IS 6533:2000 (Part 1) is the Indian Standard (BIS) for design and construction of steel chimneys, part 1: mechanical aspects. This Indian Standard (Part 1) provides guidelines for the mechanical aspects of designing and constructing steel chimneys. It covers selection of materials, determination of shell plate thickness, corrosion allowance, design of openings, and requirements for appurtenances like ladders, platforms, and lightning protection.
Code of practice for design and construction of steel chimneys, Part 1: Mechanical aspects
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Minimum Shell Thickness (Carbon Steel) | 6 mm for shell plate, 8 mm for base plate | 1/4 inch (6.35 mm) for shells 3 ft diameter or greater | ASME STS-1-2011 |
| Minimum Corrosion Allowance (Exterior, Painted) | 1.5 mm | Typically 1/16 inch (1.6 mm) for mild environments | ASME STS-1-2011 |
| Maximum Allowable Deflection (Top) | H/200 (where H is chimney height) | H/200 for unlined stacks, H/100 may be acceptable depending on conditions | ASME STS-1-2011 |
| Basic Allowable Bending Stress | 0.66 * Fy (where Fy is yield stress), as per IS 800:1984 which IS 6533 refers to | 0.60 * Fy for tension and compression on extreme fibers | ASME STS-1-2011 |
| Aerodynamic Shape Factor (Cf for circular section) | 0.7 (as per referred IS 875 Part 3) | 0.5 to 0.8 depending on Reynolds number and surface roughness | EN 1991-1-4 |
| Minimum Anchor Bolt Diameter | 20 mm | 1 inch (25.4 mm) | ASME STS-1-2011 |
| Stiffener Outstand to Thickness Ratio (Max) | 16 (for elements under compression) | 12 (for unstiffened elements under compression) | ASME STS-1-2011 |