Logistics warehousing solutions

一、Overview of logistics and warehousing industry

As one of the essential elements in the logistics industry, logistics warehouse plays an important role in the whole circulation operation. Its function has developed from simple storage and safekeeping of materials to multiple functions such as material receiving, classification, measurement, packaging, sorting, distribution and storage point. In the design of logistics warehouse, the principle of flow is followed, so that the stored products can flow directly in the whole warehouse facilities, and the allocation and arrangement are carried out continuously, and the small inventory and high profit can be realized through the optimal allocation of resources. Its main layout features are: maximizing storage in the three-dimensional space of the logistics warehouse; minimizing cargo handling operations in the reservoir area; and realizing functional service diversification in the specific area of the reservoir area. This determines the characteristics of large space, high storage, high density and easy flow of logistics warehouse. Logistics warehouse can be divided into distribution center type warehouse, storage center type warehouse and logistics center type warehouse according to the purpose of use; according to the structure of buildings, it can be divided into bungalow type warehouse, building type warehouse and high-rise shelf warehouse (referred to as elevated warehouse) and other forms. No matter what type of warehouse, it puts forward high requirements for fire safety.

二、Fire characteristics of logistics storage

The main building functions of the logistics warehouse, such as cargo transfer, split storage, loading and unloading distribution, determine the large capacity and easy turnover of the logistics warehouse. Its fire risk has its own characteristics.

2.1 in order to reduce the cost of logistics and improve the utilization rate of space, the design of logistics warehouse in recent years has developed into a large-scale and large-scale direction, from 3000-6000m2 of single floor to more than 10000m2, or even some three-dimensional logistics centers, with a building area of hundreds of thousands of square meters. In order to improve the utilization rate of the warehouse, the stored goods often have diversity, such as paper plastic products, rubber products, textiles, daily necessities, chemicals, cigarettes, tapes, and even storage of chemical inflammables. Even for mechanical and electrical parts, there are many combustible materials in their outer packaging. Due to the large space of the logistics warehouse, the oxygen supply is sufficient after the fire, especially the elevated warehouse, there is a certain gap between the shelves, so that the fire can quickly spread in the warehouse.

2.2 the logistics warehouse with large fire damage and economic loss is generally of steel structure, especially the elevated warehouse. The shelves set inside are generally of steel structure. The strength of steel varies greatly with the increase of temperature. When the temperature reaches 600 ℃, the strength of steel will decrease by 75% - 80%, and the supporting capacity has been completely lost. When the general solid is burning, the flame temperature can reach 700 ℃ in about 10 minutes. If the fire is not controlled in time at the initial stage, it will often cause the collapse of the steel structure, resulting in greater economic losses. The high-density goods are stored in the automated warehouse, with expensive automatic handling, storage equipment and peripheral buildings. Once there is a fire, a large number of materials will be burned in a short time, resulting in huge economic losses.

2.3 it is difficult to smoke and put out the fire. At present, the logistics warehouse generally does not require mechanical smoke exhaust facilities. It is difficult for high-temperature smoke to pass through windows, doors and other parts of the natural emission. When the smoke layer reaches the top of the building, it gradually thickens and drops, forming a dark and toxic space environment in a short time, which makes it difficult for the safe evacuation of people in the fire and the fire fighting. Especially for the elevated warehouse, the building height is large, and the fire hydrant with general pressure has no ability to send the water gun to the top of the building. The space is large, and it is difficult to set fire separation. Such a large warehouse is very easy to cause a large area of fire, so it is difficult to put out the fire. On the other hand, the elevated warehouse is transported and lifted by stacker on the ground rail without personnel entering and leaving the shelf. The roadway is designed to a very small extent. Once a fire occurs, it is very difficult to enter the internal fire-fighting. Some elevated warehouses are designed without windows. The air conditioning system helps the fire spread, the lighting cannot be guaranteed, and the fire is not easy to be found. It is very inconvenient for firefighters to put out the fire by manpower.

三、Logistics warehousing solutions:

Inspiratory smoke fire detection alarm (hereinafter referred to as alarm) is a smoke sampling detection device based on professional laser optical air monitoring technology and microprocessor control technology. The equipment uses mature and professional laser optical technology and a variety of sensor processing technology, and integrates professional digital micro processing technology, which has many characteristics that other smoke detection technologies do not have. These characteristics improve the equipment performance, simplify the operation, and increase the reliability and stability of the system.

It is designed for the detection and alarm in the early stage of fire (overheating, smoldering, or low thermal radiation and aerosol generation stage). The alarm time is several hours ahead of the traditional fire detection, so as to reduce the fire loss as much as possible. It can not only be used as an independent detection system, but also connected to the control system provided by different fire equipment manufacturers. The design optimizes its performance while ensuring the installation and debugging as simple as possible.