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alignment tests on pillar type drilling machine
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Machine Tool Metrology
Alignment tests on pillar type drilling machine – A case study
By
Mr.B.Ramesh, M.E., (Ph.D.),
Associate Professor,Department of Mechanical Engineering,,
St. Joseph’s College of Engineering,Jeppiaar Trust, Chennai-119
April 11, 2023 2
INTRODUCTION
• Machine tool metrology• The alignment test on a machine tool is carried out to check the grade of
manufacturing accuracy of the machine tool.
• The geometrical checks made on machine tools are :
* Straightness and flatness of guide ways and slide ways of machine tool.
* Flatness of machine tables * Parallelism, equidistance and alignment of the slide ways. * True running and alignment of shaft and spindle. * Lead of lead screw or error in pitch.
• The geometrical test is carried out to check the grade of manufacturing accuracy of the machine tool.
• Practical test is carried out to check the accuracy of the finished component.
• Geometrical test consists of checking the relationship between various machine elements when the machine tool is idle.
• Practical test consists of preparing the actual test jobs on the machine and checking the accuracy of the jobs produced.
April 11, 2023 3
• Static tests• Dynamic tests• Importance of alignment test : The geometry of various shapes is based on
the relative motion between various machine parts and hence on alignment of various parts.
• Other parameters subjected to tests are : * Stiffness and rigidity of the machine tool and its components parts. * The quality and accuracy of the control devices and the driving
mechanism.
April 11, 2023 4
Alignment tests on pillar type drilling machine * Properly Installed – In both horizontal (longitudinal and transverse directions) and vertical directions.
1. Flatness of clamping surface
of base: * Straight edge on two gauge blocks
* Feeler gauges gives error
* Error should not exceed 0.1/1000 mm
clamping surface
* Surface should be concave only
2. Flatness of clamping surface
of table:
April 11, 2023 5
3. Perpendicularity of drill head guide to the base plate :
* Tested in both vertical plane(a) and in a plane at 900 to the above plane (b)
* Frame level with graduations from 0.03 to 0.05 mm/m
* Error should not exceed 0.25/1000 mm for (a) and 0.15/1000 mm for (b)
4. Perpendicularity of drill head guide with table :
5. Perpendicularity of spindle sleeve with base plate :
* Tested in both the planes using frame level
* Error should not exceed 0.25/1000 mm for plane (a) and 0.15/1000 mm for plane (b)
April 11, 2023 6
6. True running of spindle taper :
* Test mandrel is palced in the tapered hole of spindle
* Dial indicator
* Spindle rotated slowly
* Error should not exceed 0.03/100 mm for machines with taper upto Morse No. 2 and 0.04/300 mm for machines with taper larger than Morse No. 2
April 11, 2023 7
7. Parallelism of the spindle axis with its vertical movement :
* Test is performed into twp planes A & B
* Test mandrel and dial indicator
* Spindle is adjusted in the middle position of its travel
* Permissible errors are : For machines with taper upto Morse No. 2 0.03/100 mm for plane A and 0.03/100 mm for plane B.
* For machines with taper larger than Morse No. 2 0.05/300 mm for plane A and 0.05/300 mm for plane B.
April 11, 2023 8
8. Squareness of clamping surface of table to its axis :
* Dial indicator
* Table is slowly rotated
* Error should not exceed 0.05/300 mm diameter
April 11, 2023 9
9. Squareness of spindle axis with table :
* Straight edge placed in position AA’ and BB’
* Work table in middle position of its vertical travel
* Dial indicator
* A – 1800 – A’
* The permissible errors are 0.08/300 mm for AA’ and 0.05/300 mm for BB’.
April 11, 2023 10
10. Total deflection :
* Drill head and table are arranged in their middle position.
* Dial indicator* Dynamometer
April 11, 2023 11
Thank You