Rubber profiles can be used as seals or to shield sharp edges. At HTR, we don't have any standard profiles. We develop an optimal profile for each application. Of course, we want the application to function optimally, but we also want to take into account wishes such as lifespan, assembly, etc. The tool investments for a rubber profile are relatively low compared to for example injection moulds. However, the minimum order quantity for rubber extrusion is often higher than expected. On the one hand, this is because a minimum amount of rubber compound has to be specially mixed. On the other hand, rubber extrusion lines are very long, which means that there is already a considerable start-up length from the setting of the line.
Silicone profiles can be used as seals or to shield sharp edges. At HTR, we don't have any standard profiles. We develop an optimal profile for each application. Of course, the optimal function is the one that's required in the application, but it also integrates requirements such as lifespan, fittability, etc. Based on temperature or resistance to certain influences, silicone material can be chosen for the profile. Silicone profiles can also be produced in different colours. In addition, material compounds may also meet food or medical application standards, for example.
Rubber is still one of the most commonly used materials for seals. The excellent elastic properties lend themselves perfectly to the sealing of a gap between two construction parts. If rubber is the right material for your seal, it must be determined which type of rubber is best suited for use. This depends on temperatures, loads, construction tolerances, life expectancy or the influence of UV, Ozone or chemical environments. That's why it's very important to match the functional requirements of the application with the specific properties of the different types of rubbers.
To make an application dustproof or waterproof, EPDM (Polyurethane), Silicone or other rubber group materials are often used as the sealing material. Nonetheless, a good seal is only possible for a number of applications if there's also a very low back pressure from the seal on the structure. The variation in the gap to be sealed by tolerances may also have a large variation. In these situations, a High-Performance Polyurethane seal can help. It has a very low counter-pressure and a large area in which this material can seal without damaging the material. As a result, it often gives a better result than the “conventional materials”.
Cellular rubber is closed-cell foams made of rubber. Cellular rubber is available in different hardnesses or densities. The densities are between 70 and 200 kg/m3. The hardness range varies from Shore OO 28 to 60. The types of rubber available in cellular rubber at HTR are: EPDM, neoprene, NBR, silicone. Cellular rubber is moulded into block shapes and then slit to the right thickness and connected to form rolls. As a result, there are glue connections every few meters in a roll. The sealing quality on these connections is less compared to the rest of the cell rubber. If desired these connections can be detected and taken out.
The vacuum forming of foam materials such as polypropylene, polyethylene, HDPE, EPP, EPS provides technically interesting possibilities for technical insulation parts. The thermoforming or vacuum forming of polypropylene material provides opportunities for lightweight structural parts. Vacuum forming has advantages in terms of mould costs but also has more limited possibilities in terms of geometry and degree of deformation compared to thermoforming. For both techniques, many types of materials and also composite laminates can be used. HTR has several lamination technologies to create different material combinations which can be thermoformed or vacuumformed.
Thermoforming foam materials such as polypropylene, polyethylene, HDPE, EPP, EPS provide technically interesting possibilities for technical insulation parts. The thermoforming or vacuum forming of polypropylene material provides opportunities for lightweight structural parts. Vacuum forming has advantages in terms of mould costs but also has more limited possibilities in terms of geometry and degree of deformation compared to thermoforming. For both techniques, many types of materials and also composite laminates can be used. HTR has several lamination technologies to create different material combinations which can be thermoformed or vacuumformed.
Preformed hoses can be produced in almost any shape and are highly durable thanks to the properties of the rubber. The flexibility of preformed hoses allows a high degree of compensation for tolerances. The rubber also prevents vibrations and saves weight and costs compared to metal, for example. Our customers use preformed hoses for fluid-tight connections, air intake hoses, turbo hoses, coolant hoses and fire-hoses, for instance. We will be delighted to put forward an attractive proposal. Contact us today for more information.
Custom-made preformed hoses in large batches
We use injection moulding to make large batches of preformed hoses. By injecting rubber into the moulds, we can make the most complex hoses quickly and in large quantities. These are often custom-made products. We make the preformed hoses precisely according to our client's specifications and application.
Preformed hoses are also available in small batches
We make small batches of preformed hoses using a mandrel. The preformed hoses are assembled manually first and then vulcanised in an autoclave. Most small batches of preformed hoses are made by our subsidiary in India in order to keep costs at a manageable level. It should be noted that we also take corporate social responsibility very seriously in our foreign subsidiaries.
Moulded parts in all types of rubber
We deliver moulded parts in all types of rubber, such as EPDM, Chloroprene, Nitrile, natural rubber, silicones, NR, Viton, etc. We have the in-house knowledge and experience to deliver moulded parts for all conceivable three-dimensional shapes. Custom production is the norm for moulded parts. Do you want us to make moulded parts for you? Please contact us for a proposal.
We produce preformed parts by means of injection moulding, compression moulding, transfer moulding or LSR moulding. We also regularly produce preformed parts that combine rubber and metal. In this case, the rubber is vulcanised to the metal when in the mould. This creates an indestructible bond between the two materials.
In the case of injection moulding, a quantity of non-vulcanised rubber is injected automatically into a mould at high pressure.
In the case of compression moulding, a pre-weighed amount of rubber is manually placed in a mould, following which the rubber is compressed to create the desired shape.
Transfer moulding is a variant of compression moulding. The process is the same as compression moulding, but the rubber is not placed directly in the mould. The rubber is pushed into the mould by a piston.
All shapes are possible
There are no limits to the shapes we can create. For example, we supply crystal-clear transparent parts, foamed moulded parts, folding bellows and protective covers. We can also supply you with moulded parts with a progressive diameter or wall thickness. It goes without saying that we deliver everything in accordance with the agreed standards and tolerances.
Extruded products are produced in a continuous process
Rubber profiles are manufactured using extrusion. The rubber is forced through a mould which gives it its shape. Recesses in the mould shape the rubber. Extruded rubber profiles are used, for example, to seal windows and doors, as an anti-slip profile and as a protective or impact-absorbing profiles. Our advisors will be happy to give you more information about extrusion products.
Most extrusion products are custom made; the possibilities for this are almost unlimited. We design a profile in cooperation with our client, after which a mould is made. The moulds are usually custom-made, exclusively for our customers. If you want, profiles are even sorted and packaged and delivered to you.
Finishing of the rubber profiles
After a rubber profile leaves the mould, it enters the vulcanisation process where the material goes from a plastic to an elastic state. We are also regularly asked to cut the profiles to length or at a specific angle. We obtain a reliable seal in the corners by gluing or vulcanising. Of course, we also carry out all the operations for you.
Our own extrusion product: Smartline
HTR has its own extrusion product called Smartline. This is a transparent rubber profile with integrated LED lighting. The Smartline product is ideal if you want to combine waterproof protection or impact absorption with signalling. Smartline is already used in buses and marinas, for example.