The basic information of heat shrinkable tubing, what is the general specification of heat shrinkabl

Performance: It has the functions of high temperature shrinkage, soft flame retardant, insulation and anti-corrosion. It is widely used in the insulation protection of various wiring harnesses, solder joints and inductors, and the anti-rust and anti-corrosion of metal pipes and rods. Voltage level 600V.

Polymer materials have to go through glass-high elasticity with low to high temperature, and the performance is close to plastic in glass state and rubber in high elastic state.

The material used in the heat shrink tubing is glass at room temperature and becomes highly elastic when heated.

Use: During production, the heat shrink tubing is heated to a highly elastic state, a load is applied to expand it, and it is quickly cooled while maintaining the expansion to make it enter the glass state, and this state is fixed. As soon as it is heated during use, it will become highly elastic, but at this time, the load is gone, and it will retract.

Shrinkage ratio: 2:1

Shrink temperature: 84 120

Operating temperature: -55 125

Fire rating: VW-1

Heat shrinkable tubing is an innovative polymer material first invented by the United States in the 50s of the last century, and its main function is insulation protection. After more than 50 years of development, heat shrinkable tubing has been derived from a variety of materials to meet the needs of customers in different fields. For example, the heat shrinkable tubing produced by Walsing Company includes EVA heat shrinkable tubing, PTFE heat shrinkable tubing, PVDF heat shrinkable tubing, silicone rubber heat shrinkable tubing and other insulating sleeves.

1. The specifications of the heat shrinkable tube are:

The common specification of heat shrinkable tubing is 100 mm, which is a special type of polyolefin heat shrinkable tubing, also known as EVA material, the outer layer is high-quality and soft glued polyolefin material, and the inner layer is hot melt adhesive. The outer material has good insulation, corrosion resistance and wear resistance, and the inner layer has a low melting point, excellent water tightness, and good viscosity.

What are the precautions for choosing high-quality pipes.

There are many types of pipes on the market, and we need to take into account all aspects of health performance, service life, flexibility, etc., so as to ensure excellent quality and reduce the probability of problems.

1. When purchasing, we must pay special attention to its health performance, if the health is not up to standard, it will affect human health, under normal circumstances, the inner wall of the plastic pipe must be smooth, but also to ensure that there is no dirt, and there will be no heavy metal pollution.

2. Then we have a general understanding of the service life of the pipe, if the service life is not long, then the maintenance cost or replacement cost will increase in the future, which will make the owner's economic pressure greater, thus affecting the usual use.

3. When purchasing pipes, we must ensure that its flexibility is good, if the flexibility is poor, then its force can not be obtained, and it is easy to be damaged, so that it must be repaired or updated again, if the toughness is excellent, then the probability of water leakage can be reduced.

1. There are two ways to express the specifications of heat shrinkable tubes:

1. It is expressed by diameter. 100 indicates a heat shrink tubing with a diameter of 100mm.

2. It is represented by a folded diameter. A fold diameter of 100 indicates a heat shrink tubing with a flat width of 100 mm. Half of the circumference.

2. Heat shrinkable sleeve is a special polyolefin heat shrinkable sleeve, which can also be called EVA material. The outer layer is made of high-quality and soft cross-linked polyolefin material and the inner layer of hot melt adhesive, the outer layer of material has the characteristics of insulation, anti-corrosion, wear resistance, etc., and the inner layer has the advantages of low melting point and high adhesion of waterproof sealed box.

When making plastic products, we often encounter the problem of shrinkage, so what are the influencing factors of plastic shrinkage?

1.The effect of plastic structure on the shrinkage of the product.

1) The shrinkage rate of thick-walled plastic parts is greater than that of thin-walled plastic parts (but most plastic 1mm thin-walled parts have a larger shrinkage rate than 2mm, which is due to the increase of melt resistance in the cavity of the mold bridge);

2) The shrinkage rate of the insert on the plastic part is smaller than that without the insert;

3) The shrinkage rate of complex plastic parts is smaller than that of simple shapes;

4) The shrinkage rate of the height direction of the plastic part is generally smaller than that in the horizontal direction;

5) The shrinkage rate of slender plastic parts in the length direction is small;

6) The shrinkage rate of the size in the length direction of the plastic part is smaller than that in the thickness direction;

7) The shrinkage rate of the inner hole is large, and the shrinkage rate of the shape is small.

2.The effect of plastic properties on the shrinkage of the product.

1) The shrinkage rate of crystalline plastics is greater than that of amorphous plastics;

2) Plastic with good fluidity, small molding shrinkage;

3) When filler material is added to the plastic, the molding shrinkage rate decreases significantly;

4) Different batches of the same plastic, the molding shrinkage is also different.

3.The effect of plastic mold structure on heat shrinkage.

1) The gate size is large, and the shrinkage rate is reduced;

2) The shrinkage rate decreases in the vertical gate direction and increases in the parallel gate direction.

3) The shrinkage rate of the gate away from the gate is smaller than that of the proximal limb elimination gate;

4) The shrinkage rate of the plastic parts with mold restrictions is small, and the shrinkage rate of the plastic parts without restrictions is large.

4.The effect of molding process on the shrinkage of plastic products.

1) Barrel temperature: When the barrel temperature is high, the pressure transmission is better and the shrinkage force is reduced. However, when using a small gate, the shrinkage rate is still large due to the early curing of the gate. For wall thickness parts, the shrinkage is still large even if the barrel temperature is high.

2) Feeding: In the molding conditions, the feeding should be minimized to keep the size of the plastic part stable. However, if the feed is insufficient, the pressure cannot be maintained, and the shrinkage rate will increase.

3) Injection pressure: Injection pressure is a factor that has a great impact on the shrinkage, especially the holding pressure after the filling. In general, when the pressure is high, the shrinkage rate is smaller due to the high density of the material.

4) Injection speed: Injection speed has little effect on shrinkage. However, for thin-walled parts or very small gates, and when using reinforced materials, the shrinkage is small due to increased injection speed.

Mold temperature: Usually the shrinkage rate is also greater when the mold temperature is higher. However, for thin-walled plastic parts, the flow resistance of the melt is small when the mold temperature is high, and the shrinkage rate is smaller.

5) Molding cycle: There is no direct relationship between molding cycle and shrinkage. However, it should be noted that when the molding cycle is accelerated, the mold temperature and melt temperature will inevitably change, which will affect the change of shrinkage.

6) Mold temperature: The higher the mold temperature, the greater the shrinkage.

1 All refers to the ratio percentage of the inner diameter of the heat shrink tubing after complete shrinkage to the inner diameter before shrinkage.

For example, the diameter of the heat shrinkable tube is 6mm, and the inner diameter is 3mm after full shrinkage, which is 5.

The shrinkage rate corresponds to the shrinkage multiple, and if the shrinkage rate is 50, the shrinkage ratio is 2:1.

I don't know what to refer to.

There are many heat shrinkable tubes in the market, and most of the manufacturers of heat shrinkable tubes are distributed in Guangdong, Jiangsu and Wenzhou, and the application range can be said to be very wide, such as: automotive wiring harnesses, electronic components, communications and marine waterproof use, wiring harnesses and other wires and cables are used the most, because heat shrinkable tubes are tubular and are used along the wire sleeve, and the thickness and length can be cut at will according to the actual application needs;

Tools Raw materials.

Heat shrink tubing of appropriate lengths.

Heating tools: heat guns, flame spray guns, etc.

Before use, you need to prepare the correct specifications of heat shrinkable tubing and heating tools, the specifications of heat shrinkable tubing are generally slightly larger than the cable to be protected, as long as it is slightly larger and can be tightened, so that the specifications are the smallest without delaying use, so that the cost budget is also the lowest;

Then use a heating tool (heat gun) to heat one end of the heat shrinkable tube evenly to make it shrink gradually, and it may need to be fixed by hand or other objects simply before shrinking, and when it is naturally fixed a little, you can release your hand to remove the fixation, at this time, you can heat shrink from beginning to end until all the shrinkage is completed, and completely wrap the connector that the cable wants to protect;

Precautions. The size of the heat shrinkable tube should not be too large, otherwise the heating time will be too long, and if the specification is too large, it may not be tightened;

When heating, pay attention to controlling the temperature and heat, heating from one end to the other, or emptying the air in the pipe from the middle to both sides, otherwise there will be bulging;

The insulation at the joint of the wire is the heat shrinkable tube, which is divided into phase colors and plays a good insulation, or waterproof effect, and heat shrinkable tubing is not common in other places.

Heat shrinkable tube will shrink when heated, such as using an electric hair dryer to blow the heat shrinkable tube, the heat shrinkable tube will shrink, the general circuit is used more, you can see that in many circuits, the insulation of the joint of the wire is the heat shrinkable tube, which plays a good insulation, or waterproof effect, and other places are not common with heat shrinkable tubes.

The heat shrinkable tubing mainly plays a protective role in the desired things (mainly: insulation, flame retardant, anti-corrosion, and other protective roles). It is mainly used in electricity, as well as in the electronics industry.

Because the heat shrinkable tube material is made of cross-linked polyolefin, the strength of the cross-linked molecular bond determines the selection of the heat shrinkable tube, if the degree of cross-linking is not high, you can choose to fill the product with recycled materials, due to the use of plasticizers, you can imitate the performance of the raw material product, but the shrinkage rate is not high, and the shrinkage force (molecular bond is not strong) is not enough; If the cross-linked molecular bond is strong and the shrinkage rate is large, it is necessary to select the products produced by raw materials, pay attention to the size when selecting, and choose within the range of 70-80% shrinkage of the heat shrinkable tube, such as the 20mm diameter heat shrinkable tube is suitable for 14-16mm diameter objects, and the 5mm diameter heat shrinkable tube is suitable for the diameter of the object.

Temperature resistance grade, flame retardancy, shrinkage, color, shrinkage temperature, final shrinkage temperature, service temperature. Supplements are welcome.