Epoxy coated rolls

Epoxy coated rolls (450-500 inVkW) offer a more durable covering than silicone or Hypalon and are also a logical choice for basic corona treating applications. Epoxy coatings have harder surfaces than silicones or rubbers and offer added insurance against unexpected roll failure from exposure to excessive corona discharges, heat build-up, or accidental operator-inflicted damage from an operator s knife. A pinhole in an epoxy roll can usually be repaired on the production site. Life expectancy of an epoxy covered roll is approximately one year. 

Figure 3.25 Epoxy-coated section of a tube sheet and rolled tube.

Degradation of Amine-Cured Epoxy Coating on Cold-Rolled Steel... 

FTIR-RA spectra of the amine-cured epoxy coating on cold-rolled steel before and after exposure at 40°C and 80% RH are shown In... 

T. Nguyen and E. Byrd, FTIR-RA spectral characteristics of epoxy coatings on cold-rolled steel effects of film thickness and angle of Incidence, Appl. Spectrosc. submit for publication, 1985. 

Corrosion Protection. Although steel underground transmission lines are often protected by coal tar or fusion bonded epoxy coatings, a large volume of polyethylene tapes as well as some vinyl-backed tapes are used for corrosion protection. Pipes of large diameter, such as oil line pipes, are usually machine-wrapped in the field just prior to placement in the ground. The tapes are unusual in that the backing is from 12 to 15 mils thick and the butyl-based adhesive is approximately of the same thickness. For the pipeline industry the rolls are 18 in. wide and contain up to 800 feet of tape. There is a reduction currently in domestic pipeline construction but appreciable amounts of pipewrap are exported. 

Comparing universal roll system performance to systems utilizing Hypalon , silicone, and epoxy covered rolls, the higher efficiency ceramic coating requires less power to achieve the same surface tension results, therefore reducing the cost of the power supply required. 

Although rolling and dipping are sometimes used, power spray painting is the usual method of paint application. Among the coatings used are polyurethane, epoxy, acrylic, alkyd and vinyl based paints. With paints that are oven cured, products must have sufficient heat resistance to survive without distortion, etc. 

To ensure that a liquid metal is completely disintegrated into droplets before the initiation of any solidification in the gap, the heat transfer between the liquid metal and the rolls must be minimized. Materials with low thermal conductivity and poor wetting properties have been found to have the most significant effect on reducing the heat transfer. Epoxy and phenolic resin coatings have been applied to... 

The paints were spray applied to a number of substrates. Two coatings gave a final dry film thickness between 85 to 130 microns. For ac impedance studies the coatings were applied to shot (steel) blasted cold rolled steel plates. For interface metal-loss studies by electrical resistance the coatings were applied to 10 micron Fe foils (99.85 purity), adhesively attached by Araldite 2003 epoxy paste on one side to grit blasted glass plates. 

Fourier transform Infrared spectroscopy has been shown to be an excellent tool for surface and Interface studies (.2), In this paper, the application of reflection/absorption Fourier transform Infrared spectroscopy (FTIR-RA) for studying the degradation of amine-cured epoxy and polybutadiene coatings on cold-rolled steel after exposure to a warm, humid environment is reported. 

A primer adhesive is first applied to a properly prepared concrete surface. A thin coat of epoxy mortar is then applied with a trowel. While this thin coat is still wet, a fiberglass membrane is rolled into the mortar. The edges of the membrane should be overlapped 2 inches. The mortar will squeeze up through the voids in the fiberglass mesh, resulting in adhesive base to which the final epoxy mortar will adhere. While this first application of mortar is still tacky, the second layer of epoxy mortar is applied over the glass cloth. This second layer may then be screeded and leveled. ... 

The chemically resistant coatings, such as the baked phenolics, baked epoxies, and the air-dry epoxy, vinyl, and neoprene coatings, are ideal for minimizing contamination of chanicals handled in steel equipment. They should not be used where 100% protection from corrosion is required. An excellent material for immersion service has been developed that consists of flakes of glass dispersed in a polyester resin. This is applied by spray to a properly prepared surface, and the wet coating is rolled with a paint roller to orient the glass flakes in a plane parallel to the substrate and to provide maximum resistance to chemical attack. 

The planar reinforcement was coated and cured in a continuous production process as depicted in Fig. 5. The fabric was driven through a mold filled with epoxy resin. Excessive resin was squeezed out between rollers, so that a uniform application of the resin as well as a nearly saturated roving was achieved. Immediately after coating, the textile was cured in a heating tower at a maximum temperature of 160°C and coiled up to a roll. 

Cold rolled steel This material is intended for hght duty finer applications only. However, carefully prepared and treated to resist corrosion, by a coating of epoxy, this is the most common... 

Wang, Y, and X. Jing. 2004. Preparation of an epoxy/polyaniline composite coating and its passivation effect on cold rolled steel. Polym J Tokyo Jpn 36 (5) 374. 

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