Introduce an advanced packaging container - convenient bucket

The convenience bucket is also called the multi-ear bucket lifting bucket. It is the most widely used international medium-sized industrial packaging bucket with a capacity between 18-22 liters.
In the Second World War, it was a military barrel of the United States. After the war, Japan first copied it and used it in industrial packaging. It has become one of the most popular packaging barrels. In the mid-1970s, Ningbo, Zhejiang province began to produce the first convenience barrels in a semi-mechanical way, and then began production in the suburbs of Shanghai. In the late 1970s, Tianjin designed and manufactured a relatively advanced production line, which was produced in batches on an industrial scale.
The convenience bucket is introduced as follows:
I. Overview:
The biggest feature of the convenience bucket is that the bucket is conical, the diameter of the bucket top is about 13.0 mm larger than the bottom of the bucket, and the top of the bucket is rolled into a circular tube with a diameter of about 10 mm, which makes the bucket top have better rigidity. Fully open, empty barrels can be put together one by one and put in order to save the warehouse. In the space of 1 meter x 1.2 meters x 0.3 meters, the cylindrical buckets with the same bottom area can only be placed in nine, while the convenience buckets can be placed in 36, and the capacity is increased by four times.
After filling, convenient buckets can be stacked vertically, while cylindrical buckets can only be coded as triangles or trapezoids. Therefore, the same warehouse, convenient barrel can be multi-yard or multi-transport 25% -50%. (See Figure 1)

Another feature of the convenience bucket is that it has two thick ribs (see Figure 3). A rib on the top of the barrel can protect the top tube from being broken, and the bottom one can make the rib not too tight when it is placed, so it can be easily pulled out. Thanks to these two stiffeners, the stiffness of the barrel is greatly increased, so that the barrel material can be greatly reduced. At present, Japan, Western Europe, North America and other countries, 20 liters of convenient barrels generally use 0.3-0.4 mm sheet metal production, China's iron bucket with the same capacity, more than 0.5 mm in thickness, using convenient barrels can save 20% of the plate.
Convenient barrels are fully open, so when filling, the speed can be faster and it is also easy to automate. When the barrel top and the barrel body are assembled, they are fastened by clamps, which is easy to open and does not damage the barrel body when it is opened. In this way, the contents can be stirred and poured during the construction. After use, the hand barrel is not damaged, and the user can handle it easily, which is beneficial to recycling or changing to civil use. So this is a good packaging bucket.
The following describes one of the most popular barrel types in the world.

Figure 6 Note: T - roll thickness (material 0.34mm, roll thickness 2.00mm; material 0.4mm, roll thickness 2.20mm; material 0.5mm, roll thickness 3.30mm. Tolerance +0.20mm, -0.10mm)
W——web (5.0±0.5mm)
C - flange depth (1.10 ± 0.2mm)

Second, the shape and size: (Figure 4 - Figure 8)
The standard type of convenience bucket is 20 liters. Due to the different weight of the packaging, there are two variants, namely 18L and 22L, in the case of the top of the bucket, the bottom of the bucket, and the constant diameter. Its size is shown in Table I and Table II.
Table 1: Standard type

Table II: Variants

Third, raw materials:
1, barrel, barrel bottom and barrel top, with no tin plate, cold pressed sheet, nominal thickness of 0.34 mm, its mechanical properties: yield point: 32 kg / mm 2, tensile stress 37 kg / mm 2.
2, handle ears: tin plate, nominal thickness: 0.4 mm.
3, ring: galvanized iron wire, diameter φ3.74 +0.04-0.00 mm, tensile strength: 45-95 kg / mm 2
4, grip: polyethylene.
5, sealant: applied to the seaming at the bottom of the barrel to prevent leakage, in our country more than the use of brown sugar bone limbs, my foreign trade packaging research institute successful 812 sealant effect is also very good.
The foreign sealant formula is:
Synthetic Rubber (SBR) - 35%
Strengthened additives - 27%
Tackifier - 2%
Ammonia - 0.2%
Water - 35.8%
6. Liner: Filled into the U-shaped groove in the top of the barrel (Figure 9). It acts as a sealing gasket when it is sealed. It requires elasticity, and it can not undergo chemical changes with the contents of the barrel. With the different contents of the barrel, there should be different formulas.
Now introduce a recipe for petrochemical products:
Vinyl chloride resin - 40%
2-Ethyl-hexyl-phthalic acid adipic acid - 40%
Iron oxide, germanium dioxide, barium sulfate - 15%
Foaming agent - 5%
Mix, flex, and heat at 175°C for 2-3 minutes.

Fourth, quality inspection and standard Huai:
The standards for convenience buckets have been stipulated by foreign countries and are divided into three levels, namely H, M, and L.
Grade H: Steel thickness O.6mm
M level: steel thickness O; 5mm
L level: steel thickness O.4mm
Different inspection standards are used for different levels of convenience buckets. Usually the following five kinds of tests are also performed:
1. Air tightness test:
The method is to block the barrel mouth with a rubber stopper, and then put the barrel in a sink, and then pass in compressed air to check for leaks. The ratings and air pressure regulations are given in (Table 3).
Table 3: Levels and Air Pressure Gauges

2. Hydrostatic test:
Fill the bucket with water and use a water pump to drive the high-pressure water into the bucket. Use this method to test the sealing performance of the bottom of the bucket, the top of the bucket, and the lid. According to the different pressures in the mouth, different regulations were made.
3. Drop test (see Figure 10)
The test bucket (filled with 98% of full water) from a height of 1.2 meters, to a thickness of 15mm or more on the steel plate, the barrel welding site toward the steel plate under the corner, after five minutes to check for leaks.

4. Decompression test:
Extract the air in the barrel to check the barrel deformation under atmospheric pressure.
5. Load test (see Figure XI):
In order to measure the vertical weight of the bucket, the weight it can bear, and the height of the stack.

V. Sealing:
Special clamping clamps are used for clamping. This kind of clamp has many productions in China.
Sixth, postscript:
Convenience barrels have been widely used in foreign countries, and China has also begun batch production. Relatively speaking, we use a smaller quantity. The main reasons are technology and price.
Process: It is less familiar with the expansion cone process and less experienced. According to the use situation of some factories in Tianjin, as long as there is a 20-ton four-column hydraulic press (this type of hydraulic press has already been mass-produced in China, and the technology is completely passed through), a multi-cylinder expansion cone mold can be solved. This bulging process has no technical difficulties in use.
In other aspects, it is a traditional barrel making process in China, and its equipment can be used to produce convenient buckets. Of course, mass production requires more investment and special equipment.
Followed by higher prices. The convenience bucket has a galvanized iron wire loop, a plastic handshake and a seal, which increases the cost by about 10%. As mentioned earlier, the barrel body is thinner and the cost can be kept flat.
In terms of total economic benefits, convenience buckets are larger than traditional cylindrical drums. This is no problem. Therefore, we recommend using a large number of convenient buckets.