Bonded sheet lining fabrication

Solid sheet linings can also be applied either as an adhesive-bonded lining or a loose-fitting lining. Adhesive-bonded sheet linings on steel substrates consist of fabric backed sheets bonded to steel vessel walls with neoprene or epoxy based adhesive. Linings may be applied in the field or in the shop. Joints are heat welded using a rod of the same polymer as the sheets. 

Polypropylene sheet appeared in the 1950s, first as a plain white sheet, then, like the early PVC sheet, with a fabric backing laminated to it. No effective bonding agent was ever found for this material, and this author has not heard of its use in this manner for a number of years. However, there is available a sheet lining material having a sheet of polypropylene laminated to a sheet of natural or synthetic rubber to provide an adhesive accepting surface. 

Dual laminate structures are composed of fiber reinforced plastic (FRP) built with fiuoropolymer sheeting that serves as a lining. This lining is fabricated by machine and hand welding of fiber backed fiuoropolymer sheets, like those described above for adhesive bonded systems. The fabric aids in bonding the sheeting to the FRP. 

Fluoropolymer linings are installed using adhesive bonded fabric-backed sheets, sprayed dispersions, rotolining, electrostatic sprayed powders and by mechanically attaching loose sheet linings. 

The principle of dual laminate construction is to line an FRP vessel or column with a fluoropolymer lining. However, the sequence of construction is to first make the liner out of fabric-backed sheets the same as in the adhesively bonded construction. The FRP structure is then laminated on the liner to pro-... 

Tape and film adhesives are terms used loosely and interchangeably for adhesives in sheet form. More correctly, tapes are supported on a web of paper or nonwoven fabric or on an open-weave scrim of cotton or nylon. Snpporting fibers are useful in that they provide a positive stop under bonding pressure. This can be nsed to control bond line thickness and often to help distribute stresses. Films on the other hand, are free of reinforcing fibers and consist only of the adhesive in thin, sheet form. 

Roof linings constitute a special case, with unique problems. The widely used basic design of a preformed sheet of resinated cardboard, bonded over the complete surface, is not really adequate for today s customers or today s production techniques. The trends are towards easier installation and a more luxurious, softer surface. Hence foam-backed knitted fabrics of various kinds are increasingly used, although there is still a significant market for expanded PVC. A newer low-cost solution is a moulding composition comprising textile fibre fleece bound with phenolic resin. 

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