Metal fusion bonding – With means to handle work or product – Including means to orient work or position work portion...
Patent
1986-11-14
1987-12-15
Jordan, M.
Metal fusion bonding
With means to handle work or product
Including means to orient work or position work portion...
228219, 269 481, 279 2R, B23K 3106
Patent
active
047127201
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION OF THE INVENTION
The invention relates to a device for mutually centering and clamping two workpieces which are to be welded to one another and have a round bore, which device, for each of the workpieces, has a clamping unit on both sides of a welding area provided with an inert gas supply, which clamping unit has at least one peripheral row of clamping members which are contained in a clamping groove, can be stretched outwards or relaxed inwards radially by mutual axial approach or distancing of the flanks of the clamping groove and have an outwardly pointing clamping surface for the contact with the bore surface of the workpiece and are also at a distance from one another in the peripheral direction.
In a known device of this type (DE-A No. 2,708,040), each of the clamping grooves contains a pluratity of specially formed clamping wedges which in turn support a clamping shoe on their outer surface facing towards the pipe periphery, which clamping shoe can come in contact over a large area with the pipe inner surface to be clamped The clamping wedges are held inside the clamping grooves by means of a number of tension springs running in the peripheral direction. The clamping grooves are formed on the one hand by a firmly arranged groove wall and on the other hand by a hydraulic piston which, for tightening the clamping wedges by charging with a pressure medium, can be axially displaced relative to the groove wall. Although the known clamping device is intended for a laser welding process and the clamping shoes are therefore comparatively safe from damage with regard to their stressing caused by the clamping forces and the thermal loading, the clamping wedges and clamping shoes of the known device are of a fairly coarse embodiment. Although this has the disadvantage that the entire construction turns out to be relatively heavy, it is also partly considered advantageous because it facilitates the heat dissipation ("Automation" 1977, p 59), with it also being possible for this purpose to provide the clamping shoes with special cooling channels (U.S. Pat. No. 4,387,845). A further disadvantage of the embodiment of the clamping shoes as large parts is that they make it difficult to evacuate completely the atmospheric air by the inert gas supplied to the welding area. In the known devices, the intention is to achieve such an accurately centered guidance of the clamping members that the latter can cylindrically orientate a deformed pipe surface. However, the smaller the number of clamping members, the more limited are the possibilities of an accurately centered movement guidance.
The object of the invention is to create a clamping device of the type mentioned at the beginning which is of simple construction and can be variably and reliably applied, with the intention being to ensure adequate cooling and, at moderate inert gas consumption, reliable oxygen displacement.
The solution according to the invention is that the axial extent of the clamping members, lined up in large number at a slight mutual distance, is greater than the width of their clamping surfaces in the peripheral direction.
As a departure from the previous design principles, the individual clamping members are not made as large parts in small number but conversely as small parts in large number. Since they only extend slightly in the peripheral direction and in particular since their contact surface with the pipe inner surface is small in the peripheral direction, the disturbing influences which are brought to bear on them on the one hand from the welding area and on the other hand as thermal stress from the pipe inner surface ae also kept small in comparison with the cooling effect of the inert gas, which cooling effect is therefore very intensive, because the axial extent of the clamping members is comparatively large and therefore a large cooling surface is made available. During the displacement of the atmospheric oxygen by the inert gas, the small clamping members do not act as barriers but in their plurality, in combination with
REFERENCES:
patent: 2226078 (1940-12-01), Spahn
patent: 2546950 (1951-03-01), Nixon
patent: 3026115 (1962-03-01), Brauer et al.
patent: 3095844 (1963-07-01), Thielsch
patent: 3498518 (1970-03-01), Wheeler et al.
patent: 3900913 (1975-08-01), Drumm
patent: 4387845 (1983-06-01), Mefferd
patent: 4413655 (1983-11-01), Brown
patent: 4415114 (1983-11-01), Hallenbeck
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