Cutback

The standard NF T 65-002 defines five grades of cutbacks according to their pseudo-viscosities. 

Road paving. This includes bitumen, cutbacks and fluxed bitumen as well as emulsions. Each of these products is subject to very special application techniques. This list is completed by the use of poured asphalt, even though this product is better suited to smaller surfaces sidewalks, courts, etc., than to pavements. Since the middle of the 1980 s, air-blown bitumen is no longer used for road construction. 

Flash point (cutbacks, fluxed bitumen). Standards NF T 66-009 and IP 113... 

There are no specifications, but there are two French standards grouping the characteristics of bitumen and cutbacks. 

Distillation of cutbacks and fluxed bituminous products NF T 66-003 ASTM D 402 Distillation... 

Customblen Cut-and-paste plot plans Cutback asphalt Cutback asphalts Cuticle removers Cutin... 

North American HF production capacity has declined since the early 1980s and several smaller producers, such as Harshaw and Essex, have closed plants. Production is expected to continue to decline in the short term because of chlorofluorocarbon (CPC) cutbacks, but is expected to rebound later in the 1990s as replacement hydrochlorofluorocarbons are introduced to the marketplace. 

The main uses of petroleum naphtha fall into the general areas of solvents (diluents) for paints, etc, dry-cleaning solvents, solvents for cutback asphalt, solvents in mbber industry, and solvents for industrial extraction processes. Turpentine, the older, more conventional solvent for paints, has been almost completely replaced by the cheaper and more abundant petroleum naphtha. 

Road oils are Hquid asphalt materials iatended for easy appHcation to earth roads. They provide a strong base or a hard surface and maintain a satisfactory passage for light traffic. Liquid road oils, cutbacks, and emulsions are of recent date, but the use of asphaltic soHds for paving goes back to the European practices of the early 1800s. 

Cutback asphalts are mixtures ia which hard asphalt has beea diluted with a lighter oil to permit appHcatioa as a Hquid without drastic heatiag. They are classified as rapid, medium, and slow cuting, depending on the volatiHty of the diluent, which governs the rates of evaporation and consequent hardeniag. 

Cold Applied Coatings/Adhesives. Cold appUed BUR appHcations do not require heating to fluidize the bitumen on the job. Simple appHcation and economical maintenance ate primary considerations. Bitumens are Hquefied by dissolving in a solvent (cutbacks) or dispersing in water... 

The hquid cutback asphalts are prepared in a number of viscosity grades, ranging generally from 70 to 6000. The grade number indicates the viscosity at 60°C. 

Preparation is accompHshed by simple blending of the diluent into the hot base asphalt. This is generally accompHshed in tanks equipped with coils for air agitation or with a mechanical stirrer or a vortex mixer. Line blending in a batch circulation system or in a continuous fashion (40) is used where the volume produced justifies the extra faciUties. A continuous, line-blending system is appHcable to the manufacture of cutback asphalts and asphalt cements (Fig. 8). 

Fig. 12. A viscosity-temperature chart, mm /s = cSt ----, iadustrial asphalts ---cutback asphalts ...

Distillation (ASTMD402). Approximate amounts of volatile constituents are deterrnined by this test which is particulady appHcable to cutback asphalt and road oils. 

Flash Point (ASTMD92). The Cleveland open cup method is most commonly used although the Tag open cup (ASTM D3143) is apphcable to cutbacks. Flash point is an indication of fire hazard and the test is frequendy used to indicate whether a given product has been contaminated with materials of lower dash point. 

Liquid Asphalt. Liquid asphalt products comprise cutback asphalts and emulsions. A number of grades of different viscosities are available, which permit appHcation from ambient temperatures to 150°C. The lower viscosity products are used for dust-laying purposes and as tack coats, prior to laying asphalt surface courses. The heavier grades are used for mix-in-place road mixes. 

The principal use of coal tar ia paviag is as a seal coat to bitumea paviag. Asphalt for paviag comes ia several forms deteroiiaed by the iateaded appHcatioa, ie, straight asphalts called asphalt cements (AC), asphalt emulsioas, cutback asphalts, and road oils. 

L If a nuclear power plant loses its connection to the offsite load, it must shutdown because it cannot be cutback sufficiently that its electrical output matches its "hotel" load. Outline a PSA study to determine the risk reduction that might be achieved by switching in a dummy load to avoid shutdown and keep the plant online. 

Efficiency combines the resource and effectiveness dimensions. In fact, the criterion has many different (and non-contradictory) definitions, depending on the context. For the purposes of the present discussion the pursuit of efficiency can be taken as either reducing the cost of achieving a given level of effectiveness, or improving the effectiveness achieved from a fixed budget or set of resources. Efficiency has sometimes been seen as a controversial criterion, but much of this controversy probably stems from the tendency of some policy-makers to use the term efficiency when they really mean cheap , and to refer to efficiency improvements when they really mean cutbacks . Understood and employed properly, the criterion really ought to be widely accepted, particularly when used in combination with equity. 

Fig. 3.34 LDA of the microarray signal patterns obtained in practical KAMINA tests to detect gaseous precursors of smoldering fires through overheated cable insulation. Prior to the LDA the measured resistances of the sensor segments were normalized to the median of all sensor segments and the number of variables was reduced by a Principal Component Analysis (PCA) to cutback the noise. Clear distinction is achieved between clean air...

Optical losses in the liquid-filled ARROWs are typically measured using the cutback method. This measurement technique assumes optical transmission in the waveguide can be described according to... 

---