We need to add from the bolt table standard the first bolt length for the respective bolt diameter. For example a 1316 in.
Timber Bolts Portland Bolt
Standard bolt length increments. Mm standard thread length mm. 14 34 1 516 78 1 18 38 1 1 14 716 1 18 1 38 12 1 14 1 12 58 1 12 1 34 34 1 34 2 78 2 2 14 1 2 14 2 12 important note. Depending on the diameter there may be longer lengths available. Delta of the bolt length. Some bolts may vary from the standard thread length. Generally speaking bolts over 1 12 in diameter should be designed in 14 increments regardless of grade.
While it is possible to manufacture bolts in 18 increments ie. Plain finish or hot dip galvanized. Steel availability steel round bar used to manufacture bolts is not readily available in 18 increments over 1 12 diameter. Bolt diameters between 58 and 1 12 come in 18 increments the lengths of small bolts 12 come in 18 increments the lengths of large bolts 12 come in 14 increments. Note that the rcsc specification in the footnote of table 31 allows a 132 in. 2 38 there are several reasons why you would want to avoid it.
Bolts 125mm and shorter. Trying to make sense of all the different screw and bolt thread lengths can be a real challengeeven for the most knowledgeable of professionals. Tolerance on these maximum hole sizes as discussed in 242 and 255. Slotted hole for a ¾ in diameter bolt must be treated as a long slotted hole because it exceeds the maximum short slotted hole size 1316 in. Bolts longer than 125mm. Portland bolt manufactures a325 and a490 heavy hex structural bolts from 12 diameter through 1 12 diameter typically in lengths longer than those which are normally available in the marketplace.
This is defined for each rule and it is the length increment for the bolt. A line is automatically created in the bolt list by taking the first bolt length set on the previous tab and then adds this. Some bolts may vary from the standard thread length. Up to 6 10 maximum depending on diameter available finish. Bolt diameter standard thread length in bolts 6 inches and shorter bolts longer than 6 inches.
Gallery of Standard Bolt Length Increments
