It is commonly assumed that fabricator's objective is to sell steel, when in reality his role is the conversion of rolled steel into finished goods by added value. This is achieved by selling workmanship and machine utilisation on a competitive basis where costs are directly related to time.
Relying increasingly upon production engineering techniques, success in this direction depends upon better standardisation. Time and therefore labour costs can be cut significantly by the repetition of dimensions and member sizes and shapes, centres and diameters of bolts etc., all of which are amenable to rationalisation. Further economy is derived by reducing the number of detailed components which tend to be labour intensive even when this results in heavier parent members.
By tradition, fabricated steelwork is often quoted on the basis of $/tonne and whilst this is an accepted arithmetic convenience, it can be completely mis-leading since true cost identity is obscured. In practice, the fabricator estimates costs by seperating the various activities into categories such as cutting, drilling and welding which enables man hours to be allocated and valued to arrive at a total price.
Relying upon a combination of historical data and practical experience, the cost build-up bears little relationship to the weight of steel involved although cost references in $/tonne can be a useful index for a rapid comparison of different classes of work.
Fig. 1 shows an average breakdown of costs for building structures in the light to medium category which is intended to be representative rather than absolute because of differences in accounting practice.
