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ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014Determination of Maximum Support Span,Location and Necessity of Pipe Support UsingCAESAR IITambe Prachi N 1, Dr. Dhande K. K. 2, Jamadar N. I.3P.G. Student, Department of Mechanical Engineering, DYPIET, Pimpri, Pune, India1Professor, Department of Mechanical Engineering, DYPIET, Pimpri, Pune, India2Professor, Department of Mechanical Engineering, DYPIET, Pimpri, Pune, India3ABSTRACT—Piping system is always need to be supported to prevent failure due to its self weight, operatingpressure and temperature conditions etc. To decide the location and number of supports is very important as the wronglocation of support may lead to failure of a whole system. This study is focused on the criterion of selection of pipingsupport. The maximum span and deflection calculation is carried out and the piping system with intermediate supportand without intermediate support is analysed in CAESAR II software. The two systems are compared and optimizedthe number of supports by considering the effect of support on nozzle loads and stresses .KEYWORDS— Support Location, Piping Support, Maximum support span, maximum deflectionI. INTRODUCTIONPipe supporting plays a vital role in designing a process plant. A pipe support is designed elements that transfer theload from the pipe to the supporting structures. The load includes the weight of pipe, the content the pipe carries, all thepipe fittings attached to pipe & the pipe covering such as insulation. The four main functions of a pipe support are toanchor, guide, absorb shock and support a specified load. Pipe supports used in high or low temperature applicationsmay contain insulation materials. The overall design configuration of a pipe support assembly is dependent on theloading and operating conditions.The basic types of supports can be as follows:Sustained Loads: These are typically steady or sustained types of loads such as gravitational forces acting on the pipesuch as weight of pipe and fluid, forces due to relief or blow down, pressure waves generated due to water/steamhammer effects.Operating Loads: These are typically due to operating internal and external pressure.Expansion Loads: These are due to temperature differences in maximum operating and normal ambient temperature.II. RELATED WORKSupport span charts for various pipe sizes (DN 15-DN600) are provided by codes like ASME B 31.3 and ASME B 31.1.These spans are used as guidelines for pipe supporting. But the maximum span calculated using Bending Stress Theoryis more with stresses in the allowable limit than the chart span value. This saves the number of supports and hence thecost [3]. Optimal pipe support span for geothermal pipe lines is calculated using code ASME B 31.1[4]Copyright to IJIRSETwww.ijirset.com14860

ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014III. PIPE SUPPORT LOCATIONThe locations of piping supports are dependent upon four factors: pipe size, piping configuration, locations of valvesand fittings, and the structure available for support. Individual piping materials have independent considerations forspan and placement of supports.Pipe size relates to the maximum allowable span between pipe supports. Span is a function of the weight that thesupports must carry. As pipe size increases, the weight of the pipe also increases. The amount of fluid which the pipecan carry increases as well, thereby increasing the weight per unit length of pipe. The configuration of the pipingsystem affects the location of pipe supports while valves require independent support. These items contributeconcentrated loads to the piping system. Independent supports are provided at each side of the concentrated load.Location, as well as selection, of pipe supports is dependent upon the available structure to which the support may beattached.IV. PIPING SYSTEM SUPPORT DESIGNPipe Data considered for design is:Pipe Size: DN 1000Pipe Thickness: 6 mmPipe Material: A358 TP 304Max. Operating temperature: 1000cMax. Operating Pressure: 0.28 barFluid density: 0.42 kg/m3Ambient Temperature: 250cInsulation Thickness: 70 mmInsulation density: 120kg/m3Flange Rating: #150Flange Width: 164 mmFlange Weight: 4546 NOnce the piping and fittings size, rating , thickness, material, operating conditions, Fluid density, insulation material isknown, the support span calculation can be done using the usual beam formulas, which depend on the method ofsupport and type of loading. [3]Maximum Bending Stress,Sb (N/m2) (0.0624wL2 0.1248wcL)DIMaximum deflection,y (meter) 5wL4 8wcL3384EIWhere,w uniformly distributed weight of pipeline in N/mwc concentrated weight on pipeline in NL Span length in mD Outside diameter of pipe in md Inside diameter of pipe in mE Modulus of elasticity of pipe in N/m2I Moment of Inertia of pipe in m4(1)(2)Maximum bending stress of pipe can be taken as 30% of allowable stress. [2]Sb 41.36 MPa (30% of 137.87 MPa)Copyright to IJIRSETwww.ijirset.com14861

ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014Weight of stainless steel pipe 63094.3 N/mWeight of Fluid in pipe 3.34 N/mWeight of Insulation 148.33 N/mTotal Weight (w) 63377.6 N/mConcentrated Load due to flange (wc) 4546 NMoment of Inertia (I) 0.05146 m4Substituting above values in the maximum bending Stress equation:Maximum span between supports is calculated as 23.13 m and maximum deflection calculated is 23.6 mm which is lessthan L/600, hence the calculated span is also safe in deflection.V.PIPING SYSTEM WITH INTERMEDIATE SUPPORTConsider a piping system with two anchors at end and intermediate support.Fig: 1- Isometric view of piping System with intermediate SupportThe calculated values of maximum span and deflection are for straight run pipe. As the piping system consideredconsists of number of bends, the above criterion of maximum span shall not be applicable. As a general rule,intermediate support is considered immediately after bend after a large vertical distance [2]The piping system is modelled in CAESAR II software and following are the isometric drawing, displacement atvarious points, stresses and nozzle loads observed.Fig: 2- 3D modeled piping System with intermediate SupportCopyright to IJIRSETwww.ijirset.com14862

ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014Table 1- Nodal Displacement of piping system with intermediate support - CAESAR outputNODE1020282930383940484950555859607080DX 0.0000-0.0000DY 022-0.0000DZ 0680.00000.0000RX .00530.00000.0000RY .00000.00000.0000RZ 0.0000-0.0000Table 2- Nozzle Load on Tanks for the piping system with intermediate support- CAESAR outputNODE10Load CaseFY lb.FZ lb.MX ft.lb.MY ft.lb.MZ ft.lb.1(OPE)2(SUS)3(EXP)FX lb.Rigid PE)2(SUS)3(EXP)MAX801(OPE)2(SUS)3(EXP)MAXCopyright to IJIRSETRigid Y00-00/L2Rigid ANC-0-0-0-0/L1www.ijirset.com14863

ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014VI. PIPING SYSTEM WITHOUT INTERMEDIATE SUPPORTConsider a piping system with two anchors at end and without intermediate support. Vertical distance is balanced asshown. N1 and N3 are the anchor points i.e the nozzles of equipment.FIG: 3- ISOMETRIC VIEW OF PIPING SYSTEM WITHOUT INTERMEDIATE SUPPORTConsider a piping system with two anchors at end and the vertical distance is balanced as shown. The system ismodeled in 3D software CAESAR II without intermediate support. The vertical distance is varied in order to balancethe stresses on the anchor points (Nozzles of the equipment.). Following are the isometric drawing, displacement atvarious points, stresses and nozzle loads observed.Fig: 4- 3D modeled piping System without intermediate SupportCopyright to IJIRSETwww.ijirset.com14864

ISSN: 2319-8753International Journal of Innovative Research in Science,Engineering and Technology(An ISO 3297: 2007 Certified Organization)Vol. 3, Issue 7, July 2014Table 3- Nodal Displacement of piping system without intermediate support - CAESAR outputNODE10202829303839404849505859607080DX 0-0.0000DY -0.0000DZ 000.0000RX 000-0.0000RY 00.00000.0000RZ 000Table 4- Nozzle Load on Tanks for the piping system without intermediate support- CAESAR outputNODE10Load pyright to IJIRSETFX lb.Rigid ANC0000/L1Rigid ANC-0-0-0FY lb.FZ lb.MX ft.lb.MY ft.lb.MZ 87.811266.9/L20.0/L1-0.0/L1www.ijirset.com14865