Document gbj01p919GDB7xq0bpxM12zDV

"KKll'AN society of Heating uttuiNEEHs Guide 7. It is best not to connect a meter body to more than one service. r,. -*>? * 8. Special instructions are furnished for metering a turbulent or pulsating fl0w . Meter for Hot Water S The lack of a suitable meter for the measuring of the water supni J in a hot water heating system has been in a great measure respond)? for the unpopularity of district heating with hot water. Pipe Line Designfor CentralStation HeatiRngE, bFyEBR. TE.NGCiffEorSd (A.S.H.V.E. Transactions, VqL jy lQv. ," Engineering and Cost Data Relative to the Installation of Steam Distributing Systems in a Lorre n, F. H. Valentine (A.S.H.V.E. Transactions. Vol. 22, 1916). ""M Transmission of Steam in a Central Healing System, by J. H. Walker (A.S.H.V.E. Transa*-*,.; Vol. 23. 1917). *^050 Efficiency of Underground Conduit, by G. B. Nichols (A.S.H.V.E. Transactions, Vol. 23,1017). Economical Utilization of Heat from Central Plants, by N. W. Calvert and J. E. Seitef (AS.H vt> Transactions, Vol. 30,1924). n,VlE Standard Connections for Condensation Meters, (Nt.H~A. Proceedings, Vol. XU. pp. 63-76). Installation and Maintenance of Steam Meters, {N.DM,A. Proceedings, Vol. XIU, pp. 177-183). Inaccuracy in Flout Meter Calculations, (N.DM.A. Proceedings, Vol. XIII, pp. 183-193). Testing ofSteam Meters, {N.D.H.A. Proceedings, Vol. XIV. pp.. 272-276). Meter Accuracy Guarantees, (N.D.H.A. Proceedings Vol. XIV, pp. 276-277), Ejfecl of Pulsations on the Flow of Gases, {N.DJ3.A. Proceedings, Vol. XIV. pp. 277-281). Meter Connections, (N.D.H.A. Proceedings, Vol. XX, pp. 126-143). Layoutfar Testing Meters, (N.D.H.A. Proceedings, Vol. XX, pp. 391-392). Characteristic Meter Calibration Curves, (N.D.H.A. Proceedings, Vol. XX, pp. 444-453). EXHAUST SYSTEMS FOR DUST AND REFUSE Tvoes of Systems; Important Requirements for An Efficient System; Air Velocity Required; Typical Layout and Calculations; Sweeting the Fan; Collectors; Design of Hoods; Conveyor Pipes; Maintenance of System. THE removal of dust and refuse created in factory and mill operations must be properly provided for in accordance with definite statutory requirements in many states. The type of system to be used is determined by the industry served, kind of material handled, and the work to be accomplished. TYPES OF SYSTEMS There are two general arrangements, the central and the group systems. In the central system a single or double fan is located near the center of the shop with a piping system radiating to the various machines to be served. In the group system, which is sometimes employed where the machines to be served are widely scattered, small individual exhaust fans , are located at the center of the machine groups. The group arrangement has the advantage of flexibility. Exhaust systems are also classified by the means employed to collect dust or other material handled. The dust or refuse may be collected and controlled by enclosing hoods, open hoods, inward air leakage or by exhausting the general air of the room. With some classes of machinery it is not feasible to closely hood the machines and in these cases open hoods over or adjacent to the machines are provided to collect as much as possible of the dust and fumes. In this class come such machines as rubber mills, package filling machinery, sand blast, crushers, forges, pickling tanks, melting furnaces, and the unloading points of various types of conveyors. The open hoods should be placed as close to the source of dust or fumes as possible, with due regard to the movements of the operator. When the hood has to be placed at some distance above the machine it should be large enough to encompass an area of considerable extent as diffusion is usually quite rapid. Consideration must also be given to the natural movement of the fumes. For those that are lighter than air the hood should be over or above the machine and where a heavy vapor or dust-laden air at ordinary temperature is to be removed, horizontal or floor connections are required. If it is attempted to remove heavy dust such as lead oxides by an over- 383