Part 13 (1/2)
Where it is desirable to make a continuous seam, a special machine is required, or an attachment for one of the other types In this forhly cleaned and is then passed between copper rollers which act in the same capacity as the copper dies
_Other Applications_--Hardening and te dies and setting the control and ti the metal to the proper color, when it is cooled in the usualthe work in the jaws and heating until the flux, then the spelter hasof rivets can be done by bringing the dies down on opposite ends of the rivet after it has been inserted in the hole, the dies being shaped to form the heads properly
Hardened steel may be softened and annealed so that it can bethe dies of the welder to each side of the point to be softened
The current is then applied until the work has reached a point at which it will soften when cooled
_Troubles and Re methods have been furnished by the Toledo Electric Welder Company and are recommended for this class of henever necessary
To locate grounds in the prie side of the circuit, connect incandescent la piece of laure 43a For 110 volts use one lamp, for 220 volts use two lamps and for 440 volts use four lamps Attach one end of the lamp cord to one side of the switch, and close the switch Take the other end of the cord in the hand and press it against soht Paint, grease and dirt act as insulators and prevent electrical contact If the lahts, the circuit is in electrical contact with the fraht, connect the wire to a terht, the circuit, coils or leads are in electrical contact with the large coil in the transformer or its connections
If, however, the laht in either case, the lamp cord should be disconnected from the switch and connected to the other side, and the operations of connecting to welder frame, dies, terminal blocks, etc, as explained above, should be repeated If the laround” is indicated ”Grounds” can usually be found by carefully tracing the primary circuit until a place is found where the insulation is defective Reinsulate andis clear If the ground can not be located by observation, the various parts of the primary circuit should be disconnected, and the transforulator, etc, tested separately
To locate a ground in the regulator or other part, disconnect the lines running to the welder from the switch The test lamps used in the previous tests are connected, one end of la post of the regulator Connect the other side of the switch to so (This must be a clean connection to a bolt head or the paint should be scraped off) Close the switch If the la or sorounded” to the iron base or core of the regulator If the laht, this part of the apparatus is clear
This test can be easily applied to any part of the welder outfit by connecting to the current carrying part of the apparatus, and to the iron base or fraht, it indicates that the insulation is broken down or is defective
An AC voltmeter can, of course, be substituted for the lamps, or a DC
volt the tests
A short circuit in the pri defective and allowing the bare copper wires to touch each other
This may result in a ”burn out” of one or more of the transformer coils, if the trouble is in the transfor of fuses in the line Feel of each coil separately If a short circuit exists in a coil it will heat excessively Exah and two of them may cross, or be in contact with the fraulator winding is indicated by failure of the apparatus to regulate properly, and soulator coils
The remedy for a short circuit is to reinsulate the defective parts It is a good plan to prevent trouble by exa occasionally and see that the insulation is perfect
_To Locate Grounds and Short Circuits in the Secondary, or Low Voltage Side_--Trouble of this kind is indicated by theto operate To make a test, it will be necessary to first ascertain the exciting current of your particular transformer This is the current the transformer draws on ”open circuit,” or when supplied with current fro table will give this inforh for all practical purposes:
KW ----------------- A 110 Volts 220 Volts 440 Volts 550 Volts 3 15 7538 3 5 25 125 63 5 8 36 18 9 72 10 425 213 107 85 15 6 3 15 12 20 7 35 175 14 30 9 45 225 18 35 96 48 24 192 50 10 5 25 2
Remove the fuses froh to carry the ”exciting” current If no suitable fuses are at hand, fine strands of copper from an ordinary lae wire and will fuse at about 10 a on the a current, and are connected across the fuse clips in place of fuse wire
Place a piece of wood or fibre between the welding dies in the welder as though you were going to weld thehest point and close the welder switch If the secondary circuit is badly grounded, current will flow through the ground, and the small fuses or small strands of ill burn out This is an indication that both sides of the secondary circuit are grounded or that a short circuit exists in a primary coil In either case the welder should not be operated until the trouble is found and removed If, however, the se fuses, then disconnect wires running from the wall switch to the welder and substitute two pieces of No 8 or No 6 insulated copper wire, after scraping off the insulation for an inch or two at each end Connect one wire from the switch to the frame of welder; this will leave one loose end Hold this a foot or so away from the place where the insulation is cut off; then turn on the current and strike the free end of this wire lightly against one of the copper dies, drawing it away quickly If no sparking is produced, the secondary circuit is free froround, and you will then look for a broken connection in the circuit So the above test, as in case one ter wire may be fused if allowed to stay in contact with the die
_The Rehly and dry out the fibre insulation if it is da parts, and that the secondary leads do not touch the fraround is very heavy it may be necessary to remove the slides in order to facilitate the exaround Insulation, where torn or worn through, must be carefully replaced or taped If the transforrounded to the iron core of the transformer or to the secondary, it may be necessary to remove the coils and reinsulate them at the points of contact A short circuited coil will heat excessively and eventually burn out This may mean a new coil if you are unable to repair the old one In all cases the transfors should be protected from mechanical injury or dampness Unless excessively overloaded, transfor a moment's trouble, if they are not exposed to moisture or are not injured mechanically
The most common trouble arises from poor electrical contacts, and they are the cause of endless trouble and annoyance See that all connections are clean and bright Take out the dies every day or two and see that there is no scale, grease or dirt between thehten the bolts running from the transformer leads to the work jaws
ELECTRIC ARC WELDING
This method bears no relation to the one just considered, except that the source of heat is the sa makes use of the flame produced by the voltaic arc in practically the saases
If the ends of two pieces of carbon through which a current of electricity is flohile they are in contact are separated from each other quite slowly, a brilliant arc of flame is formed between them which consists mainly of carbon vapor The carbons are consuh being turned to a gas under the intense heat