Structural Steel Fabrication Tolerances

Tolerances are grouped three distinct categories.

Structural steel fabrication tolerances.

The tolerances for steel construction can be divided into three general areas. Astm a6 is incorpo. Specifications covering fabrication of structural steel do not in general require closer tolerances than those in a6 but rather extend the definition of tolerances to fabricated members. An engineer designing with structural steel must account for three types of toler ance in their design.

Tolerances for the fabrication of structural steel both hot rolled and built up members can be found in standard codes such as the aisc specification for structural steel buildings. These are the limits of permissible deviation for the mechanical resistance and stability of the structure and are used to support conformity assessment to bs en 1090 1. This code provides a useful framework for a common understanding of the acceptable standards when contracting for structural steel. For the most part the tolerances for welded members are the same as those for rolled members produced under astm a 6 even though rolling mill practice has only limited direct bearing on welded built up members.

Mills producing hot rolled structural steel must conform to the astm a6 speci fi cation as stated in aisc s manual of steel construction 13th edition. One particular tolerance require ment to insure structural integrity involves the tilt or out of square limits for flanges. 6 2 marking for erection. 6 1 accuracy of construction.

5 3 cross section of members fabricated from plates or built up from sections 5 4 length. Fabrication 8 1 cutting drilling deformation and punching of members. As such it is useful for owners architects engineers general contractors construction managers fabricators steel detailers erectors and others associated with con struction in structural steel. The faqs in this section include a discussion of portions of these provisions and subsequent recommendations.

6 4 erection of structural steelwork. 6 3 delivery storage and handling. There are also tolerances on surface quality of structural steel. Mill tolerance fabri cation tolerance and erection tolerance.

6 6 protective treatment. The aisc specification for structural steel buildings the code of standard practice for steel buildings and bridges aws d1 1 and other existing specifications and codes cover tolerance requirements for the fabrication and erection of structural steel. 5 5 straightness in both axes. 5 2 cross section of rolled sections.

Design purchase fabrication and erection of structural steel.