1. Example 1. threaded pipe joints, require precision in manufacture as monitored by screw gauges. That denotes 46 divisions - each division is 0.01mm so we have 0.46mm from this scale. Add the vernier scale reading to the main scale to get the answer. And The space between all these is equal to one. To more about the different parts and the working principle of the micrometer screw gauge read here.Having a U shaped metallic frame, a micrometer screw gauge measures even the minutest length with acute precision. Multiply this “n” with the least count and calculate the value of fraction (x) which is to be added in the main scale reading. A measuring equipment can give precise but not accurate measurements, accurate but not precise measurements or neither precise nor accurate measurements. Comments(0) Log in to comment. Place the wire between the anvil and the screw and note down the PSR and HSR as before. Accuracyis a measure of how close the results of an experiment agree with the true value. of Full rotation taken) If with the wire between plane faces A and B, the edge of the cap lies ahead of Nth division of linear scale. The circular scale of a screw gauge has 50 divisions and pitch of 0.5 mm. A screw gauge of 100 divisions will move the cap scale along the main scale by 1/100 of mm-0.01 mm. Worksheet ( Vernier Calipers / Micrometer Screw Gauge ) ANSWERS. Find the radius of the spot r, which is corresponding to Imax/2.71 (See the figure 5). 0.28. Reading micrometer screw gauge. A screw gauge consists of ratchet, thimble, sleeve, spindle and anvil. SREE CHAITANYA COLLEGE OF ENGINEERING DEPARTMENT OF MECHANICAL METROLOGY LAB MANUAL VERNIER HEIGHT GAUGE: Vernier height gauge also works on the same principle on which vernier caliper works. 1. In order to measure an object, the object is placed between the jaws and the thimble is rotated using the ratchet until the object is secured. NPL NOTES ON SCREW GAUGES “Interchangeability and quality of fit of nuts, bolts, and other screwed fasteners e.g. Measure the detector reading from output unit and tabulate it. 5/16 head times two equals 10, minus two equals 8. The formula for pitch is given by: Pitch of the Screw = (Distance travelled by the screw) / (No. Usually the least count of a scale is 1 We can measure the length of objects up to mm accuracy using this scale. Screw gauge is an instrument used to measure small lengths, such as the thickness of a thin glass plate or the diameter of a wire or that of a small lead shot. If D be the mean diameter and l be the mean length of the wire,Volume of the wire, Diagram Procedure. 1.01 cm. They are calibrated in cm and mm scales. On the diagram this reading is 2.5 mm Now look at the rotating scale. = n x (L.C.) (L.C. X = ( n × LC ) Add the values ‘M ‘ and ‘X ‘ … Thimble reading = 22 x 0.01mm = 0.22 mm. 1.14 cm. ü The divisions in the thimble scale multiply by 0.01mm. This is the minimum value up to which a screw gauge can measure and is known as its least count. 2. notesforfree.com/.../measure-diameter-volume-given-wire-using-screw-gauge The accuracy of a reading can be improved by repeating the measurements. = N If nth division of circular scale lies over reference line. Vernier micrometer reading worksheet. + corrected H.S.R. The diameter of wire from the above data is : + C.S.R. b. Case (a): No zero-error Case (b): Positive zero-error of 2 circular scale division. The circular which is made in the micrometer He passes near. the main scale reading is (1-49/50)=0.02mm. The body used to hold the anvil and barrel firmly in their place is called a frame, in micrometer screw gauges, thick C shaped frames are used. Find the diameter of sphere. It comprises of a U-shaped mount which is fixed with a screwed pin which is fixed to a thimble. APPARATUS Screw gauge, wire. Plot the graph between X in x-axis and output reading in y-axis. The pitch of the screw gauge can be defined as the distance travelled by the spindle per rotation. When there is high accuracy (accurate shots), there will be small systematic error 2. = N+n x (L.C.). It is based upon the principle of a screw. Vary the detector distance X by an order of 0.5mm, using the screw gauge (use up and down arrow on the screw gauge to rotate it). Then, circular scale reading (C.S.R.) So the answer is 208 cm. Sleeve reading =7.5mm. Main scale reading is 2 -