keevitamise tehnika mille käigus kontsentreeritud soojusallikas tungib läbi tooriku, moodustades erilise kujuga ava keevisvanni juhtserval (vt läbistav keevitus), welding technique in which concentrated heat source penetrates through a workpiece, forming a hole (keyhole) at the leading edge of the weld pool (see: keyhole welding)