The 2 major forms of rivets used in aircraft are the common solid shank rivets, which should be driven using an air-driven gun and bucking bar; and special (blind) rivets, which are installed with special installation tools. Solid shank rivets are used widely during assembly and repair work. They’re identified by the material that they are made, the head type, size of shank, and temper condition.
The material employed for the majority of solid shank rivets is aluminum alloy. The strength and temper conditions of aluminum alloy rivets are identified by digits and letters similar to those used to recognize sheet stock. The 1100, 2017-T, 2024-T, 2117-T, and 5056 rivets will be the six grades usually available. AN-type aircraft solid rivets could be identified by code markings on the rivet heads. A rivet made from 1100 material is designated as an “A” rivet, and has no head marking. The 2017-T alloy rivet is designated as a “D” rivet and has an increasing teat on the head. Two dashes on a head indicate a 2024-T alloy designated as a “DD” rivet. The 2117-T rivet is designated being an “AD” rivet, and has a dimple on the head.
A “B” designation is fond of a rivet of 5056 material and is marked with a raised cross on the head. Each form of rivet is identified by way of a part number to allow the user to choose the correct rivet. The numbers come in series and each series represents a particular form of head.
Countersunk head rivets are utilized in which a smooth finish is desired. The 100-degree countersunk head has been adopted as the conventional in the United States. The universal head rivet (AN470) has been adopted as the conventional for protruding-head rivets, and works extremely well as an alternative for the roundhead, flathead, and brazier head rivet. These rivets may also be purchased in two sizes by designating a “0.5” after the main length.
Replace rivets with those of the exact same size and strength whenever possible. If the rivet hole becomes enlarged, deformed, or else damaged; drill or ream the hole for another larger size rivet. Rivets might not be replaced with a type having lower strength properties, unless the lower strength is adequately compensated by an increase in proportions or even a greater amount of rivets. It’s acceptable to displace 2017 rivets of 3/16 inch diameter or less, and 2024 rivets of 5/32 inch diameter or less with 2117 rivets for general repairs, pro vided the replacement rivets are 1/32 inch greater in diameter compared to rivets they replace.
Rivet edge distance is defined as the distance from the centre of the hole to the nearest edge of the sheet. Rivet spacing is the distance from the centre of the rivet hole to the centre of the adjacent hole. Unless structural deficiencies are suspected, the spacing and edge distance should duplicate those of the initial aircraft structure. If structural deficiencies are suspected, these can be utilized in determining minimum edge distance and rivet spacing. Special fasteners may require an FAA field approval.
Blind rivets are used under certain conditions if you find usage of just one side of the structure. Typically, the locking characteristics of a blind rivet aren’t as effective as a driven rivet. Therefore, blind rivets are generally not used when driven rivets can be installed.
The 2117 rivets might be driven in the situation received, but 2017 rivets above 3/16 inch in diameter and all 2024 rivets should be kept packed in dry ice or refrigerated in the “quenched” condition until driven, or be re Rivets heat treated just just before driving, as they’d otherwise be too hard for satisfactory riveting.