INTRODUCTION TO ALIGNMENT By Er.Laxman Singh Sankhla B.E.Mech., Chartered Engineer Jodhpur, India Mail ID:
[email protected] INTRODUCTION TO ALIGNMENT.
Alignment is the practice of placing two or more machines in such a relationship with each other that their shaft centrelines of the different units accurately coincide in both the vertical and horizontal planes. Also the distance between their shafts ends does not impose any significant axial forces on the connecting coupling. If these relationships occur when the machines are operating under normal load and steady state conditions, the equipment is considered to be correctly aligned. Below we can view two diagrams which demonstrate correct and accurate alignment of a Motor and an overhung Pump. The first diagram illustrates correct vertical alignment. When we view the machinery from the side we can see if one machine is higher or lower than the other. This is the vertical alignment. In this diagram we can see the centre line of the Motor and Pump coincides exactly. The vertical alignment is correct.
The next diagram clearly illustrates correct horizontal alignment. When we view the machinery from the above we can see if one machine is to the left or right of the other machine. This is the horizontal alignment. In this diagram we can see the centre line of the Motor and Pump coincides exactly. The vertical alignment is correct.
Alignment is measured in both the horizontal and vertical planes. To achieve accurate alignment it is important to ensure that the centre lines of both machines coincide in both the vertical AND horizontal planes at the same time.
