Asphalt sheet

Hot asphalt applications had been used for many years in concrete tanks, inner lined with brick for similar service, and also, of course, unlined wood tanks made from timber, and small pickling tanks made by hollowing out cavities in granite blocks. But the use of hot asphalt as a liner for steel tanks had been unsatisfactory due to the erratic cold flow of the asphalt which demonstrated selective adhesion to steel and so would tear and open cracks in the membrane system in the areas of cold flow below the points where it adhered. To overcome this difficulty, a number of inventive persons experimented with the manufacture of asphalt sheet lining materials, similar in form to the sheets of natural rubber, in which the asphalt was compounded with various admixtures, including rubber. These asphaltic compound sheets were then warmed sufficiently to make... 

Just as in the manufacture of sheet natural rubber and the asphaltic sheet linings, the basic material as the sheet lining manufacturer receives it from the plantation (rubber) or from the refiner or importer (asphalt), the manufacturer of the synthetic lining materials will receive his synthetic elastomer, thermoplastic or other basic resin from the company that produces it-and will have to blend it with fillers, stabilizers, plasticizers, and other materials to make a suitable compound which will-as a lining—perform its function satisfactorily under the anticipated conditions, and for an economical length of time. The actual amount of the basic resinous material in the compound may be as low as 70% of the total weight. 

The other major class of nonporphyrin metals is the complexes of the tetradentates of mixed ligands. These ligands can be any combination of four atoms from N, S, and 0. They can be small, the (aa) class, or large, the (ab) class. The former class is formed from polar resin molecules and the latter is formed from asphaltic sheets. The ligand sites could be as follows ... 

Decopperized blast furnace bulHon is softened to reduce impurities below 2% before casting as anodes. The electrolyte is a solution of lead fluosUicate [25808-74-6] PhSiF, and free fluosUicic acid [16961 -83-4]. Cathode starting sheets are made from pure electrolytic lead. The concrete electrolytic ceUs are lined with asphalt or a plastic material such as polyethylene. 

Asphalt-coated glass fiber venting base sheet with fine mineral surfacing on the top side and coarse granules on the bottom side perforated/embossed or not. The coarse granules provide an open, porous channel in the horizontal plane (5,11). 

Standard Test Methods for Asphalt RoU Roofing, Cap Sheets, and Shingles... 

Sheet form, composed of organic roofing felt, saturated with asphalt and coating on both sides with asphalt compound that may or may not contain mineral stabiHzer, surfaced with powdered talc, mica, or other tine mineral matter to prevent sticking. Classified, in mineral net mass per unit area of roofing, as Type I, 1943 g/m (39.8 lb/100 fC) Type II, 2666 g/m (54.6 lb/100 fC) Type III, 2495 g/m (51.1 lb/100 fC) and Type IV, 1943 g/m (39.8 Ib/lOOfC). 

Sheet form, in widths as agreed upon by purchaser and seUer, composed of asphalt-saturated organic felt coated on both sides with asphalt and surfaced on weather side with mineral granules, except for selvage. Classified, in minimum net mass of granule-surfaced portion, as Type I, 3610 gm/m (74.0 lb/100 fC) and Type II, 3490 gm/m (71.5 lb/100 fC). 

Sheet form, 914 mm (36 in.) in width, or widths agreed upon by purchaser and suppHer, composed of asphalt-saturated organic felt with approximately half the width of weather side coated with asphalt and surfaced with mineral granules, for use as cap sheet in constmction of BUR. Materials covered by this specification, in minimum mass per unit area, are Type I, 1806 g/m (37.0 lb/100 fU) Type II, 2260 g/m (46.3 lb/100 fU) Type III, 1733 g/m (35.5 lb/100 fU) and Type IV, 2090 g/m (42.8 lb/100 fU). 

ASTM D2626, Asphalt-Saturated-and-Coated Organic Felt Base Sheet Used in Roofing, ASTM, Philadelphia, Pa. 

Waterproof. Waterproofing barrier systems may be either hot- or cold-appHed. The hot-appHed generaUy involve a bituminous material such as asphalt used in conjunction with a reinforcing fabric such as roofing felt, cotton, or glass cloth. Cold-appHed can be bituminous or elastomeric materials either in Hquid or sheet form, with or without fabric reinforcement. Liquid elastomeric treatments include neoprene, polyurethanes, and blends of these or epoxies with bituminous materials. Among the commonly used precured elastomeric sheet materials are neoprene, polyisobutylene, EPDM mbber, and plasticized PVC. Polyethylene and PVC films and nonwoven plastic or glass fabric coated with bituminous materials also find use (78). Because these... 

Typical apphcation of a BUR would be to mop or apply asphalt to a substrate to approximately 1.1 kg/m (23 lbs/100 ft ), or the thickness of a dime. A ply sheet would then be unroUed into the hot asphalt. Additional ply are then mopped in, with each layer offset so that the roof has three or four phes of felt over the entire roof. The amount of offset is calculated by the formula, offset = 34 in. (86.4 cm) /number of pHes. Manufacturers of pHes print laying lines on the felts at the correct locations to assist in laying up the roof with the correct offset. 

Organic ply sheets are manufactured from 3 ft (91 cm) wide organic felts, saturated with soft asphalt, that cover 400 ft (37 m ). Laying lines are apphed to the top side of the ply sheets, and the felts are perforated about 2 to 4 in. (5 to 10 cm) on center to permit the gases to escape during the roof constmction process. 

SBS membrane systems are generally installed in hot asphalt but can be installed using a torch like APP products or in some cold apphcation cement systems. Like APP systems, they are generally installed in multiple layers. The undedayment layers are generally standard BUR felts or basesheets. SBS membrane sheets can also be formulated to be self-adhering. These products are no longer used in membrane appHcations but are used as ice and water dam matedals on the eaves under shingle roofs in cold climates. 

Both fiber-glass mats and polyester mats are used either individually or combined in SBS membrane sheets. Because of the elastomedc properties of the asphalt, SBS sheets have developed a reputation as being very tough and abuse-resistant. However, they do not have any better ultraviolet resistance than conventional asphalts, so most of the SBS sheets come with a factory-appHed surfacing of granules. 

The finish may be a coating (paint, asphaltic, resinous, or polymeric), a membrane (coated fmt or paper, metal foil, or laminate of plastic, paper, foil or coatings), or sheet material (fabric, metal, or plastic). 

Membranes are applied directly to the metal or concrete surface to protect from corrosion by any liquor that penetrates the brick lining through pores and cracks. Membranes consist of sheet material bonded to the metal or concrete, e.g., flexible PVC sheet, or it may be formed in situ (e.g., polyester resin reinforced with glass fiber, or synthetic rubber sheet, lead, polyisobutylene, polyethylene and asphalt). 

Two possible forms of membrane are hot applied mastic asphalt or bitumen/butyl rubber sheeting with welded or glued joints. The membrane under the floor slabs has to be lapped with that around the walls. It is essential that the membrane is protected during construction, and a typical arrangement is as shown in Figure 6.15. 

Sheet metal Cast, new Galvanized Asphalt-coated Ducts... 

Roofing installation or repair using hot-mopped asphalt or using open-flame heating devices to seal roofing sheet membrane seams... 

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