Welding method and clamping device for steel reinforcements

A welding method for steel reinforcements, wherein electric current flows through the reinforcements, an electroslag pool formed from a solder melted by an electric arc generates a lot of heat to melt the reinforcements, pressure is applied to combine the same; the method uses a clamping device, wherein a sliding chuck is adjustably rotated by means of a bolt handle thereon to enhance a movable clamping seat to clamp the upper reinforcement, then a fixed chuck is adjustably rotated by means of another bolt handle to enhance another movable clamping seat to clamp the lower reinforcement, a crank provided at one side of a main body can be optionally rotated forwardly or backwardly to raise or lower the upper reinforcement, or the upper and the lower reinforcements can be compressed for combining.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a welding method and a clamping device for 
steel reinforcements, and especially to the welding method and clamping 
device for integratedly connecting steel reinforcements. 
2. Description of the Prior Art 
Traditional ways of connecting steel reinforcements in constructing include 
mainly bind welding, interweave welding or bind weldrod welding, steel 
reinforcements in such ways of connecting are lapped, there is much waste 
of reinforcements and cost,.yet bearing ability of reinforcements is 
inferior; moreover, binding or welding in such ways of connecting needs 
highly qualified persons to operate, an ordinary person is impossible to 
do the same work, in this way, workman cost is so high as to be a 
suffering burden to an owner of such businesses. 
In view of this, the inventor of the present invention provides the welding 
method and clamping device for steel reinforcements after long term study 
as well as designing. 
SUMMARY OF THE INVENTION 
Therefore, the main object of the present invention is to provide a welding 
method for steel reinforcements such method can be operated with fast 
speed, short time, simple procedure, high convenience and efficiency and 
also reduces cost. 
Another object of the present invention is to provide a clamping device for 
steel reinforcements for executing welding of steel reinforcements in a 
convenient and smooth way. 
The present invention will be apparent in its objects technical measures 
and effects after reading the detailed description of the preferred 
embodiment thereof in reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
The present invention is now described referring to the drawings regarding 
the steps of its welding method for the steel reinforcements: 
a) Arc striking process: as shown in FIG. 1, an upper and a lower steel 
reinforcements 1, 2 are kept in alignment with each other by their axes, a 
solder tank 3 is provided at the connection of the upper and the lower 
steel reinforcements 1, 2, the solder tank 3 is full filled with solder 
31, then the steel reinforcements 1, 2 are connected to an electric power 
source, and the upper steel reinforcement 1 is lifted up to strike an 
electric arc 4 between the upper and lower steel reinforcements 1, 2 under 
a strong electric current. 
The connection mode to the above mentioned electric power source is like 
this: the upper steel reinforcement 1 is connected to an electrode of the 
power source, while the steel reinforcement 2 is connected to the other 
electrode thereof. 
Principal gredients of the solder 31 include: 
______________________________________ 
(1) MnO 
3.4-38.0% 
(2) SiO.sub.2 
40.0-44.00% 
(3) MgO 
5-8% 
______________________________________ 
The solder 31 is in the form of red brown glassic grains having graininess 
of 8-40 meshes. 
An asbestos cloth or some other refractory material 32 is wrapped over or 
provided at the bottom of the solder tank 3 before it is filled with the 
solder 31, so that the latter is not to fall. 
b) Arcing process: as shown in FIG. 2, high temperature generated after 
striking of the electric arc 4 will melt the solder 31 placed near the 
arcing region, and an electroslag pool 311 will be formed, part of the 
solder 31 in the electroslag pool 311 will be evaporated under high 
temperature, the pressure in the vapor will generate a gas arc cavity 312 
near the arcing region, while the surrounding of the gas arc cavity 312 is 
adjacent to the layer of the molten elastic solder 313, the electric arc 4 
can steadily burn in the gas arc cavity 312 by the action of gas 
electrolizing. 
Function of the above mentioned arcing process is to generated high 
temperature to burn flat the ends of the steel reinforcements 1, 2 and to 
melt the solder 31 in the arcing region and form the electroslag pool 311 
and the gas arc cavity 312. 
Besides, function of the solder 31 is to raise the heat efficiency of the 
electric arc 4, and to chemically reduce the metal on the ends of the 
molten steel reinforcements 1, 2; yet the molten iron will not flow down 
by upholding action of the solder 31. 
Further, by function of the gas arc cavity 312, the electric arc 4 can 
steadily burn therein. 
c) Electroslag processing: as shown in FIG. 3, after completion of the 
above stated processes, the arc gas cavity 312 has formed an electroslag 
pool 311 of predetermined depth, now the front end of the upper steel 
reinforcement 1 is placed in the electroslag pool 311, and after the 
electric arc 4 is extinguished, the electroslag pool 311 in a molten state 
can still be electrically conductive, hence the welding loop remains to 
have electric current therein, the current will generate high temperature 
when it flows through the resistence of the electroslag pool 311, and 
temperature in the electroslag pool 311 can be maintained around 
2000.degree. C., meantime, the ends of the steel reinforcements 1, 2 are 
all uniformly heated in the electroslag pool 311 and continue to be 
molten, the front ends of the steel reinforcements 1, 2 are all uniformly 
burned flat by the electric arc 4, the front ends can therefore form a 
transitional layer of liquid state which is going toward solid state. 
d) Compressing process: as shown in FIG. 4, after completion of the above 
stated processes, a suitable pressure is applied onto the upper and lower 
steel reinforcements 1, 2 to render the ends thereof to be pressed to form 
a welding connection 10, meantime, impurities such as molten iron slag and 
oxides are extruded out of the connection to connect integratedly the 
upper and lower steel reinforcements 1, 2, such as shown in FIG. 5, to 
thereby ensure the structural strenth of the welding connection 10. 
Concerning the compressing signals as well as compressing time for the 
above stated compressing process, the welding time is set by a control 
circuit, while the compressing signals such as sounds or illumination 
emitted by the control circuit indicate it is the welding time for the 
operator to start the compressing step, and when the set compressing time 
is up, the control circuit will be turned off, and the whole welding 
process is completed. 
FIG. 8 shows the control circuit of the present invention, the components 
thereof are as follows: 
RD: NO-FUSE BREAKER, V: VOLTAGE GAUGE, 
X: INDICATING LAMP, M: ELECTROMAGNETIC SWITCH, 
M: NORMALLY OPENED CONNECTION OF THE ELECTROMAGNETIC SWITCH M, 
R1: RELAY, R2: RELAY, R3: RELAY, 
T: TIMING SWITCH, T1: CONTROL TRANSFORMER, 
T2: WELDING TRANSFORMER, : ELECTRIC CURRENT 
MUTUAL INDUCTANCE, BZ1, BZ2: BUZZERS, 
D1, D2: LIGHT EMITTING DIODES, 
G1, G2: BRIDGE TYPE RECTIFYING CIRCUITS, 
M1, M2: FUNCTIONALITY CONVERSION SWITCHES, 
S1a: NORMALLY OPENED CONNECTION OF PUSH BUTTON, 
S1b: NORMALLY CLOSED CONNECTION OF PUSH BUTTON, 
S2a: NORMALLY OPENED CONNECTION OF PUSH BUTTON, 
S2b: NORMALLY CLOSED CONNECTION OF PUSH BUTTON, 
Referring now to the circuit diagram of FIG. 8, the function and operation 
thereof are as follows: 
1. Under the normal welding situation (not the method of the present 
invention), a functionality conversion switch M1 is closed, voltage of 220 
V will directly connect to the electric magnetic switch M to render the 
later to operate, the normally opened connection M then is closed, the 
welding transformer is therefore turned on and operated, the welding work 
can be proceeded. 
2. Under the welding operation of the present invention: 
1) The switch M1 is in a normally opened position, push down the switch M2, 
the electric magnetic switch M is in an off state. 
2) When the preparing work is completed, push down the push button switch 
S1a (or S2a), the relay R2 (or R3) is turned on for operation, this in 
turn renders the relay R1 to be activated, now release the normally opened 
connection of the push button switch S1a (or S2a), the control circuit 
will automatically locked (self-maintaining), i.e., the nomally opened 
connections of the relays R2 ,R1 (or R3 ,R1) will be closed, the electric 
magnetic switch M and the timing switch T can be turned on and activated, 
the welding transformer then is turned on, and the welding process of the 
present invention is now started, after a predetermined time period, the 
normally opened connection of the timing switch T is closed, so that the 
buzzer BZ1 (or BZ2) and the lighty emitting diode D1 (or D2) are 
activated, then a sound, an optical signal are emitted to tell that it is 
the welding time, at this moment, the steel reinforcements 1, 2 are under 
compressing process and push down the normally closed connection of the 
push button switch S1b (or S2b), and the relay R2 (or R3) is turned off, 
then the relay R1 is in turn turned off, the same is the electric magnetic 
switch M, the welding transformer then stops operating. 
3) After the normally opened connection of the push button switch S1a (or 
S2a) is pushed down, if now the other normally opened connection of the 
push button switch S2a (or S1a) is also pushed down, the control system 
will not be in operation, this forms a protection by mutual locking to 
avoid over loading of the welding transformer T2. 
4) Two set of welding connections are used in the present invention, 
wherein two control circuit portions are alternatively utilized, i.e., 
when one of the welding connection sets completes its welding, the other 
set is ready for welding process, this alternative utilization can 
increase working effect. 
Moreover, after compressing process, the welding connections are kept in 
the solder for a few minutes, and then the solder tank is removed to spill 
the unmelted solder, after complete cooling down of the welding 
connections, a slag shell 314 is knocked away, and the whole operation is 
completed. 
Time for practising such welding method is 20-40 seconds, efficiency 
thereof is over fivefold higher than the prior arts (bind welding, 
interweave welding or bind weldrod welding). In the present invention, a 
clamping device is necessary for clamping steel reinforcements so that 
welding of the present invention can be performed. 
The clamping device for connecting steel reinforcements by welding of the 
present invention (as shown in FIG. 6) comprises mainly: a main body 5 
which is provided with a handle 51 on the top end thereof, and with two 
bars 52 functioning as a track extending at the lower portion thereof, a 
bolt 53 is appropriately provided equidistantly between the two bars 52, 
the bolt 53 has a driven bevel gear 531 in the interior of the main body 
5, the main body 5 has a crank 54 provided appropriately at one side 
thereof, the crank 54 has a driving bevel gear 541 in the interior of the 
main body 5, the driving bevel gear 541 engages with the driven bevel gear 
531 for rotation by gear transmission. 
Further, there is a sliding chuck 6 provided between the two bars 52, 
whereas the sliding chuck 6 can slide on the two bars 52 by means of two 
sliding sleeves 61, in the middle of the sliding chuck 6 there is provided 
appropriately a sleeve nut 62 which can be threadedly engaged with the 
bolt 53 of the main body 5. When the bolt 53 is rotated, the sleeve nut 62 
can move upwardly and downwardly, yet there is a sliding channel 63 on the 
upper end of and a movable clamping seat 64 at the front end of the 
sliding chuck 6, the movable clamping seat 64 is received in the sliding 
channel 63 by means of a threaded block 641 provided at the rear thereof 
(such as shown in FIG. 7), the sliding chuck 6 further has at the rear of 
the sliding channel 63 a bolt 65 functioning as a handle which has a 
threaded section 651 at the front end thereof for engaging with the 
threaded block 641 of the movable clamping seat 64. When the bolt handle 
65 rotates forwardly or backwardly by means of a hand controlled lever 
652, the threaded block 641 will render the movable clamping seat 64 to 
clamp or release the reinforcements. Wherein the chuck 6 can suit steel 
reinforcements of various sizes. 
Besides, as shown in FIG. 6, a fixed chuck 7 is provided at the lower end 
of the two bars 52 of the main body 5, while a sliding channel 71 is 
provided at the upper end of the fixed chuck 7, whereon and on the front 
end thereof, another movable clamping seat 72 is provided. The movable 
clamping seat 72 is received in the sliding channel 71 by means of a 
threaded block 721 provided at the rear thereof, the fixed chuck 7 further 
has at the rear of the sliding channel 71 a bolt 73 functioning as a 
handle which has a threaded section 731 at the front end thereof for 
engaging with the When the bolt handle 73 rotates forwardly or backwardly 
by means of a hand controlled lever 732, the threaded block 721 will 
render the movable clamping seat 72 to clamp or release the steel 
reinforcements. threaded block 721 of the movable clamping seat 72. 
With the above stated clamping device, the sliding chuck 6 is rotated for 
adjusting by means of the bolt handle 65 to enhance the movable clamping 
seat 64 to clamp the upper steel reinforcement 1; then the fixed chuck 7 
is rotated for adjusting by means of the bolt handle 73 to enhance the 
movable clamping seat 72 to clamp the lower steel reinforcement 2; 
whereby, in the welding process of the steel reinforcements, the crank 54 
provided at one side of the main body 5 can be optionally rotated 
forwardly or backwardly to make the driving bevel gear 541 drive the 
driven bevel gear 531 for rotation by gear transmission, meanwhile, the 
bolt 53 rotates and in turn drives the sliding chuck 6 to move upwardly 
and downwardly, the upper steel reinforcement 1 can thereby be raised in 
the process of arc striking or lowered into the electroslag pool in the 
process of electroslag processing, or the upper and the lower steel 
reinforcements 1, 2 are compressed for combination in the process of 
compressing etc. 
In conclusion, we can have the advantages of the present invention as 
listed below: 
1) Welding time is short, circa 20-40 seconds. 
2) Efficiency is high, it is over fivefold higher than that of a 
traditional practising. 
3) Cost is low, it is 1/3-1/8 of the traditional method. 
4) The whole welding process can be proceeded without arc lecht, fly ash, 
smoke or dust, the working environment is excellent. 
5) Operation is convenient, and is simple for learning, requirement of 
skill to workmen is lowered. 
6) Processing is expedient and very quick. 
Although this invention has been disclosed and illustrated with reference 
to particular embodiments, the principles involved are susceptible for use 
in numerous other embodiments which will be apparent to persons skilled in 
the art.