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Silicone part 2

Silicone articles such as hoses, profiles, cords, fittings are produced using the extrusion method, which allows great flexibility in the selection of the shape and dimensions of the finished product, both typical shapes with a rectangular or round cross-section and specific ones based on individual customer requirements.Each inquiry is considered individually.

The basic properties of silicone products, such as a wide range of thermal resistance, high flexibility, ease of obtaining cleanliness, and the approval of a large part of mixtures for food contact, allow the use of silicone products in many industries, both light and heavy and in the construction industry. Silicone products are used by companies from the food industry, thanks to their sterility also in the pharmaceutical and medical sectors, as well as the automotive, textile, packaging and industrial plant manufacturers.Silicone products are also available in the form of solid and foamed slabs.Foamed silicone panels, thanks to their sponge-like structure, are perfect for making seals that require a good fit to the surface to be sealed.

Solid silicone panels, like profiles, are used in many industries. Since solid plates are approved for contact with food and drinking water, they are particularly popular in the food industry, e.g. confectionery, bakery, wine and, thanks to their heat resistance to -60°C, also in the cooling industry. The product is non-flammable (even if it exceeds the permissible temperature for a long time, it will not ignite, only crumble) and resistant to salts and alcoholic substances, so it is used not only in the food industry but also in packaging, automotive, electronics and many others. The total range of thermal resistance oscillates in the range -60 +200 degrees C. Standard hardness of solid silicone plate is 60ShA, 18ShA foamed, 1200mm wide solid slab, 1000mm foamed, thickness range from 2 to 12mm.

Standard silicone slabs:

Solid semi-transparent slabs - approved for contact with food on the basis of PZH / FDA approvals
Solid red slabs - industrial approval (food contact is not permitted)
Foamed white slabs - industrial approval (not permitted for contact with food)

Silicone rubbers that vulcanize at higher temperatures are processed by equipment such as injection moulding machines, extruders, rolling mills. Ready-made mixtures containing a vulcanizing agent (most often organic peroxides are used - often in the form of 40-50% pastes with silicone oil, mixtures with chalk or kaolin) are plasticized in a rolling mill to prepare for further processing. Sometimes the mixture is vulcanized by radiation. Moulding in the press usually takes place at a temperature of 115-175oC, in the case of 200-235oC injection moulding - such methods are preferred in the production of simple moulds, more complex shapes require the method of extrusion. The extruded parts must be vulcanised in a steam boiler or hot air. The calibrating method (shaping the mass by rolling between the rolls) is most often used in the production of silicone slabs, similarly to extruded elements, silicone slabs also require vulcanization (most often rolling rolls are combined in one insert with a heating vulcanizing element). In the case of porous silicone slabs or profiles, a blowing agent is added to the mixture. Pre-vulcanized mixtures must be preheated at a temperature exceeding the permitted exposure temperature of the finished product.

Silicone coatings are also used as a coating of metal rollers, rolls, drums, conical rollers working as elements of a machine set in many branches of industry - in food, furniture and textile industries, as well as specialized blends also in the printing and paper industry. The silicone mixture coating (coating with the required thickness) is applied to the core of the roller, then the process of vulcanization and further processing looks similar to that of silicone plates. At the end of the cycle, the coating is ground to the required size and polished. Mixtures used for roller linings have a wide range of thermal resistance and hardness, some of the mixtures available on the market are approved for contact in the food industry. It is possible to cover both new rolls with silicone and to regenerate the coating of already used rollers.

As with the PTFE coating, the silicone mixture can be applied to baking trays, moulds, baguette baking forms. The coating is a separating layer of non-stick layer, thanks to which the baking process does not require greasing the sheets with fat. Silicone coatings are particularly recommended for baking sweet products with a high sugar content. Depending on the requirements, the most commonly used coating is the thermosetting one, which is ideal for baking sweet cakes, but due to the high temperature at which the silicone coating is cured, only materials that can be fired at a temperature of about 350oC can be covered. The available vulcanizing coating allows for silicone coating of surfaces that do not have high thermal resistance. This type of coating is mainly used to cover the baking forms of lightweight bread rolls, baguettes.Siliconizing various types of baking trays and forms has a positive effect on the quality of baked goods, saves time previously used for lubricating the moulds with fat, and thanks to the reduction of fat the finished product has a lower calorific value, the silicone coating reduces to a minimum the time spent on washing trays and moulds.Siliconizing also affects the economics of a confectionery or bakery - the coating allows for up to 3000 baked goods. Trays the silicone coating of which has worn out can be regenerated. The re-siliconizing allows for further use of the trays.

Silicone is widely used in many industries as well as in households, in the form of seals in household appliances, window seals in many others.