1) Digitally controlled, software based MIG welding equipment allows increased productivity and welding speed for stainless steels through adjustable welding parameters and pre-programmed curves.
2) Key features include synergic curves that adjust parameters automatically based on wire feed speed, adjustable arc characteristics like force and inductance, pulsed MIG options, and memory storage of settings.
3) Double pulse MIG welding provides benefits over standard pulsed MIG for aluminum welding by producing a smooth weld appearance resembling TIG welds through modulation of current, voltage, and wire feed speed.
This document provides an overview of gas metal arc welding (GMAW), also known as metal inert gas (MIG) welding. It discusses GMAW safety, the basic principles and components of the GMAW process, how to set up GMAW equipment, important welding variables, and the advantages of GMAW. Key aspects covered include the use of a solid wire electrode and shielding gas, the electric arc between the wire and workpiece, and how to adjust variables like wire feed speed, voltage, and gas flow rate.
Modeling of the Heating Sequences of Lightweight Steel/Aluminum Bimaterial Bi...Fluxtrol Inc.
Paper by:
Robert Goldstein Fluxtrol Inc., Auburn Hills, MI, USA
Bulent Chavdar Eaton, Southfield, MI, USA
Lynn Ferguson DANTE Solutions Inc., Cleveland, OH, USA
ABSTRACT:
In this paper, the concept studied is hot forged from a bimetal
billet, which is a steel tube press fit with a solid aluminum
core and welded shut with steel end caps. For the experimental
part of the studies Al 7075 was selected as the core material
due to its high strength to weight ratio and 1020 steel was
selected because of its availability as a tube. Induction heating
was selected as the heating method for bimetal forging. This
is due to the ability of induction heating to rapidly heat the
steel layer. Successful bimetal forging of a closed vessel
requires the steel layer to be in the austenite phase prior to the
aluminum reaching high temperatures to prevent
compromising the weld seams. Modeling of the induction
heating process is complex due to the dimensional movement
of components during the process. A method was developed
to accurately model the induction heating process and predict
power requirements. The method will be described and the
results of the models will be compared to experimental
findings. The forming process will be discussed in another
paper at the conference. The simulation presented is for solid
state forging of a steel aluminum billet, but the method for
modeling the process is the same for hot hydroforging or other
material combinations.
Experimental and Finite Element Analysis of Single-V Groove Butt Weld on Weld...IJSRD
Gas Tungsten Arc Welding Process (GTAW) is widely used in fabrication of Aluminium and Aluminium Alloy material when precision is considered as a prime importance. Deformations in the object undergoing welding are one of the foremost problems encountered in the welding industry. Thus it is often required to study the factors which affect the deformations produced during welding to avoid errors in the geometry. Present investigation highlights Experimental and Finite Element Analysis of a Single-V Groove Butt Weld on Weld Pool Geometry of Aluminium Alloy Plate under Different Joint Parameters.Finite Element Method (FEM) has been employed to do the transient thermal and structural analysis of the assembly. The Finite Element Analysis has been done on ANSYS 14.5 Workbench. Number of factors is liable to produce effects in the job during the welding operation. Aim of this paper is the effect of welding parameters like as welding current, shielding gas flow rate and welding speed with mechanical Properties like tensile strength and hardness. After that finite element analysis for temperature distribution and distribution of the stresses in the welded Aluminium alloy plate. The results show that the larger the Welding current and smaller welding speed will lead to the maximum residual tensile stress. Therefore a residual stress will arise from the restraint position. The ultimate residual stress of weldment is determined by material yield strength at different temperature. The higher yield strength at different temperature has higher material residual stress. Because of its higher thermal conductivity, aluminium alloy test specimens have small temperature differential.
The document experimentally analyzes chip-back temperature during machining at different cutting parameters. An embedded thermocouple method was used to measure the temperature at the back of the cutting tool. Tests were conducted on an AISI 1010 steel workpiece using varying cutting speeds, feed rates, and depths of cut. The results showed that increasing any of the cutting parameters led to higher measured temperatures, with cutting speed having the greatest influence. Temperatures increased more substantially at lower cutting speeds compared to higher speeds. Feed rate had a relatively smaller impact on temperature than the other parameters.
This document discusses bi-metallic thermometers. It begins with an introduction on the importance of temperature measurement. It then explains that a bi-metallic thermometer uses two metals with different coefficients of thermal expansion bonded together. As temperature changes, the strip bends due to the differential expansion of the metals. This movement is used to indicate the temperature. Key features discussed include the construction of the bi-metallic strip, how temperature causes it to bend, common metal combinations used, and applications in industrial processes and devices.
This document outlines the course contents for the subject Electrical Power Utilization for the 8th semester of the Bachelor of Electrical Engineering program at Gujarat Technological University. The course covers 5 main topics: 1) Electric Drives, including different types of motors, starting and speed control methods, and applications. 2) Electrical Traction, covering various traction systems, track electrification, mechanics of train movement, and traction motor characteristics. 3) Electrical Heating & Welding, including resistive, induction, arc and dielectric heating as well as different types of electric welding. 4) Electrolytic Processes, covering principles of electrolysis and applications like electroplating. 5) Illuminations, discussing types of lamps, lighting
This document discusses the bimetallic strip thermometer. It is constructed using two metal strips with different coefficients of thermal expansion welded together. As temperature changes, the strips expand at different rates, causing the bimetallic strip to bend. This bending is used to measure temperature in various types of bimetallic strip thermometers, including cantilever, spiral, and helix designs. Common applications include industrial temperature measurement. The thermometers are inexpensive, robust, and do not require a power source, but have lower accuracy and sensitivity than modern electronic sensors.
This document provides an overview of gas metal arc welding (GMAW), also known as metal inert gas (MIG) welding. It discusses GMAW safety, the basic principles and components of the GMAW process, how to set up GMAW equipment, important welding variables, and the advantages of GMAW. Key aspects covered include the use of a solid wire electrode and shielding gas, the electric arc between the wire and workpiece, and how to adjust variables like wire feed speed, voltage, and gas flow rate.
Modeling of the Heating Sequences of Lightweight Steel/Aluminum Bimaterial Bi...Fluxtrol Inc.
Paper by:
Robert Goldstein Fluxtrol Inc., Auburn Hills, MI, USA
Bulent Chavdar Eaton, Southfield, MI, USA
Lynn Ferguson DANTE Solutions Inc., Cleveland, OH, USA
ABSTRACT:
In this paper, the concept studied is hot forged from a bimetal
billet, which is a steel tube press fit with a solid aluminum
core and welded shut with steel end caps. For the experimental
part of the studies Al 7075 was selected as the core material
due to its high strength to weight ratio and 1020 steel was
selected because of its availability as a tube. Induction heating
was selected as the heating method for bimetal forging. This
is due to the ability of induction heating to rapidly heat the
steel layer. Successful bimetal forging of a closed vessel
requires the steel layer to be in the austenite phase prior to the
aluminum reaching high temperatures to prevent
compromising the weld seams. Modeling of the induction
heating process is complex due to the dimensional movement
of components during the process. A method was developed
to accurately model the induction heating process and predict
power requirements. The method will be described and the
results of the models will be compared to experimental
findings. The forming process will be discussed in another
paper at the conference. The simulation presented is for solid
state forging of a steel aluminum billet, but the method for
modeling the process is the same for hot hydroforging or other
material combinations.
Experimental and Finite Element Analysis of Single-V Groove Butt Weld on Weld...IJSRD
Gas Tungsten Arc Welding Process (GTAW) is widely used in fabrication of Aluminium and Aluminium Alloy material when precision is considered as a prime importance. Deformations in the object undergoing welding are one of the foremost problems encountered in the welding industry. Thus it is often required to study the factors which affect the deformations produced during welding to avoid errors in the geometry. Present investigation highlights Experimental and Finite Element Analysis of a Single-V Groove Butt Weld on Weld Pool Geometry of Aluminium Alloy Plate under Different Joint Parameters.Finite Element Method (FEM) has been employed to do the transient thermal and structural analysis of the assembly. The Finite Element Analysis has been done on ANSYS 14.5 Workbench. Number of factors is liable to produce effects in the job during the welding operation. Aim of this paper is the effect of welding parameters like as welding current, shielding gas flow rate and welding speed with mechanical Properties like tensile strength and hardness. After that finite element analysis for temperature distribution and distribution of the stresses in the welded Aluminium alloy plate. The results show that the larger the Welding current and smaller welding speed will lead to the maximum residual tensile stress. Therefore a residual stress will arise from the restraint position. The ultimate residual stress of weldment is determined by material yield strength at different temperature. The higher yield strength at different temperature has higher material residual stress. Because of its higher thermal conductivity, aluminium alloy test specimens have small temperature differential.
The document experimentally analyzes chip-back temperature during machining at different cutting parameters. An embedded thermocouple method was used to measure the temperature at the back of the cutting tool. Tests were conducted on an AISI 1010 steel workpiece using varying cutting speeds, feed rates, and depths of cut. The results showed that increasing any of the cutting parameters led to higher measured temperatures, with cutting speed having the greatest influence. Temperatures increased more substantially at lower cutting speeds compared to higher speeds. Feed rate had a relatively smaller impact on temperature than the other parameters.
This document discusses bi-metallic thermometers. It begins with an introduction on the importance of temperature measurement. It then explains that a bi-metallic thermometer uses two metals with different coefficients of thermal expansion bonded together. As temperature changes, the strip bends due to the differential expansion of the metals. This movement is used to indicate the temperature. Key features discussed include the construction of the bi-metallic strip, how temperature causes it to bend, common metal combinations used, and applications in industrial processes and devices.
This document outlines the course contents for the subject Electrical Power Utilization for the 8th semester of the Bachelor of Electrical Engineering program at Gujarat Technological University. The course covers 5 main topics: 1) Electric Drives, including different types of motors, starting and speed control methods, and applications. 2) Electrical Traction, covering various traction systems, track electrification, mechanics of train movement, and traction motor characteristics. 3) Electrical Heating & Welding, including resistive, induction, arc and dielectric heating as well as different types of electric welding. 4) Electrolytic Processes, covering principles of electrolysis and applications like electroplating. 5) Illuminations, discussing types of lamps, lighting
This document discusses the bimetallic strip thermometer. It is constructed using two metal strips with different coefficients of thermal expansion welded together. As temperature changes, the strips expand at different rates, causing the bimetallic strip to bend. This bending is used to measure temperature in various types of bimetallic strip thermometers, including cantilever, spiral, and helix designs. Common applications include industrial temperature measurement. The thermometers are inexpensive, robust, and do not require a power source, but have lower accuracy and sensitivity than modern electronic sensors.
This document discusses the bimetallic strip thermometer. It is made of two metal strips with different coefficients of thermal expansion welded together. When heated, the strips expand at different rates, causing the strip to bend. This movement can be used to measure temperature changes. The document covers the types, construction, working principle, metals used, advantages, disadvantages, and applications of the bimetallic strip thermometer.
IRJET- Review on Investigate the Tig Welding of Aluminum by Controlling Param...IRJET Journal
The document summarizes research on investigating parameters for TIG welding of aluminum. It begins with an abstract describing the goals of improving weld strength and quality for pure aluminum plates by controlling welding speed and arc length. Welding was performed in two phases, with single-side welding first and then double-side welding. Tensile strength, hardness, bead width, and depth of penetration were evaluated under different parameters. The document then reviews relevant literature and discusses input parameters like arc length, welding speed, current, and gas flow rate. It presents the effects of varying these parameters on weld properties. Finally, the literature review summarizes several studies investigating how controlling heat input through different currents affects microstructure and mechanical properties of aluminum wel
Bimetallic thermometers use the different rates of thermal expansion in two bonded metals to measure temperature. They consist of a bimetallic strip formed into a spiral or helix with the metals joined at one end. As temperature changes, the free end of the strip expands or contracts differently between the metals, causing it to deflect. This movement is used to drive a pointer indicating the temperature reading. While simple and inexpensive, bimetallic thermometers have limited accuracy but remain useful for industrial processes where manual temperature monitoring is sufficient.
This document discusses different types of bimetallic thermometers used for temperature measurement in industrial environments. It describes how bimetallic thermometers work using two metals with different coefficients of thermal expansion joined together. When temperature changes, the differential expansion causes the bimetallic strip to twist, rotating a pointer to indicate the temperature reading on a calibrated scale. Common configurations include a spiral strip or coil design to translate thermal expansion into rotational movement. While simple and inexpensive, bimetallic thermometers have limitations such as accuracy below 400°C and potential for permanent deformation over time.
Chapter 6: Fluxtrol Materials on Induction CoilsFluxtrol Inc.
http://fluxtrol.com
Chapter 6: Fluxtrol Materials on Induction Coils
Includes: 37 Fact Filled Slides of Process Improvement Technology and Materials utilizing Fluxtrol's 30 Years of Industry Serving Experience and Advanced Products.
Fluxtrol's "Best Practice for Design and Manufacturing of Heat Treating Induc...Fluxtrol Inc.
With the use of good design practices, one can improve coil longevity and improve production quality. By eliminating failure points in the initial design, proper material selection, improved cooling and proper magnetic flux control, induction tooling life can be increased. Computer simulation has been proven to be an effective tool for predicting not only electromagnetic parameters of a designed system, but also heat patterns in a given part and in the induction coil itself. When a coil has magnetic flux controllers present, their influence may also be predicted by computer simulation. With an extensive library of published case studies in induction coil design and performance evaluations, we are confident with the use of these tools and proper coil geometries and implementation, production life and quality can be improved on most induction heat treating inductors. These design practices have been used by the authors for over 20 years with proven results. A case is examined of a CVJ stem hardening coil, in which the principles discussed can be applied to most other hardening coils.
- Preheat can minimize cracking and/or ensure specific mechanical properties such as notch toughness. It must be used when codes specify and may be needed based on base metal, thickness, and other factors when no codes apply.
- Annex XI of AWS D1.1-96 provides two methods for determining proper preheat amounts: HAZ hardness control or hydrogen control.
- Preheat may be applied using furnaces, heating torches, electrical strip heaters, or induction/radiant heaters. Proper temperatures must be followed closely for quenched/tempered steels but not as critical for carbon steels.
This document summarizes various sheet metal processes. It discusses sheet metal characteristics and typical forming operations like shearing, bending, drawing, and stretching. It also covers special forming processes such as hydroforming, rubber pad forming, spinning, explosive forming and super plastic forming. The document provides details on sheet metal tools, presses, cutting and forming operations, factors affecting formability and various test methods used to evaluate formability.
Increasing Inductor Lifetime by Predicting Coil Copper Temperatures PaperFluxtrol Inc.
In recent years, there has been a significant increase in the customer demands for improved induction coil lifetime. This has led to several publications in recent years by induction tooling manufacturers [1-4]. The main conclusion in these papers is that besides mechanical crashes the cause of most induction coil failures is localized overheating of the coil copper due to insufficient cooling.
What is lacking from these publications is any way to determine what is sufficient cooling. In this paper, a scientific method for determining local copper temperatures will be presented. This will include evaluations of heat transfer coefficients for different sections of a multi-component inductor, dependence of heat transfer coefficient on water pressure and water passage cross-section, non-uniform power density distributions in various 2-D cross-sections and the resulting temperature distribution in the copper winding. The effects of duty cycle on optimal design will also be considered.
IPC-2152 is a new standard being developed to provide guidelines for determining the current carrying capacity of conductors in printed circuit board design. It includes testing data on how factors like environment, conductor width/thickness, PCB thickness, and materials affect temperature rise. Charts in the main document provide conservative guidelines for internal/external conductor sizing in air and vacuum. An appendix provides more detailed information and analysis. The goal is for IPC-2152 to replace the existing conductor sizing guidelines in IPC-2221 and continue being updated as understanding improves.
This document discusses temperature measurement and different temperature scales. It describes common temperature measurement devices including expansion thermometers, thermocouples, RTDs, thermistors, integrated circuits, optical pyrometers, and infrared thermometers. Expansion thermometers like mercury and alcohol thermometers measure temperature by detecting the thermal expansion of liquid. Thermocouples use the Seebeck effect to convert temperature differences to voltage. RTDs measure resistance changes in materials like platinum to determine temperature.
080930 Ipc 2152 Standard For Determining Current Carrying Capacityljh1680
IPC-2152 is a new standard being developed to provide guidelines for determining the current carrying capacity of conductors in printed circuit board design. It includes simplified charts as well as an appendix with more detailed information. The standard is based on industry testing of factors like conductor width/thickness, board thickness, environment and materials. It aims to replace the existing guidelines in another standard with more precise yet accessible recommendations.
Chapter 7: Fluxtrol Induction Heating Case Studies and Success StoriesFluxtrol Inc.
The document describes several case studies where Fluxtrol helped optimize induction heating processes by developing new induction coil designs and magnetic flux concentrator profiles. In each case, computer simulations identified issues with existing processes, and new coil designs with customized Fluxtrol concentrators achieved more uniform heating and resolved production problems. The optimized solutions improved part quality, increased production rates, and extended coil lifetimes.
Analysis of Cantilever Steel Chimney As Per Indian StandardsIJERA Editor
Chimneys are tall and slender structures which are used to discharge waste/flue gases at higher elevation with sufficient exit velocity such that the gases and suspended solids(ash) are dispersed in to the atmosphere over a defined spread such that their concentration , on reaching the ground is within acceptable limits specified by pollution control regulatory authorities. This paper summarizes the analysis and design concepts of chimneys as per Indian codal provisions incorporation was also made through finite element analysis. Effect of inspection manhole on the behavior of Cantilever steel chimney, two chimney models one with the manhole and other without manhole were taken into consideration. These models are analyzed by finite element software STAAD Pro, emphasis also placed on effect of geometric limitations on the design aspects in designing chimney.
Abstract Chimneys are very important structures for the emission of poisonous gases in power plants. After realising the urgent need to
restrict the pollution levels, chimney height is being rapidly increased. So most of the chimneys are tall slender structures which
fail due to wind excitation The present study discusses the dynamic behaviour of tall chimneys. Reinforced concrete chimney of
275m high, which is located in warora, Maharastra is taken for the present study. The objective of this project is to study the
change in the stress pattern due to presence of flue holes and also to carry out the influence of along wind and across wind effects
on the height of chimney for different wind speed and location. The analyse of chimney is carried out by developing a three
dimensional model created with plate elements using STADD Pro. The stress concentrations in the flue duct in the chimney have
been studied.
Keywords: Tall Slender, Warora, Maharastra, Flue Holes, STADD Pro, Stress Concentration
The document provides information on different types of welding processes including butt welding, spot welding, carbon arc welding, and metal arc welding. It also discusses induction furnaces, resistance heating, temperature control of resistance furnaces, and heat losses in furnaces. Some key points:
1) Butt welding involves clamping two metal pieces face to face and passing a current through electrodes to melt and fuse the metals. Spot welding uses electrodes to fuse sheet metals.
2) Carbon arc welding uses a carbon electrode to produce an arc for welding. Metal arc welding uses a consumable electrode to produce heat for welding via an electric arc.
3) An induction furnace uses electromagnetic induction to heat a metal charge. The
This ppt is made for making the topic clear. The aim is to make available content regarding thermocouple which is available on various sites. This ppt is made only for study purposes. The author doesn't claim originality of the content.
The thermocouple can be defined as a kind of temperature sensor that is used to measure the temperature at one specific point in the form of the EMF or an electric current. This sensor comprises two dissimilar metal wires that are connected together at one junction. A Thermocouple is a sensor used to measure temperature. Thermocouples consist of two wire legs made from different metals. The wires' legs are welded together at one end, creating a junction. The voltage can then be interpreted using thermocouple reference tables to calculate the temperature.The temperature can be measured at this junction, and the change in temperature of the metal wire stimulates the voltages. These are used as the temperature sensors in thermostats in offices, homes, offices & businesses.
These are used in industries for monitoring temperatures of metals in iron, aluminum, and metal.
These are used in the food industry for cryogenic and Low-temperature applications. Thermocouples are used as a heat pump for performing thermoelectric cooling.
These are used to test temperature in the chemical plants, petroleum plants. These are used in gas machines for detecting the pilot flame.
IRJET- Performance Improvement of PCM Assisted Heat PipeIRJET Journal
1) The document describes an experiment to improve the performance of a heat pipe assisted by phase change material (PCM) by introducing metal rings into the PCM.
2) PCM provides additional heat absorption and storage compared to a normal heat pipe, but has low thermal conductivity, limiting heat transfer.
3) The researchers introduced metal rings with higher thermal conductivity than the PCM material to increase the surface area in contact with the PCM and thereby increase the heat transfer rate from the heat pipe into the PCM.
4) Testing showed that the modified heat pipe with metal rings improved performance by 9.38% compared to the heat pipe without metal rings.
Temperature is a measure of the average kinetic energy of particles in a sample of matter. It can be measured using various devices that operate based on the principle of expansion and contraction of materials with changes in temperature. Common temperature measurement devices include liquid-in-glass thermometers, bimetallic strips, thermistors, thermocouples, and RTDs. Each device has its own advantages and limitations in terms of measurement range, accuracy, response time, cost, and other factors. Radiative pyrometers can measure very high temperatures by detecting the wavelength of thermal radiation emitted by the object.
This document provides an overview of gas metal arc welding (GMAW), also known as metal inert gas (MIG) welding. It discusses GMAW safety, the basic principles and components of the GMAW process, how to set up GMAW equipment, important welding variables, and the advantages of GMAW. Key aspects covered include the use of a solid wire electrode and shielding gas, the electric arc between the wire and workpiece, and how to adjust variables like wire feed speed, voltage, and gas flow rate.
Mig welding process is semi automatic when used for manual welding . It can be used in welding automation systems for high quality welds and high productivity.
This document discusses the bimetallic strip thermometer. It is made of two metal strips with different coefficients of thermal expansion welded together. When heated, the strips expand at different rates, causing the strip to bend. This movement can be used to measure temperature changes. The document covers the types, construction, working principle, metals used, advantages, disadvantages, and applications of the bimetallic strip thermometer.
IRJET- Review on Investigate the Tig Welding of Aluminum by Controlling Param...IRJET Journal
The document summarizes research on investigating parameters for TIG welding of aluminum. It begins with an abstract describing the goals of improving weld strength and quality for pure aluminum plates by controlling welding speed and arc length. Welding was performed in two phases, with single-side welding first and then double-side welding. Tensile strength, hardness, bead width, and depth of penetration were evaluated under different parameters. The document then reviews relevant literature and discusses input parameters like arc length, welding speed, current, and gas flow rate. It presents the effects of varying these parameters on weld properties. Finally, the literature review summarizes several studies investigating how controlling heat input through different currents affects microstructure and mechanical properties of aluminum wel
Bimetallic thermometers use the different rates of thermal expansion in two bonded metals to measure temperature. They consist of a bimetallic strip formed into a spiral or helix with the metals joined at one end. As temperature changes, the free end of the strip expands or contracts differently between the metals, causing it to deflect. This movement is used to drive a pointer indicating the temperature reading. While simple and inexpensive, bimetallic thermometers have limited accuracy but remain useful for industrial processes where manual temperature monitoring is sufficient.
This document discusses different types of bimetallic thermometers used for temperature measurement in industrial environments. It describes how bimetallic thermometers work using two metals with different coefficients of thermal expansion joined together. When temperature changes, the differential expansion causes the bimetallic strip to twist, rotating a pointer to indicate the temperature reading on a calibrated scale. Common configurations include a spiral strip or coil design to translate thermal expansion into rotational movement. While simple and inexpensive, bimetallic thermometers have limitations such as accuracy below 400°C and potential for permanent deformation over time.
Chapter 6: Fluxtrol Materials on Induction CoilsFluxtrol Inc.
http://fluxtrol.com
Chapter 6: Fluxtrol Materials on Induction Coils
Includes: 37 Fact Filled Slides of Process Improvement Technology and Materials utilizing Fluxtrol's 30 Years of Industry Serving Experience and Advanced Products.
Fluxtrol's "Best Practice for Design and Manufacturing of Heat Treating Induc...Fluxtrol Inc.
With the use of good design practices, one can improve coil longevity and improve production quality. By eliminating failure points in the initial design, proper material selection, improved cooling and proper magnetic flux control, induction tooling life can be increased. Computer simulation has been proven to be an effective tool for predicting not only electromagnetic parameters of a designed system, but also heat patterns in a given part and in the induction coil itself. When a coil has magnetic flux controllers present, their influence may also be predicted by computer simulation. With an extensive library of published case studies in induction coil design and performance evaluations, we are confident with the use of these tools and proper coil geometries and implementation, production life and quality can be improved on most induction heat treating inductors. These design practices have been used by the authors for over 20 years with proven results. A case is examined of a CVJ stem hardening coil, in which the principles discussed can be applied to most other hardening coils.
- Preheat can minimize cracking and/or ensure specific mechanical properties such as notch toughness. It must be used when codes specify and may be needed based on base metal, thickness, and other factors when no codes apply.
- Annex XI of AWS D1.1-96 provides two methods for determining proper preheat amounts: HAZ hardness control or hydrogen control.
- Preheat may be applied using furnaces, heating torches, electrical strip heaters, or induction/radiant heaters. Proper temperatures must be followed closely for quenched/tempered steels but not as critical for carbon steels.
This document summarizes various sheet metal processes. It discusses sheet metal characteristics and typical forming operations like shearing, bending, drawing, and stretching. It also covers special forming processes such as hydroforming, rubber pad forming, spinning, explosive forming and super plastic forming. The document provides details on sheet metal tools, presses, cutting and forming operations, factors affecting formability and various test methods used to evaluate formability.
Increasing Inductor Lifetime by Predicting Coil Copper Temperatures PaperFluxtrol Inc.
In recent years, there has been a significant increase in the customer demands for improved induction coil lifetime. This has led to several publications in recent years by induction tooling manufacturers [1-4]. The main conclusion in these papers is that besides mechanical crashes the cause of most induction coil failures is localized overheating of the coil copper due to insufficient cooling.
What is lacking from these publications is any way to determine what is sufficient cooling. In this paper, a scientific method for determining local copper temperatures will be presented. This will include evaluations of heat transfer coefficients for different sections of a multi-component inductor, dependence of heat transfer coefficient on water pressure and water passage cross-section, non-uniform power density distributions in various 2-D cross-sections and the resulting temperature distribution in the copper winding. The effects of duty cycle on optimal design will also be considered.
IPC-2152 is a new standard being developed to provide guidelines for determining the current carrying capacity of conductors in printed circuit board design. It includes testing data on how factors like environment, conductor width/thickness, PCB thickness, and materials affect temperature rise. Charts in the main document provide conservative guidelines for internal/external conductor sizing in air and vacuum. An appendix provides more detailed information and analysis. The goal is for IPC-2152 to replace the existing conductor sizing guidelines in IPC-2221 and continue being updated as understanding improves.
This document discusses temperature measurement and different temperature scales. It describes common temperature measurement devices including expansion thermometers, thermocouples, RTDs, thermistors, integrated circuits, optical pyrometers, and infrared thermometers. Expansion thermometers like mercury and alcohol thermometers measure temperature by detecting the thermal expansion of liquid. Thermocouples use the Seebeck effect to convert temperature differences to voltage. RTDs measure resistance changes in materials like platinum to determine temperature.
080930 Ipc 2152 Standard For Determining Current Carrying Capacityljh1680
IPC-2152 is a new standard being developed to provide guidelines for determining the current carrying capacity of conductors in printed circuit board design. It includes simplified charts as well as an appendix with more detailed information. The standard is based on industry testing of factors like conductor width/thickness, board thickness, environment and materials. It aims to replace the existing guidelines in another standard with more precise yet accessible recommendations.
Chapter 7: Fluxtrol Induction Heating Case Studies and Success StoriesFluxtrol Inc.
The document describes several case studies where Fluxtrol helped optimize induction heating processes by developing new induction coil designs and magnetic flux concentrator profiles. In each case, computer simulations identified issues with existing processes, and new coil designs with customized Fluxtrol concentrators achieved more uniform heating and resolved production problems. The optimized solutions improved part quality, increased production rates, and extended coil lifetimes.
Analysis of Cantilever Steel Chimney As Per Indian StandardsIJERA Editor
Chimneys are tall and slender structures which are used to discharge waste/flue gases at higher elevation with sufficient exit velocity such that the gases and suspended solids(ash) are dispersed in to the atmosphere over a defined spread such that their concentration , on reaching the ground is within acceptable limits specified by pollution control regulatory authorities. This paper summarizes the analysis and design concepts of chimneys as per Indian codal provisions incorporation was also made through finite element analysis. Effect of inspection manhole on the behavior of Cantilever steel chimney, two chimney models one with the manhole and other without manhole were taken into consideration. These models are analyzed by finite element software STAAD Pro, emphasis also placed on effect of geometric limitations on the design aspects in designing chimney.
Abstract Chimneys are very important structures for the emission of poisonous gases in power plants. After realising the urgent need to
restrict the pollution levels, chimney height is being rapidly increased. So most of the chimneys are tall slender structures which
fail due to wind excitation The present study discusses the dynamic behaviour of tall chimneys. Reinforced concrete chimney of
275m high, which is located in warora, Maharastra is taken for the present study. The objective of this project is to study the
change in the stress pattern due to presence of flue holes and also to carry out the influence of along wind and across wind effects
on the height of chimney for different wind speed and location. The analyse of chimney is carried out by developing a three
dimensional model created with plate elements using STADD Pro. The stress concentrations in the flue duct in the chimney have
been studied.
Keywords: Tall Slender, Warora, Maharastra, Flue Holes, STADD Pro, Stress Concentration
The document provides information on different types of welding processes including butt welding, spot welding, carbon arc welding, and metal arc welding. It also discusses induction furnaces, resistance heating, temperature control of resistance furnaces, and heat losses in furnaces. Some key points:
1) Butt welding involves clamping two metal pieces face to face and passing a current through electrodes to melt and fuse the metals. Spot welding uses electrodes to fuse sheet metals.
2) Carbon arc welding uses a carbon electrode to produce an arc for welding. Metal arc welding uses a consumable electrode to produce heat for welding via an electric arc.
3) An induction furnace uses electromagnetic induction to heat a metal charge. The
This ppt is made for making the topic clear. The aim is to make available content regarding thermocouple which is available on various sites. This ppt is made only for study purposes. The author doesn't claim originality of the content.
The thermocouple can be defined as a kind of temperature sensor that is used to measure the temperature at one specific point in the form of the EMF or an electric current. This sensor comprises two dissimilar metal wires that are connected together at one junction. A Thermocouple is a sensor used to measure temperature. Thermocouples consist of two wire legs made from different metals. The wires' legs are welded together at one end, creating a junction. The voltage can then be interpreted using thermocouple reference tables to calculate the temperature.The temperature can be measured at this junction, and the change in temperature of the metal wire stimulates the voltages. These are used as the temperature sensors in thermostats in offices, homes, offices & businesses.
These are used in industries for monitoring temperatures of metals in iron, aluminum, and metal.
These are used in the food industry for cryogenic and Low-temperature applications. Thermocouples are used as a heat pump for performing thermoelectric cooling.
These are used to test temperature in the chemical plants, petroleum plants. These are used in gas machines for detecting the pilot flame.
IRJET- Performance Improvement of PCM Assisted Heat PipeIRJET Journal
1) The document describes an experiment to improve the performance of a heat pipe assisted by phase change material (PCM) by introducing metal rings into the PCM.
2) PCM provides additional heat absorption and storage compared to a normal heat pipe, but has low thermal conductivity, limiting heat transfer.
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The process GMAW with its your applications using two wires pointing in the market as an alternative to coating when high productivity is desired. Potential variants emerge from this process as GMAW cold wire and GMAW double wire. One of the biggest difficulty is the setting of its parameters, which in addition to duplicate compared to conventional GMAW, act in a dependent manner. A greater understanding of this technology applied to coatings on turbines in various positions is critical so that you can master the process and its variables, aiming to enhance the application in industry. It was proposed in this study an experimental evaluation to verify the influence of some variables on the profile of cord and wear resistance. For this it is proposed in this paper to make deposits with weld metal AWS 308LSi stainless steel and alloys of cobalt (Stellites 6 and 21) plates in carbon steel SAE 1020 in flat positions. In the characterization of wear in the lining was used the determination of the hardness and surface topography. It is concluded that cobalt alloys have superior resistance to erosive damage with emphasis on the Stellite 21 alloy in erosion and cavitation in Stellite 6. In an intermediate position with respect to wear are mixtures of austenitic stainless steel and cobalt alloys. Therefore, it is essential to study welding processes with multiple wires as proposed in this paper aiming the best combination of alloys for resistance to cavitation-erosion phenomena.
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The document discusses Tungsten Inert Gas (TIG) welding for constructing an effective load bearing structure. Butt joints were used due to their strength and resistance to impact and stress. TIG welding provides high quality welds through manual operation and requires skill. Key parameters like current, voltage, gas flow and composition, and welding speed must be optimized. TIG welding has advantages like versatility, minimal distortions, and precise control and is often used for thin materials and in industries like aerospace, bicycle, and tool and die repair.
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1) The document provides information on manual metal arc (MMA) welding, including electrode selection, welding techniques, joint preparation, and consumables. It discusses factors for successful MMA welding such as electrode selection, current, arc length, and travel speed.
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Similar to INCREASED PRODUCTIVITY AND SPEED WITH DIGITALLY CONTROLLED SOFTWARE BASED MIG WELDING EQUIPMENT (20)
INCREASED PRODUCTIVITY AND SPEED WITH DIGITALLY CONTROLLED SOFTWARE BASED MIG WELDING EQUIPMENT
1. INCREASED PRODUCTIVITY AND SPEED WITH DIGITALLY CONTROLLED
SOFTWARE BASED MIG WELDING EQUIPMENT
Mr. Aarno Laine
M/S KEMPI OY., Finland
Introduction
The MIG/MAG/Pulsed MIG welding process has been developed to increase
productivity. The starting point has been to develop the welding characteristics so that
TIG and MMA welding can be replaced with a more economical and productive method.
New characteristic curves have been added to the welding range of stainless steels so that
even rarer steel qualities can be welded with standard programs.
Digitally Controlled-welding machine has been developed for demanding welding of
stainless steels. This is made possible by digital control technology both in the power
source and in the wire feeder. This makes it possible to update the equipment with new
programs and characteristics whenever necessary.
Synergic 1 – Knob welding:
As is well known, the welding process involves a large number of welding parameters. In
digitally controlled, software based machines the welding parameters change with the
wire-feed speed. This makes it easier to set the correct values in different welding
situations and it makes simple to repeat the correct settings.
The type of equipment can be used to weld all stainless solid and flux cored wires. The
share of flux cored wires in the welding of stainless steel has been increasing for years
already. Because, MIG welding is widely accepted for the welding of demanding
stainless targets in the industrial countries, the use of solid wire is becoming the
established method in the welding of ordinary stainless steels.
With solid wires the shielding gas is usually Ar+2%CO2 and with flux cored wires Ar+8-
25%CO2.
There is some machine, which has 13 pre-programmed synergic MAG curves for
stainless steels. Each curve consists of 14 parameters affecting the arc and the weld.
2. One of the most important parameters affecting the burning of the arc is the behaviour of
the short-circuit current, i.e., the arc-force in the short–arc and mixed-arc ranges. In the
traditional welding machines with step-wise adjustment, the inductance is selected by
setting the output of the earth cable from the choker. In some machine microprocessor
calculates and adjusts the set rate of change of the current of the arc in the short circuit
and keeps the arc at the desired length.
Example: welding parameters with the most common wire/gas combination 1.0mm /
316L / Ar+2%CO2
Arc force and inductance:
Depending on the circumstances, such as tolerances (composition of the wire, purity of
the gas, etc.), the digitally controlled software based welding machine gives the welder
the possibility to change the shape of the pulse to fit the circumstances. In addition the
welder can then change the behavior of the arc as he likes.
The coarseness or softness of the arc can be increased from the standard setting in the
short-arc and mixed-arc ranges.
A soft arc does not cause as much spatter as a coarse arc, but, on the other hand, it is
sensitive (more unstable) to movements of the hand and it uses a higher temperature.
3. A coarse arc is stable to weld (it allows the welder to push melt for example against the
root backing), but it easily causes spatter. The arc is also colder so that thin-sheet welding
succeeds even with high values and welding is faster.
Pulsed MIG welding:
Pulsed MIG welding is best suited for welding stainless steel with a solid wire.
The shield gas Ar+2%CO2 is the most common with solid wire, and in special cases an
addition of helium is necessary to increase weldability. Also other gas mixtures can be
used.
Some digitally controlled, software based machine has 16 pre-programmed synergic
pulsed MIG curves for stainless steels. Each curve consists of 16 parameters affecting the
arc and the welding.
In pulsed MIG welding the timing and shape of the current pulse is important so that the
filler material melts into the weld pool evenly and without spatters.
Increased productivity and speed:
Example : welding parameters with the most common wire/gas combination 1.0 mm
/ 316L / Ar+2%CO2 :
4. Adjustment of pulse height:
Because the circumstances involve several parameters (composition of the wire, purity of
the gas, etc.), digitally controlled machine also makes it possible to change the form of
the pulse to suit the circumstances.
High pulse is needed when the drops do not separate easily as with high-nickel filler
wires or if an easily targeted arc is desired. Too high a pulse will disperse the drops and
cause Micronics spatter.
A lower pulse is used when the drops separate easily, for example with a lower CO2
addition in the shield gas. The targeting of the arc is not as good as with a higher pulse.
Too low a pulse cannot separate the filler drop, so that it is transferred to the weld pool
through the short circuit or in the form of coarse spatter.
Cable compensation :
The length of the cables affects the length of the arc, which means that it has to be
taken into account. When cable length increases, so does the voltage drop to the
cables, which is compensated for by correspondingly increasing the voltage of the
power source. Automatic calibration makes it easier to adjust the voltage increase.
Use of the memory :
The memory channels makes it possible to find the settings again quickly and exactly. In
addition, when using the gun / remote control, they make it possible to find 5 different
welding values even during welding.
The display of the synergic panel shows the set welding values, and values used during
the welding can be recalled by means of the “weld data” – button so that the values can
be transferred for example to the WPS.
5. The sheet thickness table gives the preliminary welding values for the butt weld.
The selection windows of the synergic curve specify the filler material being used, the
gas, the diameter and the detailed curve number.
Customer specific programs:
The welding parameter can be changed when needed. The synergic curves are changed
through a PC by using the window based MIG Prog. Programme and a DLI interface.
This makes it possible for example to change the texts in the menu displays so that they
are more suitable to the customer’s needs and they even make it possible to create a
synergic curve for a new wire. They can be stored in the user function menu reserved for
the customer.
Any necessary new curves can also be added from the curve bank.
Welding characteristics:
The welding characteristics of digitally controlled software based machine sometime
tailored specifically for stainless steel. The ignition of the arc is one of the most important
stages in welding, because poor ignition creates a lot of spatter and even defective joins at
the start of the weld. In this type of machine ignition is extremely good because of the
high slope-up of the start current and the sufficient heat input.
Attention has also been paid to the burning of the arc as well as to the pointing of the arc
and to its tolerance to disturbances, which is seen well in position welding and specially
in pulse welding.
In the user mode it is possible to change the standard settings, for example the start and
end function, such as the creep start, the hot start function, the crater filling time and the
end level. It is easy to return to the standard settings.
Double pulse and aluminium welding
Difference between the ordinary pulse and double pulse:
Pulse MIG welding in simplest terms is achieved by varying the welding current
between background and peak current within a desired frequency range. To
achieve arc stabilization for any given filler wire and the shielding gas
combination, there are close to 20 parameters that optimize the current waveform,
which include dedicated parameters for controlling the peak and background
6. current. During the peak time one droplet of filler material is detached and
transferred across the open arc into the weld pool.
The background current is kept to a level at which the arc does not extinguish and
no filler material is detached. The pulsed frequency normally varies between 50
and 250 Hz and equalizes the burn off rate of the filler wire to give a constant arc
length without short-circuits. To simplify the use of the welding machine, there are
ready-made programs commonly known as synergic curves, saved in its memory
for different materials, materials thickness, wire diameter and the shielding gases.
To the user this means the setting of the correct welding parameters to achieve the
desired heat input is defined with just one main wire-feed speed control with fine-
adjustment of the arc-length. Commonly known as “one knob control”. Pulse
welding has been used to join the materials, as it welds at cooler temperatures. In
other words, it has lower energy input. This prevents burning through and the
excess heating of the background of the sheet. Distortions in welding are minor
and the welding does not cause spatter as the filler metal is transferred without
short-circuits. Managing the molten metal is made easier, especially in position
welding. In double pulse welding, the welding current and the wire feed speed are
pulsed. In addition, the pulsing of the current moves within the frequency defined
as a set value, at the minimum and the minimum and maximum current level of
normal pulsing, to a higher level, as can be seen in Figure 2. The frequency, the
number of times per second the pulsing moves to the higher level, can be selected
in the Set Up function on the function panel between 0.1-3 Hz. In figure 2, this
change happened twice. At the same time, the voltage rises. The energy of the arc
thus grows during the double pulse period compared to the basic pulse level. As
the energy changes, the melting power also changes. In normal pulse welding, the
wire feed is set to the desired value and the welding begins. When welding with
double pulse, in addition to the wire feed speed (for example 10 m/min), the
amplitude for the wire feed is also defined. This amplitude defines the minimum
and maximum value of the wire feed speed during the double pulse period. In case
of figure 2, the set values of the wire feed was 10 m/min and the amplitude 2.0,
7. and thus the wire feed varied between 8 m/min and 12 m/min during welding. In
other words, the wire feed pumps during welding. The result is visible as a weld
surface that resembles TIG welding, as presented in figure 3.
Using double pulse in aluminium welding
The main purpose of the double pulse machine is to refine and extend the benefits
brought by conventional synergic pulse thus simplifying welding, with greatly
improved welding quality. When welding aluminium, this means the weld is
faultless with an appearance resembling that of TIG welding, so often desired
when welding thin materials, such as those in bicycles and furniture. When
production-welding aluminium, the most common welding defects are porosity,
poor fusion, undercuts and cracks at the end of the weld. Poor fusion is often
caused by poor working technique, resulting in insufficient arc energy to melt the
base metal and remove an oxide layer whose melting points is 2,052 degree C.
Moreover, the deficiency in arc energy is emphasized by the rapid heat
conductivity of the base metal. On the other hand, the low melting point of
aluminium is visible as excessive melting of the base material, resulting in an
under-cut or burn through next to the weld. Cracking phenomena in welds are
mainly related to the choice of filler metal and to the performance of the welding.
The correct choice of the filler metal according to the base metal can be made with
help of various aluminium standers or tables from filler metal suppliers. The
porosity of the weld is mainly due to hydrogen that has entered the weld for a
variety of reasons. Dominant factors include cleanliness, the welding process,
groove preparation, the performing of the welding and the composition of the base
filler metals. For example, AIMg4, 5Mn is easier to weld in terms of porosity than
AIMgSi1, which is often used in extrusions.
Double pulse welding of the thin materials (1 - 5 mm)
The greatest benefits of double pulse with thin materials include good weldability
and the appearance of the weld. These benefits are emphasized in position
welding. Straight-line moving is used in welding. Quick oscillation, normally used
8. with aluminium, is not needed. These facilitates control of the weld pool in the
fillet corner.
As a result of the pumping of the arc, typical to double pulse, the appearance of
the weld resembles TIG welding. The pumping of the arc also affects the practical
performance of the welding. During the double pulse period, the arc energy and
the wire feed speed grow and enable sufficient penetration of the base metal.
When returning to the basic pulse, what we might call a deceleration phase, the
length of the arc shortens and the welding becomes slower and steadier. This is an
advantage when the root opening in the groove varies, as the risk of burning
through is reduced. In practice, welders feel they get more time to control the
molten metal. As it is a case of pulse welding, the material moves in drops without
short-circuits or splattering. Table 1 presents the double pulse welding parameters
for different aluminum thickness, the wire feed speed and its amplitude, and the
frequency of the double pulse. As basic instruction for welding thin materials, it
can be stated that the frequency of the double pulse to be used it increased and
amplitude of the wire feed-in reduced as the material thickness decreases.
Double Pulse Welding of Thicker Materials
Good weldability and appearance are also important in welding thicker materials.
In structures in which the material thickness is more than 5mm, the benefits of the
methods also very much include the evaluation both of penetration and formation
of gas pores. With double pulse welding, the depth of penetration can be changed
using amplitude and frequency. This is also visible in macrograph in figure 4. In
case presented in figure 4b, 15 mm Al 6082-T6 material has been welded using
double pulse. The size of the fillet is 5 mm. With the current selection of the
parameter, the energy of the arc reaches the level at which welding and control of
molten metal is easy and energy of the arc is sufficient to melt the fillet corner
without preheating. As end-result similar to figure 4a, achieved with the basic
pulse, appear to be good, but the energy has been insufficient to melt the base
9. metal enough. It is also possible to use double pulse in end welding. When
welding on one side against a ceramic backing in a root opening of 4 mm, double
pulsing and moving the gun in a straight line facilitate the welding. Particularly in
horizontal welding, the controlling of the top of the groove becomes easier. The
same regularity applies to the formation of the gas pores as with other current
forms. In the test that aimed at comparing the occurrences of gas pores in welds, 6
mm of aluminium AIMgSi1 (A16082-T6) was welded in a horizontal position
against a ceramic backing in a root opening of 4mm. In X-ray taken of the welds,
the gas pores were smaller and more evenly distributed in the weld than with the
normal pulse.