Although URM has a big range of normal “sulphur’-cured EPDM Hoses, the demands for EPDM peroxide-cured hoses are increasing continually.
The main benefits of EPDM peroxide-cured hoses over their sulphur-cured brethren are:
Meets or exceeds SAE-J20 Class D-3, meets the requirements of SAE J1684 (electro-chemical resistance), improved chemical resistance (including resistance to organic-acid-based / OAT coolants), higher temperature resistance upto 150 degrees Celsius (300 F), enhanced Modulus and Compression set and less tendency to blooming.
These convoluted / corrugated hoses are reinforced with multiple layers of fabric, + 1 ply of Stainless-Steel wire. They form an ideal solution for fitments where there is a lot of mis-alignment between mating parts (or heavy flexing/3-axial movement). Form a higher bend radius compared to normal corrugated as well as higher pressure resistance compared to regular straight hoses. Available in a range of materials including Silicone, EPDM, NBR, PVC-NBR, CR, etc.
Wrapped Rubber and Silicone Hoses: Relatively higher working pressure of upto 15 bar (depending on diameter) can be achieved.
Higher Pressures can be achieved by increasing:The amount of of Fabric layers. Changing the “type” of Fabric (including addition of SS-wire ply). Hoses can also be reinforced with stainless-steel wire for additional Pressure (or Vacuum Pressure) resistance. Vacuum (negative) Pressure of Extruded and Wrapped Hoses can also be enhanced, by inserting a stainless-steel spiral coil on the inside of the hose.
Different Metal-Parts (with ‘threading’ if needed) as per customer’s design can be fitted in the hose during production, in Stainless-Steel, Brass, or other alloys.
Silicone Hoses/Couplers Reinforced with Fiberglass fabruc commonly used for connections between Turbocharger and Engine, where there is less Vibration, or negligible misalignment at the fitment.
Working Temperature: – 54 to + 260 degrees C (-65 to + 500 degrees F).
The Hoses resist the usual conditions (coolants, ozone, oil-traces, etc) found in the engine bay.
A hose can be made to look good outer surface with the help of hot-air curing. However, it is equally important to (a) use the correct materials, (b) post-cure the hoses, and (c) maintain a clean atmosphere so that particles do not enter the cross-section of the hoses.
Unfortunately, a lot of manufacturers do not follow the recommended processes by adding certain additives in the silicone/fluorosilicone rubber, which is not ideal.
Testing has proved to us, that sometimes, the textured/classic finish hoses perform better. This is because of the curing process used; i.e. steam-pressure cure instead of hot-air curing. With the steam-cure, it is possible to achieve higher levels of ply-adhesion, pressure-resistance, and other physical properties.
We have achieved the best of both worlds. With our specially formulated materials (with state-of-the-art contemporary German peroxides), we have managed to retain the hot-air cure, & at the same time get excellent properties.
However, the next time you get a classic/textured finish hose on your table, do not discount it. It might just be the one to achieve your specs!
Spiral-wound Hoses are wrapped using narrow strips of Calendared fabric, rather than big sheets; resulting in increased robustness, high pressure resistance, and improved performance under contact with various ‘harsh’ coolants
Increased robustness due to “more fabric per hoses. Spiral-wound option is available with all the polymers (VMQ, FKM, EPDM, NBR, PVC-NBR, CR, SBR, AEM, ACM, etc) and all fabrics (Polyester, Meta-aramid, etc). Additionally, SS wire reinforcement can also be included for added pressure (positive or negative) resistance.
URM offers a range of High-Temperature Silicone Hoses lined with Viton (R) or FKM, for resistance to oil, diesel, petrol, chemicals and other fluids which are not compatible with Silicone and Fluorosilicone.
Although the Low-Temperature resistance of FKM is not as good as VMQ/FVMQ, it is still preferred because of better high-temperature resistance and it’s superior permeation properties and (c) better abrasion resistance.
However, although we offer our Silicone Hoses generally in the “smooth and shiny” wiped finish, the hoses lined with Viton/FKM are offered by us in a Textured finish.
This is due to the process limitations in order to get a very strong “cohesive” bond between the Silicone and the inner FKM liner.
Universal Rubber offers hoses that exceed most of the global standards for the adhesion strength between Silicone and FKM.
In the above picture, you can see the generic Silicone Hoses offered by us (smooth and shiny) on the left side.
On the right side is the “textured” hoses with the inner Viton (R)/FKM liner.
These hoses are available in multi-fabric-layer option for higher pressure resistance. Also available with SS wire reinforcement between the plies for high vacuum pressure resistance.
SAE J20 R4 Class D1/D2: Typical Temperature range -40 to +125 degrees celsius; These Hoses are made in sulphur-cured EPDM and are usually reinforced with Polyester yarn. Upon specific customer demand, they are reinforced with Aramid Yarn.
SAE J20 R4 Class D3: Typical Temperature range -40 to +150 degrees celsius; These Hoses are made in peroxide-cured EPDM and are usually reinforced with Aramid yarn.
At the moment the industry prefers silicone hoses as to deal with high temperatures and pressures under the new Euro VI regime. But silicone does have some minor drawbacks. It is non resistant to acidic or alkaline environments (even with lined with Fluorosilicone) and incompatible with Sodium or Potassium-ethylhexanoate.
To deal with these drawbacks, URM has launched a new type of hose with a specially formulated inner-layer to withstand against permeation of these extremely harsh OAT coolants and their fumes.
The new hoses are available in a textured finish (not smooth/shiny finish). All RAL colours are available; however the inner lining will always be Black.