Steel structure costs

Section 6.5 because of the detailed design information now available. The costing was done in accordance with the recommendations of Mu let, Corripio and Evans (Ref. Al 3). Their method utilizes correlations for the cost of a simple carbon-steel structure. Factors are then applied to account for the cost of other materials, the inclusion of trays, for operating pressure, and for incidentals such as ladders and railings. The cooling circuit was costed on the basis of heat-transfer area using similar correlations. Details of the cost estimation calculations are included in Appendix G.5. 

Figure 8.4 displays the air finfan unit cost in carbon steel materials. This figure includes the cost of the tube bundle, fan, fan electric motor, bundle casing, inlet/outlet casing manifolds, steel structure, stairways, and ladders. Tube pressure rating, material, and labor for both fabrication shop and field assembly are added factors per the associated tables. (See Tables 8.13 to 8.16.)... 

This procedure is used to estimate the weight, fabricated cost, and erection hours of the various types of steel structures required in a chemical plant. It is a very good tool for checking contractors take-offt and estimates as well as discussing and evaluating field extras. 

After arriving at the plant site, construction workers set the equipment in place. This entails placing the equipment on concrete or steel structural supports, prepared in advanced. Because some equipment could weigh tons, a crane will lift the equipment onto supports. Then, construction workers secure the equipment in place. A factor will account for this cost. 

Let us consider the corrosion of metals due to acid rains. Iron and steel structures are highly susceptible to corrosion, and their protection with paint costs billions of US annually. The chemistry of corrosion under atmospheric conditions is extremely complex and is catalyzed by hydrogen ions. This explains why acid deposition causes increased rates of corrosion. Unlike the tightly held oxide film that is formed on aluminum, protecting the metal underneath, iron oxide (rush) provides no such protection to iron and steel. Impurity sites in iron act as cathodes for the reduction of oxygen and the iron acts as the anode... 

The results show that six rows of finned tubes can do the work of 18 rows of bare tubes. Finned tubes are more expensive than bare tubes, but other costs must also be considered such as additional steel structure, refractories and return headers. 

Their use may have a significant impact on the cost of a structure. The cost of the material has decreased in recent years and further reductions are expected, due to new developments in production, but stainless-steel bars are still much more expensive than carbon-steel ones. The following indications can be provided if 1 is the cost of carbon steel bars, 304 austenitic stainless-steel bars costs 6-8, and 316 and 318 (duplex) cost 9-10 [5,6]. 

Cathodic protection of reinforced-concrete structures exposed to the atmosphere was apphed for the first time to bridge decks contaminated by de-icing salts by R. F. StratfuU in California in 1973 [1,2]. In the years following, design and protection criteria were elaborated, as well as power supply and monitoring systems completely different from those used for cathodic protection of buried steel structures or structures operating in seawater. Above all, it was proved that cathodic protection was a rehable repair technique even in the presence of high chloride contents, where traditional systems of rehabilitation are inefficient or very costly. 

LRTM In this process, the upper mould is made from a semi-transparent composite shell, sometimes supported by a steel structure. Advantages include lower tooling costs and shorter production cycles. 

Kleingarn, J.-P. (1978). Costs and duration of protection of the principal corrosion protection schemes for steel structures. EGGA General Assembly, Florence, pp. 48-56. 

Conventional concrete structures, and prefabricated steel structures assembled on site and filled with concrete after placement are used in various structures. Precast concrete modules would also be used. Wide use of removable formwork is employed to limit steel exposure to potential corrosion. Prefabrication of reinforced rebar modules is extensively used. In some places mechanical rebar splices are used to reduce the weight of prefabricated modules. All of these techniques have been employed in previous nuclear power plant construction. Steel structures such as the air baffle, and the containment vessel are constructed of steel panels. Panels are made of stiffened steel or corrugated plate depending on availability and cost panels for the baffle are designed with thermal expansion of the containment vessel in mind. Future inspection and maintenance are taken into consideration. 

A three dimensional seismic isolation system for the reactor building is adopted to achieve the standardization of design. The base size of the building is 40mx40m, and the height is 55m. Shortening the construction schedule on-site is very important to reduce the plant construction costs, thus an optimum combination of steel structure and concrete structure is being considered. 

Light RTM (LRTM) The upper mold half is made from semi-transparent composite shell which may be supported by a steel structure. LRTM was developed to reduce the tooling cost in RTM, and also shorten the labor time of vacuum-bagging in VARTM and thus shorten the cycle time. 

The cost factors which determine the method of manufacture for any particular model are subject to specific local considerations, but there will always be a break even volume below which the necessary investment in presses and press tools for a steel bodied vehicle is unjustified. It is below this qualifying level, which could be as low as 5000, or as high as 100000, that some kind of chassis and space frame construction can be more cost effective than a unitized steel structure. Nowadays, opting for a space frame is likely to be followed by opting, at least in part, for plastic body panels. 

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