Introduce an advanced packaging container - convenient barrel

Zhang Yusheng

Convenient barrels, also called multi-ear lids, are the most widely used medium-sized industrial packaging barrels in the world, with a capacity of 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 applied it to industrial packaging. It has become one of the most popular packaging barrels. In the mid-1970s, Zhejiang Ningbo began to produce the first batch of convenient barrels in a semi-mechanical manner, and then began production in the suburbs of Shanghai. In the late 1970s, Tianjin designed and manufactured a relatively advanced production line, and produced the packaging drums in batches on an industrial scale.

The convenient bucket is now introduced as follows:

I. Overview:

The most convenient feature of the convenient bucket is that the bucket is conical, the diameter of the top of the bucket 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, so that the top of the bucket has better rigidity. Fully open, empty barrels can be put together one by one, coded to save the warehouse. In the space of 1 m × 1.2 m × 0.3 m, the cylindrical barrel with the same bottom area can only be placed in 9 pieces, while the convenient barrel can be placed in 36 pieces, and the capacity is increased by four times.

After filling, the convenient buckets can be placed vertically, while the cylindrical buckets can only be coded into triangles or trapezoids. Therefore, the same warehouse, convenient bucket can be multi-coded or transported 25% to 50%. (See Figure 1)

Another feature of the convenient bucket is that there are two large ribs (see Figure 3). A rib at the top of the bucket can protect the top coil from being broken. The lower one can make the rib not too tight when it is placed, which is easy to pull out.

Thanks to these two reinforcing ribs, the rigidity of the barrel is greatly improved, and the material of the barrel can be greatly reduced. At present, in Japan, Western Europe, North America and other countries, 20-litre convenient barrels are generally made of 0.3-0.4 mm thin plates. The thickness of iron drums of the same capacity in China is more than 0.5 mm, and 20% of the plates can be saved by convenient barrels.

Conveniently the barrel is fully open so that it can be loaded faster and easier to automate. The top of the barrel and the barrel are fastened by means of clamps, which is easy to open and does not damage the barrel when opened. In this way, the contents can be stirred and inverted, and after use, the barrel is not damaged, and the user is easy to handle, which is beneficial for recycling or changing to civilian use. So this is a good bucket for packaging.

The following is a description of the most popular barrel type in the world.

Note: The dimensions in Figure 6 are: T: roll thickness (+0.20/-0.10), there are three kinds of conditions, (1) material thickness 0.34mm, T=2.00mm; (2) material thickness 0.40mm, T=2.20mm; (3) The material thickness is 0.5 mm and Y = 3.30 mm. W: A roll (5.0 ± 0.5 mm). C: flange depth (1.10 ± 0.2 mm)

Second, shape and size: (Figure 4 ~ Figure 8)

The standard type of convenient bucket is 20L. Due to the different specific gravity of the package, there are two variants, namely 18L and 20L, in the case of the top of the bucket and the bottom of the bucket. The dimensions are shown in Table 1 and Table 2.

Table 1 standard type

Table 2 variant size

Third, raw materials:

1. The barrel body, the bottom of the barrel and the top of the barrel are made of non-tinned sheet and cold pressed sheet with a nominal thickness of 0.34 mm. The mechanical properties are: yield point: 32 kg/mm ​​2 and tensile stress 37 kg/mm ​​2 .

2. Handle ear: tinned sheet, nominal thickness: 0.4 mm.

3. Lifting ring: galvanized iron wire, wire diameter φ3.74+0.04/-0.00 mm; tensile strength: 45-95 kg/mm2.

4. Grip: Polyethylene.

5. Sealant: applied to the seam at the bottom of the barrel to prevent leakage. In China, the use of brown sugar bone glue, the successful production of 312 sealant by the Foreign Trade Packaging Institute is also very good.

The foreign sealant formula is:

Synthetic rubber (SBR): 35%

Fortified additive: 27%

Tackifier: 2%

Ammonia water: 0.2%

Water: 35.8%

6. Liner: Filled into the U-shaped groove on the top of the bucket (Fig. 9). It acts as a sealing gasket when sealing. It requires elasticity and does not change chemically with the contents of the barrel. With the bucket

There should be different formulations for the contents of the contents.

Now introduce a formula for petrochemical products:

Vinyl chloride resin: 40 96

2-ethyl-monohexyl phthalic acid adipic acid polyester: 40%

Titanium oxide, cerium oxide, barium sulfate: 15%

Foaming agent: 5%

Mix and cast and heat at 175 ° C for 2-3 minutes.

Fourth, quality inspection and its standard:

Foreign countries have stipulated the standards for convenient barrels, which are divided into three levels, namely, H, M, and L.

H grade: steel plate thickness 0.6mm

M grade: steel plate thickness 0.5mm

L grade: steel plate Hui 0.4mm

Different inspection standards are used for different levels of convenient barrels, and the following five tests are usually performed:

1. Airtight test

The method is to block the mouth of the barrel with a rubber stopper, then put the barrel into the water tank, and then introduce compressed air to check for leaks. See the level and air pressure regulations (Table 3).

Table three levels and air pressure

Note: For the screw cap, the pressure is 2.1Kg/cm2; for the crown cap, the pressure is 0.5Kg/cm2.

2. Hydraulic test:

Fill the bucket with water, then use a water pump to pump high-pressure water into the bucket. Use this method to check the sealing performance of the bottom of the bucket, the top of the bucket and the flap.

Different regulations are made according to different flap pressures.

3. Drop test (see Figure 10)

The test bucket (filled with 98% of water) was placed from a height of 1.2 m to a steel plate having a thickness of 15 mm or more, and the welded portion of the barrel was placed under the corner of the steel plate, and the leak was checked after five minutes.

4. Decompression test:

The air in the barrel is taken out to check the deformation of the barrel by atmospheric pressure.

5. Load test (see Figure XI),

To measure the weight that can be withstood when the barrel is vertically placed, and to specify the height of the stack.

V. Sealing

Clamped with a special clamping clamp. This type of clamping pliers has been produced in Shanghai and can be ordered.

Six, postscript:

Convenience barrels have been widely used abroad, and China has also started batch production. Relatively speaking, the quantity we use is relatively small, mainly due to both process and price.

Process: It is not familiar with the expansion cone process and has less experience. According to the use of factories in Tianjin, as long as there is a 20-ton four-column hydraulic press (this hydraulic machine has been mass-produced in China, the technology is also completely cleared) with a set of multi-petal-expansion cone mold, it can be solved. The process and theory of this expansion cone has been published in the No. 6 "Coating Industry" in 1980, and there is no technical difficulty in use.

Second is the higher price. The convenience bucket has an increase of about 10% in cost due to the addition of a galvanized iron wire loop, a plastic handshake and a sealing ring. As mentioned earlier, the barrel is thinner and the cost is flat.

In terms of total economic benefits, the convenience bucket is larger than the traditional cylindrical drum, which is no problem. So we recommend a lot of convenient buckets.