392

RIVETING AND THE SHEARING OF

Experiments on the Double Shearing of Bars of Rivet-iron,as above, Diameter %-inch.

Weight in Tonsper sq. inch

Experiment. of section.

5. Area of the two sections 1-2026 . 22-9

6. Ditto. 2 1 *6

7. Ditto. 21-6

8. Diameter f|^-inch. 22-5

9. Ditto . 22 5

10. Ditto . 22-5

11. Ditto, bar -J-inch diameter . 21-6

12. Ditto ditto . 21-6

Mean . 22-1

The mean result from these experiments gives 23 - 3 tonsper square inch as the weight requisite to shear a single rodof rivet-iron of good quality. The ultimate tensile strengthof these same bars was also found to be 24 tons; hence theirresistance to single shearing was nearly the same as theirultimate resistance to a tensile strain.

To avoid any anomalies from the use of the lever, or fromthe fitting of the pin loosely in the hole, two plates f-inchthick were now riveted together by a single rivet f-inchdiameter, and the rivet was sheared by suspending actualweights from the plate ; the rivet thus sustained 12-267 tons,or 20 - 4 tons per square inch.

Three plates were then united by a similar rivet, and therivet was sheared in two places by the centre plate. Theultimate weight suspended from the rivet was 2fJ*8 tons, or32'3 tons per square inch of section.

Value of Friction produced by the Cooling of Red-hot

Rivets.

In all the above experiments the object in view wasto ascertain the resistance of a pin or rivet to a shearing