Any steam lines rising in the direction of flow should slope at not less. Taking flash steam into consideration, condensate piping has to be sized based on twophase flow the presence of steam and condensate. The steam pressure is the expected minimum steam pressure. Hot tapping hot taps can be performed on most any type of pipe, ranging from carbon steel to pvc. From a simplistic standpoint, the best pipe size is obviously the smallest size that will accommodate the application at hand. Steam pipe sizing is easy with todays sizing programs. Commercially made expansion joints take very little space and are generally not too expensive in this size. Basic steam pipe sizing charts xylem applied water systems. Plant engineering five common steam line sizing errors. From a realistic standpoint, optimum pipe size can have many meanings with proper consideration of the application. Process piping fundamentals, codes and standards module 1. This design guide addresses the steam tracing requirements of piping and equipment by matching the heating requirements with the type of steam tracers best suited for that application. The steam pipe sizing can be done on the basis of two methods namely. Example for steam pipe chart, pounds per minute to pressure drop.
Not only must steam traps be piped off the bottom of the steam lines, the pipe must be properly sized. Pipe sizing is a crucial aspect of steam system design. When using a sizing program to select steam pipe sizes, the engineer or contractor is asked to fill in the capacity, the steam pressure, and the velocity required. When boiler pressure is lowered, a lower stack temperature results. A frequently used rule of thumb assumes that the design length of pipe is 50 to 100% longer than actual to account. The din 2448 pipe grade corresponds to the en 10220 pipe grade for this calculation.
Loop sizes are taken to the nearest half foot on the height and width. Drip legs are vertical piping pockets located along the steam main pipe where condensate is collected for the purpose of draining from the system. Use pipe size tables to find a pipe diameter for the pipe schedule being used. Sizing steam traps how to determine the proper size trap capacity tables that follow show maximum discharge rates in pounds per hour. This can be accomplished by preparing the steam piping before the steam piping has been installed or by conducting controlled steam blows after the installation. Support locations are dependent on pipe size, piping configuration, the location of heavy valves and fittings, and the structure that is available for the support of the piping. Taps are done on lines containing water, oil, gases, fuels, steam, and many other chemicals. Pipes and pipe sizing spirax sarco first for steam. Pipe sizing two principal factors determine pipe sizing in a steam system. Economic sizing of steam piping and insulation journal.
Pipe sizing steam supply and condensate return lines sizing charts chart cg25, page cg51, is the basic chart for determining the flow rate and velocity of steam in schedule 40 pipe for various values of pressure drop per 100 ft, based on 0 psig saturated steam. Correct sizing eliminates water hammer, pipe erosion, and long startup times. There are a number of piping standards in existence around the world, but arguably the most global are those derived by the american petroleum institute. The flow condition, whether turbulent or not, will determine the method used to calculate the friction factor.
This chart provides a simple method for sizing steam pipes with velocities in the range of 7,000 to 10,000 ftmin. Steam pipes can be sized with the table and diagram below pressure in bar, velocity in ms and capacity in kgh sizing steam pipes imperial units. Design rules for steam condensate systems masters thesis 2017 87 pages, 49 figures and 4 tables. Sizing steam pipes imperial units lbh steam pipe sizing diagram kgh. Trevithick was the first to successfully use highpressure steam then known as strong steam. Although the example covers calculating pressure drop, it is possible to work backwards to calculate pipe size, given pressure drop. Appendix at the end of this module pdf can be determined by finding the pressure factors f1 and f2. Opportunities and issues varies directly in proportion to the boilers net stack temperature the difference between the flue gas temperature and combustion air temperature.
Outside diameter od remains same for a given size irrespective of pipe thickness. Pipe sizing steam supply and condensate return lines. This, in turn, causes slightly improved combustion efficiency. Pipe sizing nomogram pipeline products for all industries stauff anglia limited 405 coppersmith way wymondham norfolk nr18 0wy e. The steam generating facility, located in the boiler room, consists of boilers, feedwater systems, heat exchangers e. See pipe data charts on pages 305 thru 311 for proper size selection. No firm rules or limits exist which will positively fix the location of each support on a piping. Online calculator to quickly determine pipe sizing by velocity for steam. Dimensions shown in parentheses are in millimeters unless otherwise. This is when the piping requirements are defined such as desired working pressure, maximum pressure, maximum flow rate, acceptable pressure drops and classification requirements. The steam system must be clean and free of any dirt or sediment before commissioning the steam system with a safety valve. Steam piping systems an overview sciencedirect topics.
Values from weightflow rate and velocity of steam charts automatically considered no need to look up information. After determining the condensate capacity and internal condensate discharge orifice size, then select the steam trap pipe connection size to. To select the correct size trap from these tables, the normal condensing rate should be converted to a pounds per hour basis and multiplied by a safety factor. A portion of the pipe will be occupied by flash steam and the balance with condensate. This slope will ensure that gravity and the flow of steam, will assist in moving the condensate towards drain points so that the condensate may be safely and effectively removed see fig. For example, a 5 psi system should not have condensate lines higher than 10 feet above the steam trap. Koppl uses the latest technology in coupon retention available. One pipe parallel downflow system a operation b downfeed riser piping c pipe sizing g. All the steam flows above a given colored line are less than the velocities shown in the tables. The answer is a pipe size and a pressure drop per 100 feet of pipe. The steam system piping recommendations that follow are designed to help guide an individual working on existing systems. Steam piping figure 1 allows pressure drop to be calculated given saturated steam pressure, flow rate and pipe diameter. The information contained in this design guide will take the reader through a stepbystep procedure to make proper steam tracer selections based on. Pipe sizing sizing steam and condensate pipes pressure loss, recommended velocity, capacity and more.
Gas constants gas flow constant c for sonic flow steam sizing k c k c 1. The optimum pipe size optimum pipe size denotes the best pipe size. Lanl engineering standards manual pd342 chapter 17 pressure safety section d20b31. For dry saturated steam lines, the velocities considered range between 2535 ms. An introduction to steam generation and distribution. Steam is a compressible gas where mass flow capacity of pipe lines depends on steam pressures. Va standard details div 23 hvac steam all details 1 of 2. Steam system design and best practices related to kiln drying. The hydraulic piping standard handbook assists in the above mentioned engineering process by providing relevant information and standards for this project input phase. The velocity ranges shown in steam pipe capacity tables 451 through 464 can be used as a general guide in sizing steam piping.
As an example a bleeder steam line that delivers 55,300 lbmhr 7 kgs at 93. Allows easy calculation of flash steam loss and associated energy cost through a failed steam trap. Once the steam main is up to operating temperature, the rate of condensation is mainly a function of the pipe size and the quality and thickness of the insulation. The capacity is simply the maximum flow rate in pounds per hour or pph. Steam velocities of 25 ms are in general sufficient. A general rule of thumb is that 1 psi of steam will raise water about 2 feet. Steam lines should ideally be arranged to fall in the direction of flow, at not less than 100 mm per 10 m of pipe 1. From there trace a line vertically upwards and simply read off the pipe size, which in this example would be 32mm. The friction factor will be dependant on the pipe size, inner roughness of the pipe, flow velocity and fluid viscosity. Extra care should be taken for expansion stresses due to the higher coefficient of expansion for stainless steel. Design of steam heating systems an introduction to the basic design of steam heating systems. All other components will be threequarterinch 34 pipe size minimum.
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