1.0 Title : M6 Roughness Measurement 2.0 Objective of Experiment : i. To understand the operation and application of the equipment ii.

To determine the roundness of the work piece 3.0 Introduction and Theory : The FORM-PC The FORM-PC is a measuring, control and evacuation software program for Formtesters. The FORM-PC controls the Formtester, records the measuring values, process the measuring values, determines the form and position deviations, documents and logs the measuring result. The FORM-PC with its three modes of operation, namely Quick&Easy for quick results and unexperienced users, Teach-in Programming for running highly complex measuring programs without any programming knowledge and Measuring run for running measuring programs provides solutions for any problem. Measuring Station The standard measuring station comprises the : i. Formtester All formtester are measuring machines for determining deviations of form and position on axis-symmetrical testpieces. They essentially consist of a centering and tilting table, the measuring and positoning axes, the keypad with joystick, and the EMERGENCY switch. ii. FORM-PC interface The FORM-PC interface enavles communication between the Formtester and the FORM-PC. It edits the data transmitted from the Formtester to the FORM-PC and vice versa. The interface is only required for specific measuring station combinations. 4.0 Experiment Equipment : Formtester MMQ -10, FORM-PC and workpiece

Figure 6.1 : Formtester MMQ -10, FORM-PC and workpiece 5.0 Procedures : 5.1 Preparation 5.1.1 Probe The Probe arm is first positioned vertically and then slightly inclined towards the workpiece. The angle should be in the range of 10 .

Figure 6.2 : Probe IMPORTANT : Probes are highprecision element which must be handled with care. Probe failures are mainly caused by improper handling. Do not allow grease, oil or any fluid to get inside the probes. 5.1.2 Tracing force and tracing direction The tracing force is adjusted on the T2W with the knurled knob (22) such that the mark points to the first scale division above or below the zero point of the scale :

For the measuring tasks depicted in this booklet please use : For external measurements : first scale division (21) above the zero point For internal measurement : first scale division (23) below the zero point 5.1.3 Turntable The turntable features centering and tilting facilities. Centering with the rotary knobs X and Y Tilting with the rotary knobs A and B The measuring station indicates both the rotary knob to be used and how much it must be turned. In case the table is to be rotated manually, Do never use the rotary knobs as points of attack, Do only rotate it clockwise

Figure 6.3 turntable and T2W 5.1.4 Setting up the Workpiece Before measurement may commence, the test element (the form element to be tested on the workpiece) must be aligned. For this purpose, the eccentricity is assessed. Afterwards, the centering rountine is started in which the test element is centered with respect to the C-axis in the given measuring plane. During the centering process, the operator prompting outputs information on how to turn the rotary knobs X and Y for the centering axes to reduce the assesses eccentricity. Long form elements have to be aligned with the centering & tilting rountie, i.e. they have to be centered first with respect to the C-axis before their axes of rotation are aligned parallel to the C-axis. This requires measurements in two planes of different height after which the eccentricity is

calculated. Afterwards the form element is centered with the rotary knobs X and Y and then titled with the rotary knobs A and B. Since the centering and tilting rountines mutually influence one another, new measurements are necessary thereafter to correct the workpiece position once again. The model workpiece is to be centered with respect to the C-axis such that a residual eccentricity of only 0.5 m remains. 5.1.4.1 Workpiece setting-up through Centering

Figure 6.4 : workpiece set up i. Clamp the workpiece roughly precentered (visual estimate). ii. Use the rotary knob (11) to move the probe to the height of the centering plane, i.e. to 165mm. (Read off the value at mark (9).) iii. Enter the workpice diameter, i.e. the diameter of the form element in the measuring plane (50mm). iv. Set the probe signal to zero v. Select the centering rountie : vi. Enter the height of the measuring plane (165mm) : a) Take the measurement : o Press

The measurement is carried out, the result indicated. o Press. The assessed eccentricity is indicated. o Check whether the assessed eccentricity value is smaller than the given value of 0.5 m. o If Yes : Complete the centering rountie and if No : Continue with b). b) Centering rountie: o Move the turntable (2) to the angular position 315 . o Turn the rotary knob X such that the arrow approximately points to 0. o Turn the rotary knob Y such that the arrow approximately points to 0. Continue with a) Repeat the steps a) and b) until the assessed eccentricity value is smaller than 0.5 m.

Figure 6.5 : turntable 5.1.4.2 Workpiece Setting-up through Centering and Tilting i. The model workpiece is to be aligned with respect to the C-axis such that the eccentricity over two measuring planes is smaller than 5 m. ii. Clamp the workpiece roughly precentered (visual estimate). iii. Use the rotary knob (11) to move the probe to the height of the first measuring plane, i.e. 135mm. iv. Enter the workpiece diameter, i.e. the diameter of the form element in the measuring plane (50mm). v. Set the probe signal to zero vi. Select the centering and tilting rountie :

a) Enter the height of the first measuring plane (135mm) : o Take the measurement (in the 1st measuring plane) o Use the rotary knob (11) to move the probe to the height of the second measuring plane, i.e. 190mm. o Take the measurement (in the 2nd measuring plane) o Check whether the assessed eccentricity value is smaller than the given value of 5m. o If Yes : Complete the centering & tilting rountie with and if No: Continue with b). a) Centering rountie : o Move the turntable (2) to the angular position 315 . o Turn the rotary knob X such that the arrow approximately points to 0. o Turn the rotary knob Y such that the arrow approximately points to 0. a) Tilting rountie : o Move the turntable (2) to the angular position 135 . (Rotate clockwise, do not use the rotary knobs as points of attack) o Turn the rotary knob A such that the arrow approximately points to 0. o Turn the rotary knob B such that the arrow approximately points to 0. o Use the rotary knob (11) to move the probe the height of the first measuring plane, i.e. 135mm. Repeat the entire process starting with a) Enter the height of the first measuring plane (135mm) until the eccentricity over the first and second measuring plane is smaller than 5m. 5.2 Measurement a) Roundness

The roundness error is to be determined in the middle of the lower cylinder of your model workpiece. The assessed roundness error should lie within a tolerance of 10m.

Figure 6.6 : Roundness of workpiece i. Set-up the form element to be tested (i.e. the lower cylinder) ii. Use the rotary knob (11) to move the probe to the height of the measuring plane, i.e. 160mm. (The middle of the lower cylinder is about 30mm above the base of the model workpiece. The zero point of the workpiece coordinate system is at about 130mm of the machine coordinate system. Since the measuring station operates in the machine coordinate system, a height of 160mm has to be approached.) iii. Enter the workpiece diameter, i.e. the diameter of the form element in the measuring plane (50mm) (In order to determine profile edge zones correctly, the workpiece diameter must be entered as precisely as possible.) iv. Select the roundness feature : v. Enter the height of the measuring plane (160mm) vi. Enter the tolerance value (10m) according to the drawing specification (top left figure) vii. Take the measurement. b) Roughness on an Interrupted Form Element On the upper cylinder, the roundness error is to be determined at the height of the groove (i.e on an interrupted form element). The assessed roundness error should lie within a tolerance of 10m.

Figure 6.7 : Roundness on an interrupted form element i. ii. iii. iv. v. vi. vii. Align the form element to be tested (i.e. the upper cylinder). Enter the workpiece diameter, i.e. the diameter of the form element in the measuring plane (30mm) Use the rotary knob (11) to move the the probe to the height of the measuring plane, i.e. 235mm. Select the roundness feature : Enter the height of the measuring plane (235mm) : Enter the tolerance value (10m) according to the drawing specification (top left figure) Enter the width of the profile edge zone ( 10 ) : (Within the specified prf.edge zone, the profile is not evaluated. As a rule, these zones are situated at the edges of profile interruptions.) Enter the undulation cutoff for the filter: (With an undulation cutoff of 15 upr, the roughness and waviness components of the profile are suppresses such that basically only the form components remain.) Take the measurement.

viii.

ix.

6.0 Discussion : i. ii. The roundness of the work piece is determined by using Formtester MMQ -10, and FORM-PC and the result is printed. The Definition of roughness is : a. Is measure to make sure that the round object is round from inside and outside b. Is the characteristic that all parts of a circle are identical The precaution steps or ways to improve the result of the experiment : a. Rotate clockwise -the turntable only can be rotated in the direction of clockwise b. Never use rotary knobs as points of attack when rotate the turntable c. Make sure the surface of the workpiece and all the equipment is cleaned before the experiment started. d. Minimize vibration, temperature change and air flow e. The experiment is repeated several times in order to improve the result of the experiment Advantages of Roundness measurement : a. Data collection -Capable of continuous form measurement -Thousand of data points around the circumference of part giving the ability to map the parts form accurately b. Roundness testing system often referred to as form measurements system because of the several part features theyre capable of measuring. Along with roundness, todays roundness testing are equipped to measure flatness, squareness, and etc as showed in the table below :

iii.

iv.

Figure 6.8 : Several uses of Roundness testing system

v.

Applications of roundness measurement on fields : a. Medical -Form or shape of artificial ball joints. b. Manufacturing -Bearing, automotive, aerospace, etc. -for checking the roughness of components -for checking the straightness of shafts used in precision application such as cam shaft, centrifuge, hydraulics etc. c. Machine tool Mfg. -Any major tool maker supplying precision manufacturing equipment. d. Military -used by the Air Force and other branches of the military to check the quality of incoming or reconditioned aircraft and defense parts.

7.0 Conclusion : As a conclusion, the roundness of the work piece is determined by using Formtester MMQ -10, and FORM-PC and the result is printed. From this experiment, we have learnt about the Roughness Measurement process including industrial applications, and its advantages through laboratory work and its precaution step. Besides that, we have understood the operation and application of the equipment used in this experiment. 8.0 References : i. ii. iii. Lab sheet Manufacturing Engineering and Technology, Serope Kalpakjian, Steven R. Schmid, 5th edition in SI units, Prentice Hall. Internet : a. http://www.qualitydigest.com/dec02/articles/01_article.shtml b. http://www.emigage.com/lab.htm