Several options are available for notching and piercing of tubing. This article covers the following fabrication methods: notching of 90-degree structural joints, angular joints, and flow-through joints; side notching; nonmandrel piercing; arbor (supported) piercing; and arbor slotting.
Structural Joint Notching
Structural 90-degree joints can be produced in many ways, depending on the number of pieces required. The operator can mill or grind the tube end, use a hole saw to produce the required form, or notch the tube with a notching tool.
The tube is notched only to the inside diameter (ID) of the tube, leaving the wall thickness flat on the tube end. This style of notch is suited for shielded metal arc welding (SMAW) applications.
This style of tooling generally is a spring-loaded, self-contained, spanker-style unit. Typically, this unit can be used in a hand press, air press, mechanical press, ironworker, press brake, air/oil cage unit, or hydraulic cage unit. The tooling cuts from inside the tube downward over a die edge, producing a clean, undistored notch in one wall of the tube per press stroke. Two press strokes are required per completed tube end.
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