How are cranes designed?

A concrete foundation is prepared so that the crane will be safely anchored to the ground and stable during lifting. A mobile crane assembles the tower crane, lifting several segments of tower into place along with core components. The tower crane builds the rest of its own structure as it rises to its ultimate height.

What is bolted joint analysis?

The bolted joint works by inducing an initial clamping force (“preload”) on the joint by threading the fastener into either a nut or into threads that have been tapped into one of the parts. …

What materials are needed to build a crane?

The most important substance used to manufacture cranes is steel. Steel is an alloy of iron and a small amount of carbon. For structures that do not require very high strength, a common form of steel known as carbon steel is used.

Which are the applications of bolted joints?

Clamped bolted joints are often used on pipe flanges, automotive engines and chemical reactors. In all of these applications, the bolted joint has three mechanical components: the flange parts, the fasteners (bolts and nuts), and the seals or gaskets.

What kind of structure is a crane?

Tower cranes and communication towers are examples of frame structures. Frames are made from bars joined together to form a ‘framework’. This is one of the most economical ways of building structures. Some modern buildings have a frame structure which can only be seen during construction.

What are bolted joints used for?

The most common kinds are threaded fasteners (bolts and screws) and riveted joints. These joints are primarily used to provide continuity of structure and transfer of internal load from one member to another.

Where are bolted joints used?

Which material is used for crane hook?

Some common materials used to make the crane hook are Carbon steel, Alloy steels, Wrought iron, HSLA (High Speed Low Alloy), Chromium steel, Stainless steel and Gray cast iron [3, 6].

What is preload in bolted joint?

Preload is the tension created in a fastener when it is tightened. This tensile force in the bolt creates a compressive force in the bolted joint known as clamp force. For practical purposes, the clamp force in an unloaded bolted joint is assumed to be equal and opposite of the preload.

What type of guidance is provided for bolted joint design?

Guidance is provided for general bolted joint design, computation of preload uncertainty and preload loss, and the calculation of the bolted joint factor of safety. Axial loads, shear loads, thermal loads, and thread tear out are used in factor of safety calculations. Additionally, limited guidance is provided for fatigue considerations.

What is the key to good Crane girder performance?

Proper detailing is the key to good fatigue performance The vast majority of crane girder performance issues occur at the crane girder to column connection. 3 4 Column or Bracket Support

What are the different types of loads for bolted joints?

Loads can be applied to bolted joints in a number of different ways, each of which produces unique effects on the joint. These effects result from the way the joint is loaded, as well as how the joint responds to the load. Some of the various load types include tensile, shear and bending.

What happens if a bolt has too little clamping force?

With too little clamping force, the joint may loosen. If the joint is exposed to cyclical loads, too little clamping force can shorten the bolt’s fatigue life. Too much clamping force can also cause severe problems.