True 4-way cross pieces are uncommon. We removed and bevelled one made of creep-resistant X20 steel, 61.5 mm wall thickness, in 36 hours.
In piping, cross pieces — single-piece four-way branches — are a rarity. Three-way tees are in every code; four-way branches are usually fabricated from two individual tees. When a real cross piece is installed, there are typically structural or flow reasons — and it makes removal demanding.
The project
Material: X20CrMoV12-1, a classic creep-resistant Cr-Mo steel typical for high-temperature steam lines in power plants. Size: 521 × 61.5 mm (OD × wall thickness). Task: complete removal of the cross piece, all four sides bevelled with a defined weld preparation angle.
What makes X20 fussy
X20 is not a material you walk through with a torch. The high chromium and molybdenum content makes it sensitive to hardening and hydrogen-induced cracking under uncontrolled thermal input. Cutting means cold — i.e. mechanical.
Our solution
- Split-frame machine sized for OD > 500 mm.
- Multiple tool stations for parallel cutting and bevelling of the four sides.
- Reduced-feed parameters appropriate for the creep-resistant material.
- Continuous heat-input monitoring.
Result
36 hours total — from setup of the first cutting machine to sign-off of the fourth bevel. The cross piece was inspection-ready in the staging area, all weld preps angle- and surface-compliant.
This is bread-and-butter for a specialised on-site machining contractor: not a workshop substitute, but workshop quality where the part already sits.