1. According to whether the shelf is fixed or mobile, it can be divided into:
(1) Fixed shelves: Fixed shelves can be subdivided into shelf-type, pallet-type, through-type, gravity-type, press-in type, attic type, steel platform type, cantilever type, mobile type, drawer type and bracket type.
(2) Mobile shelves: Mobile shelves can be subdivided into mobile shelves and rotating shelves, among which mobile shelves can be subdivided into light and medium-sized mobile shelves (also known as dense shelves, which are divided into manual and electric) and heavy pallet mobile shelves, and rotating shelves can be subdivided into horizontal rotating shelves and vertical rotating shelves.
2. According to whether the overall structure of the shelf is welded or assembled, it can be divided into:
(1) Weld the shelf. (2) Assembled shelves. At present, assembled shelves are widely used in China.
3. According to the relationship between the shelf system and the warehouse building structure, it can be divided into:
(1) integrated bracket. The shelf system and the roof of the building form an inseparable whole. The roof load is directly supported by the shelf columns, and the building envelope (wall) structure is installed on the columns on both sides.
(2) Independent structured shelves. Shelf system and architecture are two independent systems, and there is no direct connection between them.
4. According to the loading capacity of each layer of the shelf, it can be roughly divided into:
(1) Light-duty shelf: the load of each floor shall not exceed 200kg.
(2) Medium-sized shelves: each floor bears 200~500kg.
(3) Heavy-duty shelves: each floor bears more than 500kg.
5. According to the height of the shelf, it is divided into
(1) low frame: the height is less than 5m.
(2) High shelf: the height is 5~ 12m.
(3) Ultra-high shelf: 12m or more.
Three, the structural characteristics, scope of application and selection principles of various shelf systems.
1. shelf shelf. Shelf-type shelves are usually accessed manually, with assembled structure, uniform and adjustable floor spacing, and goods are often scattered or not very heavy packaged goods (convenient for manual access). Generally, the height of the shelf is below 2.5m, otherwise it is difficult for people to get close to it (for example, it can be set at about 3m with the help of a climbing car). The span (length) and depth (width) of unit shelves should not be too long. According to the load of each layer of the unit shelf, it can be divided into light, medium and heavy shelves, and the laminates mainly include steel laminates and wood laminates.
(1) Light-duty shelf: The bearing capacity of each floor of the unit shelf is not more than 200kg, and the total bearing capacity is generally not more than 2000kg. The span of a unit shelf is usually not more than 2m, the depth is not more than 1m (mostly less than 0.6m), and the height is generally less than 3m. The common shelf structure is angle steel column, which is light and beautiful in appearance and is mainly suitable for storing light and small items. Less capital investment, widely used in electronics, light industry, culture and education and other industries.
(2) Medium-sized shelves: the load of each layer of unit shelves is generally between 200 and 800 kg, and the total load is generally not more than 200-800kg. The span, depth and height of a unit frame are usually no more than 2.6m, 1m and 3m respectively. If the unit shelf span is less than 2m and the floor load is less than 500kg, it is usually more suitable to choose the flat beam middle shelf; If the unit shelf span is more than 2m, generally only the beam-type medium-sized shelf can be selected. Compared with beam-type medium-sized shelves, flat-type medium-sized shelves have larger adjustable space between floors, are more stable and beautiful, are more harmonious with the environment, and are more suitable for some warehouses with high cleanliness requirements. Beam-type medium-sized shelves are more industrialized and more suitable for storing metal structural products. Medium-sized shelves are widely used in all walks of life.
(3) Heavy-duty shelves: The load of each floor of a unit shelf is usually between 500~ 1500kg, the span of a unit shelf is generally within 3m, the depth is within 1.2m, and the height is not limited, so it usually coexists with heavy pallet shelves. The following floors are shelf-type, which can be operated manually. The part with a height of more than 2m is usually a pallet shelf, which is accessed by a forklift. It is mainly used in some occasions where full-time deposit and withdrawal are needed, and it is more common in large storage supermarkets and logistics centers.
2. Pallet shelf
Pallet-type shelves, also known as cross-beam shelves, or cargo shelves, are usually heavy-duty shelves, which are the most common in various storage shelf systems in China. First of all, containers should be unitized, that is, the characteristics and weight of goods packaging should be grouped to determine the type, specification and size of pallets, as well as the load capacity and stacking height of a single pallet (the weight of a single pallet is generally less than 2000kg), then the span, depth and floor spacing of unit shelves should be determined, and the shelf height should be determined according to the effective height of the lower edge of warehouse roof truss and the maximum fork height of forklift. Generally, the unit shelf span is within 4m, the depth is within 1.5m, the shelf height of high and low warehouses is generally within 12m, and the shelf height of Takakura is generally within 30m (these warehouses are basically automated warehouses, and the total shelf height is composed of several columns within 12m). In this kind of warehouses, advanced battery forklifts, balanced heavy-duty battery forklifts and three-fork forklifts are mostly used for storage and retrieval operations, and electric stackers can also be used when the shelves are short, and stackers are used for storage and retrieval operations in ultra-high warehouses. This kind of shelf system has high space utilization rate, flexible and convenient access, supplemented by computer management or control, and can basically meet the requirements of modern logistics system. Widely used in manufacturing, third-party logistics distribution center, etc. It is suitable for both multi-variety and small-batch projects and small-variety and large-batch projects. This kind of shelves are mostly used in high-rise warehouses and super-high-rise warehouses (shelves in automated warehouses are mostly used).
Step 3 go through the shelves
Through shelves are also called corridor shelves and drive-through shelves. This system has dense shelves and extremely high space utilization rate, which is almost twice that of pallet shelves, but the goods must be small in variety and large in quantity, and the goods must be first in and then out. First of all, it is necessary to carry out unitization work to determine the specifications, load capacity and stacking height of pallets. From this, the span, depth and floor spacing of unit shelves are determined, and the shelf height is determined according to the effective height of the lower edge of roof truss. It is best to control the total shelf depth in the wall area within 6 pallets, and the total shelf depth in the middle area that can enter and exit from both sides within 12 pallets, so as to improve the efficiency and reliability of forklift access (in this shelf system, the forklift is in a continuous "holding high and hitting high" operation mode, and it is easy for the forklift to shake and hit the shelf, so it is very important to fully consider the stability). The stability of this storage system is weak, and the shelf should not be too high. Generally, it should be controlled within 10m. In order to strengthen the stability of the whole shelf system, in addition to specifications and selection, fastening devices must be added. Single-supported goods should not be too big or too heavy, usually the weight should be controlled within 1500kg, and the pallet span should not be greater than1.5m. Forklifts are usually forward battery forklifts or balanced battery forklifts. Mostly used in dairy products, beverages and other food industries, but also in cold storage.
4. Gravity shelf
Gravity shelf evolved from pallet shelf, which adopts roller track or bottom wheel pallet, and the track has a certain slope (about 3). Using the self-weight of the goods, the goods are first in and first out, and they are discharged while entering. It is suitable for FIFO storage of large quantities of similar goods with high space utilization rate, especially for goods with certain shelf life and not suitable for long-term backlog. The total depth of the shelf (that is, the length of the guide rail) should not be too large, otherwise the upper and lower "dead corners" that cannot be used will be very large, which will affect the utilization of space. Moreover, the ramp is too long, the controllability of the slideway is poor, and the impact of the slideway is large, which easily leads to the unsmooth slideway, the jamming of the board and the overturning of the pallet goods. In order to make the slide smooth, if the ramp is long, a shock absorber should be added in the middle. In order to prevent pallet goods from tipping over due to excessive impact force when sliding to the bottom, it is necessary to install a buffer device and a pick-up and separation device at the lowest part of the ramp, which is difficult to design, manufacture and install and has high cost. Such shelves should not be too high, generally within 6m, and the weight of single-supported goods is generally within 1000kg, otherwise its reliability and operability will be reduced. This kind of shelf system has not been widely used in China at present.
5. Press-in shelves
Press-in shelves are also evolved from pallet shelves. Using the principle of combining the track with the pallet car, the track is inclined at a certain angle (about 3). Using the self-weight of the goods, the pallet goods come in first and then out, and go in and out on the same side. It is suitable for the storage of goods with few varieties and large quantities, with high space utilization rate and flexible access. The total depth of the shelf should not be too deep, generally within the depth of five pallets, otherwise the space will be greatly sacrificed because of the mutual embedding of pallet trucks. Generally, the weight of a single consignment is less than 1500kg, and the height of the shelf is generally less than 6 m. This system requires high manufacturing accuracy of the shelf, and the cooperation between the pallet trolley and the guide rail is particularly important. If the manufacturing and installation accuracy is not high, it will easily lead to poor operation of the shelf system. This kind of shelf has high cost and has been used in China.
6. Attic shelves
The attic shelf system is to build a middle attic on the existing workplace or shelf to increase the storage space. It can be used as a second-and third-floor attic, suitable for storing and taking some light bubbles and small and medium-sized items. Suitable for large or small batch access of various goods. Goods are usually transported to the second and third floors by forklifts, hydraulic lifting platforms or freight elevators, and then transported to a certain location by light vehicles or hydraulic pallet trucks. In this system, medium-sized shelves or heavy shelves are usually used as the support of the main body and the floor (which shelf is selected according to the total load of the unit shelf), and the floor is usually cold-rolled steel floor, patterned steel floor or steel grating floor. In recent years, the application of cold-rolled steel floor is increasing. It has the advantages of strong bearing capacity, good integrity, good stress uniformity, high precision, smooth surface and easy locking. There are many types to choose from, and it is easy to match the lighting system, and it is convenient to access and manage. The loading capacity of each layer of unit shelves is usually less than 500kg, the spacing between layers is usually 2.2m~2.7m, and the height of the top shelf is generally about 2m, which fully considers the convenience of man-machine operation. This system has many applications in auto parts, auto 4S shops, light industry, electronics and other industries.
7. Steel structure platform
Steel structure platform is usually a two-story or three-story fully assembled steel structure platform built on the existing workshop (warehouse) site, which changes the use space from one floor to two or three floors and makes full use of the space. The goods are transported to the second and third floors by forklift or elevator, and then transported to the designated place by handcart or hydraulic trailer. Compared with the reinforced concrete platform, the platform has the advantages of fast construction speed, moderate cost, convenient installation and disassembly, convenient use and novel and beautiful structure. The column spacing of this platform is generally within 4~6m, the height of the first floor is about 3m, and the height of the second and third floors is about 2.5m m. The columns are generally square pipes or round pipes, and the main and auxiliary beams are generally H-beams. The floor slab usually adopts cold-rolled steel floor, patterned steel floor and steel grating, and the floor load is usually within 1000kg per square meter. This platform can combine warehousing and management in the shortest distance, and both upstairs and downstairs can be used as warehouses. This kind of system is used in third-party logistics, machinery manufacturing and other industries.
8. cantilever shelf
Cantilever shelves are mainly used to store long materials, such as profiles, pipes, plates and cables. The columns are mostly made of H-beam or cold-rolled steel, the cantilever is made of square pipe, cold-rolled steel or H-beam, the cantilever is inserted or bolted with the column, the base is bolted with the column, and the base is made of cold-rolled steel or H-beam. Get close to the goods by forklift, crane or manually. The height of the shelf is usually within 2.5 meters (up to 6 meters if the goods are accessed by forklift), the cantilever length is within 1.5 meters, and the load of each arm is usually within 1000kg. This kind of shelves are mostly used in machinery manufacturing and building materials supermarkets.
9. Move the shelves
Mobile shelves are usually evolved from medium-sized cross-beam shelves, and roller-type aluminum alloy or sheet metal flow bars are arranged between the front and rear cross-beams of each layer of the shelves at a certain slope (about 3). Goods are usually packed in paper or put into plastic turnover boxes, and their own weight is used to realize the flow and first-in-first-out of goods. Goods are transported by handcart, which is convenient for manual access. The load capacity of each unit shelf is usually within 1000kg, and the shelf height is within 2.5 meters. It is suitable for flow conversion on both sides of the assembly line and picking operations in distribution centers and other places, and can be equipped with electronic tags to realize information management of goods.
10. Drawer rack
Drawer shelves evolved from heavy pallet shelves, which are usually used to store heavy objects such as molds, but there is no suitable forklift available on site. The assembled bolted shelf structure is generally below 2.5m in height, and several floors except the top floor can be designed as drawer-type structure, which is safe and reliable. Goods weighing 2000kg/ floor can be easily taken out, assisted by cranes or cranes, and the goods are convenient to access. This kind of shelf is mainly used to store molds and other special places.
1 1. bracket frame
Shelves are mainly used in automated warehouses. The pallet used in this shelf system has strong bearing capacity and good rigidity. For example, if the carrying capacity of the pallet is small, the cross beam is removed, or if the cargo hold is small and there is no cross beam, the plastic box is directly placed on the bracket, and the stacker automatically accesses the goods. Mainly used in tobacco, electronics, machinery manufacturing and other industries.
12. Moving shelves
Light and medium-sized mobile shelves (also known as dense shelves) evolved from light and medium-sized shelves, with dense structure, only one channel (about 1m wide), good sealing, beautiful and practical, safe and reliable, and it is a kind of shelf with the highest space utilization, including manual and electric. The guide rail can be embedded or installed on the ground, and the shelf base runs along the guide rail, and the shelf is installed on the base. Each row of shelves can move easily and smoothly through the sprocket transmission system, which can be divided into manual and electric, and the goods can be accessed manually. In order to prevent the shelving system from toppling over during operation, an anti-overturning device is usually provided. Mainly used in archives, libraries, banks, enterprise reference rooms, electronic light industry and other industries.
Heavy-duty mobile shelves are evolved from heavy-duty pallet-type shelves with exposed structure. Every two rows of shelves are placed on the base, which is equipped with walking wheels and runs along the track. The chassis is equipped with motor and reducer, alarm and sensing device. The system only needs 1~2 channels, and the space utilization rate is extremely high. The structure is similar to light and medium-sized mobile shelves, but the difference is that heavy mobile shelves must be electric, and the storage and access of goods are forklifts. Generally, the passage is about 3m, which is mainly used in places where the warehouse space is not very large and it is required to make maximum use of the space. It is suitable for machinery manufacturing and other industries.