Pwht - [part 1] How To Read A Pwht Chart - Mechanical Construction Industry 475j5p
This document was ed by and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this report form. Report 3b7i
Overview 3e4r5l
& View Pwht - [part 1] How To Read A Pwht Chart - Mechanical Construction Industry as PDF for free.
More details w3441
- Words: 770
- Pages: 7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
PWHT - [Part 1] HOW TO READ A PWHT CHART 5:11 PM
Due to the advancement of metallurgy a lot many di erent materials are now used in mechanical construction industry. In this a few are heat treated to improve mechanical properties. Heat treatment is done because of two reasons 1 ) Process requirement 2) Material Requirement Heat treatment can be done in many ways. Furnace heating, Oil red heating, Electric resistance heating etc. There are di erent type of heat treatments like normalizing, annealing etc. Here we are going to discuss about the graph which is generated in electric resistance heating for PWHT (Post Weld Heat Treatment). Reading a PWHT chart is what is going to be discussed here.... Below is the graph of a pwht process. Lets start reading it.....(Here i am discussing on the understanding that you are a little bit familiar with the process....)
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
1/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
In this chart, http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
2/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
X-axis represents temperature and Y-axis represents Time. In X-axis each line to line distance represents 10Deg C (See it is written as X 100°C, that means in X axis, 2 means
2 X 100°C= 200°C, 3 means 3 X 100°C= 300°C etc.) In Y-axis each line to line distance represents half an hour. That means the time between 2 and 3 represents one hour. These are the basics. How to read the graph?
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
3/7
11/16/2016
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
4/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
The graph contains several lines, AB, BC, CD, AE 1 ) AB is RATE OF HEATING curve 2) BC is SOAKING TEMPERATURE 3) CD is RATE OF COOLING curve 4) AE is ROOM TEMPERATURE curve When you check the WPS you can see the required values for each of these. 1) AB: Rate of heating: In WPS it is mentioned as a maximum value. In the graph the rate of heating is the slope of the curve AB. So the value of the slope should not be more than the value in WPS. How to calculate the slope: Slope = kl/lm Now in the graph given above, for AB line, kl=80DegC and lm=1/2 hr slope = 80 / (1/2) = 160DegC/hr ; So in this graph the rate of heating is 160DegC/hr. 2) BC: Soaking Temperature: In WPS it is mentioned as a single value with some plus/minus allowance along with time it is to be steady(mentioned as minimum) Here in this graph it is 720Deg (Reading in X-axis) and for approximate 2hr and 10minute(this is an approximationReading in Y-axis )
3) CD: Rate of cooling: In WPS it is mentioned as a maximum value. In the graph the rate of heating is the slope of the curve CD. So the value of the slope should not be more than the value in WPS.
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
5/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
How to calculate the slope: Slope = qr/pq Now in the graph given above, for CD line, qr=130DegC and pq=45 Min(this is taken as an approximation from the graph.) slope = 130 / 45 = 2.89DegC/Min ; So in this graph the rate of heating is 173DegC/hr.
4) AE: Room Temperature: This is the room temperature, here it is 40 deg C. Loading Temperature: Loading temperature is the temperature at which controlled heating (maintaining the rate of heating in the WPS) starts, up to which there is no need for controlled heating. Unloading Temperature: Unloading temperature is the temperature up to which controlled cooling (maintaining the rate of cooling in the WPS) occurs, below which there is no need for controlled cooling.Normally the power connection is disconnected below the temperature, keeping the insulation. After getting cooled to the atmospheric temperature the insulation is removed. NB: Please check the speed of the chart movement in the PWHT machine, Normally it is 25mm/hr. -----------------------------------------------------------------------------------------------------------PWHT [PART-2]: http://hareeshkv.blogspot.com/2015/06/pwht-part-2-thermocouples.html
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
6/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
Induction Heating Systems Encur, Inc. is a worldwide leader in induction heating systems. Go to encur.com
Local Furnace Experts ExpressCoils - Buy Small Coils Beryllium Copper, Brass & More Hempel Firmus Metals Ltd - Coil, Sheet, Precision Strip
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
7/7
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
PWHT - [Part 1] HOW TO READ A PWHT CHART 5:11 PM
Due to the advancement of metallurgy a lot many di erent materials are now used in mechanical construction industry. In this a few are heat treated to improve mechanical properties. Heat treatment is done because of two reasons 1 ) Process requirement 2) Material Requirement Heat treatment can be done in many ways. Furnace heating, Oil red heating, Electric resistance heating etc. There are di erent type of heat treatments like normalizing, annealing etc. Here we are going to discuss about the graph which is generated in electric resistance heating for PWHT (Post Weld Heat Treatment). Reading a PWHT chart is what is going to be discussed here.... Below is the graph of a pwht process. Lets start reading it.....(Here i am discussing on the understanding that you are a little bit familiar with the process....)
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
1/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
In this chart, http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
2/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
X-axis represents temperature and Y-axis represents Time. In X-axis each line to line distance represents 10Deg C (See it is written as X 100°C, that means in X axis, 2 means
2 X 100°C= 200°C, 3 means 3 X 100°C= 300°C etc.) In Y-axis each line to line distance represents half an hour. That means the time between 2 and 3 represents one hour. These are the basics. How to read the graph?
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
3/7
11/16/2016
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
4/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
The graph contains several lines, AB, BC, CD, AE 1 ) AB is RATE OF HEATING curve 2) BC is SOAKING TEMPERATURE 3) CD is RATE OF COOLING curve 4) AE is ROOM TEMPERATURE curve When you check the WPS you can see the required values for each of these. 1) AB: Rate of heating: In WPS it is mentioned as a maximum value. In the graph the rate of heating is the slope of the curve AB. So the value of the slope should not be more than the value in WPS. How to calculate the slope: Slope = kl/lm Now in the graph given above, for AB line, kl=80DegC and lm=1/2 hr slope = 80 / (1/2) = 160DegC/hr ; So in this graph the rate of heating is 160DegC/hr. 2) BC: Soaking Temperature: In WPS it is mentioned as a single value with some plus/minus allowance along with time it is to be steady(mentioned as minimum) Here in this graph it is 720Deg (Reading in X-axis) and for approximate 2hr and 10minute(this is an approximationReading in Y-axis )
3) CD: Rate of cooling: In WPS it is mentioned as a maximum value. In the graph the rate of heating is the slope of the curve CD. So the value of the slope should not be more than the value in WPS.
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
5/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
How to calculate the slope: Slope = qr/pq Now in the graph given above, for CD line, qr=130DegC and pq=45 Min(this is taken as an approximation from the graph.) slope = 130 / 45 = 2.89DegC/Min ; So in this graph the rate of heating is 173DegC/hr.
4) AE: Room Temperature: This is the room temperature, here it is 40 deg C. Loading Temperature: Loading temperature is the temperature at which controlled heating (maintaining the rate of heating in the WPS) starts, up to which there is no need for controlled heating. Unloading Temperature: Unloading temperature is the temperature up to which controlled cooling (maintaining the rate of cooling in the WPS) occurs, below which there is no need for controlled cooling.Normally the power connection is disconnected below the temperature, keeping the insulation. After getting cooled to the atmospheric temperature the insulation is removed. NB: Please check the speed of the chart movement in the PWHT machine, Normally it is 25mm/hr. -----------------------------------------------------------------------------------------------------------PWHT [PART-2]: http://hareeshkv.blogspot.com/2015/06/pwht-part-2-thermocouples.html
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
6/7
11/16/2016
PWHT - [Part 1] HOW TO READ A PWHT CHART - MECHANICAL CONSTRUCTION INDUSTRY
Induction Heating Systems Encur, Inc. is a worldwide leader in induction heating systems. Go to encur.com
Local Furnace Experts ExpressCoils - Buy Small Coils Beryllium Copper, Brass & More Hempel Firmus Metals Ltd - Coil, Sheet, Precision Strip
http://hareeshkv.blogspot.in/2012/11/how-to-read-pwht-chart.html
7/7
Related Documents 3m3m1z
Pwht - [part 1] How To Read A Pwht Chart - Mechanical Construction Industry 475j5p
November 2020 0
How To Read Pwht Chart 365431
December 2021 0
Pwht Procedure 1i1kt
November 2019 91
P91 Pwht 5l1v2g
December 2019 58
Pwht Procedure 1i1kt
November 2019 114
Pwht Of P91 273g4b
December 2019 56More Documents from "Sanket Patel" 6n2j66
Ic Engine Component Design 2u641o
November 2019 75
Land Ceiling 635y4v
December 2019 59
Shant Jarukhe Vaat Nirkhati Lyrics Gujarati Songs Lyrics - Latest Bollywood Movie Songs Lyrics 2015 , Hindi Songs Lyrics, Songs.pdf 2f6v3p
November 2019 422
Syllabus_b.p.ed 4254t
January 2021 0
Pwht - [part 1] How To Read A Pwht Chart - Mechanical Construction Industry 475j5p
November 2020 0