Estimating engineering hours

The estimating system presented here proposes a relatively simple but accurate method for estimating engineering hours based on the equipment list and a general knowledge of the project particulars. It was developed from published data and a thorough analysis of nine actual projects. The analysis of the data resulted in several adjustment and correction factors - some empirical, some theoretical that recognize, and try to compensate for, the effect of conditions specific to each project, such as ... 

Engineering hours are intimately related to equipment count and type. When a complete equipment list is available, the procedure included in Chapter 19 can be used to prepare accurate estimates. However, this is seldom the case in the early stage of any project and the project managers must do the best they can with the information they have. 

Compliance to and documentation of regulations increase the engineering hours required to execute the project and the Project Manager must ascertain that they are acknowledged and the impact on cost, and sometimes schedule, is included in the cost estimate and project execution plan. 

As part of the technical analysis, the Project Manager must analyze bidder takeoffs to ascertain the bidder s understanding of the scope and will also analyze unit costs and estimated hours for reasonableness and consistency. To do so, the Project Manager must develop, using the same information sent to the bidders, independent take-offs and estimated work hours. Major deviations from the estimates must be discussed with the Contract Engineer to determine how to approach the bidder on the subject. 

Estimate the hours required to perform the detailed engineering in-house as well as by contractors. 

Engineering - Contractor s engineering hours must be estimated with the procedure in Section 19.8. The cost per hour including overheads... 

Note The proposed execution approach will influence the required engineering hours and must be taken into account when preparing the estimate, especially a definitive or appropriation type estimate. Refer to the discussion in Section 15.3. 

Estimating engineering costs as a percentage of the direct project costs is a very common practice in conceptual and preliminary work. It is very simple but also very risky. The engineering hours related to any piece of equipment have very little relation to its cost. 

Table 19.25 Engineering Hours Estimating System Performance...

The use of object-oriented software has been estimated to save literally millions of dollars on new plants, and these savings only estimate the savings in actual engineering hours. These savings will obviously be reflected in the reduced cost associated with vaiidating standard objects as opposed to application-specific or bespoke software. 

Investment Fixed Cost per a Plastics Production Plant to escalate to world class. It is possible to define an ideal as the necessary estimated investment to escalate to world class. To achieve this end, the necessary acquisition expenses were investigated for the commercial equipment recommended on the technological studio performed in Phase 3 for the gap elimination. The costs indicated in this format don t include engineering hours, consulting, installation or transportation. 

A small engineering building is located 350 ft (107 m) from the process unit discussed in Example 8. It has an occupancy load of 500 person-hours, which exceeds the company s occupancy criteria. The building is constructed of unreinforced concrete and contains several windows. Earlier calculations estimated the incident side-on overpressure to be 0.5 psi at 350 ft (0.069 bar at 105 m). 

Before an economic balance can be completed, the number of men required to operate the plant must be estimated. A list of some of the types of employees is given in Table 8-10. Note that these categories include only those people involved directly in production and maintenance, and not purely administrative, research, and sales personnel. The number of salaried personnel varies with the size and complexity of the plant and can range from three or four to many times that number. Some plants are run at night and on weekends entirely by foremen, with the superintendent and engineers on 24-hour call to handle emergencies. 

For analytical purposes and an initial characterization, quick tests (duration minutes to few hours) are sufficient. However, the estimation of the usefulness as an industrial material needs long-term testing (months to years) in different environments (air, water, solvents, etc). The numerous other tests employed in engineering practice to determine mechanical (and other) properties, as well as the special methods for testing rubbers, films, fibers, foams, coatings, and adhesives, will not be dealt with here. 

In 1992, researchers developed an engineering and costing design for a fixed unit that operated at a rate of 2 tons per hour. Costs were estimated to be 149 (Canadian) per metric ton of soil treated. This estimate was based on the following assumptions the unit used medium naphtha as a solvent operations were 24 hours per day, for 260 days per year utilization factor of the facility was 83% capital costs were 2,548 million (Canadian) and capital amortized over 10 years at 10%, two payments per year. The estimate stipulated that the recovered oil was of suitable quality to be sold to offset process costs. It was estimated that the largest component of process costs would be labor ( 56 per ton of waste treated). Other cost components listed were capitalization costs ( 38 per ton), utilities ( 29 per ton), insurance ( 9 per ton), trucking and maintenance (each 5 per ton), equipment rental and site excavation and restoration (each 3 per ton), and waste disposal was estimated to cost 1 per ton (D17896F, p. 8). 

Thin-layer chromatography (TLC) has been used for estimating the remaining useful life of engine oil including depletion of the multifunctional additive ZDDP. It was found that the soot from the oil did not interfere with the spot intensity since these particles did not travel with the mobile phase. The TLC technique has the potential to be a good supporting technique for estimation of chemical additives depletion (Brook et al., 1975 Coates, 1971). This technique is comparatively easy, very cheap, does not need sophisticated and expensive instruments and takes less than an hour. 

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