A.V.C COLLEGE OF ENGINEERINGMANNAMPANDAL

DEPARTMENT OF

MECHANICAL ENGINEERING

14th Batch

TEAM MEMBERS

•X.ALLAN ROY•P.ARUNKUMAR•R.ARUNKUMAR•D.SANTHOSH

Under the Guidance of

External Guide Internal Guide

Mr. M.Rajakumar, Mr.A.Hajamaideen.M.E.,

Sr. Manager, Sr. Lecturer, BHEL, Trichy. A.V.C College of Engineering, Mayiladuthurai.

FLOW OF PRESENTATION

Project title Objective Methodology Diagrams Conclusion Future Scopes

PROJECT TITLE

3D MODELING & FINITE ELEMENT ANALYSIS OF

14” & 10” CLASS 3500 GATE VALVES.

CARRIED OUT AT :

BHARATH HEAVY ELECTRICALS LTD.,(BHEL) TRICHIRAPALLI

OBJECTIVE

The main objective of the project is,

To design the 3D modeling of 14” Class

3500 Gate Valve and 10” Class 3500 Gate Valve

and analyze the internal stresses formed in the

inner parts of gate valves.

• In this project, the stress pattern and deformation of existing 14” class 3500 valve (Proven Design) is analyzed and the same criteria is applied to 10” class 3500 gate valve (Developed).

• The 14” gate valve is presently running in 55-mw captive power plant in Chhattisgarh.

• And also the Power Plants in other states of India like Orissa, Andhra Pradesh, Lucknow are using this 14” gate Valve in Steam pipe line of boiler.

• The 10” gate valve to be designed by us should be used in the place of 14” gate valve with same stress and deformation.

•The developed 10” valve is also going to be used in “Krishna Patla” Power plant in Karnataka and also to the other power plants in India.

•Assembly models have been generated with UNIGRAPHICS 4.0 and analyzed in ANSYS 11.0.

• The deformation and stress concentration at various zones of the proven valve should be in the allowable limit for the safe design.

Company ProfileBharat Heavy Electricals Limited (BHEL), established in 1953, is one of leading power generation equipment manufacturers in the world. BHEL has 14 manufacturing units, 13 Regional Operation Divisions and more than hundred "service-at-sites" facilities spread all over India.

BHEL Tiruchirapalli has equipped all its units with sophisticated world class machinery, which form the heart of the manufacturing system.

BHEL is the first state-owned company to acquire ISO 9000 certification during 1993 for all its operations. This is being successfully maintained through surveillance and recertification audits.

BHEL Trichy has been accredited to ISO 14001 Standard - signifying its clear commitment to clean and pollution free environment.

METHODOLOGY

For performing the stress analysis, solid model of the gate valve parts are modeled in the UNIGRAPHICS 4.0 software as per the given 2D diagrams.

The created 2D model is to be converted to 3D solid model by using various tools available in the UNIGRAPHICS 4.0 package for the modeling of the gate valve parts.

Main parts of the gate valves are,

Body

Bonnet

Wedge

Yoke

Stem

14” Gate Valve

Hand Wheel

Stem

Yoke

Body

Wedge

Model of a 14” Gate

Valve

Modeling of the components of Gate Valves

Modeling of Body

14” Gate Valve

10” Gate Valve

Modeling of Bonnet

14” Gate Valve 10” Gate Valve

Modeling of wedge

14” Gate Valve 10” Gate Valve

Modeling of Stem

14” Gate Valve 10” Gate Valve

Modeling of Yoke

14” Gate Valve 10” Gate Valve

Modeling of other parts

RETAINING RING BUSHING GLAND FLANGE

WASHER

SUPPORTING RING GASKET

ASSEMBLED MODEL

14” Gate Valve 10” Gate Valve

The stress analysis is to be carried out in ANSYS for the below parts

• Bonnet

• Body

• Wedge

The model has so many curvatures and complicated profiles, then mapped meshing in ANSYS is not possible for the model. Then the only option available meshing the model in Hyper mesh software10.0.

MESHED GATE VALVE BODY

14” Gate Valve 10” Gate Valve

BOUNDARY CONDITIONS

PRESSURE LOADING

For Both valves,

Internal Pressure = 615 Kg/cm2

Room Temperature = 380C

•The body is either bolted or welded with the piping system.

•Hence it is not allowed to move either side.

•So Flange end portion is fixed with all degrees of freedom.

MATERIAL PROPERTIES

The material properties are considered homogenous through out the body. So, the isotropic material properties are considered for the gate valve body analysis,

Material = Carbon Steel (WCB)Young’s modulus ‘E’ = 2.1E5 N/mm2

Poisson’s Ration = 0.3Yield Strength = 248MPaDensity = 7850Kg/m3

14” Gate Valve 10” Gate Valve

Stress Analysis results for Gate Valve body

Displacement Analysis results for Gate Valve body

14” Gate Valve 10” Gate Valve

S.No

BodyMaximum

StressMPa

Maximum Deformation

mm

1 14”3500 137.78 0.24362

2 10”3500 107.56 0.0948

RESULT OF BODY ANALYSIS

MESHED GATE VALVE WEDGE

14” Gate Valve 10” Gate Valve

The one side of the wedge meets the fluid pressure, the other side which is just in contact with the valve body, is not allowed to move due to this fluid pressure, so we are arresting the all DOF in the surface, which is just in contact with the valve body.

BOUNDARY CONDITIONS

PRESSURE LOADING

For Both valves,

Internal Pressure = 615 Kg/cm2

Room Temperature = 380C

MATERIAL PROPERTIES

•The material properties are considered homogenous through out the body.

•So, the isotropic material properties are considered for the gate valve wedge analysis,

Material = Carbon Steel (WCB)Young’s modulus ‘E’ = 2.1E5 N/mm2

Poisson’s Ration = 0.3Yield Strength = 248 MPaDensity = 7850Kg/m3

Stress Analysis results for Gate Valve Wedge

14” Gate Valve 10” Gate Valve

Displacement Analysis results for Gate Valve Wedge

14” Gate Valve 10” Gate Valve

The 10”3500 and 14”3500 wedge is analyzed by applying above condition, their von misses stress plots and plots, and maximum deformation plots are shown in figure. Neglecting the sharp corners, the valves of maximum stress and deformation are within the allowable limits.

S.No Body

Maximum

StressMPa

Maximum Deformation

mm

1 14”3500 39.318. 0.029282

2 10”3500 39.494 0.024321

RESULT OF WEDGE ANALYSIS

MESHED GATE VALVE BONNET

14” Gate Valve 10” Gate Valve

The one side of the bonnet meets the fluid pressure, the other side which is just in contact with the bonnet flange, is not allowed to move due to this fluid pressure, so we are arresting the all DOF in the surface, which is just in contact with the bonnet flange.

BOUNDARY CONDITIONS

PRESSURE LOADING

For Both valves,Internal Pressure = 615 Kg/cm2

Room Temperature = 380C

MATERIAL PROPERTIES

The material properties are considered homogenous through out the body. So, the isotropic material properties are considered for the gate valve wedge analysis,

Material = Carbon Steel (WCC)

Young’s modulus ‘E’ = 2.1E5 N/mm2

Poisson’s Ration = 0.3Yield Strength = 275 MpaDensity = 7850Kg/m3

Stress Analysis results for Gate Valve Bonnet

14” Gate Valve 10” Gate Valve

Displacement Analysis results for

Gate Valve Bonnet

14” Gate Valve 10” Gate Valve

RESULT OF WEDGE ANALYSIS

The 10”3500 and 14”3500 Bonnet is analyzed by applying above condition, their von misses stress plots and plots, and maximum deformation plots are shown in figure. Neglecting the sharp corners, the valves of maximum stress and deformation are within the allowable limits.

S.No WedgeMaximum

StressMPa

Maximum Deformation

Mm

1 14”3500 83.874 0.010300

2 10”3500 95.602 0.06344

Conclusion By comparing the deformation and stress concentration at various zones of the proven valve and the developed valve,

It clearly shows that the stress and deformation occurs in the developed valve is slightly over than the proven valve.

At the same time it comes below the allowable limits.

This is due to the change of the dimensions and thickness of the developed valve.

The 14” Gate Valve is successfully running in power plants all over India.

By using the same material, 10”valve is designed.

The Stresses and deformation ranges are also lie below the allowable limits.

So we strongly conclude that the developed 10” Gate Valve is also a Perfect Valve that is suitable for power plant working conditions.

Future Scopes

By modifying the dimensions of the developed 10”valve ,further we can minimize the stresses and deformation