A viscous elastic coating is based upon a material that shows both elasticity (stretch) and viscous (flowable) behavior. The material will show some viscous cold flow, and has adhesive properties based upon van der Waals interaction with the surface. Due to the viscous component of the material, a complete wetting of the surface takes place. When for instance overlap takes place during application, the layers of the product will flow to become one continuous coating. The elasticity of the product ensures a layer thickness, peel strength and resilience against movements.
For maintenance and in the ditch applications, an easy to apply coating is of utmost importance. Unlike for instance tapes, a continuous homologue layer of coating is favorable to prevent spiral effects. Most importantly the adhesion of a viscous elastic coating is created on molecular level, such that water cannot penetrate in between coating and surface. Salts have impact on spray applied coatings, where viscous elastic coatings are not adversely influenced in their performance by salts. They encapsulate any residue due to the viscous component of the material. Therefore the viscous elastic coating outperforms conventional coatings in the field.
VISCOTAQ is a true viscous elastic material. It does not use any butyl or rubber type components but is amorphous. Furthermore VISCOTAQ is a solid material, therefore stable, once applied. Other viscous elastic systems are fluid type materials and therefore are continuously in a dynamic phase. Especially under elevated temperatures and/or under an angle at soil to air transitions, this system may show some sliding, where VISCOTAQ does not. Reason is that VISCOTAQ is a solid with a melting point at 152,9 C and a true yield point at elevated temperature.
The elastic component creates a memory effect during damage while the viscous component create some flowing properties. Let’s say somebody punctures the coating. The outerwrap has some tension around the product and enough to create some flow: the material oozes out of the pinhole and the repair is automatically made.
We have tested VISCOTAQ with different grades of surface preparation and as a rule one can say that the higher the grade of surface preparation the better the adhesion of a material will be. With VISCOTAQ surface preparation is less sensitive and one can say the everything above a commercial brush preparation is sufficient for a proper performance of the coating. Our advise however is to always clean as from a level SA 2-1/2 or NACE SSPC 10. This always gives the best performance.
You can use VISCOTAQ as a repair material for pipeline coatings however the material is not suitable for remediation of pipelines i.e. repair of wall thickness. VISCOTAQ can withstand low pressure leaks in pipe but for higher pressures we advise to use composite materials or welded steel sleeves.
No, also not at elevated temperatures. This is one of the unique properties of VISCOTAQ visco-elastic coatings. Unlike other viscous elastic materials, VISCOTAQ is formulated to have a uniform layer thickness around the pipe under normal circumstances. This is the advantage of a solid material and a true yield point.
Yes you can although it depends very much upon the situation in and near the pipeline trench(es) if this will help you to improve the speed of operation. In case of bell holes one may consider to wrap by hand as one may have several teams wrapping at the same time in different bell holes. With a wrapping machine one needs to change rolls and one needs to move the machine from one bell hole to another and these actions also require time.In case of a continuous in one trench a wrapping machine might be advantageous although we think one should consider this only for longer distances.
Yes you can. VISCOWRAP is a solid and has a Heavy Duty PE as an Outer Wrap and hence a very high mechanical impact. The best way is to lift the pipe by hooks at both ends and consequently lower it into the trench. In this way you avoid coating damage as much as possible. In case of long distance transportation VISCOTAQ Rockshield Protection is available for protection the coating.
Yes absolutely ! Although VISCOTAQ products can be considered as a solid at the end, the material has a cold flow and wetting characteristics and will penetrate the pores of the substrate. The bond of VISCOTAQ material increases over the time. VISCOTAQ will always show a cohesive fracture, which means that when the material is peeled off the material will break apart and leave a corrosion protective layer on the pipe. In this way one has always the guarantee of corrosion prevention which makes VISCOTAQ so unique.
Every batch of VISCOTAQ material has a batch number indicating among others (but not limited to) the date of production, the machine where it has been produced on, the raw components that have been used et cetera. The material made of each batch is turned into a final product which is packed in heavy duty triple wall carton boxes. All cartons are packed on pallets with side stacks and sealed into seaworthy pallets. Pallets can be stacked in a 20’or 40’container. Of each roll shipped the date of production and production details can be retrieved.
Yes. VISCOTAQ is an joint invention of Kleiss & co and Amcorr Products and Services and patents have been applied for worldwide. VISCOTAQ can be considered as an improved visco elastic coating technology. The goal has been to develop a visco elastic coating with improved coating characteristics. VISCOTAQ for instance is a solid material designed as a pressure sensitive adhesive. As a solid it will not show any dripping behavior at elevated temperatures and cause unequal coating thicknesses. Moreover due to its solid characteristics the material will show a good resistance against shear. When tested against shear (Alyeska Shear Test January 2010) the material showed no shear at 23 C and the shear at 50 C stopped after 50 hours and was minimum. Even at an elevated temperature of 80 C the shear was only 5 mm/hour and a cohesive fracture was witnessed leaving material on the pipeline for corrosion prevention.
Yes, but this depends on the ambient temperature and the type of VISCOTAQ material. The higher the temperature the quicker the tack. As a solid the adhesion process is different from a typical fluid but at the end the adhesion of VISCOTAQ is tremendous and unrivaled due to the design of the material – which can be explained by specific rheological models – and due to the low surface tension. Actually this is one of key points of the invention and the patent .
You can expect a cohesive fracture. And a cohesive fracture is a cohesive fracture: when peeling off the material breaks apart and a layer is left on the pipe. Officially a peel test should be done after 7 days according to the EN 12068. In case this is not possible we advise you to wait 72 hours before doing such test as VISCOTAQ needs a certain time to completely adhere to the substrate. Once adhesion is obtained it is impossible to peel VISCOTAQ product off the substrate !
Never say never….There may always be unforeseen circumstances like earthquakes, unknown or unforeseen chemicals in the ground, earth slides, natural disasters et cetera that can cause a change in the underground conditions and of course nothings lasts forever. But to answer the question : No, you will not get any corrosion within a reasonable time span.
It means that once applied the VISCOTAQ viscous elastic coating system will not show any chance in performance as we are facing an inert, continuous water impermeable and stable system. It means that after 30 or 40 years the corrosion preventive characteristics are the same. The material does not deteriorate and will not crack, becomes brittle or show more moisture or gas permeability in the course of time. So it is a guarantee for the performance of the coating.
It does not mean that corrosion can never happen as there may be unforeseen circumstances that occur later like earthquakes, landslides, unknown or unforeseen chemicals in the soil et cetera. The warranty guarantees that if the coating performance decreases new coating material will be supplied free of charge. The coating however should have been applied according to VISCOTAQ’s instructions. Examples of these requirements are for instance a surface preparation according to the manufacturer’s instructions, trained and certified applicants, continuous inspection and testing of the application by a certified VISCOTAQ INSPECTOR. For more details about the 40 years warranty please contact Edwin Welles on [email protected] or Leo van Beugen at [email protected]