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

Le sezioni in acciaio possono essere fissate mediante rivetti, bulloni o saldatura.
Un rivetto è un dispositivo di fissaggio in acciaio con un albero cilindrico e una testa appositamente sagomata.
Il rivetto viene riscaldato al calore bianco in una fucina, inserito caldo attraverso i fori degli elementi di giunzione, e poi modellato con un martello pneumatico per formare una seconda testa opposta alla prima
In genere, i bulloni vengono inseriti in fori più larghi di un sedicesimo di pollice rispetto al diametro del bullone. Le rondelle in acciaio temprato sono spesso posizionate sotto una o entrambe le estremità del bullone prima che il dado venga avvitato.
I bulloni sono in genere serrati con un avvitatore a impulsi pneumatico o elettrico.
Nella saldatura, si crea un potenziale elettrico tra i pezzi di acciaio destinati alla giunzione e un elettrodo metallico.
Quando l'elettrodo è posizionato vicino alla giuntura degli elementi in acciaio, forma un arco elettrico continuo che fonde un'area specifica sia degli elementi in acciaio che della punta dell'elettrodo, creando una pozzanghera fusa
L'elettrodo viene gradualmente spostato lungo la cucitura, depositando una perlina continua di metallo che si solidifica, formando una connessione senza soluzione di continuità tra i pezzi di acciaio.

tecniche di fissaggio in acciaio

Le sezioni in acciaio possono essere unite tra loro tramite varie tecniche di fissaggio, tra cui rivettatura, bullonatura e saldatura, ciascuna adatta a diverse condizioni e requisiti strutturali.

I rivetti sono elementi di fissaggio cilindrici in acciaio con una testa appositamente progettata. Durante l'applicazione, i rivetti vengono riscaldati fino a diventare incandescenti e quindi inseriti attraverso fori, realizzati in precedenza, nelle sezioni in acciaio. Viene utilizzato un martello pneumatico per modellare l'estremità esposta in una seconda testa, fissando insieme le sezioni.

L'imbullonatura è un altro metodo di fissaggio comune in cui i bulloni vengono inseriti in fori leggermente più grandi del diametro del bullone, in genere di un 1,59 millimetri. Rondelle in acciaio temprato vengono spesso posizionate sotto le teste dei bulloni o i dadi per distribuire il carico ed evitare danni all'acciaio. I bulloni vengono serrati utilizzando chiavi a percussione pneumatiche o elettriche per garantire una tenuta sicura.

La saldatura crea un legame forte e senza soluzione di continuità fondendo i pezzi di acciaio nel punto di contatto. Viene generato un arco elettrico tra un elettrodo metallico e le sezioni in acciaio. Questo arco fonde la punta dell'elettrodo e le superfici di acciaio adiacenti, formando una pozza fusa. L'elettrodo viene progressivamente spostato lungo la giunzione, depositando metallo fuso che si solidifica per formare una giunzione continua e durevole.

Queste tecniche forniscono soluzioni robuste per l'assemblaggio di strutture in acciaio, ciascuna delle quali offre diversi vantaggi in termini di resistenza, efficienza e idoneità all'applicazione.

Le sezioni in acciaio possono essere fissate mediante rivetti, bulloni o saldatura.
Un rivetto è un dispositivo di fissaggio in acciaio con un albero cilindrico e una testa appositamente sagomata.
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Civil Engineering

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Masonry Materials

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KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

civil engineering

How Steel Sections Are Joined

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