One of the limitations of the crane method for determining the equivalent length was the equivalent lengths for pipe fittings and valves in laminar flow regime. Make sure that the valve or fitting you add to the pipeline is for the specific c value of the pipe material. For the availability of 6000psig and 0psig, contact your local distributors. Equivalent length in feet of staight pipe for different. Using equivalent lengths of valves and fittings fluid flow. Table 3 friction losses through pipe fittings in terms of equivalent lengths of standard pipe size of pipe small dia. The nfpa 15 standard has equivalent lengths for valves and fittings based on the type of valve or fitting and the pipe size. These values are defined as the flow rate through the valve required to produce a pressure drop of 1 psi. It is also possible to expand the end of one tube so that it can be joined to another by soldering or brazing without a capillary fitting a procedure. After a pipe diameter has been selected on this basis, the influence of each fitting can be evaluated. This article details the calculation of pressure losses through pipe fittings and some minor equipment using the equivalent length method. Friction loss in fittings valves as an aid, liquid sizing constants cv values are shown for valves. Copper tubes pressure loss in fittings and valves expressed. Demonstrate how the flow coefficient c v is used to evaluate energy losses in some types of valves.
Because obtaining complete test data on the pressure drop of every available size and type of valve and pipe fitting is impossible, a practical. What ppi have called the equivalent length, using the symbol l eff, is a dimensional value and is the length of pipe that would be equivalent in pressure drop to the fitting. Table 3 friction losses through pipe fittings in terms. Represenrarrve eeutvalent length rn prpe diameters idoe various valves and fittings cnnnn co.
This notion is actually quite convenient to simplify the calculation of. However, common and lazy practice is to call the dimensionless ratio l eff d the equivalent length, even though it is actually a ratio and not a length at all. Nfpa valves and fittings tables engineered software knowledge. Valve and fitting losses valves and fittings cause pressure losses greater than those caused by the pipe alone. Pipe fittings for high pressure application are available. For calculating pressure drop across a pipe route, we need to calculate the total. Sample problem equivalent length calculation for piping. When calculating the pressure drop in a pipe, the pressure drop due to singularities, typically valves and fittings, can be calculated thanks to a pressure drop coefficient. Tube in the soft temper can be joined by the same techniques and is also commonly joined by the use of flaretype and compression fittings. Fitting equivalent lengths pressure losses in fittings are due to the turbulence created as water flows through the fitting. Equivalent length in feet of staight pipe for different fittings. Sep 04, 2008 i am working through a problem where i need to find the equivalent length of concrete pipe. Equivalent length of valves and fittings calculation for pipes with a nominal diameter from 12 to 24 inches there is certain amount of pressure loss in straight pipe and in addition valves and fittings in a section of pipe will add to the overall pressure loss that occurs in a section of pipe.
You enter the actual pipes length and diameter and the type and number of fittings and valves. Pdf finding equivalent pipe lengths of valves, section. Pressure loss in piping systems by using the equivalent pipe length method. One formulation expresses losses as 7 where k geometry and sizedependent loss coefficient tables 1, 2, and 3. The easiest way to apply the concept of equivalent length of. Using equivalent lengths of valves and fittings nov 08 2010 01. Im currently doing a project where i need to find cv values and equivalent length values for a set of valves. Resistance and fittings equivalent length in hot water systems equivalent length of fittings like bends, returns, tees and valves in hot water heating systems equivalent length in feet and meter. Crude oil is flowing through a 20 mile long, 12 in.
Fitting 900 elbow 450 elbow gate valve tee flow run tee flow branch malefemale adapter 12 1. The concept of the resistance coefficient k for valves and ffitings was in fact introduced through this paper. A previous article published by katmar software discussed the available methods including the equivalent length method for calculating the pressure drops in pipe fittings and valves. Pvc friction loss in fittings and equivalent length minor loss in pvc and cpvc fittings as equivalent length of straight pipe. One benefit to using valves and fittings, instead of the equivalent length, is that the length listed for a pipeline in the printed reports will be the actual length. Another advantage in using the loss coefficients in pipe flo is that when you view the pipeline in the graph window the head loss due to the valves fittings the minor loss is. If the overall pressure drop is equivalent to a pipe length of 16 diameters, and the pressure drop due to the actual flow path length which is affected by the roughness is equivalent to only 2. This tutorial uses sample calculations to demonstrate how to calculate equivalent length for piping fittings, joints and valves. The pressure loss in fittings is determined using the concept of equivalent length. Define and use the equivalent length technique for computing energy losses in valves, fittings, and pipe bends.
Add equivalent length of all valves, fittings and straight pipes. Ive figured out the cv values but am having trouble finding the equivalent length. A 6in schedule 40 commercial steel pipe of total length ft is equipped with the following pipe fittings. Equivalent length method calculating minor pressure loss. Equivalent length of valves and fittings equivalent length. Home technical information computation data equivalent length in feet of staight pipe for different fittings. View equivalent length of valves and fittings from stem 45 at technological institute of the philippines. Table 3 friction losses through pipe fittings in terms of. The equivalent length of common fittings found in piping is given for. Fill the number of valves, fittings in the piping system. Describe the energy losses that occur in a typical fluid power system. Equivalent length calculations for pipe fittings and. When the loss coefficient or k value method is used, the k value is multiplied by the velocity head to give the valve fitting head.
So, apart from the total length of all horizontal and vertical straight pipe runs, we need an associated length of straight pipes of the same diameter, which will incur the same pressure loss as the valves or fittings. Engineering toolbox resources, tools and basic information for engineering and design of technical applications. Pipe fitting, oint an ave 41 a plumber must also have knowledge of the various pipe fittings like elbow, union, gasket, etc. Values for welded fittings are for conditions where bore is not obstructed by weld spatter or backing rings. Equivalent length of generic fittings in feet screwed fittings flanged fittings hazen williams constants, c clean, new pipe 140 150 140 140 pipe material cast iron and wrought iron copper, glass or brass cement lined steel or iron plastic pvc or abs steel, welded and seamless or interior riveted typical range 80 150 120 150 120 150 80. Several methods to calculate the pressure drop expected in a pneumatic conveying pipe and design it is using the notion of equivalent pipe length. In simple terms, the theory of the equivalent length of fittings provides that for each fitting there will be an equivalent length of dummy pipe that generates a friction head loss equal to the localized head loss generated by this fitting, so that, when using a calculation equation for friction losses which are generally dependent equations of the pipe length analyzed, a length. The equivalent length of pipe to be used to estimate the friction loss due to fittings may be obtained by eq. Please set your resolution to this if it is not set so.
Ductile iron pipe fittings equivalent length sowhatso. Equivalent length of fittings like bends, returns, tees and valves in hot water heating systems equivalent length in feet and meter. Equivalent length of pipe calculator equivalent length is the length of pipe with diameter and friction factor having the same energy loss as a fitting solve for. Pipe fittings 4 how to order unilok pipe fittings are ordered by part number as shown as below. D is pipe bore diameter in ft and k is obtained from table 22. This application is a calculator for calculating equivalent length of fittings and valves. Equivalent length, l d eq of valves and pipe fittings. Where would i find a quick list of equivalent lengths for generic fittings for materials other than steel and cast iron. Elbows, sweeps and swooptms gary klein gary klein and associates, inc. The pressure drop through a fitting like a bend, tee or a valve is only slightly influenced by the surface roughness of the fitting and most of the pressure drop is due to the geometry of the fitting. If the valve is connected to 2 sch 40 steel pipe with an inside diameter of 0.
Equivalent length of pipe fittings for plastic and steel pipe. The standard pressure ratings for each thread sizes are based on asme b31. To convert a pressure drop in a fitting to an equivalent length of pipe i said you. The equivalent length method the l e d method allows the user to describe the pressure loss through an elbow or a fitting as a length of straight pipe this method is based on the observation that the major losses are also proportional to. The minor loss in a system component can be converted to the equivalent length of a pipe or tube that would give the same major head loss. Standard elbow medium radius elbow long radius elbow 45 elbow tee return bend gate valve open globe valve open angle valve open length of straight pipe giving equivalent resistance flow. Resistance and fittings equivalent length in hot water systems equivalent length of fittings like bends, returns, tees and valves in hot water heating systems equivalent length in feet and meter water flow in copper tubes pressure loss due to fricton water flow and pressure loss psift due to friction in copper tubes astm b88 types k. Topics pressure drop in pipe and fittings nesea conference, mar 79, boston, ma ashrae, june 2328, long beach, ca 90. Equivalent lengths of pipe fittings and valves katmar software. The easiest way to apply the concept of equivalent length.
Equivalent length for hdpe fittings pipelines, piping. Valves and fittings pressure drop equivalent length. The present article gives equivalent length values for a wide variety of pipe fittings and valves that can be used as described in that article. However, another method consists in considering that the fitting is equivalent in terms of pressure drop, to a certain longer of straight pipe. Equivalent length of fittings and valves the application is best viewed using a resolution of 1024x768 pixels.
A 6in schedule 40 commercial steel pipe of total length ft is equipped with the. Anvil pipe fitters handbook 5 gruvlok installation pipe and flange data weld fitting and steel flange data table of contents gruvlok tech. Below is the steps to calculate a piping system equivalent length. Instruction at left side is a pipe equivalent calculator developed by oilgas engineers. Tables 14 show the equivalent lengths as specified by the nfpa 15 standard for a variety of valves and fittings for schedule 40 steel pipe with a c value of 120. Ductile iron pipe fittings equivalent length pipelines. From the current ashrae fundamentals pipe sizing chapter hegberg 1995 and rahmeyer 1999a, 1999b discuss the origins of some of.
The effect of pressure drop through valves and fittings is negligible when the ratio of pipeline length to pipe, diameter is equal to or greater than to 1, as is usually the case for long water and oil pipelines with the usual number of fittings and valves. Definition what does equivalent length of pipe mean. Pressure drop in pipe and fittings many materials and types of fittings calculations vs. Engineering data bulletin 90 engineering data crane pumps. Pressure drop in pipe fittings and valves equivalent length. Then, depending on the c value and the pipe inside diameter in relation to steel schedule 40 inside diameter, there are factors to multiply the equivalent length.
This technique, known as the equivalent length method. Define and use the equivalentlength technique for computing energy losses in valves, fittings, and pipe bends. The nfpa 15 standard has equivalent lengths for valves. It has been found experimentally that for a given type of fitting e. To determine the pressure drop for a given gpm the following formula may be used. Equivalent length calculations for pipe fittings and valves.
The cerm only gives equivalent length values for steel and cast iron. Oct 05, 2012 fittings such as elbows, tees and valves represent a significant component of the pressure loss in most pipe systems. Approximate friction loss for pvc and cpvc pipe fittings in equivalent length in feet for water. Then, depending on the c value and the pipe inside diameter in relation to steel schedule 40 inside diameter, there are factors to multiply the equivalent length by. The strength of the equivalent length method is that it is very simple to calculate. The table below shows the straight pipe equivalent length that produces the same friction loss caused by piping elements.
Friction loss in fittings watts water technologies. Nfpa valves and fittings tables engineered software. Hence, the pressure losses in fittings are constant for a given flow q, regardless of the type of pipe used to construct the system. Equivalent length of a pipe with fittings and valves.
Length of straight pipe giving equivalent resistance flow. Friction losses in pipe fittings resistance coefficient k. This demonstration estimates the equivalent length of a pipe that determines the frictional pressure drop in fluid flow by converting the number of fittings and valves into an analogous length and adding it to the actual length. Select the appropriate k value for such and select d and f for schedule 40 pipe from the table below where k is the pipe diameter in feet.
Pressure loss from fittings equivalent length method neutrium. Determine l friction loss in pipe fittings in terms of equivalent length in feet of straight pipe. Ductile iron pipe fittings equivalent length katmar chemical 12 aug 09 04. Schedule 40 head loss per 100 values are usually used for other wall thicknesses and standard iron pipe size o. Equivalent lengths engineered software knowledge base. Long radius and reducing elbows, reducing ontherun tees, side outlet fittings, eccentric reducers and. Problem statement calculate the equivalent length and combined kfactor for following set of fittings,90 0 elbows 5 nos. Equivalent length of a pipe fitting is defined as the frictional losses caused due to the pipe fitting that is equivalent to frictional losses caused by a straight pipe of length ld e, where.
Equivalent length pipe fittings free download as pdf file. Finding equivalent pipe lengths of valves, section changes, and miter bends. Refer to table 5 for estimations of equivalent lengths of valves and fittings. A frequently used rule of thumb assumes that the design length of pipe is 50 to 100% longer than actual to account for fitting losses.