How to design a helical compression spring

Helical spring is a vital element for many machines and most of the time helical compression spring is used rather than helical tension spring. This article will talk specifically about design of helical compression spring. More over, we will not Read the rest

How to draw free body diagram

Using free body diagram (FBD) is a method for analyzing and simplifying different forces applied on a member or body. Most of the practical cases you will come across for force analysis are complex in nature. When you will try … Read the rest

Force analysis of truss

You are a structural design engineer and you are in task of designing a truss, the first thing you have to do is analysis of truss to find out the force applied at different joints and members of the truss.… Read the rest

Difference between frame and truss

Many times in our daily engineering work life the words truss and frame are used in place of each other, though they have many similarities but there exist some differences between truss and frame.

Truss and frame both are constructed … Read the rest

How to create and use Mohr’s circle Diagram

Mohr’s circle is an important tool used for visualizing relations between normal stresses, maximum principal stresses, shear stresses and maximum shear stresses. Mohr circle diagram was developed by Christian Otto Mohr and it is used widely even now. We will Read the rest

Difference between Ductile and brittle materials

The materials which elongates more than 5% before fracture is called ductile material otherwise brittle materials. Gold, silver, copper are typical example ductile materials and cast iron, concrete are brittle materials.

In failure theories yield strength is used for ductile Read the rest

Theories of failure for brittle materials (part-3): Maximum principal stress theory

Maximum principal stress theory is useful for brittle materials. Maximum principal stress theory or maximum principal stress criterion states that failure will occur when maximum principal stress developed in a body exceeds uniaxial ultimate tensile/compressive strength (or yield strength) of Read the rest

How to find principal stress and principal plane of a complex stress system?

The complication of a stress system increases with increase of number of applied multi directional normal and shear stress. One very interesting and important fact about the complex stress system is that most of the time there will be one … Read the rest

Theories of failure for ductile materials (part-2): Von Mises Criterion

This theory also known as maximum distortion energy theory, shear strain energy theory or octahedral shear stress theory.

The detail study shows that it is the shear strain energy rather than shear stress which is the main culprit behind yielding Read the rest

Theories of failure for ductile materials (part-1): maximum shear stress criterion

There are a set of criterion on the basis of which we can predict the failure load/loads require for a certain component. It is comparatively easy to compute failure stress if the component under your design consideration is subjected to Read the rest