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Motor and Pump Repairs Go .[ectronics for the power engineer 1, , A ANNOT, Auoclofu M#or Hand in Hand Good operation is never acci dental. It Is planned in ail its parts, including mainte nance and repairs, says M H Kinsinger, chief mechanical superintendent, Dept- of Sani tation, Sewer Di.v, Washington SUCTION ANO DISCHARGE .flPING determine the pump focotlon, especial!* c. large unit! when piping is byrled In the concrete floor Or even in the feundallenfl The question of where an electri cian's work end* tod 0 machinist'* bogins has almost os indefinite an answer as the distinction between maintenance and repair. In our plant, tor instance, we use couplings, either flexible or solid, between motor and pump on all our units. The. electrician cares (or the motor up to the end of the motorshaft, but the coupling is not included. Pump repairs and alignment of the two. units are the machinist's re sponsibility. In tonne of our large ver tical units a Kingsbury bearing built In the top of the motor carries the en tire thrust of the unit. Here, the machinist is responsible for the thrust bearing fun as though It were a sep arate part. Allgemont. All alignment following repairs to either pump or motor is accomplished by shimming or mov ing the motor. Even though it may be doweled, the only practical thing is to move it, if necessary, to secure perfect alignment. Suction and discharge pip ing determine the pump location, espe cially on large units where piping is buried in concrete. Even though bear ings are renewed we rarely have to change the original motor setting. We use bedplates for the motor, and num ber all shims, marking the location on the bedplate the first time a unit is taken aparc We ore also particular about the gaskets, and make sure the same thick ness fa used In replacing them. These precautions keep the necessity (or realignment to o minimum. Accord- ingly, we dowel both motor and pumpi Actual alignment b accomplished by having (l) the machinist check cou pling flanges with straight edge, feelers, level and dial gage, and (2) the elec trician move the motor, or place shims and bolt it down. When alignment is perfect, the machinist bolts the coupling halves together. For effective repair, work, cooperation between the two crofts is essential. Cleaning Schedule. Maintenance schedules vary with the nature of the service, the amount of help available, and individual piant experience. To start with, I have set up reguior clean ing schedules for tbo operating force, tn power plant work, cleanliness is Number One on the Hit Parade. Our schedule is based on cleaning each piece of equipment at least once a week, and Is divided over three watches a day. It means that operating men are in working contoct with machines regularly and discover faults that would be overlooked on inspections. This cleaning program is the keystone of good maintenance and operation, and improves employe morale- We change packing an some pumps every three months, and on all pumps once a year faecauso sewage imbeds grit in the pecking. Type of packing and frequency of renewal roust be de termined on each job. Several times daily we check oij for quantity; weekly cleaning schedule ol filters and strain ers indicates their condition. Bearings are checked several times on each **(& for heat or wobble. Wo check besrbif clearance aad wear on impellers sad filling rings every sis months si 1 routine measure, and 11 other times if inspection indicates need. Overhauling. Our experience deraco-] strales that pumps need general o*ei-f haul about every (our years. This bl largely determined by wear on ittpei-J lers. Some engineers suggest general] overhaul once a year, but I do not Uror] that program. We keep our pumps bl service until there is evidence of s acedl for repairs through loss of esptcicy.l accidental submerging of pump b] floods, or some other cause. When overhaul time it decided upon1 an effort is made to coordinate work. Motor is overhauled as much si h necessary at the same time the putnpb worked on. Auxiliary equipment, ekotrical circuits, control panels, thnp* bearings, and any other equipment effected by the shutdown are checked and, if necessary, repaired. In dies# days of 2-year delivery on spare psru. the most important phase of an over haul job is polishing up the old cryttd hall and ordering your parts before yo begin to plan tho actual jobMany organitotions hovfr a decided tendency to accept good operation *0 maintenance as a matter of cou Quite often the only time any lion if paid to either is when ,ren" ^ develops. KM (2Jj POWER * Apd lW| ^-The Electron Electron Tubes riant 0/ electronic device* have tmefidoas advance* during the year* in practically every phase er and industrial engineering, ingfy many engineer and elecere confronted with installing, ng and maintaining electronic to* tdth little or no knowledge e them. To help them, thit tils in'easy lessons what elecre, the diScrenl kinds of elecba in common use, and how t adapted as power rectifiers, tt, controllert and frequency 1 in a wide variety of circuit*. rtisTtoN of all electronic devices {tq methods of producing and conmg a flow of electrons. Therefore, rill first leein what electrons are, they are made available, ond tome that govern their action under real conditions. omeera. All mailer is composed oi or more of 92 elements, such as igen, oxygen, nitrogen, carbon, ,'lron, silver, gold. An element is ihsuncc that cannot be separated JeaHy into anything but itself- For pis, hydrogen cannot be separated anything hut hydrogen no matter small it U divided, nor can gold be td chemically into anything but , atom is the smallest division that be made q( any element. Smallest simplest Is the hydrogen atom, at the other end of tho scale of ~ts b the uranium atom. It b the rat and molt complex known, lag neptunium, plutonium, omer. and curium, recently created -witty. P to about 50 years ago tho atom believed to be the final divlalon of ler. Then evidence began to acUta that possibly it was composed Wrtbles. Today through almost `osa experiments by scientists we pi* > April 1948 Atom Structure Eleclrpn, mow l ^ `/ it v \ $ )\\Proio1n83,m6 aa// The hydrogen atom has o proton - thot serves os a nucleus oboul which rototes 0 single electron /Electron \ 0 joof'jt Neutron* \\ V\ *} Proton / j/E/leInctdroianme3t0erft / 9-. -300->*l \ miles \ v Proton the alto of o peo 2 This Is o conception of tho hy drogen otom devised by the English physicist, SW firnest Rutherford /' % / Electrons'-, ^v Nucleus J V____ .x 3 4The hydrogen Isotope hot o preton ond neutron thot ore bound closely together to form 0 mxleus The helium otom has two elec trons thot roiote In 0 single orbit around the compact nucleus er Proton /' \ y <*> Neutron Proton 5 In the nucleus of the helium atom two protons and two neuirons are bound closely together '/ / Neutron C Ulhlum otom ho. lh. oloclmm. D about o nucleus: two In loo,. clutor orbit, on. In outer T Tta nuctauj fh-"'hlum. olw * diagrammed In Fig. 6, includes Ihr.o proton, ond thro, neutron. know this is (rue. Five triads of parti cles have bees found in atoms: 1. Electron, smallest subdivision of electricity, has a negative charge. 2. Proton, an elementary particle, has a positive electrical charge equal to the oegotive charge on the electron; but it weighs 1836 times as much. 3. Neutron weighs about the same as a proton but Is without- an electrical (239) I OS