Show r A stearn steam and A air inflow flow meter WRITTEN FOR THE MINING REVIEW over a hundred years have passed since james watt perfected a steam engine with bract cal operating qualities yet up to the present time in neither the generation transmission or utilization of steam has the just due of operating economy been realized the engineering profession Us ils proud of the many advances made in the construction construct on of boilers the provision of suitable steam transmission equipment and the perfecting of highly efficient engines and turbines but in the really vital point measurement the engineer en ineer has had to be content like watt with the knowledge that enough steam was being generated to do a certain certa n amount of work though he has kept an accurate record of coal and water consumed by boilers he has had comeans no means of knowing how much steam was being delivered to the prime mover how much utilized how much wasted the necessity for the conservation of our national resources and the sharp competition which makes every economy however slight a matter of great importance impressed the eng of the general electric company over four years ago with the fact that a means of doing away with guesswork guess work in handling steam would be a wonderful boon to the engineering world experiments were undertaken at that time with a view to perfecting a practical steam meter and as a result of over a thousand actual tests and the expenditure of large sums of money such an instrument is now on the market there have been developed a recording steam flow meter two types of indicating steam flow meters and an indicating air flow meter each of which will accurately measure the rate of flow of steam air or other gases as the case may be in any size pipe under any conditions of pressure and temperature met in iii commercial bract ce the principle governing the action of the flow meter is a modification of that beadil 7 set L the nozzle plug 17 4 61 1 10 ess d 72 recording steam flow meter showing automatic automat c pressure corrective device of the tube A brass nozzle bozze plug screwed into the pipe at the point where the flow is r measured nea the nozzle plug carried two sets of openings a leading set fac ng the direction of flow and extend extending ng diametrically across the pipe and a trailing set consisting of two openings at 90 degrees and one at degrees to the direction of the flow the impingement of the steam against the leading openings sets up in ill them a pressure equal to the pressure plus the pressure due to the velocity head while tile the t trailing railing set is acted on by the static pressure less t that hat due to the velocity the difference in these values is a measure of the velocity and for constant temperature and pressure gives the rate of flow the pressures existing in the two sets of open openings are communicated through separate longitudinal tubes to the outer end of the plug and from there by 14 inch iron pipes to the meter records recording ng steam flow meter the recording steam flow meter type R form D is a curve drawing instrument accurately calibrated to record the total rate of steam flow in pounds per hour in any diameter pipe at any condition of pressure temperature or mol moisture sture in this meter there are two aylin cylindrical adrical hollow cups filled to about half their height with mercury and joined together at the bottom by a hollow tube this U tube is supported on and free to move as a balance about a set of knife edges the two pressures obtained by the nozzle plug are communicated to the cups by flexible steel tubing whereupon the difference in pressure is equalized by a rising of mercury in the lefthand left hand cup and a falling in the right hand cup due to the displacement of the mercury the beams beam carrying the cups tilts on the knife edges until the moment of the counter weights on the extreme right of the meter exactly balances the moment caused by the displacement of the mercury in the lefthand left hand cup the motion of the beam is multiplied by levers and is registered by a pen the time element of the meter consists of an eight day clock driving a drum and feeding paper at the rate of one inch per hour charts are supplied in sizes to measure a flow of from 2000 to pounds per hour and of sufficient length to last one month the rate of flow can be read at an instant or the average rate of flow calculated for a given time the meter is adapted to any condition of pipe diameter pressure superheat or moisture by a hand adjustment of a correction weight on a graduated arm A chart supplied with the met meter er shows the correct position for any existing cond condition tion if the pressure in the steam main var varies ies more than ten pounds from normal compensation pensa tion is necessary for the error thus introduced an automatic pressure correction device consisting of a hollow spring similar to the pressure spring in a steam gauge is connected so as to be influenced fluen ced by the static pressure of the steam at the point where the flow is being measured any variation of the static pressure causes tile the spring to expand or contract and th s movement actuates tile the small correction counterweight counter weight and affects the movement of the pen in su such ch a manner that the recorded rate of flow is correct i the meter weighs fifty five pounds complete and is finished in nickel and dull black As the glass front of the cover is removable the working parts of the meter a are re readily accessible at any time indicating steam flow meters the type I 1 form F steam flow meter will meet general requirements where an indicating rather than a recording instrument mentis is required owing to its simplicity of construction light weight and durability it will be found especially useful for testing work cocat ng leaks etc the meter will indicate the rate of flow of steam in any size arpe p pe under any conditions of ti 11 indicating flow meter temperature or moisture at the p pressure assure range for which the individual meter is designed these ranges are low pressure ten to forty pounds abs med urn um pressure twenty to eighty pounds guage high pressure seventy five to pounds gauge the meter consists of an iron casting cored out to form a U tube and partially filled with mercury the difference in pressures as transmitted from the nozzle clug plug causes a difference in the mercury levels and the displacement of the mercury actuates a pulley by means of a small float suspended by a silk cord the pulley moves a small U magnet on the end of the shaft next to the dial in proportion tion to the change in level of the mercury in the U tube the indicating needle is mounted in a separate cylindrical casing the pivoted end consists of a bar magnet free to turn in the same plane as the magnet on the inside of the meter the mutual attraction of the two magnets keep them parallel a packed joint to transmit the motion of the pulley to the indicating needle is thus eliminated proper adjustments for the existing conditions of pipe diameter pressure and temperature pera ture are readily made by setting the graduated cylinder which actuates the rack carrying the pointer when these settings are made the rack is rotated by hand until the pointer coincide with the indicating needle the point on the calibrated dial at the intersect on of the needle and pointer gives the true instantaneous rate of flow in pounds per hour per square inch pipe area this meter is finished in nickel and black japan and weighs only twenty five pounds A leather hand strap is supplied for car carrying it air flow meter the type I 1 form F indicating air flow meter is identical in principle and method of operation with the type 1 form F Ind indicating steam flow meter except that water is used in the U tube as a working fluid and the chart dial is calibrated to read in cubic feet free air per minute at seventy degrees fahrenheit per square inch pipe area the air flow meter is etc in such a case unless the meter cart can be placed so close to the boilers that steady flow conditions exist for the ex existing stIng conditions is necessary after in stal lation installation station piping arrangements are nat not interfered with whatsoever in installation since it is necessary only to dr 11 a one half inch hole in the pipe and insert the nozzle plug the plug must be placed in hi a straight run of pipe at least ten pipa pip diameters from a preceding elbow or tee and at least two pipe diameters before a following tee or elbow the same e plug is used for all types of meters steam or air the only difference being in the method of piping to the meter the steam meter can be placed at any desired position below the level of the nozzle plug provided the one fourth inch iron pipes to the recording steam flow meter made in two ranges low pressure twelve to thirty five pounds abs and h gh pressure ten to pounds gauge calibration all meters are carefully calibrated at the factory for foi operation under steady flow turbines to heating systems for manufacturing fac turing purposes etc it is not necessary to the meter after installation the meters will not however accurately measure a periodically intermittent flow such as is required by intermittent flow turbines reciprocating engines pumps meter has a slight doNn downward ward s slope ope throughout As the piping for an a r meter is not filled with water the air maer meter can be placed at any desired position whatsoever above or below the nozzle plug to operate the same meter on different sizes of pipes it is thus necessary only to obtain the proper size nozzle plug for the pipe to 10 be metered uses some of the many uses for which the meters are adapted can be bb zed as follows for reco recording iding the total amount of steam generated by a battery of boilers for equalizing the load on individual boilers of a battery for discovering of internal leaks in boilers as shown by the diff difference arence in the water input and the steam output for ning the deterioration of ef licie ncy of a boiler due to formation of scale etc for determining the efficiency of stoking etc for measuring the amount of steam sold for power heating or manufacturing purposes 1 i 1 for discovering losses orl originating I 1 gina ting from leaks between boilers and points of consumption which could not ba otherwise detected as in defective traps gaskets valves etc the great value of these meters has already been demonstrated in many instances in one remark remarkable abla case the boilers of a factory consumed one quarter the amount of coal on sundays when the fac tory was completely shut down as on week days when in full operation of course the engineer knew that steam was being lost but was unable to locate these leaks in the several miles of all sizes of steam pipes the steam flow meter located the leaks and affected a very considerable saving in steam meters have been tried out in more than fifty power plants and factories and found 1 thoroughly y practical being accurate easy to install interchangeable under all conditions light economical cheap and possessing a long life |