Table of the Diameters of Rivets for Various Thicknesses
of Plates with Single Riveted Lap Joint.
| Thick- ness of Plate. | Diameter of Rivets. | ||||||||||||
| Lloyds’ Rules. | Liver- pool Rules. | English Dock- yards. | Fair- bairn. | Unwin. | Wilson. | ||||||||
| in. | in. | in. | in. | in. | in. | in. | |||||||
| 5⁄16 | 5⁄8 | 5⁄8 | 1⁄2 | 5⁄8 | 11⁄16 | 5⁄8 | |||||||
| 3⁄8 | 5⁄8 | 5⁄8 | 5⁄8 | 3⁄4 | 3⁄4 | 11⁄16 | |||||||
| 7⁄16 | 5⁄8 | 3⁄4 | 3⁄4 | 21⁄32 | 13⁄16 | 3⁄4 | |||||||
| 1⁄2 | 3⁄4 | 13⁄16 | 3⁄4 | 3⁄4 | 7⁄8 | 3⁄4 | |||||||
| 9⁄16 | 3⁄4 | 13⁄16 | 7⁄8 | 27⁄32 | 7⁄8 | 7⁄8 | |||||||
| 5⁄8 | 3⁄4 | 7⁄8 | 7⁄8 | 15⁄16 | 15⁄16 | 7⁄8 | |||||||
| 11⁄16 | 7⁄8 | 7⁄8 | 7⁄8 | 1 | 1⁄32 | 1 | 7⁄8 | ||||||
| 3⁄4 | 7⁄8 | 15⁄16 | 1 | 1 | 1⁄8 | 1 | 1⁄16 | 1 | |||||
| 13⁄16 | 7⁄8 | 1 | 1 | 1 | 7⁄32 | 1 | 3⁄32 | 1 | |||||
| 7⁄8 | 1 | 1 | 1⁄8 | 1 | 1⁄8 | ... | 1 | 1⁄8 | 1 | ||||
| 15⁄16 | 1 | 1 | 3⁄16 | 1 | 1⁄8 | ... | 1 | 3⁄16 | 1 | 1⁄8 | |||
| 1 | 1 | 1 | 1⁄4 | 1 | 1⁄8 | ... | 1 | 1⁄4 | 1 | 1⁄8 | |||
From the above it is seen that with thin plates the diameter of rivet employed is about twice the thickness of the plate, whereas as the thickness of plate increases the proportion of rivet diameter decreases, and the reasons for this are, first, that with rivets twice the thickness of thick plates and pitched so as to equalize the rivet and plate sections the pitch would be too great to permit of the seams being caulked steam tight.
The diameter of the rivet having been determined, the rivet area and area of plate left between the rivet holes may be made equal by determining the pitch by the following rule:
Rule.—To the area of the rivet divided by the plate thickness add the diameter of the rivet, and the sum so obtained is the pitch. The correctness of this rule may be shown as follows:
Suppose the rivet diameter to be 7⁄8 inch = decimal equivalent .875, and its area will be .6013 square inch. Suppose the thickness of the plate to be 9⁄16 = decimal equivalent .5625, then by the rule:
| Rivet area. | ||
| Plate thickness = .5625 ) | .6013 | ( 1.0689 |
| 5625 | ||
| 388 | 00 | |
| 337 | 50 | |
| 50 | 500 | |
| 45 | 000 | |
| 5 | 5000 | |
| 5 | 0625 | |
To this 1.0689 we are to add the rivet diameter, thus:
| 1.0689 | |
| .8750 | = rivet diameter. |
| 1.9439 | = pitch of the rivets. |
We have thus found the required pitch to be 1.9439 inches, and as the joint is single riveted there are two half rivets or one whole one to one pitch, and if we subtract the diameter of the rivet from the pitch we shall get the width of the metal or plate left between the rivets, thus: