Metall englisch - Kromschroder UK gas controls

Heat treatment
systems in the
metalworking industry
Edition 06.07 · GB
www.kromschroeder.com
2 · Kromschröder
Heat treatment systems in the metalworking industry · Edition 06.07
Walking beam furnace
LOI Thermprocess works photograph
Continuous pusher-type furnace
Ipsen works photograph
Innovation that pays
Optimum value for money
Kromschröder offers technically optimised
concepts for your process engineering applications in the metallurgical
industry with good value for money.
Safety, lower energy consumption and active
environmental protection are issues of utmost
importance for operators of industrial furnaces.
Kromschröder System
Technology CD-ROM
Catalogue CD-ROM
with Product Selection and Docuthek
Safety
Kromschröder gas control and safety systems often do more than make industrial
gas installations safe. They provide operating personnel with optimum protection to
a much higher level than is required by
the relevant standards and regulations.
System solutions
High quality in heat treatment processes is achieved with adapted systems designed by Elster Kromschröder.
Fieldbus components which are able to
communicate control these systems.
Existing systems can therefore be modernised and extended easily and at low cost.
Docuthek DVD
Spare parts list CDROM “PartDetective”
Technical
documentation
Modular design
The specially coordinated product range
offers excellent modular design options.
For years now, we have been very successful in taking these important steps
into the future of the modular element
system in industrial firing systems.
Gas types
All Kromschröder systems are suitable
for natural gas, town gas and LPG. In
addition, we can supply a large assortment of reliable gas controls for sewage
gas, landfill gas, biologically produced
methane, generator gas and coal gas.
Easy commissioning
Kromschröder systems are a key costcutting factor because they are easy
to assemble and install. Commissioning procedures are accordingly short
and straightforward. We also offer a
special range of courses for various
customer and product groups, should
you require extra support. Our competent Service Team is also there to help.
High availability thanks to
first-class service
The design and robust construction of the
Kromschröder firing systems ensure a long
service life. Preventive maintenance is a
prerequisite for perfect operation, high
availability and economy. For this reason,
our Service Team can offer you individually tailored maintenance contracts.
Extensive technical documentation
Brochures and operating instructions in
several languages, planning folders and
the Kromschröder System Technology
CD-ROM ensure easy handling of our
diversified product range – from manual
valves, gas filters and gas pressure regulators etc. to all-in system solutions. You
can download up-to-date Kromschröder
information from the Internet at any time.
www.kromschroeder.com
www.docuthek.com
Heat treatment systems in the metalworking industry · Edition 06.07
Kromschröder · 3
Strip galvanising plant
Electric-Furnace works photograph
Bogie hearth annealing furnace
Löcher works photograph
Heat treatment systems in
the metalworking industry
Furnace atmosphere/temperature distribution
Using Kromschröder impulse burners
with air/gas ratio control systems, it is
possible to achieve a homogeneous
temperature distribution throughout the
furnace atmosphere. Based on the efficient cross-current principle, our burners
ensure optimum mixing of gas and air.
Furnace atmosphere/lambda control
In many processes, maintaining a defined
furnace atmosphere is of great importance
in terms of the product quality. With technical know-how and an extensive product
range, we are a competent partner who
is able to develop system solutions for
staged or continuous lambda adjustment
or lambda control. The time-tested pneumatic ratio control system thereby ensures
that no dangerous excess gas occurs.
Hot air compensation
Flue gas temperatures must be kept as
low as possible if a firing system is to
work with a high level of efficiency. To
do so, the heat in the flue gas can be
returned to the process by directing it
through heat exchangers in order to raise
the temperature of the combustion air.
Elster Kromschröder can supply the necessary control valves for gas and air.
Burner line
Gas pressure
control line
Competence in gas
Owing to the use of the latest technologies, Elster Kromschröder can
offer you an innovative partnership in the metalworking industry.
We develop individual solutions in close
cooperation with our customers.
Automation systems
in switch boxes
Piping and wiring to
American Standard
4 · Kromschröder
Heat treatment systems in the metalworking industry · Edition 06.07
Shaft melting furnace
Striko/Westofen works photograph
Shaft melting and holding furnace
Marconi works photograph
Aluminium smelting furnace
Modulating control is the easiest and most
inexpensive way to control processes.
The capacity can be adjusted continuously by activating the air control valve
(analogue or 3-point step signal). The
pneumatic ratio control system controls
the gas pressure proportionally to the air
pressure and thus maintains a constant
air/gas ratio. At the same time, it acts as
an air deficiency cut-out. Adjusting valves
and/or butterfly valves are used for limiting
the air and gas volumes and for adjusting the air/gas ratio. In the example illustrated, the restrictor which is integrated
into the solenoid valve VAS is used in the
gas circuit for this purpose. Furnace pressure fluctuations have the same effect on
the gas and air throughput, so that the
air/gas ratio will remain unchanged.
Modulating-controlled heating
system with cold air and pneumatic ratio control system
Process control system
ϑ
M
Gas burner BIO/ZIO
Automatic burner control unit IFS/IFD
Ignition transformer TZI/TGI
Manual valve AKT
Air/gas ratio control VAG
Solenoid valve VAS
Bellows unit EKO
Motorised control valve BVA + IC 20
Bellows unit EKO
Cold air valve BVA
Ignition and monitoring is provided by
an automatic burner control unit which
must be approved for continuous operation if the burner is to operate for
more than 24 hours, in accordance
with EN 746-2. For burners over 350 kW,
pre-purge and setting the valve to ignition position must be ensured by an
additional valve control system.
Melting pot
Heat treatment systems in the metalworking industry · Edition 06.07
Heating furnace
Heimsoth works photograph
Age-hardening furnace
Inotherm works photograph
Heat treatment furnace
for steel with open
combustion chamber
Staged control with rotary impulse control
is an optimal solution for systems requiring a control range greater than 1:10. In
the case of cyclical control, the burner
is switched on and off or is controlled in
High/Low mode and the control of the
output supplied to the process is achieved
by means of a variable ratio of the operating time to the pause time. In this type of
control, the burner outlet pulse always
maintains full momentum and maximum
convection is obtained in the furnace
chamber, even with regulated heating. This
facilitates a good uniformity of temperature even at low process temperatures.
Stage-controlled heating system with cold
air and pneumatic ratio control system
Process control system
MPT
PF
Kromschröder · 5
M
Impulse burner BIC
19” module subrack BGT with
impulse system MPT and automatic burner control unit PF
Ignition transformer TZI/TGI
Main gas solenoid valve VAS
Manual valve AKT
Air/gas ratio control with
solenoid valve VAG
Bypass solenoid valve
VBY/VAS
Gas adjusting cock GEH
Bellows unit EKO
Butterfly valve for air BVHS + IC 40
Bellows unit EKO with
restricting orifice
Automatic burner control units with air
valve control allow pre-purge without
additional air valve control system as
well as cooling via the burners which is
controlled by the impulse system. Two
valve outputs on the automatic burner
control unit for separate activation of the
bypass valve and main valve ensure the
fail-safe limitation of the start fuel flow
rate in accordance with EN 746-2. The
air supply can also be controlled in 2
stages using intelligent air control valves,
so that a defined air/gas ratio prevails
in the burner in all operating states.
Heat treatment systems in the metalworking industry · Edition 06.07
Rotary table furnace
MAERZ-Gautschi works photograph
Roller hearth furnace
Andernach und Bleck works photograph
Indirectly heated heat
treatment furnace
In processes in which the material must
not come into contact with the combustion
gases or in inert gas furnaces, the heating
is performed indirectly with radiant tubes.
For optimal energy use, recuperative
burners firing into a single-ended radiant
tube or P radiant tube are often installed
for this purpose. The system is controlled
by a rotary impulse system with ON/OFF
operation of the burners. The burner pulse
ensures recirculation of the flue gases in
order to maintain a uniform radiant tube
temperature and to reduce NOx emissions.
Stage-controlled heating system with recuperative burner
Profibus
Process control system
Kromschröder · 6
Recuperative burner Ecomax
Burner control unit BCU 465 B1
Air flow pressure switch DG
Main gas solenoid valve VAS
Manual valve AKT
Gas solenoid valve VAS..L
Gas adjusting cock GEH
Bellows unit EKO
Air solenoid valve VR..N
Bellows unit EKO
Air adjusting cock LEH
The burner control unit BCU allows air
supply and/or air post ventilation and the
burners can be connected to the plant control system via PROFIBUS-DP. Where differential pressure switches are used for flow
monitoring, a pneumatic air/gas ratio control system is not required if defined supply
pressures are guaranteed and monitored.
7 · Kromschröder
Heat treatment systems in the metalworking industry · Edition 06.07
Car bottom forging furnace
MAERZ-Gautschi/Saarstahl works photograph
Bogie hearth forging furnace
Saarstahl works photograph
Steel forging furnace
with flat flame burners
Modern forging furnaces are equipped
with flat flame burners to avoid
the material coming into contact
with the flame and thus prevent local overheating of the material.
Stage-controlled heating system with hot air
Flat flame burner with ignition lance BIO..KBL
Burner control unit BCU 480
Main gas valve VAS
Manual valve AKT
Pressure regulator with solenoid valve VAD
Bypass valve VBY
Pilot gas pressure regulator GDJ
Air/gas ratio control GIK..B
Bellows unit EKO
Butterfly valve DKR..H
Solenoid-operated
butterfly valve BVHM
Restricting orifice
Bellows unit EKO
Pilot air pressure regulator
Pilot air pressure switch
Pilot air adjusting cock GEH
An ignition lance minimises the increase
in oxygen in the furnace atmosphere.
The burner control unit BCU or automatic burner control unit PFU ensures
independent monitoring of pilot and
main burners as prescribed by EN 746.
The different closing characteristics of
the butterfly valve for air and the gas
solenoid valve can be compensated
by setting a low fire over run time.
Air preheating via a central recuperator is state of the art and requires hot
air compensation in order to ensure a
constant air/gas ratio in the burner. This
can be provided by pneumatic ratio control systems (WPS) in the gas circuit or, in
the air circuit, by supply pressure control
or temperature-dependent opening of
the butterfly valve for air. Compensation in the air circuit offers the advantage
that the burner output remains constant
even at changing hot air temperatures.
However, this generally requires independent monitoring of the air/gas ratio.
8 · Kromschröder
Heat treatment systems in the metalworking industry · Edition 06.07
Aluminium tank furnace
Inotherm works photograph
Bell-type furnace
LOI Thermprocess works photograph
Important products
for your process
Controls series valVario®
The controls series valVario® can be
used for safety, control and the regulation of the air and gas supply systems
to gas appliances. It can also be used
for main gas control and safety.
Burners BIO, ZIO and BIC, ZIC
The burner capacities of these burner
series range between 1.5 and 5000 kW.
These burner series are characterised
by direct ignition and monitoring and
an optimised low pollution combustion
process. Thanks to their modular design,
customised variants for various applications and types of gas can be supplied.
The burners BIO and ZIO are equipped
with a heat-resistant flame tube to be
combined with a burner quarl. For applications in the lower and medium
temperature range, the burners can also
be operated with a refractory attachment tube instead of the burner quarl.
Burners of series BIC and ZIC are prepared
for attachment of a ceramic tube set TSC.
Ceramic tubes TSC
The TSC ceramic tube set range covers
all conceivable conditions of use. There
are different versions for various flame
shapes, capacities, flue-gas outlet velocities or application temperatures.
Flat flame burners BIO..K, ZIO..K
Tailored for use in forging furnaces where
maximum protection from thermal stresses
is afforded to the components. The flame
shape allows the heated material to be
positioned immediately in front of the
burner. The rapid supply of large quantities
of energy through the front of the flat flame
means that the flame temperatures can be
kept low. Rated capacity up to 1000 kW.
valVario® is suitable for a maximum inlet
pressure of 500 mbar. The space-saving,
compact design means that it is easy to
install. On the standard version, the flow
adjustment can be checked using an indicator, while a blue LED is used to check
the overall function. The device can also be
fitted with a position indicator with integral
visual indicator. Nominal sizes DN 10 to
125 with threaded or flanged connections.
Actuators IC 20, IC 20..E, IC 40
The actuators IC 20 and IC 40 are designed for applications that require
precise, controlled rotary movement between 0° and 90°. They can be mounted
directly onto the butterfly valves BVG,
BVA or BVH in order to control the gas
and air flow rates on gas burners.
IC 20 is controlled by a three-point step
signal. The automatic/manual mode
changeover and the position indicator that
can be read externally assist in the setting
of the infinitely adjustable switching cams
upon commissioning. IC 20-E can also be
controlled by analogue 0 to 10 V or 4 to
20 mA input signals. In addition, it provides
a feedback function and automatic setting of the analogue characteristic curve.
The electronic actuator IC 40 can be used
in continuously controlled burners and
in stage-controlled burners. Operating
characteristics and positions can be set
via parameters. The PC software BCSoft
can be used for programming as well as
reading the history memory and activating Manual mode for easier servicing.
Heat treatment systems in the metalworking industry · Edition 06.07
Kromschröder · 9
Drying furnace
Solar Impianti works photograph
Double-layer rotary hearth tempering furnace
IOB-Weinheim works photograph
Butterfly valves BVG, BVA, BVH
The butterfly valves BVG, BVA, BVH and
BVHS are designed to adjust volumes of
gas, cold and hot air and flue gas up to
450°C on various appliances and flue
gas lines. They are designed for control
ratios up to 1:10, and with the mounted
actuator IC 20 or IC 40 they are suitable
for regulating flow rates for modulating
or stage-controlled combustion processes. Max. inlet pressure 150 mbar.
Burner control units PFU + BCU
For directly ignited burners or pilot and
main burners in intermittent or continuous
operation. BCU/PFU..L with air valve control. Manual mode for burner adjustment.
The unit displays the operating status of
the burner module, the flame signal and
unit parameters. Automatic restart function and adjustable start-up attempts to
enhance the system availability. The unit
can be adapted to the specific application via an optical interface and the PC
diagnostic and programming software,
BCSoft for Windows. Comprehensive
analysis tools such as line recorder or
history memory facilitate commissioning and servicing of the heating system.
Butterfly valve BVHM with solenoid actuator M..B
Solenoid actuator M..B indicates the position of the valve disc. The air volumes
for low and high fire can be controlled independently. Due to the large
number of operating cycles of solenoid
actuator M..B, the butterfly valve BVHM
is suitable for intermittent operation.
Automatic burner control unit IFD
The IFD 400 series is designed for directly ignited burners in continuous
operation. It has a digital display for the
program status and flame signal and
is suitable for multi-flame control.
PFU
Automatic burner control unit for mounting in 19” module subracks. PFU 760
for directly ignited burners, PFU 780 for
pilot/main burners. Diverse customised
combinations thanks to an extensive
choice of supplementary components.
Every device with own power supply. Connection to Profibus-DP using
the field bus interface module PFA.
BCU
Automatic burner control unit, ignition
transformer and operation-control module in a compact metal housing take the
place of the local control cabinet. The
integrated operating and diagnostics unit
facilitates on-site commissioning and
servicing. Optional Profibus-DP field bus
interface. BCU 460 for directly ignited
burners, BCU 480 for pilot/main burners. BCU 465 with extended air control,
e.g. for operating radiant tube burners.
T +49 541 1214-0
F +49 541 1214-370
info@kromschroeder.com
www.elster.com
www.kromschroeder.com
Kromschröder, a product
brand of the Elster Group
Copyright © 2007 Elster Group
All rights reserved.
03250170 ivd 06.07 500
Elster Kromschröder GmbH
Postfach 2809 · 49018 Osnabrück
Strotheweg 1 · 49504 Lotte (Büren)
Germany