Stepped shear bolts

O processo de encabeçamento a frio é um dos novos processos para a maquinagem sob pressão com menos ou nenhum corte
metal. É um método de processamento que utiliza a deformação plástica do metal sob a ação de
forças externas e, com a ajuda de moldes, redistribui e transfere o volume de metal para formar
as peças ou os espaços em branco necessários. O processo de encabeçamento a frio é o mais adequado para a produção de
elementos de fixação, tais como cavilhas, parafusos, porcas, rebites, cavilhas, etc.

Stepped shear bolts are specialized fasteners designed to provide controlled shear failure under specific load conditions, often used in structural or mechanical applications where safety and predictable failure points are critical. Here’s a detailed description:

Key Features of Stepped Shear Bolts:

1. Stepped Shaft Design

   • The bolt has a reduced-diameter section (shear groove) along its shank, creating a deliberate weak point.

   • This step ensures the bolt shears at a predetermined load, protecting other components from damage.

2. Material & Strength

   • Typically made from high-strength steel (e.g., Grade 5, Grade 8, or alloy steel) to ensure consistent shear performance.

   • Heat-treated for precise shear strength.

3. Tipos de cabeça

   • Available in various heads (hex, socket, round) depending on application needs.

   • Some designs include a breakaway head that snaps off after proper installation torque.

4. Tipo de rosca

   • May feature full or partial threading, with the shear step located in the unthreaded portion to avoid thread distortion during shearing.

5. Shear Load Control

   • The stepped section is engineered to fail at a specific shear force, acting as a mechanical fuse.

   • Used in safety-critical systems (e.g., aircraft, machinery, structural joints) to prevent overload.

Aplicações:

• Structural Engineering: Shear-critical connections in steel frameworks.

• Aerospace: Shear pins in flight control systems.

• Automotive: Suspension or drivetrain components.

• Industrial Machinery: Overload protection in couplings or gearboxes.

Vantagens:

• Predictable Failure: Prevents catastrophic damage by shearing at a set load.

• Easy Replacement: Broken bolts can be quickly replaced post-failure.

• Corrosion Resistance: Often coated (e.g., zinc, cadmium) for durability.

Example Use Case:

In a wind turbine, stepped shear bolts may secure the blade hub. If excessive force occurs (e.g., storm winds), the bolts shear, protecting the rotor assembly from severe damage.