Infrared Heaters - Star Progetti Heating Systems User Guide Helios Electric Infrared IRK
Gas Infrared Heating Systems
-
Upload
anil-prajapati -
Category
Documents
-
view
40 -
download
0
description
Transcript of Gas Infrared Heating Systems
An Overview on Gas Infrared Heating Systems
30/07/2010
Kerone (Brief History)
Began in 1976, grew with 34 yrs of experience in the Heating Industry.
An ISO 9001-2008 Company
Kerone provides customized solutions in the field of heating.
Specialize in : Industrial heating Equipments, Automation systems,Infra-red Equipments ( Gas fired and electrical), Process control systems.
Exports to developed countries like US, UK, Germany, Australia,etc.
Have a widespread customer base in other applications like auto manufacturing, paper&board, paper/ plastic conversion, rubber, plastic, leather, textiles, glass, food, consumer products and general engineering.
What is Infrared (IR) ?
IR is a part of Electromagnetic Spectrum
Invisible
Travels at the speed of light
Can be directed
Can travels in Vacuum
No medium like Air is required to heat a
substance
Industrial heating: wavelength begins at 0.7µ up
to 10µ
Spectral Distribution of Energy for various of
IR sources
SW: 1800 - 2200 °C
FMW: 1200 - 1800 °C
MW: 750 - 1200 °C
LW: up to 650 °C
Advantages of IR heating
High energy efficiency
Improved quality due to non-contact heating
Fast response of the Emitters
Faster heat (Shorter time cycle)
Space Saving
Controllability and Control accuracy
Flexibility
MFB Gas IR Burners
Proposed for L&T (HED)
MFB (Metal Fibre Burners)
Unbreakable, very high life
Short heat-up and cool-down time (3- 4 secs)
Uniformity of radiation
Flexibility of Shape
Thermal & Mechanical Shock proof
Types:
MFB cloth 100 - Low Density 1.5 Kg/m2 , blue flame application
Sintered Mat 200/ Knitted Mat 250 - medium Density 2.5Kg/m2,
Radiant application
MFB Consists of..
Special alloy mat of Low Thermal mass
SS304 Plenium body
Thin perforated sheet supporting the mat
Diverters are used for equal distribution of premix
Gas entry is either from back or from side
Sintered Mat Burner
Knitted Mat 250,high density 4Kg/m2 is
used for consistently high temperature
applications.
Mat can be welded between housing and
flange
Rest of the construction is same as the
MFB design as described in previous
slide.
MFB Operation
Burner can be fired in 3 directions: up, down & sideways with some CARE
Vertically it can be fired with no loss of uniformity till a heated length of 1000mm.
Atmospheric firing :
Inexpensive, Less modulation Capacity.
Possible only if pressure of 120 mbar is available.
Firing Gas-Air Premix:
Requires Paraphernalia, higher modulation range and can work with Low pressures. (typical 20 - 40 mbar)
For long term reliability – addition of Gas train is required.
Important Note – Gas Combustion
Composition of Gas is the most Important parameter in designing a safe system.
Installation is set for a particular type of gas.
Variation in this can cause safety hazards.
Eg: Butane used in a system designed for propane or natural gas, flashback or explosion can occur.
Chemistry of Combustion
Generally CO2 and H2O are formed as byproducts of combustion of
hydrocarbons.eg..
CH4 + ½ O2 = CH3OH
CH3OH + ½ O2 = HCHO*+H2O
HCHO = CO+H2
H2 + ½ O2=H2O
CO + ½ O2=CO2
* This is formaldehyde. If the mix hits cold wall, the process stops here.
This is why formaldehyde smell is observed in a poorly designed
heat exchanger.
Gas : Air
λ = stoichiometric ratio = 1 if air is just
adequate for combustion
λ > 1 if air is excess
λ < 1 if gas is excess
Flame Modes
Radiant Mode : Premix flows such that heat
intensity is in the range of 100-500W/m2.
Most of the Combustion takes place within the burner surface.
This heats the surface, glows and transfers the heat in radiant form. This is Infrared mode.
Surface temp. is highest at 1050 ºC.
λ = 1.05 to 1.1
Blue Flame Mode: If premix quantity is increased ,
the burner cools down due to excess nitrogen flow.
Combustion takes place outside the burner. This is blue flame mode
Here the heat transfer is in convection mode.
Intensity is as high as 20MW/m2
λ = 1.1 to 1.2
Efficiency in Radiant Mode
At Lower intensities – higher combustion within surface
Around 125KW/m2 – radiant efficiency is highest ( approx 55 -60 %)
Below 100KW/m2 – Flame cannot be sustained.
Efficiency is high in face down position, it can be increased in any position by adding a grid in front.
MFB Gas IR Burners – Flexibility in
Design
Advantages of MFB Burners over
convection Gas Burners
Operates at low Gas pressure
Low Pressure drop
Low CO/NOX emissions, clean Heating
Homogeneous combustion with Modulation rate
Energy efficient
Safest design because of the flashback arrestors, much
safer than the household connections
Noise-free combustion, below < 500 KW/m
Tour to Gas IR Burners
GAS IR BURNER SYSTEM
FOR LONG SEAM WELDING
GAS IR BURNER SYSTEM
FOR LONG SEAM WELDING
GAS IR BURNER SYSTEM
FOR CIRCUMFERENTIAL SEAM WELDING
GAS IR BURNER SYSTEM
FOR CIRCUMFERENTIAL SEAM WELDING
PORTABLE CONTROL PANEL/GAS TRAIN
TROLLEY OF BURNER HEATING SYSTEM
(PLC Controlled)
Actual View of Circular Seam Gas IR Pre-
Heating Systems
Actual View of Circular Seam Gas IR Post- Heating
Systems
Thank you