TITIS: Vernier and Micrometer

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Apply foree wire mediod to determine the pitch diameter of a threat

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Figure I: Vernier caliper

Micrometers are normally used for measurement of emaller dimensions with greater precision than calipers. Mierumeters are used for mensoring dimensions dependizt an types of anvila and frames Dastance mesurument is achicve referencing the lineat displacement of spindle to a fixed measurime face on axis of spindle $($anvil$).$ They commonly hive one of two types of reat$-$out devices a micrometer scale, or electronic I CD divplay. The accuracy of micrumet ers is approximately i $10$ um Merromets have a ratchet tightening screw to ; provide a standud pressare betwoen the tool and the part. The main components of micrometer are shown in Figure $2$

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Figure $2$: Micrombier pitch $($center$)$ diameter. The most universal mochod of obtaining meaturement of gitsh diameter, taper, an out$-$of$-$roundess of extornal threads is the these$-$wire method, In checking serew threads by the these$-$wire method, thees wire of the aame diameler for the partacular patch being checked are placed in contact with the threaded part. Twe wires we placed with the thread on one sule, and a thard wire on the opposic side. Thee wire measuremeat with merumeter is in Figure $3$

Figure $3.$ Ilare wire beasurnent bith microacter

APPARATUS:

Vermier calipor

Misromater caliper

$3$ steal gaze wire

Heragou lead norews