JPS6025344Y2 - Clamp device for gas pressure welding - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a clamping device for gripping steel pipes to be welded under gas pressure, large-diameter reinforcing bars, etc. in steel pipe piping work, large-diameter reinforcing bar construction, etc.

Conventionally, as shown in FIGS. 1 and 2, steel pipe gas welding equipment has a steel pipe 12 to be welded with gas on both sides of an oscillating unit 11 equipped with a burner 10 that can be freely rotated.
Support rods 15 are arranged with clamping devices 13, 14 to grip the steel pipe 12 and are arranged parallel thereto on both sides of the steel pipe 12.
The middle part of each support rod 15 is passed through the support arm 16 fixed to the oscillating unit 11, and one end of each support rod 15 is passed through and fixed to one of the clamp devices 13.
The other end is passed through the other clamp device 14, and
A structure in which a pressurizing hydraulic cylinder 17 is attached to the end of a support rod 15 protruding from the clamp device 14 is known.

The clamp devices 13 and 14 used in the steel pipe gas pressure welding device include (1) arms 2 and 6 on both sides of the main clamp piece 1 and arms 4 on both sides of the auxiliary clamp piece 3, as shown in FIG. , 7 and the bolt 1 inserted across them.
8 and a type that is tightened and connected with nuts 19, (
2) As shown in FIG. 4, one arm 2 of the main clamp piece 1
and one arm 4 of the auxiliary clamp piece 3 are pivotally connected by a pivot 20, and the main clamp piece 1, the other arm 6, the other arm 7 of the auxiliary clamp piece 3, and a tightening hydraulic jack 8 superposed thereon. There is a known type in which an annular tightening frame 9 is provided with a tightening ring.

However, in the case of the clamp device of the above formula (1),
The clamping operation takes a relatively long time, and adjusting the tightening force of the bolts and nuts on both sides requires skill, and when tightening the bolts and nuts manually, a considerably large tightening torque is required. There is a problem in that the clamp acts as a shearing force and loosens the bolt/nut, making the clamp susceptible to slicing.

In addition, in the case of the clamping device of the type (2) above, the machining of the pivot joint is complicated and the manufacturing cost is high.If the manufacturing precision of the pivot joint is increased, there will be no backlash in the clamp device, making it easier to tighten steel pipes. The contact surface becomes less compliant with deformation, making it more likely to slip.

Furthermore, if the manufacturing precision of the pivot joint is low, there is a problem that it is likely to loosen against the pressure welding force of the steel pipes and slip.

The object of this invention is to provide a gas pressure welding clamp device that advantageously solves the above-mentioned problems.

Next, this invention will be explained in detail using illustrated examples.

5 and 6 show a gas pressure welding clamp device according to an embodiment of the invention, in which the opening of the groove-shaped portion 21 of the main clamp piece 1 and the groove-shaped portion 22 of the auxiliary clamp piece 3 are shown.
are arranged so that the openings of the main clamp pieces 1 and
One arm 2 of the main clamp piece 1 and one arm 4 of the auxiliary clamp piece 3 are inserted into the connecting annular frame 5, and the other arm 6 of the main clamp piece 1 and the auxiliary clamp piece 3 placed between them The other arm 7 and the tightening hydraulic jack 8 are connected to the tightening annular frame 9.
located within.

According to this invention, one arm 2 of the main clamp piece 1 and one arm 4 of the auxiliary clamp piece 3 are inserted into the connecting annular frame 5, and the other arm 6 of the main clamp piece 1 and the auxiliary clamp Since the other arm 7 of the piece 3 and the tightening hydraulic jack 8 are inserted into the annular tightening frame 9, the clamping device can be attached and detached from steel pipes and large-diameter reinforcing bars by attaching and detaching the annular frames 5 and 9. It can be done easily and quickly, and furthermore, the manufacturing cost is reduced because the processing to be performed on the connecting annular frame 5, one arm 2 of the main clamp 1 inserted therein, and one arm 4 of the auxiliary clamp 3 is simple. It is inexpensive, and since the wall thickness of each clamp piece can be reduced, the weight can be reduced.Also, since there is a degree of freedom in the connection part of each clamp piece, there is no damage to the clamping deformation of steel pipes, etc. when clamping them. The surfaces have good conformability, which prevents slippage, and even if axial welding force is applied from steel pipes or large diameter reinforcing bars, this is supported by the spigot and each annular frame 5, 9. Since each clamp piece does not slip, and each annular frame 5, 9 presses the clamp piece and its gold thread, effects such as less looseness and less slippage can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a steel pipe gas pressure welding device, and FIG. 2 is a side view thereof. 3 and 4 are front views showing a conventional gas pressure welding clamp device. FIG. 5 is a plan view of a gas pressure welding clamp device according to an embodiment of the invention, and FIG. 6 is a longitudinal sectional front view of a portion thereof. In the figure, 1 is a main clamp piece, 2 is an arm, 3 is an auxiliary clamp piece, 4 is an arm, 5 is an annular frame for connection, 6 and 7 are arms,
8 is a hydraulic cylinder for tightening, 9 is an annular frame for tightening, 10 is a burner, 11 is an oscillating unit, 12 is a steel pipe, 13 and 14 are clamp devices, and 21 and 22 are groove-shaped portions.

Claims (1)

[Scope of utility model registration request] One arm 2 of the main clamp piece 1 and one arm 4 of the auxiliary clamp piece 3 are inserted into the connecting annular frame 5, and the other arm 6 of the main clamp piece 1 and the other arm 7 of the auxiliary clamp piece 3 are inserted. The clamp device for gas pressure welding is characterized in that the clamping hydraulic cylinder 8 and the clamping hydraulic cylinder 8 are inserted into the clamping annular frame 9 in a mutually overlapping state.