Piping cost estimates (pt 5)
29 Mar 2000
This series on estimating the costs of pipework and piping projects might be one of the longest we have published (having started in September 1999 and continuing through October, November and January) but it reflects the importance - and complexity - of this vital part of process plant construction projects.
Previous instalments have dealt with the need to use ‘area’ and ‘job’ correction factors (September and October 1999, pp19) when estimating piping costs; cost estimates for cutting various grades of piping in established site workshops (November 1999, p19); and similar estimates for the welding of pipework, again in workshop conditions (January 2000, p18).
This month we take the job outside and present graphs to estimate direct field labour costs.
The scope of the data is to provide direct field labour in manhours per linear metre for erection of overhead pipework 3m above grade level. These minimum manhours include for loading at the material storage site, transport to the working area, and unloading.
Also included is the cutting, threading, rigging, temporary supports, alignment, temporary bolting, tack welding as necessary of prefabricated pipe spools or random lengths of pipe.
Not included are beam clamps, hangers, fittings, bolt-ups, supports, valves, special welding or testing.
It should also be noted that pipework erected at or near grade level should be subjected to a 50 per cent reduction from the manhours derived from the graphed data. PE
