﻿GET_GEVOMechL2_01_01_01_04 - ANIMATION Screen
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Strength is an important consideration when applying a bolt.

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Bolt material strength is determined by the alloy and the processing methods, such as cold working and heat treating.

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The two important material properties are yield strength and tensile strength.

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Yield strength is the stress level at which the material yields or permanently deforms.

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Tensile strength, sometimes called ultimate strength, is the stress level at which the material breaks.

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The tensile strength is always higher than the yield strength.

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Materials with a large difference between the yield and tensile strength are considered ductile, meaning they will stretch substantially before breaking.

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For inch-size fasteners, the material strength is specified by the "grade".

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A grade 8 bolt is stronger than a grade 5, which is stronger than a grade 2.

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The grade is indicated by a series of marks on the bolt head.

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For metric fasteners, the term "property class" is used and is stamped directly on the head.

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When you replace a bolt, it is important to identify its grade correctly.

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If bolts are not replaced with the same grade, a failure can occur that could endanger lives and equipment.


