CN202909351U - Layout structure for large-scale high expansion foam extinguishing system - Google Patents

Abstract

The utility model relates to an arrangement structure of a large-scale high-expansion foam fire extinguishing system, which is characterized in that the protected area under its jurisdiction is divided into several partitions, and each partition adopts a centrally controlled fire pump station and a fire control center; each partition is respectively set with a pressure ratio Tank-type foam fire extinguishing device, the foam stock solution is stored in the storage tank; high-expansion foam generators are installed in each protection area; the distance between the fire pump station and each protection area meets the delay time from the alarm to the foam generator starting to spray foam No more than 30s. Compared with the prior art, the beneficial effects of the utility model are: 1) The distance from the proportional mixer to the protection zone is shortened, and the time from the start of the fire extinguishing system to the foaming of the foam generator is shortened. 2) The pressure water and the foam liquid are separated by the diaphragm bag in the tank to prolong the life of the foam liquid. 3) The delay time from the alarm to the start of foam spraying is not more than 30s, which meets the requirements of international regulations.

Description

Arrangement structure of large high-expansion foam fire extinguishing system

technical field

The utility model relates to the technical field of foam fire extinguishing system design, in particular to an arrangement structure of a large-scale high-expansion foam fire extinguishing system.

Background technique

High-expansion foam fire extinguishing schemes are generally used in fire extinguishing systems in dangerous places such as underground lubrication stations, hydraulic stations, and underground oil depots in metallurgical enterprises. The American and German standards stipulate that the time from receiving a definite fire alarm signal to the foam generator starting to spray foam for the high-expansion foam fire extinguishing system is less than 30s, that is, the time from system startup to the foam generator starting to spray foam is less than 30s. Now my country has stipulated in "Code for Design of High Expansion and Medium Expansion Foam Fire Extinguishing System" GB50196-93 (2002 Edition) and "Code for Design of Foam Fire Extinguishing System" GB50151-2010 that "the high expansion foam fire extinguishing system starts to spray from the alarm to the foam" The delay time shall not exceed 1min".

Although the shorter the delay time from the alarm to the start of foam spraying, the more reliable the fire extinguishing system can be ensured to extinguish the fire as soon as possible, and the loss caused by the fire can be reduced. For fire extinguishing systems with different sizes and far distances from each other, it is necessary to meet the "delay time from alarm to foam spraying not exceeding 1min", or even not exceeding 30s, and to ensure that the system design is economical, reasonable, and existent. Considerable difficulty is a major problem in the design of high-expansion foam fire extinguishing systems.

In the past, designers often used two design methods: one is to mix water and foam liquid in advance, set control valves outside each protection area, and pre-fill the foam mixture to the front of the control valve in the protection area; One is to design a foam stock solution and a water pipeline to each protection area, and install a proportional mixer and a control valve outside each protection area. There are disadvantages in these two methods: the first method, due to the degradability of the foam liquid, after the foam liquid and water are mixed, it will degrade quickly and fail, and the foam liquid needs to be constantly replaced, causing a lot of waste. The second method is to use pipelines for long-term storage of foam stock solution, long-distance pipeline transportation of foam stock solution and a large number of proportional mixers. On the one hand, the foam stock solution is prone to failure when stored in pipelines. substantial improvement. From the perspective of technical safety and economical reliability, these two design schemes are unreasonable.

Contents of the invention

The purpose of this utility model is to provide a layout structure of a large-scale high-expansion foam fire extinguishing system, which overcomes the deficiencies of the prior art, and aims at the actual characteristics of scattered protection areas, unequal volumes, and long distances. The time from the alarm signal to the start of foam spraying by the foam generator is less than 30s, which prolongs the service life of the foam liquid and reduces engineering investment and maintenance of subsequent projects.

For solving the problems of the technologies described above, the technical solution of the utility model is:

The layout structure of the large-scale high-expansion foam fire extinguishing system is to divide the protected area under its jurisdiction into several partitions, and each partition adopts a centrally controlled fire pump station and fire control center; the fire pump station is equipped with a fire pump; each partition is equipped with a set of pressure Proportional tank-type foam fire extinguishing device; high-expansion foam generators are installed in each protection area; the setting position of the pressure ratio tank-type foam fire extinguishing device for the fire pump station and each partition meets the requirements from the system alarm to the foam generator in the corresponding protection area. The delay time of foaming shall not exceed 30s;

The fire pump station is connected to the pressure proportional tank foam fire extinguishing device of each partition respectively, and the pressure proportional tank foam fire extinguishing device of each partition is respectively connected to the high-expansion foam generator set in each protection area in the corresponding partition, and the fire pump outlet Electric control valves and pressure switches are respectively set on the pipes, the inlet pipes of the pressure proportional tank foam fire extinguishing device, the inlet pipes of the foam liquid, and the foam mixture pipes in each protection zone.

Compared with the prior art, the beneficial effects of the utility model are:

1) By dividing the entire protection area into several partitions according to reasonable distances, each partition adopts a set of pressure proportional tank foam fire extinguishing device, and the electric valve on the water inlet pipe of each pressure proportional tank foam fire extinguishing device is in pre-action State, a centrally controlled fire pump station is used between each partition, which shortens the distance from the proportional mixer to the protection area, and reduces the time from the start of the fire extinguishing system to the start of foaming by the foam generator.

2) The pressure water and the original foam liquid are separated by the diaphragm bag in the tank, and the foam liquid is sealed and stored, which is not easy to be corrupted and deteriorated, which greatly prolongs the service life of the foam liquid.

3) The delay time from the alarm to the start of foam spraying is not more than 30s, which not only meets the requirements of domestic regulations, but also meets the requirements of international regulations, which greatly reduces the project investment and maintenance of subsequent projects.

Description of drawings

Fig. 1 is a structural schematic diagram of an embodiment of the arrangement structure of the utility model.

Detailed ways

The specific embodiment of the utility model will be further described below in conjunction with accompanying drawing:

See Figure 1, which is a structural schematic diagram of an embodiment of the arrangement structure of the large-scale high-expansion foam fire extinguishing system of the present invention. The protected area under its jurisdiction is divided into several partitions, and each partition adopts a centralized control fire pump station and fire control center; Set up fire pumps; set up a set of pressure proportional tank foam fire extinguishing devices for each partition (the device includes a storage tank, a diaphragm bag and a pressure proportional mixer, and the foam stock solution is stored in the storage tank); set up high-expansion foam in each protection zone Generators, according to the size of the protection area and the process layout, two water conservancy-driven foam generators, PFS4 and PFS10, are selected respectively; the setting positions of the fire pump station and the pressure ratio tank foam fire extinguishing device of each partition meet the requirements from the system alarm to the corresponding protection. The delay time for the zone foam generator to start spraying foam shall not exceed 30s, which shall be determined by hydraulic calculation;

The storage tank volume of the pressure proportional tank foam fire extinguishing device used in each partition, the parameters of the pressure proportional mixer, the size of the inlet of water and foam stock solution and other parameters need to be based on the process layout of the largest protection zone in the partition, the foam liquid The continuous supply time, the layout of the foam generator and the pressure requirements are determined separately.

Each district adopts a centrally controlled fire pumping station. There are two fire pumps in the pump station. The head needs to be determined according to the pressure required by the foam generator at the most unfavorable point in the protection zone farthest from the fire pump station.

The fire pump station is connected to the pressure proportional tank foam fire extinguishing device of each partition respectively, and the pressure proportional tank foam fire extinguishing device of each partition is respectively connected to the high-expansion foam generator set in each protection area in the corresponding partition, and the fire pump outlet Electric control valves and pressure switches are respectively set on the pipes, the inlet pipes of the pressure proportional tank foam fire extinguishing device, the inlet pipes of the foam liquid, and the foam mixture pipes in each protection zone.

In the fire extinguishing method of the large-scale high-expansion foam fire extinguishing system of the present utility model, in the standby state, the electric control valve on the water inlet pipe of the pressure proportional tank type foam fire extinguishing device of each partition is in the pre-action state (that is, the normal pressure proportional tank type foam fire extinguishing The electric valve of the water inlet pipe of the device is filled with pressure water that meets the system requirements); in the fire extinguishing state, the action steps of each electric control valve are as follows:

1) After the fire control center receives the fire alarm signal (requires a second confirmation), the electric control valve on the foam mixture pipeline in the corresponding protection zone, the water inlet pipe and foam The raw liquid inlet electric control valve is opened immediately, and the fire pump is started at the same time;

2) The pressurized water enters the pressure proportional mixer and the diaphragm bag in the device respectively through the water inlet control valve of the pressure proportional tank foam fire extinguishing device. ;

3) After the pressure water and the original foam solution (heat-resistant and smoke-resistant foam fire extinguishing agent) are mixed into a 3-6% foam mixture by a pressure proportional mixer, the foam mixture is guided by the electric control valve on the foam mixture pipeline in the corresponding protection zone, and the foam mixture Arrive at the designated protection area through the electric butterfly valve at the entrance of the protection area, enter the water conservancy-driven high-expansion foam generator in the corresponding protection area, drive the foam generator to spray foam, and reach the minimum submerged height within the time specified in the specification, after which the foam continues Spray until the fire is finally extinguished.

Claims (1)

1. The layout structure of the large-scale high-expansion foam fire extinguishing system is characterized in that the protected area under its jurisdiction is divided into several partitions, and each partition adopts a centrally controlled fire pump station and fire control center; the fire pump station is equipped with a fire pump; each partition Set up a set of pressure proportional tank-type foam fire extinguishing devices; set up high-expansion foam generators in each protection zone; the setting positions of the fire pump station and the pressure-proportional tank-type foam fire extinguishing devices of each partition meet the requirements from the system alarm to the corresponding protection zone. The delay time for the foam generator to start spraying foam shall not exceed 30s; The fire pump station is connected to the pressure proportional tank foam fire extinguishing device of each partition respectively, and the pressure proportional tank foam fire extinguishing device of each partition is respectively connected to the high-expansion foam generator set in each protection area in the corresponding partition, and the fire pump outlet Electric control valves and pressure switches are respectively set on the pipes, the inlet pipes of the pressure proportional tank foam fire extinguishing device, the inlet pipes of the foam liquid, and the foam mixture pipes in each protection zone.

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