wherein C q/K2, q heat input rate, and K2 main fuel gas control value flow capacity coefficient, and b. responsive to changes in P1 or G maintain said C substantially constant.
Claim 30
Dependent Claim
52 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation C f(P1,G) wherein C q/K2, q heat input rate, and K2 main fuel gas control value flow capacity coefficient, and b. responsive to changes in P1 or G maintain said C substantially constant.
Claim 31
Dependent Claim
48 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation C f(P2,G) wherein C q/K2, q heat input rate, and K2 burner flow capacity coefficient, and (b) responsive to changes in P2 or G maintain said C substantially constant.
Claim 32
Dependent Claim
48 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation C f(P2,G) wherein C q/K2, q heat input rate, and K2 burner flow capacity coefficient, and (b) responsive to changes in P2 or G maintain said C substantially constant.
Claim 33
Dependent Claim
50 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation q/K f(P1,G) wherein q heat input rate, and K main fuel gas control valve flow capacity coefficient, and b. responsive to changes in P1 or G maintain said q/K substantially constant.
Claim 34
Dependent Claim
50 words
a third means to a. functionally relate said first signal and said second signal in accordance with the equation q/K f(P1,G) wherein q heat input rate, and K main fuel gas control valve flow capacity coefficient, and b. responsive to changes in P1 or G maintain said q/K substantially constant.
Claim 35
Dependent Claim
9 words
said third means is a pressure sensor and transmitter.
Claim 36
Dependent Claim
9 words
said third means is a pressure sensor and transmitter.
Claim 37
Dependent Claim
16 words
functionally relating said first and said second signals in accordance with the equation q/K f(P1,G) and
Claim 38
Dependent Claim
16 words
functionally relating said first and said second signals in accordance with the equation q/K f(P1,G) and
Claim 39
Dependent Claim
56 words
a fourth means to a. functionally relate said first signal, said second signal, and said third signal in accordance with the equation q/K f(P1,P2,G) wherein q heat input rate, and K main fuel gas control valve or orifice flow capacity coefficient, and b. responsive to changes in P1, P2 or G maintain saiD q/K substnatially constant.
Claim 40
Dependent Claim
56 words
a fourth means to a. functionally relate said first signal, said second signal, and said third signal in accordance with the equation q/K f(P1,P2,G) wherein q heat input rate, and K main fuel gas control valve or orifice flow capacity coefficient, and b. responsive to changes in P1, P2 or G maintain saiD q/K substnatially constant.
Claim 41
Dependent Claim
37 words
functionally relating the signals G, P1 and P2 in accordance with the equation q/K f(P1,P2,G) wherein q heat input rate, K main fuel gas control valve or orifice flow capacity coefficient; and maintaining said q/K substantially constant.
Claim 42
Dependent Claim
37 words
functionally relating the signals G, P1 and P2 in accordance with the equation q/K f(P1,P2,G) wherein q heat input rate, K main fuel gas control valve or orifice flow capacity coefficient; and maintaining said q/K substantially constant.
Claim 43
Dependent Claim
7 words
adjusting P1 to maintain q/K substantially constant.
Claim 44
Dependent Claim
7 words
adjusting P1 to maintain q/K substantially constant.
Claim 45
Independent Claim
96 words
A method fOr preventing upsets in heat input rate to fuel gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a burner and a fuel gas feed line containing a main fuel gas control valve or orifice, which comprises adjusting the value of P2 and as required to maintain substantially constant the quantity C in the equation C f(P2,G) wherein C q/K q heat input rate, K burner flow capacity coefficient, P2 pressure downstream of the main fuel gas control valve or orifice, and G specific gravity of the fuel gas.
Claim 46
Independent Claim
96 words
A method fOr preventing upsets in heat input rate to fuel gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a burner and a fuel gas feed line containing a main fuel gas control valve or orifice, which comprises adjusting the value of P2 and as required to maintain substantially constant the quantity C in the equation C f(P2,G) wherein C q/K q heat input rate, K burner flow capacity coefficient, P2 pressure downstream of the main fuel gas control valve or orifice, and G specific gravity of the fuel gas.
Claim 47
Dependent Claim
7 words
adjusting P2 to maintain q/K substantially constant.
Claim 48
Dependent Claim
7 words
adjusting P2 to maintain q/K substantially constant.
Claim 49
Dependent Claim
8 words
The method of claim 4 further characterized by:
Claim 50
Dependent Claim
13 words
The method of claim 5 wherein C P2(G+k) wherein k an adjustable constant.
Claim 51
Dependent Claim
6 words
The method of claim 6 wherein
Claim 52
Independent Claim
66 words
A method for preventing upsets in the heat input rate to gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a fuel gas feed line comprised of a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, comprising:
Claim 53
Independent Claim
66 words
A method for preventing upsets in the heat input rate to gas-fired equipment wherein the fuel gas fluctuates in heating value and said equipment comprises a fuel gas feed line comprised of a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, comprising:
Claim 54
Dependent Claim
79 words
In a fuel gas fired heating system comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas fluctuates in heating value and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, the improvement which comprises:
Claim 55
Dependent Claim
79 words
In a fuel gas fired heating system comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas fluctuates in heating value and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, the improvement which comprises:
Claim 56
Dependent Claim
48 words
The system of claim 9, wherein said fourth means comprises a fuel gas heating value compensator system operating an inlet control valve, said inlet control valve positioned in said fuel gas feed line upstream of the point at which said second means establishes the signal representative of P1.
Claim 57
Dependent Claim
9 words
The fuel gas-fired heating system of claim 1 wherein:
Claim 58
Dependent Claim
61 words
In a fuel gas fired heating system comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas fluctuates in heating value and wherein said fuel gas feed line to said heating system comprises a line containing a main fuel gas control valve or orifice wherein critical flow is maintained, the improvement comprising:
Claim 59
Dependent Claim
61 words
In a fuel gas fired heating system comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas fluctuates in heating value and wherein said fuel gas feed line to said heating system comprises a line containing a main fuel gas control valve or orifice wherein critical flow is maintained, the improvement comprising:
Claim 60
Dependent Claim
71 words
The system of claim 12 wherein said third means comprises a fuel gas heating value compensator system operating an inlet control valve, said inlet control valve positioned in said fuel gas feed line upstream of the point at which said second means establishes said signal representative of P1, and said inlet control valve is operated by said fuel gas heating value compensator system to adjust P1 responsive to changes in G.
Claim 61
Dependent Claim
36 words
The fuel gas fired heating system of claim 13 wherein q/CgK'' P1 (G+B/A), K'' a constant, Cg main fuel gas control value or orifice flow coefficient for critical flow, B a constant, and A a constant.
Claim 62
Dependent Claim
10 words
The fuel gas fired heating system of claim 14 wherein:
Claim 63
Dependent Claim
79 words
A fuel gas fired heating system wherein the fuel gas fluctuates in heating value, comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, and a control system which comprises:
Claim 64
Dependent Claim
79 words
A fuel gas fired heating system wherein the fuel gas fluctuates in heating value, comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, and a control system which comprises:
Claim 65
Dependent Claim
17 words
The fuel gas-fired heating system of claim 8 wherein: C P2 (G+k) wherein k an adjustable constant.
Claim 66
Dependent Claim
9 words
The fuel gas-fired heating system of claim 17 wherein:
Claim 67
Dependent Claim
79 words
A fuel gas fired heating system wherein the fuel gas fluctuates in heating value, comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, and a control system which comprises:
Claim 68
Dependent Claim
79 words
A fuel gas fired heating system wherein the fuel gas fluctuates in heating value, comprising a heater having at least one burner and a fuel gas feed line, and wherein said fuel gas feed line to said heating system comprises a first and a second portion, said first portion being upstream of said second portion and said first and said second portions being separated by a main fuel gas control valve or orifice, and a control system which comprises:
Claim 69
Dependent Claim
60 words
The system of claim 11 further comprised of an inlet control valve positioned in said fuel gas feed line upstream of the point at which said second means establishes the signal representative of P1, and wherein said third means comprises a fuel gas heating value compensator system operating said inlet control valve to adjust P1 responsive to changes in G.
Claim 70
Dependent Claim
18 words
The fuel gas fired heating system of claim 12 wherein: C P1 (G+k) wherein k an adjustable constant.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-14 | 1979-01-13 | 1979-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-14 | 1983-01-13 | 1983-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-14 | 1987-01-13 | 1987-07-15 | $7700.00 | Window Closed / Lapsed |