GB 50151-1992 Design specification for low expansion foam fire extinguishing system
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Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
GB50151—92
Code of design for low expansion foam fire extinguishing system
1992-01-10
State Bureau of Technical Supervision
Ministry of Construction of the People's Republic of China
Engineering Construction Standard Full-text Information System
1992-07-01
Jointly Issued
Engineering Construction Standard Full-text Information System
National Standard of the People's Republic of China
Code of design for low expansion foam fire extinguishing system
GB50151—92
Editor Department: Ministry of Public Security of the People's Republic of China Approval Department: Chinese Ministry of Construction of the People's Republic of China Date of implementation: July 1, 1992
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Partial Revision Announcement
No. 25
National Standard "Design Specification for Low-expansion Foam Fire Extinguishing System" GB50151-92 has been partially revised by the Tianjin Fire Science Research Institute of the Ministry of Public Security in conjunction with relevant units. The relevant departments have reviewed and approved the partially revised provisions, which will be implemented from October 1, 2000, and the corresponding provisions in the original specification will be abolished at the same time. This is hereby announced.
Ministry of Construction of the People's Republic of China
August 25, 2000
Engineering Construction Standards Full Text Information System
Engineering Construction Standards Full Text Information System
Notice on the Release of the National Standard "Design Specifications for Low-Expansion Foam Fire Extinguishing Systems"
Construction Standards [1992] No. 30
According to the requirements of the State Planning Commission's Document No. [1986] 2630, the "Design Specifications for Low-Expansion Foam Fire Extinguishing Systems" jointly compiled by the Ministry of Public Security and relevant departments has been reviewed by relevant departments. The "Design Specifications for Low-Expansion Foam Fire Extinguishing Systems" GB50151-92 is now approved as a national standard and will be implemented from July 1, 1992. This specification is managed by the Ministry of Public Security, interpreted by the Tianjin Fire Science Research Institute of the Ministry of Public Security, and organized for publication and distribution by the Standard and Quota Research Institute of the Ministry of Construction. Ministry of Construction of the People's Republic of China
January 10, 1992
Engineering Construction Standards Full-text Information System
Engineering Construction Standards Full-text Information System
Compilation Instructions
This specification is compiled in accordance with the notification of the State Planning Commission's [1986] No. 2630 document, and is jointly compiled by the Tianjin Fire Science Research Institute of the Ministry of Public Security, the Beijing Design Institute of China Petrochemical Corporation, Luoyang Petrochemical Engineering Company, Daqing Petroleum Exploration and Design Institute of China National Petroleum Corporation, and the Tianjin Municipal Public Security Bureau Fire Brigade. During the preparation process, the comrades of the specification preparation group followed the relevant national guidelines and policies and the fire protection work principle of "prevention first, prevention and control combined", conducted extensive investigations and studies on the scientific research, design and use status of low-multiple foam fire extinguishing systems in my country, combined with the domestic large-scale and Sino-Japanese oil fire extinguishing tests, verified the supply strength of the foam mixture, and specifically verified the applicability of the ring pump type proportional mixing process under self-priming conditions. On the basis of absorbing existing scientific research results and practical experience in engineering design, reference was made to the design, installation, acceptance specifications and materials of low-multiple foam fire extinguishing systems in the United States, Japan, Germany, the Soviet Union and the International Organization for Standardization (ISO), and solicited opinions from scientific research, design, colleges and universities, large petrochemical enterprises and public security fire supervision agencies in some provinces, cities and relevant ministries and commissions. Finally, it was jointly reviewed and finalized by relevant departments.
This specification is divided into four chapters and two appendices. Its main contents are: general principles, selection of foam liquid and system type, system design, system components, etc. In view of the fact that this specification is compiled for the first time, we hope that all units will pay attention to accumulating information and summarizing experience during the implementation process. If you find that there is a need for modification and supplementation, please send your opinions and relevant information to the Tianjin Fire Science Research Institute of the Ministry of Public Security (Address: Liqizhuang, Tianjin, Postal Code: 300381) for reference in future modifications. Ministry of Public Security of the People's Republic of China
October 1991
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 1 General
Chapter 2 Selection of Foam Liquid and System Type Section 1 Selection, storage and preparation of foam liquid Section 2
Selection of system type
Chapter 3 System design
Section 1
Section 2
Section 3
General provisions
Design of the above-liquid spray foam fire-extinguishing system in the tank area Design of the underwater spray foam fire-extinguishing system in the tank area Section 4
Foam spray system
Section 5
Foam pump station
Section 6
Foam monitor and foam gun system
Hydraulic calculation
Section 7
Chapter 4 System components
Section 1
Section 2
General provisions||t t||Foam fire pump and foam proportioning mixer
Foam liquid storage tank
Section 3
Foam generator
Section 4
Section 5
Valves and pipes
Appendix Glossary
Explanation of terms used in this specification
Appendix II
Additional explanation
Engineering construction standard full text information system
Engineering construction standard full text information system
Chapter 1 General
Article 1.0.1
This specification is formulated in order to reasonably design low-multiple air foam fire extinguishing system (hereinafter referred to as foam fire extinguishing system), reduce fire losses, and ensure personal and property safety.
Article 1.0.2 The design of foam fire extinguishing system must comply with relevant national guidelines and policies, and be safe and reliable, technologically advanced, economically reasonable, and easy to manage. This specification applies to the design of foam fire extinguishing systems installed in places where Class A (except for liquid hydrocarbons), B and C liquids are processed, stored, loaded and unloaded. This specification does not apply to the design of foam fire extinguishing systems installed in places such as ships and offshore oil platforms.
Article 1.0.4
In addition to implementing the provisions of this specification, the design of foam fire extinguishing systems shall also comply with the requirements of relevant national standards and specifications in force. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 2 Selection of Foam Liquid and System Type Section 1 Selection, Storage and Preparation of Foam Liquid Article 2.1.1
For non-water-soluble Class A, B and C liquid storage tanks, when using liquid-spraying foam for fire extinguishing, protein, fluoroprotein, water-forming film or film-forming fluoroprotein foam liquid can be selected; when using liquid-spraying foam for fire extinguishing, fluoroprotein, water-forming film or film-forming fluoroprotein foam liquid should be selected.
Article 2.1.1A
For foam spray systems, foam gun systems, and foam monitor systems that protect non-water-soluble Class A, B, and C liquids, when using air-breathing foam generating devices such as foam nozzles, foam guns, and foam monitors, protein, fluoroprotein, water-forming film, or film-forming fluoroprotein foam liquids may be selected; when using non-air-breathing spraying devices such as water nozzles, water guns, and water monitors, water-forming film or film-forming fluoroprotein foam liquids should be selected. For water-soluble Class A, B, and C liquids and unleaded gasoline with an oxygen-containing additive content exceeding 10% by volume, as well as for using a set of foam fire extinguishing systems to simultaneously protect water-soluble and non-water-soluble Class A, B, and C liquids, anti-soluble foam liquids must be selected.
Article 2.1.3 The storage temperature of the foam liquid should be 0-40°C, and it should be stored in a ventilated and dry room or shed.
The water source used to prepare the foam mixture shall meet the following requirements. Article 2.1.4
The water source used to prepare the foam mixture shall be equipped according to the appropriate water quality requirements for the foam liquid:
3. The water temperature for preparing the foam mixture should be 4℃～35℃; Section 2 System Type Selection
Article 2.2.1
When selecting a fixed, semi-fixed or mobile foam fire extinguishing system, the relevant specifications shall be met. Article 2.2.2. The selection of foam fire extinguishing system in tank area shall meet the following requirements:
1. For fixed-roof storage tanks of non-water-soluble Class A, B, and C liquids, the liquid-on-spray foam fire extinguishing system, the liquid-on-spray foam fire extinguishing system or the semi-liquid-on-spray foam fire extinguishing system may be selected.
2. For fixed-roof storage tanks of water-soluble Class A, B, and C liquids, the liquid-on-spray foam fire extinguishing system or the semi-liquid-on-spray foam fire extinguishing system shall be selected. 3. For external floating roof and internal floating roof storage tanks of Class A, B, and C liquids, the liquid-on-spray foam fire extinguishing system shall be selected.
4. For external floating roof storage tanks of non-water-soluble liquids, internal floating roof storage tanks, fixed roof storage tanks with a diameter greater than 18m, and vertical storage tanks of water-soluble liquids, foam cannons shall not be selected as the main fire extinguishing facilities.
5. For fixed-roof storage tanks with a height greater than 7m and a diameter greater than 9m, foam guns shall not be selected as the main fire extinguishing facilities.
Article 2.2.3 The following places should use foam spray system: 1. Indoor places where non-water-soluble Class A, B and C liquids may leak; 2. Indoor places where water-soluble Class A, B and C liquids with a leakage thickness not exceeding 25mm may leak;
3. Indoor places where water-soluble Class A, B and C liquids with a leakage thickness exceeding 25mm but with buffers may leak.
Article 2.2.4 The loading and unloading platform of Class A, B and C liquids on tank trucks or train tank trucks can use foam spray system or foam cannon system. Article 2.2.5 The outdoor flow fire area of Class A, B and C liquids with cofferdams should use foam spray system, foam cannon or foam gun system according to the specific conditions of the protected area.
Article 2.2.6 The outdoor flow fire area of Class A, B and C liquids without cofferdams should use mobile foam cannon or foam gun system. 3
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Engineering Construction Standard Full Text Information System
Chapter III System Design
Section I General Provisions
The design amount of foam mixture to be used for extinguishing a fire in a storage tank area by a foam fire extinguishing system shall be calculated according to Formula 3.1.1-1 and shall be determined based on the tank with the largest sum of the amount in the tank, the amount of the auxiliary foam gun of the tank, and the remaining amount in the pipeline: M=A·R·T+nQ·t+V|| tt||(3.1.1-1)
M is the designed amount of foam mixture for extinguishing a fire (L); where:
A is the protection area of a single storage tank (m); the supply intensity of foam mixture (L/minm2); R
T is the continuous supply time of foam mixture (min); n is the number of auxiliary foam guns in the calculated storage tank; Q is the foam mixture flow rate of each auxiliary foam gun (L/min); t is the continuous supply time of the mixture of the foam gun (min); V is the remaining amount of foam mixture in the system pipeline (L). 2. The design amount of foam mixture for extinguishing a fire by a foam sprinkler system should be calculated according to Formula 3.1.1-2:
M=A·R·T
(3.1.1-2)
Wherein: M is the design amount of foam mixture for extinguishing a fire by a foam sprinkler system (L);
A is the maximum protection area of the foam sprinkler system (㎡); Rz is the supply intensity of the foam mixture of the foam sprinkler system (L/minm2); Tz is the continuous supply time of the foam mixture of the foam sprinkler system (min). 4
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
3. The design amount of foam mixture for foam cannon and foam gun system to extinguish a fire should be calculated according to Formula 3.1.1-3:
(3.1.1-3)
M——Foam mixture for foam cannon and foam gun system to extinguish a fire in the formula:
Design amount of foam mixture (L);
A——The maximum protection area of foam cannon and foam gun system to extinguish a fire (m);
-Foam mixture supply intensity of foam cannon and foam gun system (L/min·m2);
T3——Continuous supply time of foam mixture of foam cannon and foam gun system (min).
Article 3.1.2
The protection area of the tank shall be determined in accordance with the following provisions: For fixed roof tanks, shallow pan type and floating pan type internal floating roof tanks made of fusible materials, it shall be the cross-sectional area of the tank; For external floating roof tanks, single and double pan type internal floating roof tanks, it shall be the annular area between the tank wall and the foam weir plate.
Article 3.1.3 When a fixed foam fire extinguishing system is used, in addition to the fixed foam fire extinguishing equipment, mobile foam fire extinguishing equipment such as foam hook pipes, foam guns and foam fire trucks shall also be set up.
Article 3.1.4
In the tank area where a fixed foam fire extinguishing system is set up, auxiliary foam guns for extinguishing liquid dispersion fires shall be set up outside its firebreak. The number and continuous supply time of foam mixture shall not be less than the provisions of Table 3.1.4. The foam mixture flow rate of each auxiliary foam gun shall not be less than 240L/min. 5
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Engineering Construction Standard Full-text Information System
Number of foam guns and continuous supply time
Tank diameter (m)
>10 and ≤20
>20 and ≤30
>30 and ≤40
Article 3.1.5
Number of foam guns equipped
Continuous supply time (min)
When the foam mixture flow rate of the fixed foam fire extinguishing system in the tank area is greater than or equal to 100L/s, the system's pumps, proportional mixing devices and control valves and main pipe control valves on their pipelines should have remote control functions. When the selected equipment is set up in an environment with explosion and fire hazards, it should comply with the provisions of the "Design Code for Electrical Installations in Explosive and Fire Hazardous Environments".
Article 3.1.6
A location for installing a foam mixture flow detection instrument should be reserved on the main foam mixture pipeline of the fixed foam fire extinguishing system, and a test detection port should be set on the foam mixture pipeline.
Article 3.1.7
When the fixed foam fire extinguishing system in the tank area shares a fire water supply pump with the fire cooling water system, measures should be taken to ensure that the supply intensity of the foam mixture meets the design requirements, and it shall not be ensured by temporary adjustments during fire. Article 3.1.8
In the tank area using a fixed foam fire extinguishing system, foam fire hydrants should be evenly arranged along the outside of the fire dike. The spacing between foam fire hydrants should not be greater than 60m, and the number of installations should not be less than 4.
Article 3.1.9
Function.
Fixed foam fire extinguishing system in tank area should have semi-fixed system Section 2
Article 3.2.1
Design of liquid spray foam fire extinguishing system in tank area The foam mixture supply intensity and continuous supply time of fixed and semi-fixed liquid spray foam fire extinguishing system of fixed roof tanks shall comply with the following provisions:
Engineering Construction Standard Full Text Information System1-1 calculation, and should be determined by the tank with the largest sum of the amount in the tank, the amount of the auxiliary foam gun of the tank, and the remaining amount in the pipeline: M=A·R·T+nQ·t+V
(3.1.1-1)
M is the designed amount of foam mixture for extinguishing a fire (L); where:
A is the protection area of a single tank (m); the supply intensity of the foam mixture (L/minm2); R
T is the continuous supply time of the foam mixture (min); n is the number of auxiliary foam guns in the calculated tank; Q is the foam mixture flow rate of each auxiliary foam gun (L/min); t is the continuous supply time of the mixture of the foam gun (min); V is the remaining amount of foam mixture in the system pipeline (L). 2. The design amount of foam mixture for extinguishing a fire by a foam sprinkler system should be calculated according to Formula 3.1.1-2:
M=A·R·T
(3.1.1-2)
Wherein: M is the design amount of foam mixture for extinguishing a fire by a foam sprinkler system (L);
A is the maximum protection area of the foam sprinkler system (㎡); Rz is the supply intensity of the foam mixture of the foam sprinkler system (L/minm2); Tz is the continuous supply time of the foam mixture of the foam sprinkler system (min). 4
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
3. The design amount of foam mixture for foam cannon and foam gun system to extinguish a fire should be calculated according to Formula 3.1.1-3:
(3.1.1-3)
M——Foam mixture for foam cannon and foam gun system to extinguish a fire in the formula:
Design amount of foam mixture (L);
A——The maximum protection area of foam cannon and foam gun system to extinguish a fire (m);
-Foam mixture supply intensity of foam cannon and foam gun system (L/min·m2);
T3——Continuous supply time of foam mixture of foam cannon and foam gun system (min).
Article 3.1.2
The protection area of the tank shall be determined in accordance with the following provisions: For fixed roof tanks, shallow pan type and floating pan type internal floating roof tanks made of fusible materials, it shall be the cross-sectional area of the tank; For external floating roof tanks, single and double pan type internal floating roof tanks, it shall be the annular area between the tank wall and the foam weir plate.
Article 3.1.3 When a fixed foam fire extinguishing system is used, in addition to the fixed foam fire extinguishing equipment, mobile foam fire extinguishing equipment such as foam hook pipes, foam guns and foam fire trucks shall also be set up.
Article 3.1.4
In the tank area where a fixed foam fire extinguishing system is set up, auxiliary foam guns for extinguishing liquid dispersion fires shall be set up outside its firebreak. The number and continuous supply time of foam mixture shall not be less than the provisions of Table 3.1.4. The foam mixture flow rate of each auxiliary foam gun shall not be less than 240L/min. 5
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
Number of foam guns and continuous supply time
Tank diameter (m)
>10 and ≤20
>20 and ≤30
>30 and ≤40
Article 3.1.5
Number of foam guns equipped
Continuous supply time (min)
When the foam mixture flow rate of the fixed foam fire extinguishing system in the tank area is greater than or equal to 100L/s, the system's pumps, proportional mixing devices and control valves and main pipe control valves on their pipelines should have remote control functions. When the selected equipment is set up in an environment with explosion and fire hazards, it should comply with the provisions of the "Design Code for Electrical Installations in Explosive and Fire Hazardous Environments".
Article 3.1.6
A location for installing a foam mixture flow detection instrument should be reserved on the main foam mixture pipeline of the fixed foam fire extinguishing system, and a test detection port should be set on the foam mixture pipeline.
Article 3.1.7
When the fixed foam fire extinguishing system in the tank area shares a fire water supply pump with the fire cooling water system, measures should be taken to ensure that the supply intensity of the foam mixture meets the design requirements, and it shall not be ensured by temporary adjustments during fire. Article 3.1.8
In the tank area using a fixed foam fire extinguishing system, foam fire hydrants should be evenly arranged along the outside of the fire dike. The spacing between foam fire hydrants should not be greater than 60m, and the number of installations should not be less than 4.
Article 3.1.9
Function.
Fixed foam fire extinguishing system in tank area should have semi-fixed system Section 2
Article 3.2.1
Design of liquid spray foam fire extinguishing system in tank area The foam mixture supply intensity and continuous supply time of fixed and semi-fixed liquid spray foam fire extinguishing system of fixed roof tanks shall comply with the following provisions:
Engineering Construction Standard Full Text Information System1-1 calculation, and should be determined by the tank with the largest sum of the amount in the tank, the amount of the auxiliary foam gun of the tank, and the remaining amount in the pipeline: M=A·R·T+nQ·t+V
(3.1.1-1)
M is the designed amount of foam mixture for extinguishing a fire (L); where:
A is the protection area of a single tank (m); the supply intensity of the foam mixture (L/minm2); R
T is the continuous supply time of the foam mixture (min); n is the number of auxiliary foam guns in the calculated tank; Q is the foam mixture flow rate of each auxiliary foam gun (L/min); t is the continuous supply time of the mixture of the foam gun (min); V is the remaining amount of foam mixture in the system pipeline (L). 2. The design amount of foam mixture for extinguishing a fire by a foam sprinkler system should be calculated according to Formula 3.1.1-2:
M=A·R·T
(3.1.1-2)
Wherein: M is the design amount of foam mixture for extinguishing a fire by a foam sprinkler system (L);
A is the maximum protection area of the foam sprinkler system (㎡); Rz is the supply intensity of the foam mixture of the foam sprinkler system (L/minm2); Tz is the continuous supply time of the foam mixture of the foam sprinkler system (min). 4
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
3. The design amount of foam mixture for foam cannon and foam gun system to extinguish a fire should be calculated according to Formula 3.1.1-3:
(3.1.1-3)
M——Foam mixture for foam cannon and foam gun system to extinguish a fire in the formula:
Design amount of foam mixture (L);
A——The maximum protection area of foam cannon and foam gun system to extinguish a fire (m);
-Foam mixture supply intensity of foam cannon and foam gun system (L/min·m2);
T3——Continuous supply time of foam mixture of foam cannon and foam gun system (min).
Article 3.1.2
The protection area of the tank shall be determined in accordance with the following provisions: For fixed roof tanks, shallow pan type and floating pan type internal floating roof tanks made of fusible materials, it shall be the cross-sectional area of the tank; For external floating roof tanks, single and double pan type internal floating roof tanks, it shall be the annular area between the tank wall and the foam weir plate.
Article 3.1.3 When a fixed foam fire extinguishing system is used, in addition to the fixed foam fire extinguishing equipment, mobile foam fire extinguishing equipment such as foam hook pipes, foam guns and foam fire trucks shall also be set up.
Article 3.1.4
In the tank area where a fixed foam fire extinguishing system is set up, auxiliary foam guns for extinguishing liquid dispersion fires shall be set up outside its firebreak. The number and continuous supply time of foam mixture shall not be less than the provisions of Table 3.1.4. The foam mixture flow rate of each auxiliary foam gun shall not be less than 240L/min. 5
Engineering Construction Standard Full-text Information System
Engineering Construction Standard Full-text Information System
Number of foam guns and continuous supply time
Tank diameter (m)
>10 and ≤20
>20 and ≤30
>30 and ≤40
Article 3.1.5
Number of foam guns equipped
Continuous supply time (min)
When the foam mixture flow rate of the fixed foam fire extinguishing system in the tank area is greater than or equal to 100L/s, the system's pumps, proportional mixing devices and control valves and main pipe control valves on their pipelines should have remote control functions. When the selected equipment is set up in an environment with explosion and fire hazards, it should comply with the provisions of the "Design Code for Electrical Installations in Explosive and Fire Hazardous Environments".
Article 3.1.6
A location for installing a foam mixture flow detection instrument should be reserved on the main foam mixture pipeline of the fixed foam fire extinguishing system, and a test detection port should be set on the foam mixture pipeline.
Article 3.1.7
When the fixed foam fire extinguishing system in the tank area shares a fire water supply pump with the fire cooling water system, measures should be taken to ensure that the supply intensity of the foam mixture meets the design requirements, and it shall not be ensured by temporary adjustments during fire. Article 3.1.8
In the tank area using a fixed foam fire extinguishing system, foam fire hydrants should be evenly arranged along the outside of the fire dike. The spacing between foam fire hydrants should not be greater than 60m, and the number of installations should not be less than 4.
Article 3.1.9
Function.
Fixed foam fire extinguishing system in tank area should have semi-fixed system Section 2
Article 3.2.1
Design of liquid spray foam fire extinguishing system in tank area The foam mixture supply intensity and continuous supply time of fixed and semi-fixed liquid spray foam fire extinguishing system of fixed roof tanks shall comply with the following provisions:
Engineering Construction Standard Full Text Information SystemArticle 7
When the fixed foam fire extinguishing system in the tank area shares a set of fire water supply pumps with the fire cooling water system, measures should be taken to ensure that the supply intensity of the foam mixture meets the design requirements, and it shall not be ensured by temporary adjustments during fire. Article 3.1.8
In the tank area using a fixed foam fire extinguishing system, foam fire hydrants should be evenly arranged along the outside of the fire dike. The spacing between foam fire hydrants should not be greater than 60m, and the number of installations should not be less than 4.
Article 3.1.9
Function.
The fixed foam fire extinguishing system in the tank area should have a semi-fixed system Section 2
Article 3.2.1
Design of the liquid spray foam fire extinguishing system in the tank area The foam mixture supply intensity and continuous supply time of the fixed and semi-fixed liquid spray foam fire extinguishing systems of fixed-top tanks shall comply with the following provisions:
Engineering Construction Standard Full Text Information SystemArticle 7
When the fixed foam fire extinguishing system in the tank area shares a set of fire water supply pumps with the fire cooling water system, measures should be taken to ensure that the supply intensity of the foam mixture meets the design requirements, and it shall not be ensured by temporary adjustments during fire. Article 3.1.8
In the tank area using a fixed foam fire extinguishing system, foam fire hydrants should be evenly arranged along the outside of the fire dike. The spacing between foam fire hydrants should not be greater than 60m, and the number of installations should not be less than 4.
Article 3.1.9
Function. bzxZ.net
The fixed foam fire extinguishing system in the tank area should have a semi-fixed system Section 2
Article 3.2.1
Design of the liquid spray foam fire extinguishing system in the tank area The foam mixture supply intensity and continuous supply time of the fixed and semi-fixed liquid spray foam fire extinguishing systems of fixed-top tanks shall comply with the following provisions:
Engineering Construction Standard Full Text Information System
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