Drug packaging container drum design (on)

The packaging containers used for pharmaceutical raw materials and pharmaceutical exports in China are mostly packed in paper drums. Due to their high strength, elasticity, and non-oxidative pollution, compared to steel drums, they have anti-static properties, light weight, easy recycling, short processing cycles, and low manufacturing costs. Such advantages, generally welcomed by the pharmaceutical industry. Applications have also become more widespread, not only in the pharmaceutical industry, but also in the chemical, food, indigenous, hardware, minerals, building materials, electrical and mechanical and defense industries, a considerable part of which is used for packaging of export commodities.

The packaging container drums are divided into two categories, one is a full-paper drum, and the appearance is round and square. They are all made of high-strength cardboard and processed on a dedicated drum molding machine. Most of the cardboard raw materials used are Paper fiber and wood fiber. Therefore, it is easy to recycle and reuse. If it can be burned and no toxic gas is produced in case of emergency treatment, the whole paper drum can be called “green packaging” from its raw materials and the whole process of production process to the export. It is easily accepted by foreign merchants.

The structure of another type of paper bucket is reinforced with iron sheet at the upper and lower bottoms of the circular paper barrel. The upper and lower bottoms of the paper bucket are made of full paper or pentacholamulus and are reinforced with iron sheet under the same volume. The structure of the drum is higher than the full paper drum in terms of strength and weight. The structural design of the drum is as follows:

1. The raw material chosen should suit the requirements of the drum:

The structure of the barrel is multi-layered. The barrel is manufactured by the spiral winding method. The various indicators of the cardboard are related to the overall quality of the barrel. The general choice of the cardboard is 300-360 g/m2, in order to guarantee the barrel The strength and rigidity of the paperboard raw material are generally not less than 18N.m/g for a loop pressure strength of 300 g/m2, a burst resistance index of not less than 3.0kpa·m2/g, a transverse bending resistance of not less than 50 times, and moisture content. Not more than 10%.

2. Bucket strength and deformation design

In addition to the strength of the bucket, the thickness of the bucket and the axial force acting on the bucket are related to the raw material used. In the case where the material is determined and the circumference is constant, the bucket is standing. The compressive strength should be greater than 8000N, the lateral compressive strength is greater than 4000N, and the puncture strength is greater than 10N.

The deformation of the drum is related to the stiffness of the drum, that is, whether the rigidity coefficient at the time of design is reasonable. The size of the deformation of the drum is proportional to the side pressure and the circumference of the drum, and inversely proportional to the elastic modulus of the drum, the thickness of the drum, and the number of layers; that is, the greater the pressure acting on the drum, As the circumference grows, the larger the deformation of the bucket, the larger the elastic modulus of the bucket, the greater the number of layers and the greater the thickness, the less deformation. It follows that to make the paper drum stress small, the number of layers of the paper drum and the thickness of the paperboard should be increased. Whereas the stiffness coefficient of the paper drum is large, the stiffness of the paper drum is greater. Materials should be made of cardboard with high elastic modulus, a large number of layers with thick paper and relatively small diameter structures.

3. The design of the concave ring groove on the upper and lower part of the drum:

In order to enhance the strength of the paper drum, it is fixed on the paper drum and the lower mouth part is rolled with a concave ring groove, which is also called a barrel hoop. The hoop at the mouth of the barrel is called the hoop, and the hoop at the bottom (bottom) is called the hoop. The main functions of the hoop hoop are:

1 Ensure the strength of the bucket and keep the roundness of the bucket mouth.

2 Reinforce the sealer, which can make the lid and barrel well positioned and interchangeable.

3 Position the drum molding equipment (sealing machine) mold. The function of the lower barrel hoop is to fix the barrel body and the five-plywood into a firm whole. Therefore, whether the shape of the circular arc of the barrel hoop groove and the size design are reasonable or not have a great influence on the quality of the drum.

The designed barrel hoop groove is too deep and the arc curvature is small, and it is easy to break the barrel during the forming process; the barrel hoop groove is too shallow and the arc arc is too large, which directly affects the connection of the barrel bottom structure (with the barrel body). And in the process of molding the back cover, the deformation of the steel band is large, and the amount of the iron plate rolled up to the barrel body is relatively small, resulting in that the cardboard and the five-plywood board are not firmly bonded; therefore, when designing the arc shape size of the upper and lower hoop of the paper bucket, Choose the strength of the board, the thickness of the plywood, and the equipment used in the process of molding. (To be continued)