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How Much Cost A Cement Grinding Unit House How Much Cost A Cement Grinding Unit House The average cost to install a concrete slab is 6 20 per square foot In addition to the cost of the concrete itself there are also labor costs for preparing the area the ...

Clinker Grinding Unit Of Cement Plant Cost In India. Posted by on May 09, 2018. Clinker Grinding Process In Cement Manufacturing Unit. Clinker Grinding. Coal grinding and burning is one of the most integral parts of cement manufacturing.

Cement Mill Rotation Speed: 0.15 r/min Production Capacity: 21-155TPH Product Specification: 1.8374.614m Details Cement Grinding Plant Feeding Size: 25mm Production Capacity: 200t/d-8,000t/d Technological Features: Crushing raw materials, pre-homogenizing materials, arranging ingredients, efficient grinding, homogenizing materials, suspending pre-heater and .

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Cost Cement Grinding Unit Burkina Faso This plant will be followed by the commissioning of another grinding unit in Jhajjar Haryana later this year with both projects representing a total investment of INR8bn US112.09m. Grinding mill for cement production ...

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Horizontal mini-cement grinding mill with belt conveyer system, crushing pulverising unit without motors, used for two years only in 1999, production capacity 250 bags per shift of 8 hours Disposal Cost: 5 Lac Above equipment available at Meerut, U.P., India.

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cement factory cost | how much does it cost to start a cement plant?

If youre thinking about set up a cement factory (or cement plant), you must weigh the pros and cons of it many times. There is no doubt that youve considered all your musts, such as locations, cement plant design, cement plant layout, etc. But the most important thing is absolutely cement factory cost how much does it cost to build a cement factory? Maybe you also want to know the potential investment you dont see coming.

According to the data we know, the total cost of a cement plant is estimated to be US$ 75 to US$ 100 per ton. One thing to be clear, this is just an estimation, in the real cement plant building, the cement factory cost is affected by various factors, including the significant difference in cost of land, availability of limestone mines, etc.

The cement factory cost is based on changing factors like size, location, labor, raw materials, and current real estate trends, which make it impossible to nail down a perfectly accurate, one-size-fits-all answer. So lets list the cost item needed in building a cement factory, everyone can get your own plant according to these items.

As we all know, the cement production line is made up of various types of cement equipment, the cement factory cost depends on the cement factory machine you choose. For some buyer who has abundant funds, might choose high-quality equipment, which increases the cost of the cement production line. At the same time, high-quality cement plant also brings considerable economic benefits and market returns.

At present, the new-type cement plant has advantages of high profit, quick effect, high efficiency, energy saving, environmental protection, easy operation, and low cost. The hot-sale cement plant is composed of following cement factory machines:

If you are ready to buy a cement plant, it is suggested to choose a cement plant manufacturer with a large scale and strong strength, which will provide full cement equipment and service, also ensure the quality and performance. In general, for the customer who wants to buy the whole cement production line, the cement plant manufacturer will give more preferential policies. On the contrary, the strength of small-scale manufacturers is limited, cement equipment types are not complete enough, need to buy from different manufacturers, not only trouble but also increase the cost of investment.

Investors have different requirements for the daily output of the cement factory, so we can find a large capacity cement plant and mini cement plant in the real case, and the investment capital will also be different. Generally, the higher the output value, the higher the investment, because the model requirements for cement equipment will be higher, and the price of equipment will naturally rise, but the value of the benefits to customers will be greater.

Enterprise competition is a side factor that affects the cement plant price. The more intense the competition, the cheaper and more affordable cement equipment prices. On the contrary, if there are fewer cement plant manufacturers and the competitiveness is weak, there is no obvious threat between the companies. Cement plant prices will generally maintain a normal state or relatively increase, which is a manifestation of natural laws.

Except for above elements, there are some other factors involved in the cement factory cost, such as labors, raw materials cost, cement plant design and so on, labors cost is always related to the location and your scale of cement factory; as for the cost of the raw materials, the place where is near mineral resource will be recommended, which will reduce your transportation cost. For most large cement plant manufacturers, they can provide custom solutions to cement plants, also supply the EPC project for equipment or cement plant.

erection equipment - an overview | sciencedirect topics

Two concentric pipes are introduced in a borehole. Fresh water pumped through the inner pipe dissolves and becomes saturated with it. The resulting brine is pumped up the other pipe and then is taken directly to the sea or disposed of in the salt water aquifer.

Equipment erection. In the fall of 1976, equipment such as the unit transformer, generator, etc., started arriving at the plant site. Due to noise limitations, the design called for housing the transformer. The generator stator was lifted to the foundation level with hydraulic jacks. Erection of the equipment continued through the balance of 1976 and during the first nine months of 1977. The HP combustion chamber arrived last. Erection schedule of the major equipment was as follows:

Figure 7 depicts the machine room with the turbo equipment in place. The photo was taken from the compressor end and shows the HP and LP sections of the turbine with their corresponding combustion chambers and, finally, a section of the exhaust stack

Cooling water system. The power plant's cooling system is composed of a four cell induced draft open cooling tower and two main water circuits, each fitted with its own CW pumps. The smaller circuit of about 1100 m3/h capacity serves the unit's oil coolers and the generator coolers. The compressor plant's air inter- and aftercoolers are connected to the larger CW circuit of about 4300 m3/h capacity.

Air piping. Each of two air pipes connecting the caverns with the machine are about 350m long and have a diameter of 609mm o.d. The design conditions (80 bar-80C) appear to be moderate. Nevertheless, thermal expansion and contraction of the pipes results in thrusts acting on the turbine and well connection which had to be resolved.

Air entering the turbine at temperatures below +10C would cause an automatic shutdown to prevent icing in the turbine throttle valves. In order to maintain the required minimum air temperature during standstill, the piping had to be equipped with electric heating cables and lagging.

Measures had to be found to prevent pipe corrosion caused by the humid air. There was no prior experience in combatting corrosion conditions of this nature. On the other hand, no inner coating metallic or plastic could be found on the market that would be effective and stable under all operating conditions, yet easy to handle during pipe-work erection and inexpensive enough to justify the extra expenditure. For these reasons, an extra corrosior allowance of 3 to 4mm was made on the calculated wall thickness in lieu of a coating, and a number of bends and templates were provided with flanged connections to permit easy access to the pipes for inspection. Some of the bends were fitted with inner coatings of different compositions for the purpose of testing.

Plant layout. The installation is a very simple one (Fig. 9). The building has a crane which can service the heaviest piece with the exception of the generator stator. The whole plant is 40 X 20m and has a stack 35m high. The installation is totally remotely controlled over a 100km distance. There are no personnel in the plant.

In the normal operation, the compressor train runs up to synchronous speed of 3000 rpm by means of the turbine, firing only the HP combustion chamber. Starting the turbine, on the other hand, requires a certain minimum air pressure in the underground storage that is sufficient to generate the idling power of the compressor train, about 32 MW, before synchronization. The problem was how to accomplish the very first compressor start with the caverns completely empty. The answer to that problem was: frequency start.

After extensive investigations and preparations, an isolated connection was set up between a 52 MW gas turbine of the jet-expander type in NWK's Emden Power Station and Huntorf through various 110 kV and 220 kV lines and substations, a connection about 90km long. Both units had been fitted with static excitation permitting them to be excited and synchronized with each other while running in shaft turning gear at 80 rpm.

Thereafter, the jet engine gas generators driving the Emden gas turbine were started and the system accelerated to 3000 rpm, at which speed the generator/motor was synchronized with the grid. At this point, the Emden turbine was stopped and the Huntorf compressor train was ready to pick up load.

Mode of operation. No electric power is necessary to start the unit. This is achieved by leading the air to the HP combustion chamber, where it is heated to 1000F and exhausted to the gas turbine. The gas turbine shaft starts to rotate and is, at a certain speed, automatically engaged, through a Synchro-Self-Shifting (SSS) clutch, to the generator. The generator is then synchronized.

These operations are performed by remote control from a 100km distant point at Hamburg. Some 100 controlled points have triple redundancy so to be sure that every order from the load control center goes through without an operator in the plant. If one of the instruments fails, service is dispatched eventually from a 10km distant steam plant to correct it.

Performance. Partial load heat rate. As shown in Fig. 10, the heat rate at partial load of ASSET (WV) is much better than the partial load heat rate of a conventional combustion turbine (WVGT), because with ASSET mass flow is possible, whereas the combustion turbine circulates the same amount of air at all times.

Magnified remote cameras: The computer-based imaging system can provide spatial measurements and surface analysis. It can detect a surface flaw and determine its size, shape location, and defect details.

Developments in data recording: Examples include data loggers, data acquisition systems, and measurement and control products: data recording computer hardware devices include pen-based tablets, and notebook and desktop computers. There is often more rugged hardware available for field use. Techniques to extract data from laser-scan point clouds into 3-D Micro Station drawings have been successful.

The success of ABC is due to powerful equipment. Different erection equipment is required for girders, box beams, trusses, arches, and cable-stayed and suspension cable bridges. Timely availability, a leasing facility, and an experienced erection team will be necessary. Additionally, the contractor will need ready access to long-span freight vehicles to transport assembled bridge components, high-capacity cranes, excavation tractors, torque wrenches, etc. to efficiently transport the subassemblies of bridges and erect the bridge.

The erection contractor may also use robotics, cranes such as tower crane (for maximum lightweight pick of 20 tons and heights greater than 400 ft), lattice boom crawler cranes, mobile lattice boom cranes, mobile hydraulic cranes, and lattice ringer cranes for varying heavyweight pickups. In addition, specialized technologies for the superstructure roll-in and roll-out method using SPMTs have been provided in a recently published FHWA publication, Manual on use of Self-Propelled Modular Transporters to Remove and Replace Bridges.

The success of ABC is due in part to powerful equipment. Different erection equipment is required for girders, box beams, trusses, arches, cable-stayed bridges, and suspension cable bridges. Timely availability, a leasing facility, and an experienced erection team will be necessary.

The erection contractor should utilize robotics, cranes such as a tower crane (for maximum lightweight pick of 20 tons and heights greater than 400 feet), lattice boom crawler cranes, mobile lattice boom cranes, mobile hydraulic cranes, and lattice ringer cranes for varying heavyweight pickups and accessories.

Most of the construction activities for a NPP such as excavation, civil construction, laying of piping, cables and instrument tubing, installation of electrical, air conditioning and ventilation equipment, erection of equipment like pumps, compressors, valves, diesel generators, transformers, switchgear and the turbine generator and its associated equipment are similar to those performed in conventional industries. It should therefore be possible to identify local agencies to carry out these jobs. However, it needs to be noted that the nuclear industry is characterized by stringent quality standards and hence the contracting agencies selected should be capable of performing construction work that meets these standards. The bidding companies should be prequalified and shortlisted based on their work experience, quality of work performed earlier, availability of qualified staff in requisite numbers, and capability to mobilize the required construction machinery and manpower to complete the work according to the schedule. The successful bidders may then be selected from the organizations so shortlisted. There is the modern practice of awarding megacontracts comprising several packages to a single construction contractor. This is towards completing the construction work in the minimum possible time and to minimize paperwork. It would be ideal if agencies for awarding mega-contracts can be identified in the local market. If this is not possible, participation of local sub-contractors under the mega-contract should be ensured to the maximum extent possible. This will not only reduce the cost of construction but also groom the local contractors to take up future NPP construction work in the country. While national participation in construction to the maximum extent possible is highly desirable, there are certain specialized jobs such as the erection of the reactor vessel, primary coolant system piping and reactor control and protection system components that may have to be necessarily performed by experienced vendor personnel. Participation of utility personnel and local contractors in such jobs should be encouraged to the extent possible such that they can utilize this experience subsequently in commissioning and O&M of the NPP and in similar construction activities of future NPPs.

In late 2008 Gamesa Eolica of Spain erected a medium-speed 4.5MW wind turbine G1284.5MW prototype at an R&D wind farm. Key product development goals were maximum drive system reliability and the ability to employ transportation and erection equipment logistics similar to the 2MW Gamesa G8X-2.0MW series. Gamesa's reliability goal resulted in a semi-integrated medium-speed drive system. The Compact Drive drive system comprises a main shaft with two main bearings, a two-stage planetary-type gearbox with 1 37.9 speed-up ratio, and PMG. The generator is directly attached to the gearbox with a flanged connection, whereas the complete drive system is split into separate main components for ease of component exchange.

Besides striving for maximum reliability, additional requirements were optimized systems flexibility and stability, together aimed at setting new standards with regard to Life Cycle Costs (LCC) performance. According to Gamesa, major direct drive system limitations include complex and costly transport and erection logistics due to generator size and weight. These could be avoided by choosing a medium-speed system. Other Gamesa medium-speed drive system preferences include overcoming size and weight issues linked to direct drive, and eliminating the trouble-prone high-speed gear stage of three-stage gearboxes. It was important for the designers not to compromise overall systems flexibility by choosing to eliminate the high-speed gear stage in order to improve reliability.13 Gamesa has also announced, based upon the initial G1284.5MW medium-speed turbine, a 4.5MW version with enlarged rotor and two new offshore-dedicated 5 and 7MW turbines.

To increase accuracy, the cost factors that are compounded into the Lang factor are considered individually. Direct-cost items due to which cost is incurred in the construction of a plant, in addition to equipment items, are the following:

Utilities (services), provision of plant for steam, cooling water, air, firefighting services, inert gas, and effluent treatment (if not in plant costs), for example, lagoons, holding pits, process water supplies.

Table 2-9 shows typical factors for the components of the capital cost, and these can be used to make an approximate estimate of it using equipment cost data published in the literature. In addition to the direct cost of the purchase and installation of equipment, the capital cost of a project will include the indirect costs list in Table 2-9, which can be estimated as a function of direct costs [18].

Other methods for estimating capital investment consider the fixed-capital investment required as a separate unit. These are known as the functional-unit estimates, the process step scoring method, and the modular estimate.

The functional unit may be characterized as a unit operation, unit process, or separation method, which involves energy transfer, moving parts, or a high level of internals. The unit includes all process streams together with side or recycle streams. Bridgwater [19] proposed seven functional units, namely compressor, reactor, absorber, solvent extractor, solvent recovery column, main distillation column, and furnace and waste heat boiler. Taylor [20] developed the step counting method based on a system in which a complexity score accounting for factors such as throughput, corrosion problems, and reaction time is estimated for each process step. The modular estimate considers individual modules in the total system, with each module consisting of a group of similar items. For the modular estimate, all heat exchangers are classified in one module, all furnaces in another, all vertical process vessels in another, and so on. The total cost estimate considers fewer than six general groupings. These are chemical processing, solids handling, site development, industrial buildings, offsite facilities, and project indirects [21]. Table 2-10 gives a more detailed explanation and definition of a functional unit.

A functional unit is a significant step in a process and includes all equipment and ancillaries necessary for operation of that unit. Thus, the sum of the costs of all functional units in a process gives the total capital cost.

Storage in process is ignored, unless mechanical handling is involvedthat is, for solidsas the cost of storage is relatively low and tends to be a constant function of the process. Large storages of raw materials, intermediates, or products are usually treated separately from the process in the estimate.

A number of authors have published correlations based on a step counting approach: Zevnik and Buchanan [22], Taylor [20], Timms [23], Wilson [24], Bridgwater [25], and so on. These and other correlations have been reviewed and compared by Gerrard [3]. Correlations by some of these authors are as follows.

This involves a simpler approach for gas phase processes only, including both organic and inorganic chemical products. The following equations have been updated from the original work by applying an adjusted US plant cost index and converting at $2/ to account for exchange rate and location effects.

Gerrard [3] developed a generalized approach based upon the principle that the capital cost is a function of a number of steps, and basic process parameters, particularly capacity or throughput, can be applied to any special situation to derive a model for that industry or group of processes.

The capital cost includes all equipment, materials, labor, civil installation, commissioning, and cubicle for the control panel. Reagent warehousing would cost about 20% more, and complete enclosure up to 100% more.

Equipment factored estimates (EFEs, Class 4) in Table 2-2 are typically prepared during the feasibility stages of a project, when engineering is approximately 115% complete. They are used to determine whether there is sufficient reason for funding the project. This estimate is used to justify the funding required to complete additional engineering and design for a Class 3 or budget estimate. The first steps when preparing an EFE are to estimate the cost for each item of process equipment, to examine the equipment list carefully for completeness, and to further compare it against the PFDs and P&IDs. However, the equipment list is often in a preliminary stage when an EFE is prepared and even when the major equipment is identified, it may be necessary to assume a cost percent for auxiliary equipment that remain to be identified.

Equipment is often sized at 100% of normal operating duty; however, by the time the purchase orders have been issued, some percentage of over-sizing would have been added to the design specifications. The purchase cost of the equipment is obtained from purchase orders, published equipment cost data, and vendor quotations. It is essential to accurately determine the equipment costs as the material cost of equipment often represents 2040% of the total project costs for process plants. Once the equipment cost is determined, the appropriate equipment factors may be generated and applied by applying the necessary adjustments for equipment size, metallurgy and operating conditions. Tables 2-11 shows an example of an equipment factored estimate, and Table 2-12 shows heat exchanger equipment factors. Table 2-13 summarizes the various factors affecting the capital cost of chemical plants.

Note: The multiplier is the ratio of DFC, TIPC and other costs to the raw total equipment cost of $2,805,000.The cost of each type of equipment was multiplied by a factor to derive the installed DFC for that unit. For instance, the total cost of all vertical vessels ($540,000) was multiplied by an equipment factor of 3.2 to obtain an installed DFC of $1,728,000. The total installed cost (TIC) for this project is $14,387,000.

The cost of each type of equipment was multiplied by a factor to derive the installed DFC for that unit. For instance, the total cost of all vertical vessels ($540,000) was multiplied by an equipment factor of 3.2 to obtain an installed DFC of $1,728,000. The total installed cost (TIC) for this project is $14,387,000.

Applications to precast concrete bridges, precast joints details; use of lightweight aggregate concrete, aluminum, and high-performance steel to reduce mass and ease transportation and erection; availability of patented bridges in concrete; CONSPAN.

Site organization is based on the selection of one general contractor, who in turn selects several subcontractors. Each subcontractor should have experience and must specialize in a particular trade such as concreting, formwork, steel fabrication, bearings, reinforcing steel, etc.

Current specifications do not adequately cover construction-related design and temporary loads. Technical specifications may also be made comprehensive to give the minutest details of the construction loads and application procedure.

The bridge industry is moving to mechanized construction because this saves labor, shortens project duration, and improves quality. This trend is evident in many countries and involves most construction methods. Mechanized bridge construction is based on the use of special equipment.

New-generation bridge construction machines are complex and delicate structures. They handle heavy loads over long spans under the same constraints that the obstruction to overpass exerts on the bridge. The safety and quality of operations depend on complex interactions between human decisions; structural, mechanical, and electrohydraulic components; control systems; and the bridge that is being erected. In spite of their complexity, these machines must be as light as possible. Weight governs the initial investment, the cost of shipping and site assembly, and sometimes even the cost of the bridge. Weight limitations dictate the use of high-grade steels and designing for high stress levels in different load and support conditions, which makes these machines potentially prone to instability. Bridge erection equipment is assembled, operated, decommissioned, modified, reconditioned, and often adapted to new work conditions. Connections and field splices are subject to hundreds of load reversals. The nature of loading is often highly dynamic, the equipment may be exposed to strong wind, and the full design load is reached multiple times (and sometimes exceeded). Impacts are not infrequent, vibrations may be significant, and most machines are actually quite lively because of their great structural efficiency.

Movement adds the complication of variable geometry. Loads and support reactions are applied eccentrically, the support sections are often devoid of diaphragms, and most machines have flexible support systems. Indeed, such design conditions are almost inconceivable in permanent structures subjected to such loads.

The level of sophistication of new-generation bridge construction machines requires an adequate technical culture. Long subcontracting chains may lead to loss of communication, the problems not dealt with during planning and design must be solved on the site; the risks of wrong operations are not always evident in such complex machines; and human error is the prime cause of accidents.

Experimenting with new solutions without due preparation may lead to catastrophic results. Several bridge erection machines collapsed recently with a heavy tribute of fatalities, wounds, damage to property, delays in the project schedule, and legal disputes. Technological improvement alone cannot guarantee a decrease in failure of bridge construction equipment, and may even increase it. Only a deeper consciousness of our human and social responsibilities can lead to a safer work environment. A level of technical culture adequate to the complexity of modern mechanized bridge construction would save human lives and facilitate the decision-making processes with more appropriate risk evaluations.

Hydraulic gates in most cases are entirely manufactured at contractor's locations (fabrication shops), then shipped or otherwise transported to their project sites and installed there. Only very large gates or structures at hardly accessible locations are manufactured and transported in smaller subassemblies. Examples of the latter are the early large rolling gates in Germany and Belgium, large drum gates in US dams (like the Grand Coulee Dam), and the world's largest sector gates of the Maeslant Storm Surge Barrier in the Netherlands.

Some of these gates were not only bolted but also welded together (or riveted like Grand Coulee gates) on project sites due to their unique dimensions. This required longer planning periods and an extensive transfer of fabrication technology, including quality control, to the site. After all, the quality assurance procedures for field fabrication are identical to shop fabrication requirements [1]. One illustrative case of manufacturing, transport, and installation of hydraulic gates in subassemblies was the project of the Rhine River weirs in the Netherlands. The so-called visor gates of these weirs, presented in more detail in Section 3.11, were fabricated in sections as shown in photo (a) in Fig. 5.74. These sections were shipped to the site and assembled there in a new riverbed section that had deliberately been excavated and kept dry for construction purposes (see photo (b) in Fig. 5.74). Most assembly joints were riveted, which reflects the construction technology (late 1950s) of these gates.

Today, the assembly joints of this kind would in most cases be bolted. Proper requirements for splices and assembly connections can, for example, be found in the AISC Steel Construction Manual [66]. The division of responsibilities between the owner, fabricator, and the erector of the steel hydraulic closure should be specified in the contract, based on standard practices in the country of the project. In the United States, such practices make part of the AISC-316 code that is entirely quoted in Ref. [66]. They are further worked out by USACE in Ref. [67]. In Europe, the bases of such practices are defined in Eurocodes 1 and 3; and the details make part of national appendices to these codes or recommendations issued by the national waterway authorities, like Rijkswaterstaat in the Netherlands [55].

These standard practices apply, obviously, also to the scenarios in which hydraulic gates are entirely manufactured and assembled in fabrication shops, then shipped to their project sites and installed there. Such scenarios have many advantages in terms of time, quality, and costs. They form a nearly standard choice in hydraulic projects of today. Transport and installation loads then make part of an erection plan that should mainly contain the following documents:

Documentation and approval reports of auxiliary transport and erection structures to be used, like temporary supports, so-called toasters (see Section 9.6), sea fastening, lifting lugs, spreader beams, and tilt supports.

Transport and erection loads are in the first instance derived from the gate self-weight and the weight of auxiliary structures mentioned above. Yet, some wind loads and (if potentially possible) rain or snow loads should also be taken into account, although gate shipments and erections are normally carried out under good weather conditions. A common practice is to include about 50% of the characteristic values of these loads in the load combinations for transport and erection.

The main component of these combinationsself-weight loadshould in the LRFD approach be taken with a load factor as indicated in Table 5.4. However, this factor does not account for incidental inertial and impact loads that cannot entirely be eliminated during transport and erection. The existing codes also do not specify the magnitudes of these loads, leaving it to the gate erector. This is correct in the sense that safe gate installation is in the first instance his responsibility, but it weakens the position of external control and does not stimulate transparency.

The AASHTO bridge design code [4] states this about the jacking forces for bridges: Unless otherwise specified by the Owner, the design forces for jacking in service shall not be less than 1.3 times the permanent load reaction at the bearing, adjacent to the point of jacking. The loads due to bridge jacking and the risks involved [68] can be comparable to those in hydraulic gate installations.

Manufacturers of heavy steel subassemblies and concrete prefabs use their own, practically proven dynamic factors for the handled weights. Below are approximate ranges of these factors, followed by many European companies in this branch [69]:handlings in shop by stationary cranes: 1.101.30;transport by a lift truck on flat surfaces: 1.301.60;hoisting by a stationary crane on the site: 1.301.50;hoisting by a mobile crane on the site: 1.501.60;transport by a shovel on rough surfaces: 1.602.00;transports under extreme conditions: >2.00.

In the offshore branch, heavy installations at sea are normally engineered with a dynamic factor of about 1.30 over the weight of installed subassemblies. This factor covers possible weather changes but no heavy storms, which normally lead to postponing such works.

These data can help estimating the dynamic factors for transport and erection loads. The reader should not, however, confuse these factors with load factors in the sense of the LRFD method. Note that the factors mentioned here lead only to characteristic values of transport and erection loads including their dynamic effects, like inertial forces and small impacts. As such, they do not contain any safety margin. To provide the required safety in the LRFD method, one should additionally apply load factors G, for example from Table 5.4. In the ASD method, a proper safety factor SF should be applied to the stress that represents the nominal resistance Rn of the structure (see Section 5.1.2).