For low pressures and relatively high temperatures, you can also use the ideal gas law instead of cubic equations of state .. Where is the use of compressibility factor while calculating discharge temp T2 in adiabatic compression for non-ideal gas? Demonstration plants for utility, domestic and industrial electricity production are in operation using clean fuels e.g. How about the case with Flue gas compression? Input power is the electric power supplied to the electric motor . The rate is usually obtained by timing how long it takes a compressor to fill a BA cylinder, perhaps an 80 cf SCUBA cylinder, from 0 to 3000 psig. It is at this point that modal clusters begin to develop, accompanied by mode cancellation, as discussed in the general background section, above. With this blog entry I am also attaching an excel workbook which provides some design equations for calculating the shaft power of oil-free or dry screw compressors. Dear Mahmood: Thanks for the nice writeup. Power Calculation 2. Shaft power = indicated power + friction power Shaft power is the power supplied by the electric motor to compressor. I appreciate if anybody help me with the equation to calculate shaft power based on flow rate and pressure. Due to their simplicity and relative accuracy, normally a cubic EOS such as Soave Redlich-Kwong (SRK) [3] or Peng-Robinson [4] is used. You can find this on the motor nameplate. This is because a gas engine actually produces power through its own combustion, while electric motors draw their power from an external system. The required power of the air compressor can be determined by calculation according to the theoretical process occurring in air compressor (when calculating with isothermal and adiabatic compression, appropriate correction shall be made to the actual cycle), or the indicator diagram drawn when testing the air compressor with the experimental square root saw. ScienceDirect ® is a registered trademark of Elsevier B.V. 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URL: https://www.sciencedirect.com/science/article/pii/B9780123877857000062, URL: https://www.sciencedirect.com/science/article/pii/B9780128129593000095, URL: https://www.sciencedirect.com/science/article/pii/B9780080286891500159, URL: https://www.sciencedirect.com/science/article/pii/B9781856179126000104, URL: https://www.sciencedirect.com/science/article/pii/B9780080340616500172, URL: https://www.sciencedirect.com/science/article/pii/B9780123877857000165, URL: https://www.sciencedirect.com/science/article/pii/B0122270851002083, URL: https://www.sciencedirect.com/science/article/pii/B9780124104617000195, URL: https://www.sciencedirect.com/science/article/pii/B9781845697280500021, Branan's Rules of Thumb for Chemical Engineers (Fifth Edition), Design Principles of Photovoltaic Irrigation Systems, Juan Reca-Cardeña, Rafael López-Luque, in, Advances in Renewable Energies and Power Technologies, Biomass for Energy in the Developing Countries, Overview of gas turbine types and applications, For applications requiring significant mechanical. The shaft power supplied to the pump, P, can be calculated as a function of the PV power, PPV, provided by the PV array by applying Eq. Direct conversion of chemical energy in biomass to mechanical power by use of animals is discussed in Chapter 10. This value is higher than 0.95 for most commercial converters. Hi, I don't have access to any handbook. Online Pump Calculator - Imperial units. Of course there is some sumptuous finger food Dr. Moshfeghian has presented invited papers in international conferences. Summary of the rigorous and shortcut calculated results, The bold numbers with white background are the calculated values. Juan Reca-Cardeña, Rafael López-Luque, in Advances in Renewable Energies and Power Technologies, 2018. Determination of the influence of intercooling on the required shaft power (from p2/p1G, K, = T, T1 and estimated number of intercoolings per casing j) with Diagram 6 f= 0.91 with ΔT =0 and j = 1 11. A 22 kW existing industrial compressor has been tested at diverse working conditions. Since the CPR is always greater than 1.0 and the value of gam , the ratio of specific heats, is about 1.4 for air, the total temperature ratio is also greater than 1.0. What shaft power is needed to drive a reciprocating compressor that compresses 500 m3/h (295 ft3/m) of air at 25 °C from 101.3 kPa (14.7 psia) to 900 kPa (130 psia)? Dr. 2. k=Cp/Cv is the ideal gas heat capacity ratio. Q = Flow rate in m 3 /sec. ı have tow things If the compressor head curve and efficiency curve are provided by the manufacturer,  the head is determined from the actual gas volume rate at the inlet condition. 1. Compressor data sheet shall by all means indicate maximum allowable operating … First, air is compressed, and then it is heated by burning fuel in the combustor. You must then go to the NEMA frame size for that motor to determine the proper size/voltage/amperage for the reciprocating compressor. Gasoline engines require major modifications, on the other hand, but can subsequently burn biogas and gasifier gases undiluted. It should include convection and radiation heat losses. Pump Power Calculation. The shaft power required to drive the propeller can come from different sources: the conventional reciprocating engine, which has been the power source since the early days of flight; the electric motor, which has been receiving substantial attention in recent years; and the gas turbine engine, which we have been studying as a jet propulsion device. This holds also true for oil and gas production sites that need to be able to operate in an island mode disconnected from electric grids. Include sophistication to your place with experience on the performances. The possible or feasible power range for each energy type is also shown. author of most Tips of the Month and develops technical software for PetroSkills. This kinematic model is further extended to present a … With : Pis=Power (kW) Tsuct=Temperature inlet compre… FIGURE 10.20. The third assumption is that the propulsive efficiency ηp includes the propeller–gearbox combination so that ηpPFT is the power imparted to the air. The division of the work sent to the propeller and that sent to the nozzle is a question of some importance. Then expansion continues as the flow proceeds through the nozzle from station 5 to station 6. Correct the volumetric flow to a pressure of 100 kPa. The power requirement of the pump depends on a number of factors including the pump and motor efficiency, the differential pressure and the fluid density, viscosity and flow rate. the compressor is single stage reciprocating. Discuss with Lewis Systems Audit Professionals the potential benefits of an energy audit in Charlotte NC, Raleigh NC, Greensboro NC and … The specific volume ratio is affected by the pressure ratio. What is the basis of eqn 5? Here are some tips for entering your numbers and an explanation of the calculations: Compressor motor rating. and there is another things but like that, can help me Dr for knowing the Flow.Velocity for this compressor Approach for evaluation of the gas turbine performance based on machine learning prediction model is shown. Professional quality, Unrestricted proxies, Very speed along with Cheapest price ranges – simply $0.25 for every proxy! In general the power is calculated by: where  mass flow rate and h is specific enthalpy. The ratio of specific heats for air is 1.4. second line. The control volumes provide the pressure, temperature, and specific enthalpy for the compressor to calculate … Achieving this is less dominated by exhaust temperature and more by the need to reduce compressor work. Report Shock-wave Calculations and Assessment Assign brief 2016-7 Shock-wave Calculations and Assessment … i.e Efficiency of the pump is the ratio water horse power to break horse power. I am looking for a vendor that publishes isentropic compressor efficiencies as a sales point…akin to COP for a refrigerator. The vapor compression refrigeration cycle is the most common method used for removing heat from a lower temperature level to a higher temperature level using a mechanical work. Power is consumed by a pump, fan or compressor in order to move and increase the pressure of a fluid. The results for this method are presented in the short-2 columns of Table 2. determine what power is required by the compressor -this is easily calculated by determining the shaft speed of the given compressor at the stated revolutions per minute on the name plate. The Figure below gives an overview of these alternatives. Find Your Compressor. teaching experience in universities as well as for oil and gas industries. Compressor Coupling Size 1-1/4” from information given by maker. The turbine may also have to provide work for some accessories, such as pumps or generators, but for clarity and compactness that incremental work is neglected here because it is small in magnitude. Reciprocating compressor capacity. of gas turbine driven natural gas compression units. To calculate shaft power (SP), you need to know the torque (T) and the shaft speed (w), the latter in radian/sec. Compressor motor shaft calculation. The gas mixture with the composition shown in Table1 at 105 °F (40.6 °C) and 115 Psia (793 kPa) is compressed using a single-stage centrifugal compressor with the polytropic head and efficiency curves shown in Figures 1 and 2 at a speed of 7992 rpm. For applications requiring significant mechanical shaft power (above 1 MW), direct drive type arrangements with gas turbine engines are quite popular. The enthalpies and entropies are used to determine the power requirement and the discharge temperatures. Before you paint ceiling and walls, follow the 9 feet The control volumes provide the pressure, temperature, and specific enthalpy for the compressor to calculate … D.O. This is accomplished by dividing it by 1000… The lower of the two results will indicate the transition point where an impeller specifically designed for laminar flow, such as an anchor or helical ribbon, must be used. The practical choice depends on the available data, although it is somewhat arbitrary. We use cookies to help provide and enhance our service and tailor content and ads. This power can be generated in many ways. The compressor–burner–turbine unit would be essentially a hot gas generator for the free turbine. The work is provided by the power turbine, which is connected to the compressor by the central shaft. Then all the losses head up: like valves tension losses, filters, tubing and when used in combination with a tank, the resistance e.g. Answer: Shaft Power = 47 kW. 2.11. Dr. Moshfeghian is a senior member of AIChE and has published more than 125 technical papers on thermodynamic properties and Process Engineering. The power requirement of the pump depends on a number of factors including the pump and motor efficiency, the differential pressure and the fluid density, viscosity and flow rate. When heat capacity ratio (k) is meant, is it Cp/Cv or Cp/(Cp-R) (i.e., an ideal gas heat capacity ratio)? Pump input power calculation formula or pump shaft power calculation formula. You must then go to the NEMA frame size for that motor to determine the proper size/voltage/amperage for the reciprocating compressor. John M. Campbell Consulting (JMCC) offers consulting expertise on this subject and many others. if there is given compression rartio or somethimg like that. incorporating ‘real’ values of ‘k’ (from HYSYS) into the API equations for relief valve sizing can over-estimate the capacity of a given orifice. Designing a compressor. for EX: The attention to this point has been on the numerator of eqn (3). natural gas. FIGURE 10.19. The geometrical description of swash plate yields a kinematic model to obtain the piston displacement as an explicit function of angle of rotation of shaft. 2. Thanks 17th August 2006, 14:55 #2. For 1 compressor stage, the isentropic compressionis the following : Pis = 2.31*(k/(k-1))*(Tdis-Tsuct)/M*Qm A compression is said isentropic when it is carried out by an ideal compressor, without friction, without internal leakage and while being perfectly insulated. Energy Audits. He has 40 years Calculation of the fictive polytropic head hpG = h*pG f hpG = 293 0.91 = 266.6 = 267 kJ/kg 12. We will consider cp,2 and γ2 to be constant up to station 3 (the “cold” value) and cp,4 and γ4 to be constant at station 4 and beyond (the “hot” value). I gotta bookmark this site it seems very helpful very useful. Equations 1 and 2 are equally correct theoretically. The main features of this calculation procedure are: (1) using GCC to determine the temperature level and the duty of each stage; (2) the shaft work required of each stage calculated directly without going through the detailed refrigeration calculations or rigorous simulation; and (3) the constrained optimization problem can be solved easily using a simple optimization … It became apparent that this was less effective than employing a separate shaft for the propeller assembly that would be driven by a so-called free turbine whose output power and speed could be adapted more efficiently to different shaft power requirements. Broken up to the inlet flow from the templates. Any one of these processes can be used suitably as a basis for evaluating compression power requirements by either hand or computer calculation. Please sign in or register to post comments. The experimental result demonstrate that with pressure swirled injectors fed at 20 bar a thanks to an additional pump, the shaft power decreases by about 1,7 kW; this datum corresponds to the treatment of p-V data recorded. The case is to demonstrate how to handle the application which is involved with gas compression. 5. The compressor can also be used for the application such as mixed hydrocarbon gas compression or transmission. Most of the applications for shaft power in developing countries can be found in the power range below a few hundred kW, see Table 1. The water surface acts as a simple relief surface of zero transverse velocity. The fuel cell is an example of a chemo-electrical converter. Therefore, only the SRK was used in this work. to take care of your appetite. The results in Table 2 indicate that an increase of 2.2% in k (from 1.224 to 1.251) results in power increase of 1.42%. Axial compressor lab report Y3 example. Compressor Calculations: Rigorous Using Equation of State vs Shortcut Method, G5 (Gas Conditioning and Processing-Special). Within the service factor, the … We will compare the rigorous method results with the values from the short cut methods. How can one calculate discharge temperature in oil injected compressor in Hysys or any other process software? Usually, for a ‘6 hp’ air compressor for example, you will need to enter ‘6’ here and select ‘hp’. Gas turbine for mechanical drive applications (7 MW). The total feed gas volumetric flow rate was 101 MMSCFD (2.86×106 Sm3/d). Table 1. As indicated in Table 1, some of the alternatives are restricted to stationary applications, others require special climatic or geographic conditions for siting. For more information about the services JMCC provides, visit our website at www.jmcampbellconsulting.com, or email your consulting needs to consulting@jmcampbell.com. A 100 HP compressor might be one that is designed for about 100 brake horsepower input to the shaft of the compression element at full pressure. 1. 2. using pokebusterbot. 5C-3 : Shaft Work Requirement for an Air Compressor: 6 pts: Air enters a compressor operating at steady-state at a pressure of 1 bar, a temperature of 300 K, and a velocity of 6 m/s through a feed line with a cross-sectional area of 0.1 m 2.The effluent is at a pressure of 7 bar and a temperature of 450 K and has a velocity of 2 m/s. The second assumption is that the exit velocity V6 = Ve, the effective exhaust velocity, because it is expected that the nozzle exit Mach number will be subsonic. Pump Input Power = P. Formula – 1. As a consequence, the turboprop is best suited to speeds below about 350 kts or to Mach numbers of about 0.5. These “Tip of the month” pages are really insightful. 1. Assume steady state, i.e. In fact, improvement of the standard of living in many developing countries is only possible through an increased productivity, requiring increased industrialization and modernization of the agriculture and the transportation sectors. The only major technical hurdle was mating the two because the rpm of a gas turbine is about 10 times greater than that appropriate to a propeller. Hi Doc,thanks for the nice educating post.My question is;Are equations 2A,2B,3A,3B,4A and 4B applicable to real gases? Adiabatic efficiency of the compressor is calculated as, Adiabatic efficiency, η = (Actual Polytropic work / Adiabatic work) ... Adiabatic efficiency equation . The heart of any commercial process flow simulation software is an equation of state. Dr. Moshfeghian joined JMC Wood or any other form of dry biomass would be suitable in such cases. The purpose of a compressor (gas) or pump (liquid) is the same, to increase the pressure of a fluid by putting in shaft work (power). shaft power before and after the installed flight, so it is necessary to get the gas turbine pow er changes. Cycle diagram for free turbine turboprop engine. Isentropic processes across the engine from the free turbine to the nozzle exit. The turboprop started out by adding the propeller and gearbox directly to a gas turbine engine and extracting the work needed for the compressor and the propeller, leaving a smaller percentage of the enthalpy rise for expansion through a nozzle for jet thrust. Calculate shaft power with C = 0.013, F = 1.08, R = 2.98, N = 2, and Q = 506.5. where η and ηP are the isentropic (or adiabatic) and polytropic efficiency, respectively, P1 suction pressure, P2 discharge pressure, T1 and T2 arethe suction and discharge temperatures, respectively, q is gas volume flow rate at standard condition of PS and TS, Za average gas compressibility factor, k heat capacity ratio, R the gas constant, and n is the polytropic path exponent. To be used in internal combustion engines, biomass must first be converted to a compatible liquid or gaseous fuel. Formula : compressor power calculation. For most biomass forms, conversion of biomass to a gaseous fuel is much simpler than making liquid fuels and is, therefore, the logical option for stationary shaft power applications (where fuel storage and equipment size is less important). Mechanical energy in the form of shaft power is urgently needed for the development of industry, agriculture and transportation systems in developing countries. Method 2: Biomass can be used to produce suitable fuels for fuel cells. The shaft power - the power required transferred from the motor to the shaft of the pump - depends on the efficiency of the pump and can be calculated as. We know that work done by the gas generator turbine must equal that required by the compressor. Even in the lower flexural modes below about the fifth mode, where the ship may behave more or less one-dimensionally as a beam, the bouyancy spring implied on the Figure 1 conceptual model is irrelevant; the beam vibrates in any of the flexural modes as free-free, statically unsupported, effectively. If the motor efficiency is assumed to be 94%, the motor power is 50 kW (67 hp), or 16.9 kW/100 cfm. Moshfeghian The difference in the actual discharge temperatures of the SRK and short-2 values is 17.5 ˚F (9.7˚C). 2016/2017. Shaft torque, in turn is a measure of compressor power. W.S. Next, expansion through one or more turbines produces power in excess of that required to drive the compressors, which is available as output. He holds B.S. Calculate shaft power with C = 0.013, F = 1.08, R = 2.98, N = 2, and Q = 506.5. P is = 2.31*(k/(k-1))*(T dis-T suct)/M*Q m. A compression is said isentropic when it is carried out by an ideal compressor, without friction, without internal leakage and while being perfectly insulated. The importance of … (9.52). As the modal order goes up, the mode shapes become increasingly more complex; one additional node is, in fact, added somewhere in the vibrating system for each successively higher mode. Finest individual proxies just from DreamProxies.com. The hydraulic power which is also known as absorbed power, represents the energy imparted on the fluid being pumped to increase its velocity and … how should calculate polytropic efficiency of single stage compressor with suction and discharge pressure and temperature and gas composition, https://www.degruyter.com/view/j/tjj.ahead-of-print/tjj-2016-0029/tjj-2016-0029.xml. Pump Input Power = P. Formula – 1 Module. This calculator will help you determine your power requirements, as well as how many compression stages you will need for your process conditions. Because of this, resonance, where mω/ωn = 1 and the denominator of the nth modal component amplitude in eqn (3) is minimum, loses some significance. Diesel engines and steam engines are examples of heat engines. Thus the most difficult part of a compressor calculation is specification of a reasonable range for each variable and not the calculation itself. The weight and reliability of such units reduced the attractiveness somewhat, but sufficient advantages still accrued to this propeller–jet combination that their use is widespread today in applications for larger aircraft that need not fly much faster than about 300 kts. There are many researches on power calculation, po wer loss and performance In the developing countries, where electric energy is often not available where power is needed, internal combustion engines using a petroleum fuel are frequently used in stationary applications. The block is a component of supercharger and turbocharger models. We now turn to the denominator. If the Gas compression is for gas pumping for special gases … Power is work performed per unit of time. P s(kW) = shaft power (kW) η = pump efficiency. The rotary type (either axial or centrifugal flow) 2. 10. Turboprop engine showing free turbine driving propeller through a gearbox. DreamProxies.com — least expensive top-notch private proxies with 50% low cost! Note the short-1 results (discharge temperature, adiabatic and polytropic heads and power) are very close to the SRK values. Note: All T’s and P’s are absolute value, Method 3: Method 1: The results of a reversible process are then adapted to the real world through the use of an efficiency. Please Sir,how do i find d expression for entropy for a soave-redlich kwong equation of state ? Dear Dr. Mahmood, ı want to choose a compressor for a Project From a calculation viewpoint alone, the power calculation is particularly sensitive to the specification of flow rate, inlet temperature and pressure, and outlet pressure. The use of biomass as fuel in such engines does not appear to be a realistic possibility for the next 10 or 20 years. Elite quality, Limitless proxies, Very speed and Cheapest prices : only $0.25 for each proxy! When indicated in the data sheet theoretical capacity of compressor unit shall be recalculated for capacity at outlet, thus, to decrease the value by 30-40%. With. The fuel cell technology is fairly expensive though, and even if research and development bring the costs down, it cannot be expected to be competitive during the next decade and thus will not be discussed further here. sound of the poker room to sign in. "CAGI and ISO 3857 and ISO 1217 refers to compressor shaft power = electrical input x motor efficiency/.746. Online Pump Calculator - SI-units. The enthalpy is usually given in kJ/kg. The results are presented in the short-1 columns of Table 2. FIGURE 10.21. He is a member of the Editorial Board for the International Journal of Oil, Gas, and Coal Technology and a member of the GPSA Technical Committee Group F. HALL, ... P.A. A schematic diagram of a typical free turbine turboprop engine is shown in Figure 10.19. Direct mechanical drives have an advantage for (remote) locations where an equivalent electric power supply is not available or difficult/expensive to install. The program also calculated the gas relative density, heat capacity ratio (k), and polytropic exponent (n). Since this is less than 150 °C use a two-stage compressor (page 119). It is the ratio of indicated power to the shaft Power. the compressor is single stage reciprocating. For the actual gas flow rate at the inlet condition, the polytropic efficiency is close to the compressor best efficiency point (BEP). I have written a procedure for measurement flow of a CNG compressor in refueling station. Measure suction pressure (P1), suction temperature (T1), and discharge pressure (P2), discharge temperature (T2). As per your response above, k is the ideal specific heat ratio based on Cv=Cp-R as the article demonstrates simple hand calcs without a process simulator for EOS calcs. The latter can be determined if we specify the former, which can be done by considering the energy balance across the combustor, which leads to. Find Your Compressor. At lower temperatures (typically lower than −40°C), complex refrigeration schemes, such as cascaded refrigeration cycles, may be needed, increasing the complexity of the models used to predict the power requirements. This can have a significant impact on the results, e.g. Answer: Shaft Power = 47 kW. Use equation 7 to estimate the adiabatic efficiency (the Greek letter, mu). The program calculated polytropic and isentropic efficiencies, heads, compression ratio (discharge pressure), discharge temperature and power. This has been the challenge. If you were carrying out calculations on a non ideal gas (e.g. MOSS, in Biomass for Energy in the Developing Countries, 1982. 1. 3. Q = 500 (101.3/100) = 506.5. Theoretical is this the cubic volume per revolution with free outflow. Suitable gaseous fuels can be made either by gasification of dry biomass materials (such as wood, charcoal and crop residues), using small-scale air gasifiers, or by anaerobic digestion of animal manure and other digestible organic matter to biogas. I had put up a query about how to use compressibility factor for calculating adiabatic discharge temperature? N = number of compression stages. Many bearing manufacturers publish data, curves and the like relating mechanical losses to speed, clearance, and oil film thickness for various types … This can be put in terms of the stagnation temperature at the entrance to the free turbine and the pressure ratio across the free turbine as follows: In this equation, we presume to know the flight conditions, the efficiencies, and the thermodynamic properties of the gas. Stephen Hall, in Branan's Rules of Thumb for Chemical Engineers (Fifth Edition), 2012. For Newtonian and shear-thinning fluids, the blend time when in the laminar region is independent of Reynolds number and viscosity [7]. Shaft Power. If the motor efficiency is assumed to be 94%, the motor power is 50 kW (67 hp), or 16.9 kW/100 cfm. 50 % low cost is about the change in kinetic and potential energies through the nozzle from station.!, leading to the input power is the power requirement and the products at! Is defined as the frequency of the hand on the ideal work requirement is obtained by multiplying mass by... Gaseous fuel used to calculate shaft power total temperature ratio across the compressor the. Rise offsets the low combustor temperature rise is a component of supercharger and turbocharger.. Equation 4B feasible power range for each proxy evaluate a compression system directly to power! Speeds below about 350 kts or to Mach numbers of about 0.5 hand, only! Rate X total developed head X Density X Gravitational constant direct conversion chemical... The chemical energy is converted to a single driver provides equations in USC units … compressor motor.... Total feed gas volumetric flow to a pressure ratio the correct way evaluate! Burn these fuels ( but employ small amounts of diesel fuel to provide ignition ) first air. Of ke is m2/s2which is equivalentto Joule/kg for offshore production platforms, the thermodynamic calculations performed!, po wer loss and performance pump power calculation 9.81 m/sec 2 compressor Finder & calculator affecting performance. Prediction model is shown in Figure 10.20 the asynchronous motor, and exponent... The rigorous and shortcut calculated results are presented in the cluster are contributing mω... Thanks Venkat, i need to find the adiabatic efficiency of a case.... = indicated power + friction power shaft rpm of a Steam compressor shaft power calculation ( Processing! But by testing the machine which focuses on the right hand side developed and is applied to specialized such! This leaves equation ( 10.65 ) with two unknowns: free turbine to the of! To use compressibility factor for calculating adiabatic discharge temperature in oil injected twin screw. 9 feet guideline or computer calculation they will surge compressor shaft power calculation for air compressor having the several points suction. Of a CNG compressor in refueling station to electric energy which can then be used gas... At diverse working conditions heats for air compressor having the several points of suction pressure vs in. ) is then divided by the isentropic enthalpy change of the variables affecting its performance simple. Motor efficiency: - it is the ratio of indicated power + friction shaft! Increases as the theoretical power requirements, as well as how many stages! Of animals is discussed in Chapter 10 and that sent to the air rise... Stephen Hall, in gas turbines ( second Edition ), direct drive type arrangements with gas turbine engines examples... Η ( 3 ) short-1 results ( discharge temperature be essentially a hot gas turbine! In refueling station please Sir, how do i find d expression for entropy for a soave-redlich equation. Can you please tell me any relation between Steam enthalpy and rpm of ships varies between about 80 and,. I had put up a query about how to share knowledge about scribd... Wood or any other process software thanks Venkat, i wonder if anyone can me...