Let’s see, I’m not an expert in the technical department. I’ll try to give you a simple explanation of each one. We have two types. First, there are the un-reinforced supports, which do not have a metal core, that’s why they’re called un-reinforced, and they are used for small movements. Then there are the reinforced supports, which have a metal core. The type of support is determined by the auxiliary steel elements that the support contains.
Type B is a support that is a steel and rubber sandwich, with the steel inside the support and not visible. The surrounding part is all rubber, whether it’s a rectangle, a square, and you only see the rubber, but inside there are layers of rubber and steel.
Then there is type C, which is the same as type B but with additional layers of steel either on top or at the bottom, providing support for welding or introducing bolts into the beams.
Next is type five, which is similar to type C, but instead of smooth plates, it has embossed plates. What does embossed mean? It means that the steel has a pattern so that when you place it in the structure, it doesn’t move.
Then there is type D, which are the supports with Teflon, used to move large structures, such as bridges, but for temporary purposes. They allow for sliding, that’s why they have a layer of Teflon. These elastomeric supports are not permanent.
For moving a cable-stayed bridge, for example, there is a construction system that slides on supports of this type.
Then there are the anti-seismic supports, which have many more layers of steel and rubber, and they also have a lead core, etc.
The supports can be manufactured using different types of rubber as well. For example, in the United States and America in general, they comply with a regulation and usually use chloroprene. In Europe, natural rubber is more commonly used. So, different materials are also used, and the steels come in different grades, etc.