Key Takeaways
- Plate Tolerance ±0.5mm: Thickness variation affects weld quality.
- Circularity ±D/5000: Diameter tolerance prevents stress concentrations.
- SAW for Longitudinal Seams: Submerged arc welding provides consistent quality.
- 100% Visual Inspection: All welds visually inspected minimum.
- UT on 10% of Welds: Ultrasonic testing for internal defects.
Table of Contents
Assembly Quality Affects Everything
On a project in Saudi Arabia, we rejected a batch of shell plates because thickness variation exceeded ±0.5mm. The supplier protested, but our quality control prevented potential welding defects that could have caused field failures. Precision in plate preparation ensures structural integrity.
Plate Preparation
Material inspection for surface defects and thickness tolerance. Edge beveling to 30-35° with 1.5-2.0mm root face. Clean bevel surfaces to bright metal.
Shell Assembly
Position plates with crane support. Align vertical joints with 2-3mm root gap. Check diameter at each course (tolerance: ±D/5000 or ±10mm). Tack welds minimum 50mm long at 300mm spacing.
Welding Procedures
Longitudinal seams first using SAW or GMAW. Back-gouge from root side for full penetration. Circumferential seams after longitudinal completion. Interpass temperature maximum 250°C.
Frequently Asked Questions
Q: How long does shell assembly take?
A: For a typical 3,000-ton silo: 2-4 weeks depending on crew size and weather conditions.
Need shell assembly supervision? Manxing provides experienced installation teams. Request Installation Quote