Bituminous coatings

Apparently a negative AP with Q < 90° can be found for particular pore geometries [53]. A different type of water repellency is desired to prevent the deterioration of blacktop roads consisting of crushed rock coated with bituminous materials. Here the problem is that water tends to spread into the stone-oil interface, detaching the aggregate from its binder [54]. No entirely satisfactory solution has been found, although various detergent-type additives have been found to help. Much more study of the problem is needed. 

Built-Up Roofing. Built-up roofing (BUR) is a continuous-membrane covering manufactured on-site from alternate layers of bitumen, bitumen-saturated or coated felts, or asphalt-impregnated glass mats and surfacings. These membranes are generally appHed with hot bitumens or cold apphed bituminous adhesives (qv). 

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... 

Organic coatings applied primarily to protect pipelines and storage tanks include paints, plastics and bituminous materials. According to Ref. 1 these can be... 

Thin coatings consist of paints and varnishes, which are applied as liquids or powdered resin with a thickness of about 0.5 mm [e.g., epoxy resin (EP) [2]]. Typical thick coatings are bituminous materials [3] and polyolefins [e.g., polyethylene (PE) [4]], thick coating resin combinations [e.g., EP tar and polyurethane (PUR) tar [2]] as well as heat-shrinkable sleeves and tape systems [5]. 

Pech, n. pitch asphalt, -art,/, kind or variety of pitch or asphalt, pechartig, a. pitchy, bituminous. Pech-bleude,/. pitchblende, -draht, m. pitched thread, shoemaker s thread, -eisenerz, n. pitchy iron ore (applied to pitticite, triplite, and a compact variety of limonite). pecheln, v.i. smell pitchy extract pitch. — v.t. extract pitch from pitch, coatjwith pitch, pechen, v.t. pitch, coat with pitch. 

Bituminous This term is used for products obtained from both petroleum and coal tar sources but the petroleum products are the more widely used. These materials are very resistant to moisture and tolerant to poor surface preparation. They are only available as black, dark brown or aluminum pigmented. The last has reasonable outdoor durability but, without the aluminum, the film will crack and craze under the influence of sunlight. Normally they cannot be over-coated with any other type of paint, because not only will harder materials used for over-coating tend to crack or craze but there is also a possibility that the bitumen will bleed through subsequent coats. The best use is as a cheap waterproofing for items buried or out of direct sunlight. 

Protection may also be obtained by insulating structures from the soil by means of protective coatings. Pipes may be dipped in bituminous compounds and wrapped with hessian, glass-fibre, or similar materials. 

Cable sheaths may be covered with paper and hessian wrappings impregnated with bituminous compounds or with extruded or taped plastics outer sheaths. At pinholes or discontinuities in protective coatings the sheath will be particularly liable to electrolytic corrosion in stray-current areas, and it is desirable to supplement this form of protection by drainage bonds or direct cathodic protection. 

For resistance to acid conditions alone, traditional filled and unfilled bituminous solutions (which have economic advantages), chlorinated rubber and shellac have been used. Crosslinking coatings, e.g. amine-cured epoxy resins, often blended with coal-tar which develops resistance to oils and solvents, have obvious advantages on chemical plant. 

The conventional bituminous or oleoresinous paints previously described are still used on the bottoms of smaller ships, the chief difference being that they are applied mainly by airless spraying. The formulations may be adjusted to permit application of thicker coats than by brush or roller, although the coats must not be too thick because oleoresinous paints require... 

Some use has been made in the water industry of loose envelopes of polyethylene sheeting and with the increasing lengths of submarine pipeline requiring heavy concrete coatings for reducing buoyancy, the use of a heavily filled bituminous coating is projected. 

These bituminous tapes are compatible with all factory-applied coatings and thus are particularly employed for weld joint wrapping in the field. 

Tapes are produced in both temperate and tropical grades and heavy duty versions can be supplied for application under hot mastic asphalts at field joints of concrete weight-coated pipelines. Wrapping of complex shapes may be achieved by first profiling with a bituminous filler compound. 

Flood Coat application of coal-tar or bituminous coatings to pipelines by flooding the heated coating materials over the pipe surface wrappings and slings are used to pull the coat underneath the pipe. 

The primary function of a coating is to act as a barrier which isolates the underlying metal from the environment, and in certain circumstances such as an impervious continuous vitreous enamel on steel, this could be regarded as thermodynamic control. However, whereas a thick bituminous coating will act in the same way as n vitreous enamel, paint coatings are normally permeable to oxygen and water and in the case of an inhibitive primer (red lead, zinc chromate) anodic control will be significant, whilst the converse applies to a zinc-rich primer that will provide cathodic control to the substrate. 

The most common dampproofing treatment for residential foundation walls is a parge coat covered with bituminous asphalt. The parge coat is used for concrete masonry walls but is not necessary for poured concrete walls. This two-stage treatment has been replaced by surface bonding cement in some areas. 

Bitumen-coated spunbonded polypropylene fabrics, 17 487 Bituminous coal, 6 703... 

Unless some external shock source was employed, it was found that molten aluminum had to reach the vessel bottom before an explosion could occur. In these cases, oiganic coatings and paints (except silicones) prevented explosions. Many coatings were studied (see, in particular, Hess et al., 1980) and, when evaluated on many tests of applicability, durability, and nonexplosive characteristics, it was recommended that epoxy, coal-tar epoxy, and bituminous paints be used. Silicone, graphite, and inorganic coatings, in general, did not prevent explosions. 

Explosive Coal consisted of thin earthenware containers of irregular shape coated with a bituminous type paint. Each piece was filled with RDX and contd an Igniter with Detonator and a small chge of BkPdr. When exposed to fire the heat eventually ignited the BkPdr chge, which in turn set off the Detonator and RDX (p 259, Fig 196)... 

Gas, Coat Mine or Firedamp. A mixture of methane (CH4) and air, usually present in "gaseous (fiery) coal mines", such as soft (bituminous) coal mines... 

The Shell papents broadly cover a bituminous paving composition in which the aggregate is coated with bituminous binder and the excess undissolved sulfur acts as a filler in the void spaces between the aggregate. The process is particularly adaptable for use with inexpensive, ungraded sands which are not suitable for use as an aggregate in a conventional hot mix asphalt concrete this mix class has often been called sulfur-asphalt-sand (SAS), but Shell s product is currently tradenamed THERMOPAVE. 

In tests (Ref 30) to determine the effect of liners and coating on the sensitivity of 50/50 Pentolite charges contained in bombs it was concluded that very little effect was obtained with a wax coating on the inner surface of the bomb, but an asphalt dip reduced the detonations considerably. The tests conducted were rather limited in the variety of waxes tested. Subsequent tests in 100-lb bombs were somewhat inconsistentwith the initial finding. Seven hundred-fifty lb general purpose bombs loaded in the 1970 s did use both a nose pad and liner of a bituminous material... 

Semibituminous Coat. Coal that ranks between bituminous coal and semianthracile. It is harder and more brittle than bituminous coal, has a high fuel ratio and bums without smoke. Semibituminous coal is also known as metabituminous coal which is defined as containing 89-91.2% carbon, analyzed on a dry. ash-free basis. The term smokeless coal also is used. 

Bituminous Coat. Coal that ranks between sub-bituminous coal and semibituminous coal and that contains 15-20% volatile matter. It is dark brown-to-black in color and bums with a smoky flame. Bituminous coal is the most abundant rank of coal and is commonly Carboniferous in age. The most common synonym is soft coal. 

Lignite Coal. A brownish-black coal that is intermediate in coalihcalion between peat and sub-bituminous coal consolidated coal with a calorific value less than 8,300 Btu per pound (4615 Calories/kg), on a moist, mincial-matter-free basis. Synonyms include brown lignite and brown coat. Further classifications of lignite are made on the basis of calorific value ... 

In the process of Dietzsch Co, a continuous roll of pulp, in the form of a sheet 45cm wide, was passed thru a chamber, countercurrently to the nitric acid fumes and then thru a bath contg coned nitric acid. After washing the resulting NC with water and air-drying, the sheet was coated on one side with an adhesive(such as Vinarol) and made into a cartridge case. It was waterproofed by coating it with a bituminous lacquer mixed with an acetonic soln of NC(Ref 2,pp 7-11)... 

---