ANALYSIS OF ALIGNMENT READING BY THROW CIRCLE METHODS

ANALYSIS OF ALIGNMENT READING BY THROW CIRCLE METHODS
1. To analysis alignment reading one will need the following items.
1.1. One good graph paper to plot the displacement recorded in the X & Y direction.
1.2. One Good geometry box with pencil, eraser, pencil sharpener, scale, compass, divider, protractor and set squares etc.
2. Now in the graph paper plot co-ordinate axis amd mark XX' and YY' axis.
3. To find out the throw plot the dispalcement of (x, y) on a graph paper to a suitable scale. For example plots points (0,0) ; (1,-3.5); (0,-1) ; (0.5 , -1) ; (1.5 ,0) ; (1.5,-6.5) ; (-1.5 ,-3) ; (-6.5,-2) & (-3.5,0) LGB reading of combined alignmnet checking.
4. Out of the total eight co-ordinate points three co-ordinate points have to choose in such a way that when a circle is drawn with minimum radius will pass through these three points and also includes all other points within the circle.
4.1. To draw the circle first draw a triangle with the selected three points. Then draw bisector of all the side. The cross section of all bisector will be the centre of the circle. Now taking the cross-section points as the centre and any other points as radius circle can be drawn.Diameter of such a circle should be in close agreement with the throw (run out ) reading obtain in factory. The throw will be half of the throw circle diameter. The throw circle should not exceed 0.1 mm. The angle of throw can obtained by drawing a line connecting centre of co-ordinate axis and and centre of the circle.
5. The throw at lower guide bearing and the turbine guide bearing journal to be calculated independently and necessary correction measure to be taken independently.