Name: how steel sections are joined
Uploaded: 2024-09-12T16:16:25.000Z
Duration: 1 min 17 s
Channel: JoVE

As seções de aço podem ser fixadas usando rebites, parafusos ou soldagem.
Um rebite é um fixador de aço com um eixo cilíndrico e uma cabeça de formato especial.
O rebite é aquecido ao calor branco em uma forja, inserido enquanto quente através dos orifícios nos membros de união e, em seguida, moldado com um martelo pneumático para formar uma segunda cabeça oposta à primeira
Normalmente, os parafusos são colocados em orifícios que são uma décima sexta polegada mais largos que o diâmetro do parafuso. Arruelas de aço temperado são frequentemente colocadas sob uma ou ambas as extremidades do parafuso antes que a porca seja aparafusada.
Os parafusos são normalmente apertados com uma chave de impacto pneumática ou elétrica.
Na soldagem, é criado um potencial elétrico entre as peças de aço destinadas à união e um eletrodo de metal.
Quando o eletrodo é posicionado próximo à costura dos membros de aço, ele forma um arco elétrico contínuo que derrete uma área específica dos membros de aço e da ponta do eletrodo, criando uma poça derretida
O eletrodo é gradualmente movido ao longo da costura, depositando um cordão contínuo de metal que se solidifica, formando uma conexão perfeita entre as peças de aço.

técnicas de fixação de aço

Seções de aço podem ser unidas por meio de várias técnicas de fixação, incluindo rebitagem, aparafusamento e soldagem, cada uma adequada para diferentes requisitos e condições estruturais.

Rebites são fixadores cilíndricos de aço com uma cabeça especialmente projetada. Durante a aplicação, os rebites são aquecidos até ficarem incandescentes e, em seguida, inseridos em furos pré-perfurados nas seções de aço. Um martelo pneumático é usado para moldar a extremidade exposta em uma segunda cabeça, prendendo as seções juntas.

Aparafusamento é outro método comum de fixação em que os parafusos são inseridos em furos ligeiramente maiores do que o diâmetro do parafuso, normalmente em 1,59 milímetros. Arruelas de aço temperado são frequentemente colocadas sob as cabeças dos parafusos ou porcas para distribuir a carga e evitar danos ao aço. Os parafusos são apertados usando chaves de impacto pneumáticas ou elétricas para garantir um encaixe seguro.

A soldagem cria uma ligação forte e uniforme ao derreter as peças de aço no ponto de contato. Um arco elétrico é gerado entre um eletrodo de metal e as seções de aço. Este arco derrete a ponta do eletrodo e as superfícies de aço adjacentes, formando uma poça derretida. O eletrodo é progressivamente movido ao longo da costura, depositando metal derretido que se solidifica para formar uma junta contínua e durável.

Essas técnicas fornecem soluções robustas para a montagem de estruturas de aço, cada uma oferecendo diferentes benefícios em termos de resistência, eficiência e adequação à aplicação.

Técnicas de fixação de aço

As seções de aço podem ser fixadas usando rebites, parafusos ou soldagem.
Um rebite é um fixador de aço com um eixo cilíndrico e uma cabeça de formato especial.
O...

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Steel Fastening Techniques

how steel sections are joined

Steel sections are joined with rivets, bolts, or welding. Each method fits different structural needs and working conditions. These fastening techniques help assemble strong steel structures in practical ways.

Riveting uses cylindrical steel fasteners with a specially designed head. The rivets are heated until white-hot and then placed through pre-drilled holes in the steel sections. A pneumatic hammer shapes the exposed end into a second head, which locks the pieces together.

Bolting is another common method for joining steel. The bolt holes are slightly larger than the bolt diameter, usually by one-sixteenth inch. Hardened steel washers are often placed under the bolt heads or nuts to spread the load and reduce damage to the steel. The bolts are then tightened with pneumatic or electric impact wrenches for a secure fit.

Welding creates a strong, seamless joint by melting the steel at the contact point. An electric arc forms between a metal electrode and the steel sections. The arc melts the electrode tip and the nearby steel surfaces, creating a molten puddle. As the electrode moves along the seam, it deposits molten metal that solidifies into a continuous, durable bond.

How Steel Sections Are Joined

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Steel sections are joined with rivets, bolts, or welding. Each method fits different structural needs and working conditions. These fastening techniques help assemble strong steel structures in practical ways. Riveting uses cylindrical steel fasteners with a specially designed head. The rivets are heated until white-hot and then placed through pre-drilled holes in the steel sections. A pneumatic hammer shapes the exposed end into a second head, which locks the pieces together. Bolting is...

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key terms and concepts

Learn how steel sections are joined by riveting, bolting, and welding. See how each method works and why builders choose different fastening techniques.

How Steel Sections Are Joined | JoVE K12

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civil engineering

How Steel Sections Are Joined

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