Safe transportation of packages 1

Safe transportation of packages

transportation packaging aims at transporting and storing packages, which can protect the safety of products, facilitate storage, transportation, loading and unloading, and accelerate handover and inspection. As a necessary link in the circulation of packages, transportation is of great significance to the safe transfer of packages. In recent years, China's modern transportation industry has developed rapidly. Long distance transportation tools (such as cars, trains, ships and aircraft) and short-distance transportation tools (battery trailers, forklifts, forklifts, etc.) are complete, convenient and flexible, which promotes the development of modern packaging industry in the direction of packaging palletization, loading and unloading mechanization, transportation centralized loading and storage shelf. In this paper, the damage and safety of packaging in the process of transportation are analyzed and studied from the aspects of palletized packaging, container transportation, transportation protection and loading and unloading protection

1 reasons for package damage

there are three main reasons for package damage during transportation: impact, vibration and pressure. First of all, the start, speed change, steering and braking of vehicles, trains and other means of transport will change the speed of packages. The means of transport will produce periodic ups and downs and shaking due to factors such as road conditions, rail joints, engine vibration, vehicle shockproof performance, water surface wind and waves, air flow intensity and so on. If the stacking is loose and not fixed as a whole, the packages are easy to collide with the carriage or adjacent packages. Secondly, when the excitation frequency of the means of transport is equal to or very close to the intrinsic frequency of the product, the product will have resonance, which is easy to cause damage to the package. In addition, stacking can improve the space utilization of transportation tools, but the stability of packages varies significantly with different stacking methods, and the bottom package bears the greatest pressure. At the same time, the bottom package also bears the dynamic pressure of the carriage floor and the friction generated during horizontal displacement, and the dynamic pressure is more harmful to the package than the static pressure

it is precisely because various means of transportation or modes of transportation have different characteristics, so before transportation or transshipment, it is necessary to understand the combined transportation problems such as lifting vehicles, pallets, containers or container racks required by the package, so as to ensure the safe transportation of vulnerable components in the package

2 palletized packaging

pallets are widely used in combined packaging. Palletized packaging is to stack the packages on the pallet in a certain way, and then fix them by binding, wrapping or gluing to form a handling unit, which is convenient for mechanized loading and unloading, storage, transportation and management. The utility model is suitable for the rough stacking and unloading of pallets in the process of transportation, which can greatly improve the overall loading and unloading efficiency and the overall packing stability, and can greatly improve the overall loading and unloading efficiency

2.1 palletized packaging method

the quality of palletized packaging directly affects the safe transportation of packaging. Appropriate palletized packaging can improve the packaging effect, accelerate the circulation of goods and reduce the transportation and packaging cost. There are two methods of palletized packaging: (1) "from the inside to the outside" method is to design the inner packaging, outer packaging and tray according to the product size. (2) "From outside to inside" method is to optimize the design of outer packaging and inner packaging according to the size of standard tray

in the design of palletized packaging, the internationally recognized packaging modulus of rigid square should be followed × Mm2, 800 in the national standard gb2943-82 is preferred × 1200 and 1000 × 1200 size series tray

2.2 stacking mode

in the process of palletized packaging, the stacking mode of packages on the pallet is also a very important problem. The stacking methods of packages are generally divided into the following four forms: simple and important problems. The stacking methods of packages are generally divided into the following four forms: simple overlapping type, staggered type, vertical and horizontal type and rotary type. See Table 1 for their performance comparison

Table 1 Comparison of four stacking methods

Project weight, strength, processability and corrosion resistance price

aluminum container is light, small, good and poor, high

ordinary steel container is good and poor, low

stainless steel container is good and too high

FRP container is good and good, general

2.3 fastening methods

the fastening methods of packaging parts in the process of palletized packaging include binding, gluing Stretch packaging, shrink packaging, edge protection, etc

(1) bundling

the bundling and fastening method is usually gold, and metal or plastic bundling is also commonly used to bind the packages and pallets horizontally and vertically, so as to prevent the packages from shaking during transportation. The steel strip has high tensile strength and low tension relaxation. It is suitable for the circulation environment under various harsh conditions such as sunlight, heat and cold. However, it is not corrosion-resistant and easy to rust. It can not be used for the fastening of flexible packaging. It is suitable for the fastening of rigid outer packaging containers such as wooden cases

plastic strapping belts such as polyethylene, polypropylene, polyvinyl chloride, polyester and polyamine are light, non rusting, non absorbent and elastic. They are suitable for strapping cartons and corrugated cartons. Two problems should be paid attention to when using plastic belt to bind the packing box. On the one hand, the tension should be moderate to avoid belt breakage; On the other hand, the deformation of the fiber box should be reduced as much as possible on the premise of ensuring the fastening of the fiber box

(2) gluing

gluing is a non binding fastening method, which is suitable for the fixed stacking of paper packages on the tray. It can be applied by brushing adhesive or adhesive tape on the surface of the container, but the surface of the container shall not be damaged during unloading

(3) shrinkable packaging

shrinkable packaging is a method of wrapping pallets and packages with plastic film with heat shrinkable performance, and then heating them quickly. The packaging film shrinks by itself and clings to the packaged parts according to a certain ratio, which is worth looking forward to the development of new material industry. It is specifically divided into four steps: wrapping, heat sealing, shrinkage and cooling. Commonly used shrink films include PE, PP and PVC films. For the packaging of large pallets, polyvinylidene chloride, polyester and polyamine films with higher strength are commonly used. Compared with strapping packaging, shrink packaging has good overall performance and can effectively prevent looseness and damage during handling

(4) stretch packaging

stretch packaging is a kind of fastening packaging method for packaging by stretching the film around the tray and packaging through the action of mechanical force and using the self-adhesive and elasticity of the film after stretching. Commonly used stretch films include PVC, LDPE, EVA (ethylene vinyl acetate copolymer) and LLDPE (linear low density polyethylene) films. Although the moisture resistance of stretch packaging is worse than that of shrink packaging, it can replace shrink packaging in palletized packaging, which is a promising packaging technology

(5) edge protection (edge protection)

edge protection is divided into non-metallic and plastic edge protection, which is used for edge protection of paper reinforcement (such as cover plate and guard plate) and carton. Metal edge expansion is used for edge protection of wooden boxes and wooden reinforcements (such as corner braces and frames). Both metal and non-metal ribs are placed under the binding belt, which is convenient for binding with the binding belt

3 containerized transportation

modern international transportation industry widely uses containers for the transportation of products or packages, and has realized container standardization technology and management. Container transportation is a group transportation tool and method with sufficient strength, which can ensure the transportation safety of products or packages and minimize the damage of products

3.1 classification

containers can be divided into aluminum containers, steel containers and FRP containers according to their materials. Table 2 shows their performance comparison

Table 2 performance comparison of containers of different materials

Project stability, pressure resistance, utilization rate, operability

Simple overlap is poor, high and simple

staggered type is better, high and simple

vertical and horizontal type is better, high and simple

rotary type is better, high and low, simple

3.2 containerized transportation

containerized transportation is a safe, reliable and efficient transportation method, On the second day of transportation, Suning's share price soared without suspense. Two aspects should be paid attention to in packaging:

(1) actively implement ISO standards and give priority to containers of four specifications: 1AA, 1cc, 1DD and 5D. 1AA and 1cc are suitable for international transportation, and 10d and 5D are used for domestic transportation

(2) flexibly select the shape and structure of the container according to the type and quantity of specific products or packages. For example, bulk containers are used to transport powder and granular products in bulk, and ventilated containers are suitable for fresh food and perishable food; General purpose containers are suitable for the transportation of industrial products or packages with the most extensive materials in the chemical industry

4 transportation protection and handling protection of packages

in the process of transportation, the protection of pallets and containers is also an important factor affecting the safe transportation of packages. The protection methods of pallets and containers should be analyzed from two aspects: transportation protection and loading and unloading protection

4.1 transportation protection

the best way to realize transportation protection is to keep the gap between containers or pallets in freight cars and other transportation equipment very small. This method can not only avoid collision, but also reduce the damage of edges and corners. For this purpose, blocking pads can be used. The blocking pad is an inflatable air bag. The pad filled with air is placed in the freight car, container, truck or cargo ship to fill the gap between containers or pallets and between containers or pallets and transportation equipment, so as to protect the packaging in the container or on the pallet. When using the blocking pad, first place it empty in the space to be blocked, and then inflate it with air pressure. The charging/suction gun with barometer is connected with the charging gate through a relatively long rubber tube, which is convenient for operation. The consignee can discharge the air in the blocking pad with a charging/suction gun and take it out of the blocking space for storage, which can be reused. Generally, the blocking pad can be reused for 30 ~ 40 times, which is economical and reliable

4.2 loading and unloading protection

as the most important handling machinery in the handling process, forklift has a direct impact on the loading and unloading protection of containers or pallets. During forklift operation, the container or pallet must be isolated from the ground with cushion blocks or leave a gap between the package and the ground to ensure that it can be lifted by forklift. When loading and unloading containers or pallets, the load center of the forklift must be considered to avoid tilting accidents. In the process of handling, the external shape of containers or pallets is often an important factor affecting the safety of loading and unloading. Only after the specification (type, shape and size) of the container or pallet is determined can the handling method be determined. (end)