Generally there are only two methods for the erection of structural steel connections to structural steel members; shop operations and field operations. Field operations are required to make the final adjustments between the members, but are usually most costly due to the labor and processes involved. Shop operations reduce labor cost, and are usually maximized as much as possible, such as welding connection elements to the structural members. In most cases, the erection of structural steel connections is a combination of both shop and field operations. The method of steel connection erection is a common classification for steel connections, as discussed here.
Shop operations
Shop operations are most common and desirable for welding since the cost of field welding is much higher and can pose complications. For bolting or riveting, shop operations can involve pre-drilling of the structural steel members, however the assembly of the bolts / rivets is typically done in the field.
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Field operations
Field operations typically include the assembly of rivets or bolts between the connecting members. Field welding is also done for some types of connections, however it is generally avoided due to the high cost associated with labour. For connections that are all welded, field welding is necessary, however some cost can be reduced by shop welding the connecting element to either the supporting (parent) or supported (child) member beforehand, and only field welding the other side.
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