Soyer BMS-9 Operating Instructions Manual page 31

Installing non-adjustable stud chucks
Step 4: Undo the union nut.
Step 5: If there is still a stud chuck in the gun, remove it.
Step 6: Slide the stud chuck up to the stop into
the spring piston of the gun.
Step 7: Hand-tighten the union nut.
Step 8: Plug the support tube onto the gun.
The assembly is complete.
Operating instructions Soyer Bolzenschweißtechnik 31