Custom Weldments

Heavy Custom Weldments & Assemblies

Custom weldments form the structural backbone of the world's heaviest machinery. From massive industrial press frames to offshore drilling equipment, these assemblies demand extreme structural integrity, deep weld penetration, and flawless dimensional accuracy.

At Openex, we possess the crane capacity (up to 250 tons), the floor space (180 acres), and the highly skilled AWS/ASME certified workforce required to fabricate colossal welded assemblies. We offer a true turnkey solution: cutting thick plates, executing heavy multi-pass welds, performing thermal stress relief, and finishing with precision post-weld CNC machining.

Weldment Manufacturing Specifications

We build complex heavy weldments to your exact blueprints. Below are our general facility capacities and standards:

Maximum Weight Up to 250 Tons (Single Assembly)
Welding Processes SAW (Submerged Arc), FCAW, GMAW (MIG), GTAW (TIG), SMAW
Materials Processed Carbon Steel (A36, Q345, S355), Stainless Steel, HSLA Steels, Aluminum, Wear-Resistant Alloys.
Post-Weld Processing Thermal Stress Relief (PWHT), 5-Axis CNC Machining, Boring, Planer Milling.
Certifications & NDT AWS D1.1, ASME Section IX, ISO 3834. Testing: UT, MT, PT, RT (X-Ray).

Our Work: Heavy Weldments

Massive Structural Steel Weldment Fabrication
Complex Heavy Structural Weldment
Post-Weld CNC Machined Machine Bed
Machined Welded Base Frame

The Turnkey Weldment Process

1
Material Prep & Beveling

Heavy plates are profile-cut using high-def plasma and oxy-fuel. Edges are precisely beveled using CNC machining or specialized bevellers to prepare for deep weld penetration.

2
Fit-Up & Heavy Welding

Components are tacked and welded utilizing massive positioners and rotators. We deploy multi-pass SAW and heavy-deposition FCAW to ensure flawless joints on extremely thick plates.

3
Thermal Stress Relief (PWHT)

Heavy welding introduces intense internal stress. We utilize our massive on-site heat treatment furnaces to relieve stress, preventing distortion and ensuring long-term dimensional stability.

4
Post-Weld CNC Machining

Finally, the weldment is moved to our large-scale gantry mills and boring machines, where mounting pads, bearing housings, and mating surfaces are machined to micron-level tolerances.