Enclosure design

The scope of this chapter is to show how to select a strategy and to make calculations to provide efficient room air conditioning for an industrial enclosure. Design examples for simplified scenarios include different ways to condition industrial halls. 

The potential for interference with the normal operation and maintenance of a process vessel is high. A major design effort is required to overcome this disadvantage. All aspects of the process vessel operation must be considered. Lines of sight for process vessel and crane operators, access for crane-held ladles and buckets, process vessel movements, and maintenance access must be accommodated by the enclosure design. This is more easily achieved in a new installation. 

Enclosure design on retrofit cases becomes very difficult and may require a compromise between process vessel operation and fume capture performance. 

Air Extraction from the Enclosure A textbook approach to enclosure design for a hot process would follow a procedure of determining the in-draft veloc-... 

Evolution in telescope making since the Palomar has not been limited to the area of optical production. The alt-azimuthal mount has become the established solution since the Bolshoi 6 m telescope, for its superior mechanical performance and the compact, cost-efficient enclosure design it allows. Better understanding of the properties of atmospheric turbulence allowed a more accurate characterization of a telescope properties, a more balanced approach towards specifications and error budgeting and a better understanding of the utmost importance of site selection. Any ground-based telescope of appreciable size will be primarily limited by the effect of atmospheric turbulence, not to mention the proportion of photometric nights allowed by weather conditions. 

An outdoor enclosure designed against rain, sleet, and damage from external ice formation. They are not dust tight, snow or sleet (ice) proof. 

An outdoor enclosure designed to protect against dust and water and to operate covered with ice or sleet. 

Enclosures, even partial enclosures, containing equipment handling flammable, combustible, ortoxic materials may permit the accumulation of hazardous concentrations of these materials within the enclosure, potentially resulting in fire, explosion, or personnel exposure. Where the possibility of a flammable spill or release within an enclosure exists, the enclosure design should include a relevant selection from the following features noncombustible construction, adequate ventilation, drainage, appropriate electrical classification, flammable vapor detection, isolation and alarm, and internal automatic sprinkler or water spray protection. 

The results of deposition studies using H2S are summarized in Table III. The sparsity of the data reflects the problems of conducting this type of experiment. The emission rates shown are the values measured immediately before and after making deposition measurements, and are used to calculate the deposition rate. It is clear in the case of the seawater surface that changes in natural emissions complicate the study to such an extent that interpretation is impossible. Furthermore, it should be noted that the nature 01 enclosure designs provides elevated concentrations of emitted gaseous species, and it is likely that the measured emission rates already include a depositional component. The concentration of sulfur species added to the chamber in these studies is comparable to that already present, and the actual deposition rates would probably be higher at ambient reduced sulfur levels. 

The plausible universe of alternatives to decaBDE for achieving fire safety in TV enclosures includes chemical substitutes, inherently flame resistant materials that eliminate the need for added flame retardant chemicals (for example, steel or aluminum), and TV re-design options that eliminate the need for flame retardants by separating the enclosure from the heat source. Alternative enclosure designs that eliminate the need for added chemical flame retardants and meet or exceed performance specifications (including flame retardancy) are considered inherently preferable alternatives, particularly if they are derived from benign chemicals (and safe processes) and are recyclable or compostable at end of life. 

Hood and enclosure design, (i) (A) It is the dual function of grinding and abrasive cutting-off wheel hoods to protect the operator from the hazards of bursting wheels as well as to provide a means for the removal of dust and dirt generated. All hoods shall be not less in structural strength than specified in the American National Standard Safety Code for the Use, Care, and Protection of Abrasive Wheels, B7.1-1970. 

Cabinet. An enclosure designed either for surface or flush mounting, and provided with a frame, mat, or trim in which a swinging door or doors are or may be hung. 

Cutout box. An enclosure designed for surface mounting and having swinging doors or covers secured directly to and telescoping with the walls of the box proper. (See Cabinet. )... 

In a practical sense, enclosure designs often require some accommodation. For ease of maintenance, enclosures can be constmcted to rise upward and away from the machinery by overhead cranes. Access openings can be provided by tunnels lined with acoustically absorbent material (in effect, mnfflers). Access for controls can be designed with hinged covers that lift easily, or the controls can be relocated. Some enclosure panels can be lifted automatically at the correct point in the machine cycle to provide access. Ducts can be provided with small ventilating fans to prodnce a controlled cooling airstream and, if combined with filters, can allow a controlled environment for some operations. 

The common enclosure design (Fig. 5.141) and the use of combination starters offer both economy and ease of installation in multiple motor control installations. In addition, motor control centers (MCCs) provide proper coordination between short-circuit protective devices and the controller. Since MCCs are engineered systems, the components are closely coordinated to work together, and the unit is rated for a particular value of short-circuit interrupting duty at the point of its installation. MCCs may contain a molded-case circuit breaker and starter, or a fused switch and a starter. 

Automatic machines and high-production machines could have enclosures designed and installed to guard the employee from the entire drilling operation. 

The enclosure designs have sound well-tested practices. To support this, there are design testing guidelines, standards, testing companies, agencies, and consultants. 

An enclosure designed to meet the explosionproof requirements of the US Mine Safety and Health Administration (MSHA) requirements as defined in 30 CFR, Part 18, (Schedule 2G).The equipment is to be used in mines... 

An indoor enclosure design without knockouts for use in industries where it is desired to exclude such materials such as foreign objects, e.g., dirt, dust, lint fibers, flyings, and ingress of liquids, e.g., dripping and light splashing. 

As mentioned earlier, there are several basic types of environment in which most process analyzer installations will take place. In order to address these requirements, different levels of enclosure design and control of the internal instrument environment are required. In the subsequent subsection, these issues will be addressed. 

The system of passive heat removal from the protective enclosure, designed to limit pressure in the protective enclosure in LOCAs. 

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