The welding seam can have any desired shape, as long as it exhibits a sufficient length and strength, in order to ensure {HEAD ~ a permanent joining} of {TAIL ~ the sheets} 
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The welding seam can have any desired shape , as long as it exhibits a sufficient length and strength , in order to ensure { HEAD ~ a permanent joining } of { TAIL ~ the sheets }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL