Equipment costs, estimation insulation

Equipment Costs. Equipment costs include the purchased cost of process and materials handling equipment, storage faciUties, waste treatment equipment, stmctures, and site service faciUties. Installation costs such as insulation, piping, painting and finishing, foundations, process stmctures, instmmentation, and electrical service connections are estimated or factored separately. Actual quoted prices from suppHers are the best data, but these are not usually available when estimates are made. The quick, inexpensive cost estimates are based largely on personal cost files, internal company cost data, or pubUshed cost correlations. 

For instance, equipment made of monel generally costs 6.5 times as much as the same item constructed of carbon steel. If 25% of the equipment purchased for a plant were made of monel, this would increase the equipment costs by 237%, and the factor cost estimate would be 2.37 times that for a plant constructed of carbon steel. This is unreasonable, since the cost of buildings, roads, wiring, piping utilities, insulating, and instrumentation are independent of the materials of construction. In fact the only major changes would be in the process piping, which,... 

When very high or very low temperatures are involved, insulation factors can become important, and it may be necessary to estimate insulation costs with a great deal of care. Expenses for equipment insulation and piping insulation are often included under the respective headings of equipment-installation costs and piping costs. 

The Insulation account in Appendix L was factored to the equipment cost. However, as mentioned in Chapter 10, factored estimates are not suitable for construction progress tracking. 

BM factor method of cost estimation. Component costs within the BM are estimated as percentages (or factors) of the FOB cost. The factors differ depending on the type of equipment in the module and the alloys. Two types of factors have been developed (1) L + M factors to account for the FOB cost plus the materials and labor for the supports, concrete, electrical, process and utility piping, vents and sewers, insulation, and painting, plus labor for inspection and installation but excluding instruments and instrumentation. (2) Indirect cost factors for home office and field expense. 

Boiler cost estimates include fittings, refractory, insulation and cladding for outdoor installation, internal piping, platforms and stairs, burner and flame safety equipment, economizer, force-draft fan plus drive and soot blowers. 

Computing Installation Costs. When delivered equipment costs are the only data available, installation costs must be estimated. These costs,include labor, foundations, supports, platforms, site preparation, normal temperature-level insulation, and other factors directly related to the erection of equipment. Table 6-3 (p. 214) gives installation costs as a percentage range of delivered equipment costs for various types of equipment. As a general rule, costs for equipment installation are often estimated as 43 per cent of the delivered equipment costs. ... 

A popular overall factor refinement, known as the Hand factor approach, uses a different factor to estimate overall costs for each class of equipment to cover all labor field materials, eg, piping, insulation, electrical, foundations, stmctures, and finishes and indirect costs, but not contingencies. Hand factors range from 4 for fractionating towers down to 2.5 for miscellaneous equipment. 

Major items of equipment include reactors, heat exchangers, columns, vessels, etc. Ancillary equipment such as process piping and insulation can be estimated after the total cost of the major items is known. 

If a 100,000 heat exchanger is to be added to an existing crude unit, the cost of installing it will normally be far less than the 230,000 calculated from Table 8.2. This is because the sewers, control room, and instrument loops are already in place. The foundation, piping, and insulation of the exchanger might cost 80,000 to 160,000. It is simply not possible to estimate an installed cost of one or two items of process equipment without considering each case on an individual basis. 

The sum of costs for piping, insulation, and instrumentation can be estimated to be 60 percent of the cost for the installed equipment. Annual fixed charges amount to 15 percent of the total cost for installed equipment, piping, instrumentation, and insulation. 

Insulation - The take-offs for piping insulation are developed as part of the piping account estimate. The take-offs for equipment insulation are developed by identifying and estimating the outside area of those items requiring insulation. The unit prices in Section 19.5 are used to estimate cost. 

When construction is to be subcontracted, some accounts (civil, insulation, and paint) are usually estimated on a total cost basis, combining both materials and labor. Other accounts (piping, electrical, instrumentation, equipment erection) are estimated and shown separately as material and labor. In that case, the labor should be loaded with the subcontractor s field indirects plus overhead and profit. The field indirects would reflect only the cost of construction management. 

To roughly estimate the total direct cost of the drying installation, it is recommended to multiply the equipment FOB cost by a factor of 2.25 if the equipment is made of carbon steel or by 2.75 if stainless-steel equipment is used [29]. These figures include the cost of piping, instrumentation, electrical connections, insulation, building space, and engineering when applied to spray, flash, rotary, or fluid-bed continuous dryers. In specific cases, however, different factors may have to be used. For instance, the costs of instrumentation and piping may be included in the purchase price of a fully equipped dryer [30]. 

As discussed for the depropanizer, Aspen IPE prepares the Capital Estimate Report, MCB.ccp, which contains detailed listings of the items to be procured to install the equipment (classified in the areas of piping, instrumentation, electrical, structural steel, and insulation), estimates of the man-hours required for installation, estimates of the costs, and an installation schedule. Estimates for contractor engineering and indirect costs are listed as well. 

It will be evident that the accuracy of factorization techniques depends on the similarity of the type of plant, and also the consistent grouping of cost elements into the factorized components. A plant which is intensive in bulk solids handling is not comparable to an oil refinery. If the cost database is inconsistent as to whether, say, thermal insulation costs are included under piping on one project and under mechanical equipment on another, accuracy will be reduced. When there is a reasonably consistent database of reasonably similar plant, factorization of the mechanical equipment total may yield an estimate for which an accuracy of 25 per cent can be claimed. This could be narrowed to say 20 per cent if the more advanced factorization techniques are used, but hardly better unless there is extreme confidence in a recent database of very similar plant. 

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