Structural characteristics and application scenarios of rigid beams

A rigid beam is a supporting structure attached to the outer wall of a shell (such as a boiler drum, flue, or dust collector), fixed to the shell by welding or bolting, forming a "shell - rigid beam" composite structure to improve the overall resistance to deformation.

2. Structural Characteristics

Material: Mostly made of steel sections (such as angle steel, channel steel, I-beam) or welded steel plates, with high strength and rigidity.

Form:

Circumferential rigid beam: Arranged along the circumference of the equipment, mainly resisting hoop pressure and local deformation;

Axial rigid beam: Arranged along the axial direction (height direction) of the equipment, used to support vertical loads or enhance overall stability;

Grid-like rigid beam: Composed of circumferential and axial beams to form a grid structure, suitable for large-diameter or complex-shaped shells, providing all-round support.

Core Functions and Roles

1. Preventing Shell Instability

When the equipment is subjected to external pressure (such as negative pressure inside the boiler flue, external pressure on the pressure vessel), the shell may undergo "buckling instability" (such as local dents, wrinkles) due to insufficient rigidity. The rigid beam constrains the shell deformation and disperses the external pressure load to the beam body, avoiding instability.

2. Load Bearing and Transmission

Bears the weight of equipment accessories (such as pipelines, insulation layers, platforms), as well as external loads such as wind loads and seismic loads, and transmits the loads to the equipment support structure or foundation.

3. Maintaining Structural Shape

For large thin-walled shells (such as boiler furnaces, chimneys), rigid beams can maintain their geometric shape, preventing deformation caused by thermal expansion and contraction or pressure fluctuations, ensuring normal equipment operation.

Typical Application Scenarios

1. Boiler System

Furnace rigid beam: Arranged on the outside of the boiler water wall, resisting fluctuations in combustion pressure inside the furnace (such as explosion impact) and negative pressure suction, while also supporting the weight of the water wall tube group and insulation layer.

Flue rigid beam: Installed on the outer wall of the boiler flue, preventing the flue from collapsing due to negative pressure (induced draft fan suction), while also supporting the load of the heating surface inside the flue (such as economizer, air preheater).

2. Pressure Vessels and Tanks

Used for the cylindrical wall or head of large tanks (such as LNG tanks, oil tanks) to resist external atmospheric pressure or internal medium pressure fluctuations, especially when the top or bottom of the tank is subjected to local pressure, the rigid beam can enhance structural safety.

3. Industrial Pipelines and Chimneys

Large-diameter pipelines (such as steam pipelines, dust removal pipelines) or tall chimneys are supported by rigid beams to reduce vibration, resist wind loads, and prevent pipeline deformation or chimney collapse.