Special-purpose type

The coarse, nonpigmentary cmdes are particle si2e reduced by a variety of processes to obtain pigmentary CPC. Since CPCs are utili2ed in a variety of industries and a host of appHcations, the specific property requirements vary widely. A large number of special-purpose types are commercially available designed to provide optimal properties for specific appHcations. 

Special-purpose type Booths of this type are specially designed, in shape and function, for a certain production facility and/or process. 

In view of the fact that phthalocyanine blue pigments are utilized in a host of applications, the requirements for their use vary considerably. A large number of special-purpose types are therefore supplied which are custom designed to exhibit optimized properties in certain media to suit particular demands. 

Copper Phthalocyanine grades are also supplied as special-purpose types with a limited or defined free copper content, targeted for the coloration of rubber (see p. 444). 

Aircraft bombs were introduced in World War I, and soon, various special purpose types were developed. Therefore, a color code was developed. Again each service (land and sea) of the major powers developed their own identification system consisting of colored bodies, colored bands, metal stampings and ink stencil markings... 

Specifically the Directive prohibits the marketing of general purpose alkaline-manganese batteries containing more than 0.025% mercury (0.05% for special purpose types). Furthermore it calls for the marking and separate collection for recovery or... 

Synthetic rubbers are classified broadly into general-purpose types and special-purpose types. As their name implies, the general-purpose types are intended for applications such as the manufacture of tyres and general mechanical products which call for no properties other than satisfactory elastomeric... 

Other styles of leaf chain are available from some manufacturers. These chains are special and do not conform to any industry or American National Standards. Examples of these types are wrench chains and laminated block chains. One feature of wrench chain is the extended pins that are used to clamp the chain in position. Some types of laminated block chains have openings that allow the chain to be used with a toothed device similar to a sprocket. These and aU other special types of chains can be found in manufacturers catalogs. Pictures of the two special-purpose types of leaf chain mentioned can be found in Figure 8-11. 

FIGURE 8-11 Two special-purpose types of leaf chain. 

Special purpose and blended Portland cements are manufactured essentially by the same processes as ordinary Portland cements but have specific compositional and process differences. White cements are made from raw materials of very low iron content. This type is often difficult to bum because almost the entire Hquid phase must be furnished by calcium aluminates. As a consequence of the generally lower total Hquid-phase content, high burning-zone temperatures may be necessary. Past cooling and occasionally oil sprays are needed to maintain both quaHty and color. 

Sr. no. Speciftcatiotis Measuring CTs Protection CTs Special-purpose protection CTs type PS ... 

Textile motors Crane motors Determining the size of motor Sugar centrifuge motors Motors for deep-well pumps Motors for agricultural application Surface-cooled motors Torque motors or actuator motors Vibration and noise level Service factors Motors for hazardous locations Specification of motors for Zone 0 locations Specification of motors for Zone I locations Motors for Zone 2 locations Motors for mines, collieries and quarries Intrinsically safe circuits, type Ex. f Testing and certifying authorities Additional requirements for ciritical installations Motors for thermal power station auxiliaries Selection of a special-purpose motor... 

The dry helical lobe rotary compressors nonlubricated cylinder types of compressors are used for injecting of the fuel in gas turbines at the high pressure needed. The gas turbine application requires that the compressor be dry. This standard is primarily intended for compressors that are in special purpose application and covers the minimum requirements for dry helical lobe rotary compressors used for vacuum, pressure, or both in petroleum, chemical, and gas industry services. This edition also includes a new inspector s checklist and new schematics for general purpose and typical oil systems. 

API again offers some help. API 671 covers the special purpose coupling as either a specification or guideline. It has been common practice for the compressor vendor to furnish the couplings. Most compressor vendors have no problem accepting this responsibility, while driver vendors sometimes prefer not to furnish them. In some compressor types, the coupling style will be somewhat influenced by the user. When torsionals become a major consideration, the vendor may have to make the choice based on system need. In all cases, the user should establish his right of approval if the vendor performs the selection. 

As the author pointed out in the first edition of this book, the likelihood of discovering new important general purpose materials was remote but special purpose materials could be expected to continue to be introduced. To date this prediction has proved correct and the 1960s saw the introduction of the polysulphones, the PPO-type materials, aromatic polyesters and polyamides, the ionomers and so on. In the 1970s the new plastics were even more specialised in their uses. On the other hand in the related fields of rubbers and fibres important new materials appeared, such as the aramid fibres and the various thermoplastic rubbers. Indeed the division between rubbers and plastics became more difficult to draw, with rubbery materials being handled on standard thermoplastics-processing equipment. 

There are two categories of equipment which determine the selection of equipment general-purpose and special-to-type equipment. It should not be necessary to specify all the general-purpose equipment needed to perform basic measurements, which would be expected to be known by appropriately trained personnel. You should not need to tell an inspector or tester which micrometer, vernier caliper, voltmeter, or oscilloscope to use. These are the tools of the trade and they should select the tool which is capable of measuring the particular parameters with the accuracy and precision required. However, you will need to tell them which device to use if the measurement requires unusual equipment or the environmental conditions prevailing require that only equipment be selected that will operate in such an environment. In such cases the particular devices to be used should be specified in the test or inspection procedures. In order to demonstrate that you selected the appropriate device at some later date, you should consider recording the actual device used in the record of results. With mechanical devices this is not normally necessary because wear should be detected well in advance of there being a problem by periodic calibration. 

Rubber blends with cure rate mismatch is a burning issue for elastomer sandwich products. For example, in a conveyor belt composite structure there is always a combination of two to three special purpose rubbers and, depending on the rubber composition, the curatives are different. Hence, those composite rubber formulations need special processing and formulation to avoid a gross dissimilarity in their cure rate. Recent research in this area indicated that the modification of one or more rubbers with the same cure sites would be a possible solution. Thus, chlorosulfonated polyethylene (CSP) rubber was modified in laboratory scale with 10 wt% of 93% active meta-phenylene bismaleimide (BMI) and 0.5 wt% of dimethyl-di-(/ r/-butyl-peroxy) hexane (catalyst). Mixing was carried out in an oil heated Banbury-type mixer at 150-160°C. The addition of a catalyst was very critical. After 2 min high-shear dispersive melt mix-... 

The turbine is a special type of centrifugal pump (Figure 3-14) and has limited special purpose applications. 

Figures 5-3 and 5-5 illustrate a few of the types of impellers used for mixing. They may be basically classified as axial, radial and mixed. In general the most generally applicable are the. 3-bladed propeller, the flat-blade turbine, the curved blade turbine, and the paddle. The many other designs are either modifications of these or specially designed for a very special purpose with respect to a fluid system and/or its performance.

There are many other types and variations in addition to those listed, although they are usually special-purpose trays and not necessarily generally adaptable. 

Well cementing materials vary from basic Portland cement used in civil engineering construction of all types, to highly sophisticated special-purpose resin-based or latex cements. The purpose of all of these cementing materials is to provide the well driller with a fluid state slurry of cement, water and additives that can be pumped to specific locations within the well. Once the slurry has reached its intended location in the well and a setup time has elapsed, the slurry material can become a nearly impermeable, durable solid material capable of bonding to rock and steel casing. 

Ref 3 contains the following requirements and criteria for special purpose silica Type I (alkaline), Type II (acid), and Type III (hydrophobic) ... 

Almost all designs of WT boilers have multiple banks of special-purpose tubes (water walls, boiler bank, tube bundles, etc.), although a particular type of WT boiler, the coil boiler, typically has only one coiled tube. 

Some Types of Glass for Special Purposes iHere we mention only a few of the glasses which are made for special... 

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