Common classifications of quantitative packaging scales

　　Quantitative packaging scale (also known as packing scale or filling scale) is an active weighing device that actively divides large quantities of bulk materials into small proportional loads of equal mass according to a predetermined order and quantitative value. It is suitable for occupations such as grain and feed to carry out fixed value weighing of exported goods.

　　When selecting a quantitative packaging scale

　　Firstly, it is necessary to understand the major categories of packaging scales. Packaging scales are often classified based on their layout, that is, according to their adaptability to materials; It can also be classified based on the size of the packaging and different production process requirements.

　　1. Classify according to production process requirements

　　(1) Net weight quantitative packaging scale. When using this type of scale, the materials are weighed in the weighing hopper and then packed into packaging bags, which improves the measurement speed and accuracy.

　　(2) Gross weight quantitative packaging scale. This type of scale operation uses packaging bags as weighing carriers, with materials directly entering the packaging bags for weighing. The equipment layout is simple, and the total height decreases.

　　(3) Mobile quantitative packaging scale. This type of scale arranges the scale body, conveyor, sewing machine, air compressor, dust collector, dryer and other equipment on a mobile cart, which can replace the workplace at any time.

　　(4) Fixed quantitative packaging scale. This type of scale places the scale body under a fixed compartment, cooperates with conveyors and sewing machines, and uses centralized air sources and dust removal equipment for fixed value packaging.

　　2. Classify by the number of weighing buckets

　　(1) Double scale bucket type. The double bucket packaging scale can meet the needs of fast packaging. This type of packaging scale often uses gravity feeding method, and with the replacement of two buckets for weighing, the required packaging time is greatly reduced.

　　(2) Single scale bucket type. This is a common method, and the commonly used packaging scale is the single scale bucket type. Some scales are made of stainless steel.

　　(3) No scale bucket type. Materials with high adhesion tend to adhere briefly to the hopper of the packaging scale, affecting the accuracy of packaging. If not sorted in a timely manner, they may also mold and deteriorate, resulting in substandard products.

　　The non scale bucket type packaging scale uses sensors directly connected to the bag clamping organization to weigh the packaging bag and materials together, thus avoiding the occurrence of this situation. Due to the lack of the height of the weighing bucket, the height of this type of weighing equipment has decreased.

　　3. Classify by packaging quantity and size

　　(1) Constant packaging scale. A packaging scale with a weighing range of 20-50kg is called a constant packaging scale. Packaging bags with a weight range of 20-50kg are of moderate size, easy to stack, and convenient to transport, so this type of packaging scale is widely used.

　　(2) Medium sized packaging scale. A packaging scale with a weighing range of 5-20kg is called a medium weight packaging scale.

　　(3) Small scale packaging scale. A packaging scale with a weighing range of 1-5kg is called a small quantity packaging scale. Because the packaging quantity is small and the error tolerance is small, this type of packaging scale requires careful selection of sensors.

　　4. Classify by feeding method

　　(1) Belt feeding type. This method uses a conveyor belt feeder for packaging scale feeding, which has the advantages of simple layout, smooth operation, and power saving. The speed of feeding is controlled by pneumatic gate blocking equipment to control the thickness of the material layer. For granular materials with good fluidity and ordinary powders, it has outstanding universality and is currently widely used.

　　(2) Spiral feeding type. The use of auger feeding for packaging scales can overcome the defect of inadequate sealing of belt feeding tissues. There are two types of feeding machines: flat feeding machines and inclined feeding machines. The selection of inclined feeding machines is to overcome the self flow of materials. In order to achieve the desired effect, the outlet of inclined feeding machines should not be lower than the inlet. Usually, two large and fine winches are used to adjust the speed of feeding. When feeding quickly, the large and fine winches run together, while when feeding slowly, only the small winches run.

　　(3) Gravity feeding type. Gravity feeding is the use of the material's own quality to feed through free fall. Its advantage is that it does not require rated power, but requires good scattering of the material. Sometimes, in order to achieve uniform and smooth feeding, pneumatic loosening equipment is also used. The speed of feeding is usually controlled by the opening of the large and fine doors, which is suitable for granular materials with good fluidity.