Document EdRRxGYmqz1baELOm4MByoy0b

918 CHAPTER 44 1950 Guide Moisture Control .by Liquid Absorption Offers a Useful Air Conditioning Tool, by F. H. Johnson (Heal ing, Piping and Air Conditioning, Deoimber, 1938, p. 782). ,,-.***,.**** Air Processing Needs of Plywood Plane Parts, by F. O. Jordan {Heating and Ventilating, April, 1944,p.67). The ^Tifinp^ring Control of Some Solvent Hazards in War Industries, by 8. C. Rothman (A.8.H.VJ2. .Transactions, Vol.'50; 1944, p. 319). . . 4 Air Conditioning as Applied in Theatres and Film Laboratories, by D. C. Lindsay {Transactions Society 'of Motion Picture Engineers, April, 1927, VoL XI; No. 80, p. 333-866). . ' . , ,, Industrial Air Conditioning, by F. F. Stevenson {Seating, Piping and Avr Conditioning, May, 1948, p. 100; June, 1948, p. 94; and Jack F. Salsburg, July, 1948, p. 88, and Oct. 1948, p. 93). Industrial Air Conditioning, by Charles 8. Cave (Industry and Power, July 1946, p. 67; Sept. 1945, p. 67). Reducing Heat Loads In Industrial Air Conditioning, by L. R. St. Onge (Refrigerating Engineering, Jan- nar%iT^i<?igt, and Sound ControlledinWestern Electric's New Plant, (Hearing, Piping and Air Conditioning, ;N New^B& Plant Addition, Poughkeepsie, N. Y., by J. T. Browne (Hearing. Pepin# and Air Conditioning, an.Xir Conditioning Design Conditions for Various Industries,- (Hearing and VentiZattng, May, 1949,-p. 70; ^Phbto'Studios Need Conditioning for Both Processing and Comfort, by E. E. Herbacek (Hearing, Piping and Air Conditioning, June, 1949, p. 85). Foundry Ventilation, by Jim Black and Lester T. Avery (Hearing, Piping and Air. Conditioning, March, pi 71, April, p. 78, and May, p. 89,'1947). . Dust Control for Foundries, by B. F. Postman (Hearing and Ventilating, Dee. 1948, p. 66; Jan. 1949, p. 78). Foundry Cuts Its Dust, (Editorial. Heating'and Ventilating, Feb. 1949, p. 86). Fog Removal in Industrial Hants, by R. C. Soronen (Heating, Piping and Air Conditioning, April, 1949, P* *Air Conditioning Crane Cabs, by R. D. Darrah (Refrigerating Engineering, May, 1949, p. 440). .. Air-Conditioned Crane Cabs, by B. R. Small (Industrial Hygiene Foundation, Preventive Engineering Series, Bulletin No. 4, 1947). Health, Safety and Efficiency . Lectures, The Inserrice Training Course in Environmental Controls for Industrial Processes, University of Michigan School of Public Health, 1946: Environmental Controls in Industrial Health, by R. R. Sayers; 'Principles of Industrial Process Ventilation, by W. N. Witheridgje; The Selection and Maintenance of Equip ment for Proofs Control, by R. P. Warren; Environmental Control of Industrial Processes as Affected by Foundry Lay-out, by John Linabury; Foundry Ventilation, by J. M. Kane; Control of Welding Hazards, by W. C. L. Hemeon; Environmental Control of the Metal Cleaning Prooeases, by F. A. Patty; Painting, ' by t. F. Mooney: Health Hazards in the Electroplating Industry, by William Blum; Industrial Housekeeping and Sanitation, by John Soet. . Air Sanitation and Industrial Ventilation, by W. N. Witheridge, Detroit, 1946. . An Investigation of the Bacterial Contamination oi the Air of Textile Mills with Special Reference to the Influence of Artificial Humidification, by W. F. Welle and E. C. Riley (The Journal of Industrial Hygiene and Toxicology. Vol. 19. No. 10, December, 1937). . ..... Industrial Cooling as a Production Aid, by J. Partington. Jr. {Beating and VentOgtingtApm, 1944, p. 47). . Industrial Exhaust Ventilation in Industrial Hygiene, by A. D. Brandt (A.8.H.VJS. Tbanbactions, ^^Cbntrol^of>industrial Atmospheres, by W. N. Witheridge (A.S.H.VJ5. Transactions, Vol. 61, 1945, p. ^Mine Ventilation and its Relation to Health and Safety, by D. Harrington (A.8.H.VJE. Transactions, ^Ventibition Requirements for Industrial Solvents, by W. C. L. Hemeon {Heating and Ventilating, Decem ber. 1945, p. 95; January, p. 69; March, p. 82; and April, d. 79, 1946). w. Guides lor industrial Ventilation, by Allen D. Brandt (Heating and Ventilating, March, 1946, p. 67). Industrial Dust'Explosions/by Hylton'R. Brown {Heating and Ventilating, March, 1946, p. 73). ' Supply Air in Plant Ventilation, by J. B. Skinner and William M. Pieroe (Hearing and Ventilating, May, 1946 p. 67). Wbat Air Conditions Make for Comfort in Industry?, by H. A. Mosher (Heatin, Piping and Air Con- dtrfontng^ Agnl,^^ R^juirementfl for Workers in Factories, by H. A. Moeher (Heating, Piping and Air Can- <**OIHot Weather limits Hard Work. (Brief summary of investigation done tor Army Quartermaster Corps, by Department of Physiology, Medical School, Cmveraity of Indiana. Heating and YentUating, August, Methods Uaed in Determining the Health Hassids Arising from the Inhalation of Various Chemicals, by Francis F. Heyroth (A.S.H.V.E. Journal Section, Heating. Piping and Air Conditioning, January, 1917, d. 109. and discussions. Heating, Piping and Air Conditioning. April, 1917, p: 113). Air Recirculation from Exhaust Systems, by John M. Kane (heating and Ventilating, April. 1917, p. 75). Should Air Bo Recirculated from Industrial Exhaust Systems? by Allen D. Brandt (Heating, Ptptng a"^l>hmnidi]icaSon Mettmd^ami Applications, by John Everetts, Jr. (A.S.H.V.E. Journal Section, Heating, Piping and Air Conditioning. December, 1915, p. 121). * , .. . ... ,, Snvv Silting Dynamic Dehumidifieation Equipment, by E. R. Queer and E. R. McLaughlin (A.S.H.V.E. Journal Siction, Heating. Piping and Air Conditioning, Jsnuary, I917, p. 1(B). CHAPTER 45 . at INDUSTRIAL EXHAUST SYSTEMS Classification of Systems, Hood Design Principles, Capture Velocity and Hood Suction, Duct System Design, Resistance of System, Efficiency of System, Air Flow Producing Equipment, Protection Against Corrosion and Abrasion IN many industrial plants some type of exhaust system designed tor collect and remove dusts, fumes, mists, vapors and gases is essential in order to promote efficiency, economy, and safety of operation. Defini tions of these various contaminants are included in Chapter 8, Air Con taminants. The theory of air flow in an exhaust system in the following paragraphs A to D will be found in a publication1 of the American Foundrymen's Association. A. When the air flow producing equipment of an exhaust system is properly oper ated, it will produce a negative pressure (below atmospheric) in the exhaust side of the system sufficient to overcome ail resistance and to sustain the desired air velocity; and, further, will overcome all resistances on the discharge or positive pressure side of the system so that the air drawn through exhaust inlets will be discharged against atmospheric pressure. B. An exhaust system is entirely dependent on a sufficient volume of air flowing into the exhaust inlets to catch the matter to be exhausted before such matter has an op portunity to diffuse into the general atmosphere of the work place or room. . C. The velocity of the air flowing into an exhaust inlet is usually of secondary importance, and becomes an essential factor only when a certain velocity is required to overcome some force acting on the matter to be caught. The velocity within an exhaust system is only important to the extent that it shall be sufficient to convey the entrained matter and prevent it from settling or dropping out in the piping sys tem. Velocity in terms of velocity pressure is most essential in designing a system because it is the basis upon which all calculations are made. In,testing and checking a system the velocity, as determined from the velocity pressure reading obtained by means of a Pitot- tube, is the only true indication of the exact air flow in a pipe or system. :`D. The total pressure within an exhaust system is only of importance in deter mining the power required to operate the system. Total pressure tests do not in-, dicate the proper functioning of an exhaust system as related to the volume and velocity of the air flowing into an exhaust inlet. '; General design information is included in this chapter which is intended to relate primarily to industrial exhaust systems. ' CLASSIFICATION OF SYSTEMS In general there are two basic layouts of exhaust systems,: the central and the multiple unit system. In the central system a fan is located nearthe center of operations with a piping system radiating , to the various machines to be served. In the multiple unit system, which is sometimes employed where the machines to be served are widely scattered, or where the operations are apt to be independent or inteimittent, small individual exhaust fans are located at the center of the machine groups or at each machine. The unit.arrangement has the advantage of flexibility. Exhaust systems may be classified with respect to the nature of the. material to be handled by them as (a) those handling dusts and certain fumes and mists of large particle size, and (b) those handling vapors, gases and certain fumes and mists of small particle size. Design details differ in systems serving dust producing operations and those exhausting the 019