In the era of commodity shortage, custody is often synonymous with long-term storage, storage and warehousing. People regard warehouses as "hotels" and those who open "hotels" hope that the longer the guests stay, the better. From this point of view, the function of warehousing is simply to store, store, manage and maintain. With the development of economy, especially with the rapid change of electronic information technology with computer as the core, in order to reduce circulation links and save logistics costs, people increasingly think that warehouses should not be "hotels", but should be regarded as "stations". People who manage "stations" hope that passengers will come and go in a hurry, and shorten the time spent in "stations". In this sense, people think that warehouses should not be "hotels", but should be regarded as "stations". The role of warehouse has changed fundamentally, from the main function of storage to the main function of circulation. Most warehouses in modern developed countries turn to logistics centers, distribution centers or circulation centers. From here, the manufacturer knows the speed and turnover rate of its products, from which it can get what products are best-selling and what products are unsalable, thus deciding what to produce and what not to produce. And take custody as the information source, make decision according to the collection and analysis of all kinds of data in the chain of custody, and decide the specific strategies and methods of production and sales promotion. That is to say, "custody" also has the function of information feedback.

  3. Packaging function
  Packing can be roughly divided into two categories. One is industrial packaging, or transport packaging, large packaging; the other is commercial packaging, or sales packaging, small packaging. The objects of industrial packaging are cement, coal, steel, ore, cotton, grain and other large-scale means of production. When transporting coal and ore by train, it is only necessary to cover the car skin with rayon and fix it with rope. Barley and wheat imported from abroad are poured into the warehouse only in bulk, without bagging. Cement transportation also emphasizes bulk loading in order to save costs and facilitate loading and unloading and transportation. But no packaging or simple packaging, there is a principle that can not be violated. This is to be waterproof, moisture-proof, moisture-proof, extrusion-proof, impact-proof, damage-proof, loss-proof, pollution-proof, and to ensure that no deterioration, deformation, corrosion, freshness, freshness, etc. are maintained during transportation. In addition, there are also several principles that should be followed in packaging. That is, after packaging, products should be easy to transport, loading and unloading, storage, quality and quantity, and sales. In developed countries, the rationality of packaging, the convenience and efficiency of handling, handling and transportation, as well as the ability of respecting porters (such as no more than 24 kilograms per unit of packaging, such weight women can bear) are taken into account in product design stage.
  The main purpose of commercial packaging is to promote sales, packaging fine, sophisticated, in order to facilitate publicity and attract consumers to buy.
  From this point of view, the function and function of packaging can not be underestimated. Paying attention to packaging is one of the important links to ensure the smooth flow of the whole logistics system.
  Loading, unloading and handling functions
  Loading, unloading and handling is the interface of logistics operation links, and the fundamental guarantee for the smooth realization of transportation, storage, packaging and other logistics operations. Loading and unloading are often accompanied by handling. The quality and efficiency of handling and handling are the key to the whole logistics process.
  We know that the movement of products or semi-finished products on the production line itself is a process of handling, loading and unloading. After packaging, there are loading and unloading trucks, warehousing and other handling operations. We do not know how many times to load and unload in the whole transportation, storage and packaging of goods. If the handling tools, facilities and equipment are not advanced and the handling efficiency is low, the circulation time of goods will be prolonged and the goods will be damaged, which will naturally increase the logistics cost and affect the quality of the whole logistics process.
  Although loading, unloading and handling do not create value by themselves, they will affect the use value of goods, and this link can not be omitted, this process can not be omitted. Because of the current level of loading and unloading operation in our country, there is still a big gap between mechanization and automation degree and developed countries. The phenomenon of packaging damage and loss caused by barbaric loading and unloading occurs from time to time. The rate of cargo damage has been very high, and this part of the cost remains high. It is necessary to attach importance to handling and handling. At the same time, we need to know that the function of loading and unloading and handling is the connection point of transportation, storage and packaging subsystems. The quality of the connection point is directly related to the quality and efficiency of the entire logistics system, and it is also an important part of shortening the moving time of goods and saving logistics costs. If there is a problem in the loading and unloading process, the other logistics links will stop.
  Circulation Processing Function
  When it comes to the function of circulation processing, we might as well give some examples first.
  For example, when fishing in deep sea, the ship can return at least one month after going out to sea. In order to prevent the decay of seafood and reduce the occupancy space, fishermen carry out sorting and digging on the ship, which is called the circulation processing of fish. Moreover, the process of cutting, nesting, bending and pressing steel coils in the circulation center is also called circulation processing, which is called steel circulation processing. In addition, cement mixing station mixes sand, stone, cement and additives, and then transports them to the construction site for pouring. It is also circulation processing, called cement circulation processing. In addition, it is circulation processing to transporting the cut logs to the timber factory for processing into plates, slabs or composite materials, which is also called wood circulation processing.
  From this point of view, the so-called circulation processing is a kind of value-added activity between production and consumption. It belongs to the primary processing of a product, a form of socialized division of labor and specialized production, and a mode of logistics that makes physical changes (such as changes in size, shape, quantity, etc.) of goods. Through circulation processing, materials can be saved, finished product rate can be improved, supply quality can be guaranteed and better service for users. Therefore, the role of circulation processing can not be underestimated. Circulation processing is the sublimation of "quality" in the process of logistics, which makes circulation develop to a deeper level. Foreign countries have attached great importance to it since the 1960s.