Industry Information

A Brief Discussion on the Differences between the Three Major Processes of Foamed Silicone Tube and Rubber Foaming by Manufacturers

  Foamed silicone tubes are called by people who are more familiar with silicone products, and silicone rubber foamed tubes are people who generally do not have much contact with silicone extruded products like to call it this way, while silicone rubber foamed tubes and rubber hair The bubble tube is only missing one word, which is very misleading. Because of one word, the product is completely inconsistent with the product requested by the customer. The appearance of these products is very similar. In short, the foamed silicone tube and the silicone rubber foamed tube belong to the same product name, while the foamed rubber tube is a completely different product. Today I will introduce to you the grievances and initial positioning of various products.
  First of all, foamed silicone tube and foamed silicone rubber tube are a kind of product, which we collectively call silicone. There are currently three mainstream production processes for foamed silicone tubes, which are conventional foaming process, oil foaming process, And the mandrel foaming process, currently only the conventional foaming process can achieve infinite length, the other two processes have production length restrictions, so if customers can't judge which material they belong to, they can choose according to their needs. Customers require products If the inner diameter control requirements are very high and the length is unlimited (for example, 300 meters per pcs or longer), then you need to choose the rubber foaming process. If your product has a length requirement such as 500mm long, 200mm long, you can choose silicone foam. bubble craft. Advantages of conventional foamed silicone tubes: Silicone can pass ROHS environmental protection requirements, and has a service life and high and low temperature resistance (-40~200° special foaming process 300°), and will not be particularly damaged under long-term ultraviolet radiation. Influence. But the foamed silicone tube is not perfect, we also need to know it clearly.
  Basic understanding of the three mainstream processes of foamed silicone tubes:
1. Conventional foaming process: unlimited length can be customized according to customer requirements, and the most extensive foaming density can be produced from 0.3 to 1.0. There are no special requirements, and special foamed silicone tubes can also be customized according to customer requirements. For example, flame retardant, high temperature resistance, etc., but it also has the disadvantage that it will have some impact on the inner diameter of the product during the long-term infinite production process, and it will be deformed if the inner hole is not round enough and there will be deviations in size. This kind of foaming process requires talc. The bottom of the product tends to have less sticky talcum powder, and it will fall off during vulcanization in the drying tunnel, resulting in very slight belt marks on the bottom.
Physical picture of conventional foaming process products:
2. Oil foaming process: This process does not need to go through talcum powder, but directly filters a layer of oily substances after extrusion from the machine head, because there is no need for talcum powder, so naturally there will be no belt marks. , the foamed silicone tube is filtered out of the oily substance and then immediately enters the drying tunnel to add sulfur. However, this kind of process has high requirements for product density. Generally, the foaming density should not be too low, and this kind of foaming process can Meet FDA food-grade certification requirements (Yutian company can improve FDA food-grade certification) and can also perform a variety of secondary processing techniques such as grinding, chamfering, silk screen, laser engraving, etc. The disadvantage is that it cannot produce infinite length, because in After oiling, the inner tube is stuck with oily substances, and when the temperature is higher in the vulcanization of the drying tunnel, the oily substances will form water vapor and adhere to the inner wall of the foamed silicone tube without volatilization (silicone is closed-cell foamed and sealed. ) to form high-temperature fog, so it is generally necessary to cut a section to let the volatilized mist disperse when producing 3~5 meters, so it cannot be infinitely long. The other is to cut a section when producing 3~5 meters and scrap it The rate is very high, which leads to the relatively high price of the oil foaming process (1. High density, 2. High scrap rate, 3. Many secondary processing procedures). The representative product is foamed silicone grips. , Bicycle silicone handles, fitness equipment silicone handles, etc.
Physical map of foaming products by oil furnace process:
3. Mandrel foaming process: This is a special foaming process with a very smooth and round surface, but the application field is relatively fixed, and it is often used on the appearance of the machine roller. It is also called a silicone foam leather cover. The foaming process cannot be infinitely long, and generally needs to be cut at about 3 to 5 meters. How to cut it according to the length required by the customer. In other words, the general roller has a length, so it is not a problem to use the foamed silicone tube of this process. Its advantage is that the outer surface of the foamed silicone tube will form a layer (smooth surface), which has good resistance to compression and other Features shared by foamed silicone tubes. Its main representative products are: silicone rubber foam roller for printers, silicone rubber roller for copiers, etc.
Mandrel foaming process product physical picture:
  Among these three processes, the conventional foamed silica gel and the oil furnace process will have fine particles on the surface after production, especially in the black foam tube. The particles are particularly obvious, which should be the oil furnace process. The foamed silicone tube has little effect on such particles as handle products, and many of them need to be polished to grind the surface so that the particles cannot be seen. The other conventional foamed silicone tube has no good way to solve this problem. In order to solve the problem of conventional foamed silica gel surface particles in the market, most of them use color change, such as changing to blue, Cyan, etc. can perfectly cover up the white particles. So if the customer needs a perfect one without secondary processing, the mandrel foaming process can be solved, because its surface is smooth and no talcum powder is used. The high caused many people to switch back because of the price.

With more than 20 years of production management experience, we insist on providing customers with high-quality foamed silicone tubes