The components which make up the complete metal member or structure are fastened together by means of rivets, bolts, or welds. Rivets are made from rivet bar stock in a machine which forms one head and shears the rivet to the desired length. Rivet heads are usually of a rounded shape called a buttonhead. The head may be flattened when clearance is limited. When very little clearance is available, countersunk heads are used. Countersunk heads are chipped flush if no clearance is available. Information concerning conventional signs for riveting, sizes of heads, weights, lengths, and other data are given in the AISC steel construction manuals.
Steel rivets are almost always heated before driving. In the shop the rivet is heated to a minimum temperature identified by a light cherry-red color. Most shop rivets are driven by pressure-type riveters which complete the riveting operation in one stoke.
Riveting guns are portable hand tools, operated by compressed air, which drive the rivet by a rapid succession of blows.Rivets are made from steel conforming to the specifications for rivet steel, ASTM A502. this specification covers two grades of steel. Grade 1 is a carbon steel for general purposes.
Grade 2 is a carbon-manganese steel
for riveting high- strength alloy structural steels. Rivet heads are marked to
identify the manufacturer and with a numeral 1 or 2 to identify the grade; the
manufacturer may omit the numeral 1.
6053-T61 Aluminum |
Rivets used in fabricating structures of aluminum alloys may
be driven either hot or cold. Cold-driven rivets for structures of alloy
6061-T6 and 6062-T6 are made from alloy 6061-T6 and for structures of 6063-T5
and 6063T6 from alloy 6053-T61. cold-driven rivets for structures of alloy
2014-T6 are made from alloy 2117-T3. hot-driven rivets for the five alloys are
made from alloy 6061-T43.
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