Volume 119 No. 12 2018, 15791-15800activity. CAESAR II is unique in incorporating calculation methods and analysis option. It provides static and dynamic analysis of piping systems

Stress Analysis of Power Piping from Auxiliary Steam Piping to Air heater Soot Blowing

S.Aathresh T.Madan kumar V.Velmurugan Department of Mechanical, Saveetha school of Engineering, Thandalam, Chennai.

[email protected] ABSTRACT

The most appropriate method to check whether the process is running in safe and economic

condition is by product analysis. This method contributes the best possible conditions showing that the work carried are up to the permissible limits issued by the department of safety conditions. Hence a process plant is regulated safely and effectively only through a safe piping system. The piping parameters play a significant role in the effectiveness and efficiency of a process plant.

Design of piping parameters include pipe fitting, thickness, equipment layout, size calculations, support type, pipe routing, location and mainly pipe line traversing and stress analysis Pipes are installed in an industry to carry out the necessary fluids from one place to another. The designing

and construction of piping systems in any plant are expensive and time consuming and complex effort. Each piping code specifically denotes the work and applications of the piping system used in a plant. The basic piping code used in this paper is ASME B 31.1. The objective of this paper is to

show that the piping design of Auxiliary steam piping to Air heater soot blowing are according to piping code and in safe conditions so that the design is optimum in condition. However the piping design is done in CAESAR II software and static analysis is carried out in order to find out code

compliance stresses, elemental forces, displacement at all nodes, sorted code stress, moments in coordinates in the piping layout. By comparing the SIF results against the software depicted results are according to the safe running conditions. Keywords: ASME B 31.3, Stress intensification factor (SIF), CAESAR II, Code compliance, Piping code. 1.INTRODUCTION

International Journal of Pure and Applied MathematicsVolume 119 No. 12 2018, 15791-15800ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu

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Pipe design mainly depends upon stress analysis. The main objective of pipe stress engineer

is to verify the routers, hangers and supports are placed correctly in the process plant and the allowed pipe stress is not to exceed by various loads acting along the piping system specified by

ASME B31 conditions and standards. Mechanical behavior of pipes is strictly evaluated under various loading conditions. CAESAR II: Computer Aided Engineering Stress Analysis and Routing is a complete software related to pipe stress analysis developed by INTEGRAPH corporation used

to calculate and measure quick analysis of piping system that is bullied to weight, pressure, thermal, seismic and static and dynamic loading resulting from the effects of gravity, temperature changes, internal and external pressures, changes in fluid conveyance flow rate and seismic

activity. CAESAR II is unique in incorporating calculation methods and analysis option. It provides static and dynamic analysis of piping systems. This paper deals with the reference of stress analysis in a process piping determined by the software used upon their respective

application. Many pipe stress analyzing programmes are available in the market and their usage depends upon the field they are utilized. The most widely used software in the field of pipe stress is PDMS, CAEPIPE, CAESAR II. A pipe is modeled as several elements connected to a common

nodal point. Then the appropriate loads are applied and using boundary conditions the problem is solved using finite modern element approach.

C. Basavaraju[1] has carried out an immense work on Stress analysis of piping systems

highlighting the scope of piping systems, supports, materials, fittings, insulation, operating medium in a pipe line & Finite analysis of main stream in pipe line. Hence his parametric study is helpful for calculating the involved stresses and problems in a piping system. G.M. Pradeep

[2] objectified his paper on Analysis of thermal flexibility in an expansion loop using CAESAR software. This work concluded that installation of piping loops is the best possible way to increase

the piping system flexibility. Shweta Bisht & Farheen Jahan [3] has explained the need of Design of piping system in the world of fluid conveyance and concluded that stress analysis is a critical component of piping design through which important parameters such as piping safety, safety of

related components and connected equipment and piping deflection can be checked and rectified timely. M.Jamuna Rani& K.Ramanathan[4] has done the analytical study of piping system using CAESER software and concluded that displacement in the piping system of expansion joint is

comparatively lower than piping system with hangers.Bahaa Shehadeh, Shivakumar Ranganathan & Farid H Abed[5] et.al carried a work on expansion loop in a piping system to determine the loads and stresses are acted in a piping system. Payal Sharma Ȧ , Mohit Tiwari Ȧ & Kamal Sharma A[6]

et.al carried a work on Design and Analysis of a Process Plant Piping System and suggested different ways of stress calculations for a stress load and flexibility of a expansion loop and analysis of it using CAESER II. D. M. Awze, A. K. Mahalle [7] et.al proposed a method titled comparative analysis analysis of different piping configurations for piping flexibility[8] by comparision analysis using FEA technique.

2. EXPERIMENTAL PLAN

In the course of process pipeline it encounters many system parameters including stress, load variation, flexibility, structure, buckling and many more. An engineer has to encounter these conflicts in order to maintain an effective environment in the industry. The main cause for

economical deficiency in a process plant is due to the applied stresses on the piping routers. It is

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difficult to any maintenance engineer to cross check all these variations, hence many piping software were developed. These suggest the best piping parameters for the applied load on a piping

system. Economical analysis of a chemical plant in recent studies shows the major pipe loss factors are due to even stress and load acting on them. Therefore attention is focused towards the attainment of flexibility and optimization of piping layouts in their applications of process piping.

Standardization of piping layout can reduce cost, inconvenience and unrelated disturbances in the routers. Hence optimization techniques like installation of expansion loops, hanger supports, anchors are encouraged. These evaluations include pipe moments, anchorage

force, soil friction, lateral soil and environment pipe interaction. In these existing methodologies proposing the concept of pipe stress analysis leads to a new way invention regarding better optimization techniques in CAESAR II software. This commercial data software is used in process industries to gain significant savings in plant ergonomics. Therefore an existing profound concept

of analyzing auxiliary steam in a piping system is emphasized. Auxiliary steam is used in power plant section for various process applications like sooth blowing and in mill pulverizing. A pipe suffers significant amount of stress and sometimes leads to failure of plant. Hence CAESAR II

software is used to calculate stress analysis acting on the pipe line carrying auxiliary steam. This software obtained result concludes the optimization techniques to be followed in the optimization of layout for this process. A layout is designed in the software and analysis is done for the process

piping system. This study gives the safe routing parameters for designing the piping layout from Auxiliary Steam Piping to Air heater Soot Blowing. 2.1 Input data for stress analysis

The following figure 2.1 illustrates the piping input parameters for stress analysis done in CAESER ii software.

Figure 2.1 Input data parameters


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2.2 Input Data

The following Table.1illustrates about the input parameters of piping layout done in CAESER II Software.

Table.1Input parameters of piping layout

Diameter 168mm

Thickness 7mm

Pipe material SA 106 grade B

Density of pipe material 0.0789 kg/cu m.

Temperature 210 deg C

Pressure 20 kg/cm2

Type of Fluid Saturated Fluid

Insulation Thickness 95mm

Fluid density 0.001 kg/cm3

2.3 Design of piping layout A piping layout is designed using CAESAR II software in the boiler section for application of

soot blowing.

The figure 2.3.1 illustrates the isometric view of piping layout given by NTPC( National Thermal Power Corporation).

Figure 2.3.1 Isometric view of piping layout

The figure 2.3.2 illustrates the isometric piping layout and it is done in CASER II Software.


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Figure 2.3.2 Model of piping layout

A pipe engineer has to cross check all the included parameters in designing the piping layout for the power plant. Certain optimization techniques are used in designing the layout by considering the plant economics and safety. These steps may increase the plant life and efficiency of the boiler in the power plant.

Figure 2.3.4 illustrates that the model is done in AUTOCAD Software and the yellow line in figure shows the required piping layout.

Figure 2.3.4 Yellow line showing the pipe layout

3. RESULTS AND DISCUSSION

3.1 Stress Analysis as Per Code ASME B31.3

Code ASME Stands For American Standard For Mechanical Engineering And B31.3 Code Stands For Analysis.Results are obtained using CASER Software as shown in figure 3.1.1.From the values,It is concluded that the stress acting on piping system are in safe condition.


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Figure 3.1.1 stress acting at different loading conditions

3.2 Global distribution of forces and moments in different load conditions

At Node 10

From the Table.2 various loads are acting at node 10 and the values obtained in the table.2 are in permissible limit.

Table.2 Restrain summary at node 10

RESTRAINT SUMMARY REPORT : Loads On Restraints

Various Load Cases LOAD CASE DEFINITION KEY


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CASE(OPE) W+T1+P1+H

CASE(SUS) W+P1+H

CASE(EXP) L7=L4-L6

NODE LOAD FX N. FY N. FZ N. MX MY MZ

CASE N.m. N.m N.m

10 RIGID

ANC

4(OPE) -236 -1710 1814 4423 842 1527

6(SUS) -0 -869 0 11 2 -43

7(EXP) -236 -841 1814 4412 840 1570

MAX -236/L -1710/L 1814/L 4423/L 842/L 1570/L

4 4 4 4 4 7

From the graph various load are acting at node 10 and the Figure 3.2.1.1.illustrates about the Distribution of forces and moments at node10 and the values obtained are in permissible limit.

3.2.1GraphicalAnalysis of Forces &Displacements in all Load cases

At Node 10

DISTRIBUTION OF FORCES AND MOMENTS

DISTRIBUTIO N O F FO RCES AND MOMENTS

5000

Mo

men

ts

4000

3000

an

d

2000 4(OPE)

Fo

rces

1000 6(SUS)

Rest

ra

in

0 7(EXP)

-1000 1 2 3 4 5 6 7

MAX

-2000

-3000 AT NO DE 10:: RIGID ANCHOR SUPPORT

Figure3.2.1.1.Restrain analaysis at Node 10

The above graph states that stress limit in the designed pipe line is upto the permissible limit .


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3.3 Global distribution of forces and moments in different load conditions :

At Node 410

From the Table.3 various loads are acting at node 410 and the values obtained in the table.3 are in permissible limit.

Table.3 Restrain summary at node 410

RESTRAINT SUMMARY REPORT : Loads On Restraints

Various Load Cases

LOAD CASE DEFINITION KEY

CASE(OPE) W+T1+P1+H

CASE(SUS) W+P1+H

CASE(EXP) L7=L4-L6

NODE LOAD FX N. FY N. FZ N. MX MY MZ

CASE N.m. N.m N.m

410 RIGID

ANC

4(OPE) -137 -1160 -71 -1 426 -315

6(SUS) -0 -1479 0 988 -2 -27

7(EXP) -137 319 -71 -989 429 -288

MAX -137/L -1479/L -71/L -989/L 429/L 315/L

4 4 4 4 4 7

From the graph various load are acting at node 410 and the Figure 3.3.1.1.illustrates about the Distribution of forces and moments at node 410 and the values obtained are in permissible limit

3.3Graphical Analysis of Forces &Displacements in all Load cases

At Node 410

Distribution of forces

and moments

AN

D

MO

MEN

TS

AIN

FO

RC

ES

5000 OPE

0 SUS

1 2 3 4 5 6 EXP

-5000

AT NODE 410:: RIGID ANCHOR MAXSUPPO

Figure3.3.1.Restrain analaysis at node 410


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The above results and graphs states that the stress limit in the designed pipe line is up to the permissible limit and the design can be considered for the installation of the pipe line design in the boiler section of power plant.

4. CONCLUSION

Analysis of piping layout is wide spread concept and it is gaining importance all around the corner. It is important for an engineer to calculate all the implied stress and load factors to ensure that the plant is working is working in safe operating conditions. These optimization techniques calls for pipe savings and leads to cost efficient process plant. In order to save material costs

various techniques are employed like installation for new equipments, analyzing the material, modeling new process plant layout etc. Results indicate that by following these standardized techniques increases plant life and also lead to positive quality management. This environment

provides the ability to iterate the layout easily and saves time by reducing the time of consta nt inspections.

In sustained condition, the displacement, stress and code compliance reports as per ASME

B31.3 were analyzed and its values were tabulated. In expansion condition, the displacement, stress and code compliance reports as per ASME B31.3 were analyzed and its values were tabulated. Since the sustained and expansion stress values are less than the allowable stress values as per ASME 31.1. The process pipe routing was accepted.

5. REFERENCES

[1] C Basavaraju,“Stress Analysis of Piping Systems”, 2004, Published by McGraw Hill, pp. B107-B120 [2] “G.M. Pradeed”, STRESS ANALYSIS OF PROCESS PIPING USING CAESAR II IJRME-

International journal of research in Mechanical Engineering,2016,volume: 03 ISSN: 2349-3860. [3] AN OVERVIEW ON PIPE DESIGN USING CAESAR II “Shwetha Bisht and Farheen jahan” International Journal on Emerging Technologies, ISSN: 2249-3255. [4] M. Jamuna Rani, K. Ramanathan,Design and Analysis of Piping System with Supports Using CAESAR-II, 2016,Vol:10, No:5 [5] OPTIMIZATION OF PIPING EXPANSION LOOPS “Bahaa Shehadeh,shivakumar Ranganathan & Farid H abed, 2016, Vol. 230(1) 56–64. [6]FLEXIBILITY AND STRESS ANALYSIS OF PIPING SYSTEM USING CAESAR II “Prachi N Tambe” International Journal of Engineering Research & Technology (IJERT) ISSN: 2278-0181. [7] ] D. M. Awze, A. K. Mahalle “Design of Steam Pipe Layout and HangerSupport in Thermal Power Station” International Journal of RecentTechnology and Engineering (IJRTE) , May

2013.ISSN: 2277-3878,Volume-2,Issue-2 [8] A.Ramya, 2L.Kalaiselvi A HIGH THROUGHPUT FPGA BASED ARCHITECTURE FOR REAL TIME EDGE AND CORNER DETECTION International Journal of Innovations in Scientific and Engineering Research (IJISER)


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Volume 119 No. 12 2018, 15791-15800activity. CAESAR II is unique in incorporating calculation methods and analysis option. It provides static and dynamic analysis of piping systems