Experiment 3.doc

3(a). MEASUREMENT OF ANGLE USING VERNIER BEVEL PROTRACTOR Aim: To measure the angles of given specimen using bevel protractor. Apparatus Required: Surface Plate, Dial Gauge, Slip Gauge, Bevel protractor, specimen

Applications

Procedure: 1. 2. 3. 4.

Initially bevel protractor is adjusted as per requirements. Specimen is placed between the blades. Readings noted directly from main scale and Vernier scale. Noted reading is tabulated.

Result: Thus angle of given specimens was determined.

3(b). TAPER ANGLE MEASUREMENT USING SINE BAR AND SLIP GAUGE Aim: To measure the taper angle of the given specimen using sine bar Apparatus Required: Surface plate, Dial gauge with stand, Sine bar, Slip gauge, Bevel protractor & specimen.

Specification: Sine bar

:

Range:

2

Formula: Taper angle ‘θ’ Where, h l

= Sin-1 (h/l) in degrees = the total height (thickness) of the slip gauges in mm = the standard length of the sine bar in mm = 200mm

Procedure: 1. The taper angle of the specimen is first found out approximately with the help of a bevel protractor. 2. The specimen is placed on the surface plate. 3. The sine bar bottom surface is parallel to the taper surface of the specimen. 4. The sine bar is set at this angle on the surface plate with the help of the slip gauges as shown in the figure. 5. The parallelism is checked and adjusted by increasing or decreasing the height level of the slip gauges. 6. The total height (thickness) of the slip gauges is noted down. 7. Trial readings are taken by placing the sine bar at different points of the specimen surfaces. For Small Specimen: Trial

Height of the slip gauges (mm)

Standard length of the sine bar (mm)

Taper angle (degrees)

1 2 3 For Large Specimen: Trial Height of the slip gauges (mm) h1 h2 h2- h1 1 2 3

Standard length of the sine bar (mm)

Taper angle (degrees)

Result: The taper angle of the given specimen is a. Using bevel protractor =_________________________ degrees b. Using sine bar =_________________________ degrees

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