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vide a pressure reducer so that its pressure will not be too high at the burner. The illuminating gas is turned on first and ignited, after which the oxygen supply is regulated, so that a good-burning flame is secured.
Lead Burning.-Lead burning consists in melting the metals and causing the parts to flow together and become joined without the aid of solder. It requires considerably more skill than any other form of brazing or soldering. A long step toward success may be taken by the proper arrangement of the work. It is usual to provide something which may serve as a mould or guide for the melted metal. For example, if two lead sheets are to be united by soldering, they are laid on a sheet of some non-heat-conducting substance, such as brick or asbestos. The work in the immediate neighborhood of the joint is carefully scraped so as to remove all oxide or scale which would tend to bind the melted lead and prevent it from flowing freely. The metal at the seam is heated by a very hot bit or the flame from a blowpipe, so that there is a uni- . form flow of lead across the seam. It is sometimes necessary to add more lead to the seam by melting a strip held in the hand. A flame of some sort is the most satisfactory source of heat for the average lead-burning job, because not only is the heat more uniform, but also more intense, and the lead melts at the desired point before the surrounding metal becomes sufficiently hot to soften. There are several types of blowpipe for this purpose on the market. The flame is usually small, sharp-pointed, and very intense. Lead burning is absolutely necessary, and is insisted upon in certain classes of work, for instance, in lining tanks with lead for chemical solutions, or for joining the grids and lugs of storage batteries.
Directions for Lead Burning: To connect the various plates comprising an element, the Gould Storage Battery Company advise the use of a special fixture to insure accuracy in spacing. Be careful to select the proper spacer (Fig. 36), and attach it to the burning-rack. Place the plates on the burning-rack so that the lugs extend through the slots in the spacer. Fit the connecting strap over the lugs. Adjust the spacer by the adjusting nuts until the strap is at the proper height on the lugs. Using the flame,
melt the lug to be burned and the adjoining material until they tend to run together. Using a piece of burning strip, melt the end thereof and fill in around the lug until the whole is a molten mass. Allow the joint to cool and cut off the protruding end of the lug with a pair of end-cutting pliers. Melt the remaining end of the lug till it flows into the strap. Repeat until all plates are burned to the strap.
11 Burning Plates to Old Straps: The storage battery company
Fig. 36.-Gould Burning-Rack for Supporting Plates When Burning
Plate Lugs to Busbars.
furnishes connector straps for nearly all the modern types of batteries. Sometimes it happens, however, that a battery of an old model or of a manufacture seldom used will be set up with straps that cannot be duplicated. Under these circumstances the old straps should be utilized. With the hacksaw cut off the plates.
Cut slots in the strap, using the old lugs as a guide. Cleanse the strap thoroughly in ammoniated water and scrape clean. Using the proper spacer, proceed as described above.
To Burn Terminal Connector to Pillar Post: Scrape the parts clean. Fit the terminal connector to the pillar post. If the terminal connector does not set low enough, ream the terminal with the triangular scraper until the fit is exact. Heat with flame until the inside of terminal connector and outside of pillar post are one molten mass-throughout. Fill in with molten, burning material and allow to cool. To burn connecting link to pillar posts, proceed as above.
AUTOMOBILE LIGHTING AND STARTING. BATTERY DEFECTS AND RESTORATION SUMMARIZED.
Broken or cracked cell jar. Low level in one cell.
Replace with new jar. Plates sulphated.
Gravity will not rise on charge. Long slow charge at min. rate. Active material crystallized. Lack of acid. Gravity will not rise on charge. Mix new electrolyte and fill
cells recharged. Electrolyte low. Overheating
Refill with water or electrolyte,
depending on gravity. Rapid charging. Overheating
Regulate generator output. Solution level too high. Electrolyte leaks out of vents. Draw out surplus with syringe. Cracked cell cover. Battery box eaten.
Do not fill cells so much. Defective sealing.
Augment generator output;
charge battery from outside
source. Charging too fast. Overheating.
Charge at lower rate. Cell Buckled or warped plates.
temperature must not be
above 100° F. Short circuits.
Battery loses charge rapidly Go over external wiring. Large sediment deposit.
Clean out sediment. No current in cold weather. Battery frozen.
Cannot usually be repaired.
Try slow long charge.
tion. Separator failure. Impure water.
Use only distilled water. Electrolyte too rich in acid. Dilute rich electrolyte. Separators charred or punc-Overheating.
Replace separators. tured. Loss of charge.
Maintain level of electrolyte. Lights uncertain. Battery nearly discharged. Give boosting charge from out
side source. Current output low even though Gravity of electrolyte too low. Bring gravity up to 1.280° by liquid is at proper level.
charging. Excessive current consumption. Gravity of electrolyte down to Give long slow charge 3 to 5
amps. rate. One cell defective. Total voltage low.
Rebuild poor cell. Poor separators.
Weak current. Active material shedding. Large sediment deposit. Rebuild battery. Battery not properly fastened Cell jars break or crack. Fit proper hold-down clamps.
down. Acid escapes through vents. Terminals corroded.
Clean with ammonia or wash
ing soda; cout with vaseline. Excessive gassing:
Metal battery box corroded. Use lower charging rate-coat Poor box ventilation.
box interior with asphaltum
paint. Battery discharged.
Starting motor will not start Give thorough charge from engine.
outside current. Lights burn dim. Generator not charging prop- Battery needs frequent boost- Overhaul generator. erly.
Regulate for proper charging
Battery-Charging Methods—Currents and Voltages—Electrolytic Rectifiers
-Vibrator Rectifiers-Mercury Arc Rectifiers–Rotary Converters-
THE equipment to be used in charging storage batteries depends entirely upon the type and size of batteries to be charged, the current voltage and character available for charging, and the individual characteristics of the batteries themselves. Storage batteries can be charged only with direct current, i. e., that which flows always from the same direction. It is evident that the use of alternating current, if the mains were attached directly to the battery, would result in rapid changes in the interior of the cells, and as the flow in one direction would tend to neutralize that in the other, the plates would depreciate very rapidly. If alternating current is the only kind available, this must be transformed or rectified into direct current. All cells cannot be charged at the same rate. The greater the capacity of the battery and the higher its discharge rate, the greater the amperage of the current that can be used in charging. While the voltage of a storage, battery made of certain materials will not vary with the size, the amperage or current output increases with the plate size and number. A leadplate storage battery no longer than a thimble will have just as high voltage as one as big as a barrel. It will be evident, however, that if too much current is passed through a small cell it will be injured, whereas too little current passed through a large cell will have but little effect on changing the character of the plates.
There are two general methods in use for charging either the sulphuric-acid-lead batteries or the alkali-nickel-iron batteries used in the various commercial applications. The first method, and the