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Eliminate high energy costs through special energy savings algorithms, learn more about control strategies to aid return on investment and implement smart solutions for your business.

Understanding the technical nature of heat treatment processes brings wide ranging benefits to a solution. Have confidence in solutions that have been proven to maximize efficiency, productivity and ultimately your return on investment for applications including:

  • Vacuum furnaces
  • Sealed quench and other atmosphere controlled, batch and continuous furnaces
  • Pit furnaces
  • Specialist retort furnaces
  • Gas retort annealing furnaces
  • Creep test furnaces
  • Bell or tophat furnaces / Rotary hearth furnaces
  • Diffusion and Diffusion Bonding Furnaces
  • Laboratory applications
  • Energy Management Solutions


    • IF you face the challenges of energy savings, emissions control, regulatory compliance, data and data validation, and high productivity, THEN have your desired solution specified, engineered, programmed, wired, installed and commissioned by a global dedicated team of Heat Treatment experts. A team that has application expertise in all types of furnace control, shop floor automation, batch and continuous processes.

    Is regulatory compliance important to you? In both prescriptive quality systems such as the Aerospace Industry Nadcap (AS7102, AC7102, AMS2750 Rev D) or company quality manual processes such as the Automotive industry standard QS9000 and TS16949 - we have people to help you.
     

    Applications:
         Creep Testing Furnace
         Vacuum Furnace Process
              Dual Sensor Vacuum Furnace Control
              High Temperature Vacuum Furnace
         Sinter Plant

    Compliance:
         Audited Regulations for Heat Treatment
         NADCAP
         Working with Aerospace Standard AS7102
         Working with Aerospace Material Specification AMS2750D

    Literature:
         Heat Treatment Flyer HA028265 Issue 3 (16 pages)
         Heat Treatment Catalogue HA029337 Issue 1 (170 pages, 15M)


    Creep Testing Furnace
    To meet the demands of specific applications, steel and alloys are produced in a wide variety of material structure.

    In order to evaluate the suitability of individual batches of material for any particular application samples may undergo a number of destructive and non-destructive tests. Creep testing is one method of material evaluation which is widely used in the following markets:

  • Aerospace and Automotive
  • Iron and Steel raw materials
  • Ordnance
  • General Engineering


    • The “Creep Test” is performed on an alloy sample to determine material structure and evaluate its stress characteristics. In very simple terms, a sample is heated to a material dependent stable temperature between 300°C and 1200°C. A load is then applied to the sample to exert a longitudinal force on the grain structure of the alloy. The sample is maintained in this state for the period of the test or until the component ruptures. During the test, data is continuously monitored and recorded to qualify the stability of the temperatures, loading and sample extension. It is important to maintain tight control of the temperature across the entire sample with 0.2 degrees centigrade being typical for the sample uniformity tolerance. To achieve this many furnaces employ highly accurate control devices with three zones of heating. Tests may run for many months and occasionally years, it is important therefore that control systems are designed to accommodate power fail and abort strategies which will allow tests to be continued after unplanned interruptions.

    Large creep laboratories may have several hundred furnaces, carrying out simultaneous testing of samples. The results from the tests form part of the audit trail of data for eventual components and for convenience many users rely on communicating control systems to provide automation to the process of data management:

  • Isolated thermocouple inputs
  • Easy adjustment of Setpoint
  • Power fail and recovery routines
  • Long term process stability
  • Measurement of “creep” and detection of sample break
  • Digital communications and Data management solutions

    •  

  • In a typical Eurotherm multi loop solution the master loop controls the temperature at the centre of the sample with two slave loops controlling the top and bottom zones. User wiring is employed to ensure the working setpoint for the master loop is also used by the slave loops. Temperature is measured by thermocouples attached to the samples. Heating control is most often via a solid state relay.

    Creep (or strain), can be taken into the control system either via an analogue input from a suitable transducer or through master communications from other digitally communicating devices.

    The control system can also access digital inputs and outputs to detect sample rupture and to control and monitor load beam leveling.

    		•
    Vacuum Furnace Process
    Vacuum furnaces are widely used in heat treatment processes, and vary widely in capacity and size. Equipment has consistently been improved over the last 30 years such that vacuum processing has become a widely used application in the Aerospace and Automotive Industry. Vacuum is considered to be any pressure which is below atmospheric pressure and in industrial applications may be expressed as torr, microns or millibars.

    Typical ranges for furnaces
    Vacuum Range mBar
    Atmospheric (ambient)
    Rough to medium vacuum
    High vacuum     		10E+3
    10E+3 to 10E-3
    10E-3 to <10E-7

    Vacuum effects

    The effects of treating components in a vacuum are two fold:

    1. In the medium-high vacuum region the partial pressure of the residual air in the furnace particularly O -H O is significantly reduced and will provide an environment to process components with little or no surface oxidation. The reduction of residual Nitrogen (N ) is also beneficial for materials, which would otherwise form nitrides.

    2. Decomposition of existing oxides in the surface of components may occur depending on the temperature and material type.

    Mechanical equipment

    Vacuum furnaces take many different mechanical formats, designs include common components, such as:
  • Work piece chamber or multiple chambers usually with water-cooled jacket, loading and transfer mechanism
  • Heat shields made of graphite board or high temperature material
  • Furnace furniture constructed of graphite or other high temperature material
  • Heating element often Graphite or alternatively Molybdenum or high temperature material for temperatures above 1000°C
  • Vacuum pumping system
  • Partial pressure control
  • Optional fan assisted circulation systems for annealing processes
  • Quenching vessels and/or gas/fan quenching system
  • Cooling system
  • Control system


    • The cellular concept of vacuum processing is becoming more widespread with multi-cell layouts used to integrate heat treatment into shop floor production and manufacturing.

    A typical simple single chamber vessel furnace is shown in figure 1.



    Figure 1 Typical single chamber bottom loading vacuum furnace


    Control system

    Each part of the process cycle calls for specific control features.

    1. Furnace programmable controllers to accommodate sequencing and monitoring of digital actions and overall furnace interlocks.


    Figure 2a Pump startup sequence example


    2. Vacuum pump sequencing control system.

    The vacuum pumping cycle requires the control system to interface with multiple low, medium and high vacuum gauge types. The mechanical pumps and high vacuum vapor pump need to be sequenced in a controlled way to ensure that the furnace is properly evacuated without damage to the pumps or back streaming of oil into the work chamber. The sequence is processed by comparing the actual value of backing line or chamber pressure to series of pressure setpoints in the medium/ high vacuum range. The sequence may also include, pump rate efficiency timers, leak rate testing and out gassing algorithms as well as furnace process and heater interlocks.



    Figure 2b Chamber pump down flow chart/sequence example


    3. Heat treatment programming controllers

    Vacuum heat treatment cycles are often complex and require multiple stage profiles. These profiles are defined against material and component specifications and are usually maintained against controlled recipes.

    Temperature programming profiles are often carried out over multiple segments where accurate control needs to be maintained during both the black heat and radiant heat regions. The cycle will most often follow defined heating rates and dwell periods depending on the treatment process being carried out. Special control optimization routines to automatically deal with the variation in process gain for large size furnace loads and the black heat radiant boundary, can lead to improved cycle times and product quality.

    Since heat treatment is a scientific process it is important to ensure that the workload follows the defined profile and special mechanisms must be employed to eliminate overshoot and to provide work piece thermocouple tolerance and compliance.

    Partial Pressure may be controlled within the work chamber by adding a controlled flow of high purity inert gas. Since some materials have relatively high vapour pressures they will exhibit signs of surface evaporation at medium to high vacuum levels. The purpose of partial pressure control is to raise the pressure level of the work piece chamber to prevent this otherwise detrimental effect.

    The Cooling process either, vacuum or aided cooling and Gas-Gas/Fan quenching routines are common requirements.

    Most modern furnaces include highly efficient heat exchangers and rapid cooling fans to aid the cooling and quench process. Vessels are designed to operate at back fill pressures in excess of 10Bar and the sequence must provide control of this part of the cycle.

    Some furnace cycles also make use of back filling with inert gas or the use of circulation fans during the heating process this is to aid heat transfer below the radiant heat range. For cellular installations optional oil quench systems may be built into the design.

    A simple typical profile is shown in Figure 3.

    4. Electrical power control

    Vacuum Furnace heaters are made of Graphite, Molybdenum or occasionally other high temperature alloys, they usually operate at voltages lower than the available mains supply and are connected to the supply through a transformer or saturable reactor.

    The element material must not be exposed to an oxidizing atmosphere whilst it is at temperature and special pressure interlocks in the vacuum controller are employed to prevent this. Thyristor power controllers are used to give the best results when the heaters are coupled to the supply via a transformer.

    5. Interface with vacuum gauges

    Special consideration needs to be taken over the interface of the control system with various types of vacuum gauges which are available.

    Modern gauges tend to be of the wide range or active type where the output span is scaled to coincide with a defined logarithmic range of vacuum. Eurotherm control solutions employ standard input linearization to accommodate many industrial vacuum gauges and where new ones are used a simple technique is available to recalculate the linearization required.

    Typical active gauges are:

    Atmosphere to medium vacuum 10E0 to 10E-4; Pirani gauges; Thermocouple gauges; and Strain gauges

    Vacuums in the range 10E-2 to 10E-9, Ion gauges; and Inverted magnetron gauges.

    Wide or full range gauges employ more than one measuring technique but have a continuous output across the range 10E0 to 10E-9.


    Figure 3 Typical profile
    Dual Sensor Vacuum Furnace Control
    The characteristics of a vacuum furnace cause the chamber temperature to be 5 to 10 degrees hotter than the workpiece. This is called a thermal gradient or Delta Temperature (Delta T).

    Many metallurgists prefer to control their vacuum furnaces using a thermocouple placed next to, or into, the furnace workpiece. This however can cause undesirable effects such as excessive heater temperatures and overshoot of the desired setpoint.

    Furnace manufacturers often use a chamber thermocouple placed near the furnace heaters in order to get around these problems. The ideal solution is to use a controller that has two separate control loops, each with its own thermocouple input. One loop will use the chamber thermocouple that is located near the heaters and the other loop will use the workpiece thermocouple. The control loop with the lowest output demand will be used to control the furnace temperature.



    2604 Solution

    Reduces maximum heater temperatures, increases heater life.
    Guarantees that the workpiece follows the required setpoint profile.
    Optimizes startup and settling times.
    Automatic switching from workpiece control, to chamber temperature control as conditions require. Provides a method of controlling maximum delta T.
    The ability to change the maximum delta T as the controller progresses through its setpoint program.
    A simple effective method to control a furnace.


    For this application Eurotherm has implemented a control technique called override control. Override control consists of two control loops, each with it's own input and setpoint, but they share a common control output. The lowest output of the two loops is directed to the common output circuit.


    Figure 1 Simple Override Control

    Figure 1 shows a simple override controller. The main and override control outputs are fed to a low signal selector. The override setpoint is set to a value somewhere above the normal operating setpoint, but below any safety interlocks or unexpected values. There is one auto manual switch for both loops. In manual mode the control outputs of both loops track the actual output therefore ensuring bumpless transfer when auto is selected.

    Although the 2604 is multi-loop controller it needs only one control loop to implement override. Each loop is capable of being set-up as an override control loop. Two profiles can be used in the setpoint programmer, one to set the chamber setpoint and the other to set the workpiece setpoint. In this manner the setpoints and their relationship to each other can change as the process is being run.

    Alternatively, one of the profiles can set the workpiece setpoint and the other can be used to set the Delta T between the workpiece and the chamber.
    High Temperature Vacuum Furnace
    High temperature vacuum furnaces are used to manufacture silicon carbide tubes and rings, which are used in high quality bearings. Due to the high working temperature of up to 1675°C and the silicon atmosphere thermocouples can only last for a few cycles. As these thermocouples are made from Tungsten they are very expensive. To reduce the T/C wastage a pyrometer is used at higher temperatures. Normally T/C’s are used for temperatures up to 1200°C and pyrometers from 1100°C. This gives a 100°C switchover range between the T/C and the pyrometer. However, there can also be a requirement to use thermocouple control on the full cycle in certain processes which go above 1200°C.

    A 2604 single loop programmer is used utilising its Toolkit blocks. Three PV inputs are used. The thermocouple is connected in parallel to two inputs, with one input (IP1) ranged 0-2000°C and the other (IP2) ranged 0-1200°C.

    The Pyrometer input, which is a 4-20mA linear signal representing 1100°C to 2000°C is connected to the third PV input (IP3).


    Using “Toolkit Blocks” we calculate Analogue 1 using the switchover function between IN2 and IN3. The result (AOP1) is then used as an input Analogue 2, which dependent on the state of a digital input will connect either IN1 or AOP1 to the actual process variable.


    Figure 1 Simple Override Control

    Other features include:

    Alarms on PV1 at 1090°C to open the sight glass window for the Pyro, and at 1210°C to retract the T/C when using Pyrometer mode.

    A 0-10Vac retransmission of PV1 to a chart recorder.

    Digital inputs for run and reset.

    Sinter Plant
    The function of the Sinter Plant is to supply the blast furnaces with sinter, a combination of blended ores, fluxes and coke which is partially ‘cooked’ or sintered. In this form, the materials combine efficiently in the blast furnace and allow for more consistent and controllable iron manufacture. Figure 1 shows a simplified diagram of a sinter plant.

    Materials enter the sinter plant from storage bins. They are mixed in the correct proportions using weigh hoppers, one per storage bin, except for the return fines for which an impact meter is used instead. Weighing is continuous, as is the whole sintering process. The weighed materials pass along a conveyor to the mixing drum where water is added either manually or as a calculated percentage of the weight of material entering the drum.

    The moisture content of the coke is measured in the strand roll feed hopper and used to trim the secondary water flow rate. The mix permeability is also measured and used to modify the amount of water required.

    The mix material is fed onto the strand from the hopper by a roll feeder. The bed depth is set and kept constant by adjusting the cut-off plate which is fitted with probes to sense the depth of material and automatically vary the roll feeder speed. The quantity of material in the feed hopper itself is held constant by automatic adjustment of the feed rates from the individual raw material bins.


    In Figure 1 Simplified diagram of a sinter plant

    Sintering
    The raw mix is ignited by the ignition hood, which is fuelled by a mixture of coke oven gas, blast furnace gas and sometimes natural gas. The calorific value of the mixture and the set hood temperature are controlled. A separate control system is provided to maintain a fixed hood pressure by adjusting the windbox dampers immediately under the ignition hood.

    The sinter strand is a moving conveyor of hot sinter, which continues to ‘cook’ after leaving the hood, where air is pulled from the sinter by a strand draught fan.

    An important part of the sintering process is burn-through. This is where the sinter layer has completely burned through its section and is detected by temperature probes under the sinter bed. Burn through should be achieved but must not occur too soon after the ignition hood. The draught on the strand is maintained at a preset value by controlling the main fan louvers from pressure measurements in the wind main. This governs the point at which burn through occurs.

    Sinter handling

    After the end of the strand, the sinter passes through a spiked roll crusher and the hot screens to the rotating circular cooler. A number of fans are usually used for cooling, and the speed of the cooler is determined by:

  • Strand speed
  • Bed depth


    • The fines removed by the hot screens are conveyed to the return fines bin.

    After cooling, the sinter is passed into the discharge bunker. At this stage, the level is controlled by varying the outlet feed rate (usually vibros).

    The sinter then passes to the cold screening area, where it is passed through crushers and screens to produce particles in a specific size range. Sinter below the required size passes over a belt weigher and returns with the hot fines to the return fines bin.

    The difference between the weight of the cold fines, and the weight of the total fines produced, gives a measure of the hot fines. Any abnormal variation in the rate of production of hot or cold return fines indicates a possible plant fault.

    The following factors can affect the rate at which fines are produced:

  • Mix control
  • Particle size
  • Chemistry
  • Weight
  • Moisture content
  • Bed depth
  • Ignition hood temperature and pressure
  • Warm screens


    • Two important properties of sinter are basicity, which is controlled by the amount of limestone, and strength, which is controlled by coke content.

    The sinter is now suitable for use in the blast furnace. Conveyors transport the material to the blast furnace stock house, where it is added to other materials to form the blast furnace burden.

    Mixing drum moisture control
    The amount of primary water added is proportional to the weight of raw mix entering the mixing drum. This can be easily achieved using a Eurotherm Process Automation control module as shown in Figure 2.


    Figure 2 Mixing drum moisture control 

    The secondary water feed setpoint is frequently taken as a proportion of the raw mix belt weigher PV. For greater accuracy, the moisture meter reading is used to trim the material/water ratio. This corrects the water flow rate according to the measured moisture content of the raw mix.

    Cascade control is not always used but since the water flow loop responds faster than the moisture loop it does produce better results.

    Ignition hood temperature control

    Figure 3 depicts the implementation of ignition hood temperature control with options for the control ratio.


    Figure 3 Ignition hood temperature control

    With the fixed ratio air lead temperature control, the temperature demand provides a setpoint for the air flow. The fuel follows the air flow in a fixed ratio making this a fuel efficient method.

    On the other hand, with variable ratio air lead temperature control, the air flow is fixed and the hood temperature controller output (the heat demand signal) feeds the ratio setpoint trim input of the gas controller. This method is normally used when there is a readily available source of cheap fuel e.g. blast furnace gas.

    Ignition hood pressure control

    This is normally achieved by varying the setting of dampers in the windboxes under the ignition hood. A single loop PID controller is generally used to automatically maintain the pressure at a desired value.

    Calorific value control of ignition hood fuel gas

    Blast furnace gas and coke oven gas are used to fuel the ignition hood burners. The calorific value of the fuel is controlled to a consistent value by a separate control loop. If the strand stops, a digital signal forces the ignition hood into a ‘low fire state’ and holds it there until the strand re-starts.

    It is easier to keep the ignition hood temperature constant if the calorific value of the fuel is controlled to within pre-defined limits, about 4,000 - 6,000 kJ/m3. By mixing coke oven gas with blast furnace gas, this calorific value is achieved. Figure 4 shows the calorific value control strategy.


    Figure 4 Calorific value control of ignition hood fuel gas

    Burn-through point control

    Burn-through point should ideally occur near the end of the strand bed. It is controlled by altering the strand speed. A number of variables will affect the burn-through point, such as strand bed depth, water content and the quality of the sinter.

    The strand speed is either controlled manually, or by measuring the waste gas temperatures as an indication of the burn-through point. If it occurs too early, the average waste gas temperature rises. If it occurs too late, the waste gas temperature decreases and the strand speed is slowed to compensate.
     


    Figure 5 Burn-through point control

    Windbox temperatures can be used to improve the monitoring and are added as a setpoint bias. Figure 5 shows this in the control strategy.

    Main fan suction and waste gas over-temperature control

    The suction produced by the main fan is varied by louvers near the fan inlet, which are controlled by a fan suction controller. If the waste gas temperature increases above a safe working limit a selector switch allows the waste gas over-temperature controller to position the louvers.

    Cooler speed control

    After leaving the strand, the hot sinter is cooled on a rotary cooler.
    The speed of the rotary cooler is controlled to match the strand demand defined by the bed depth and the strand speed.


    Audited Regulations for Heat Treatment

    Do you want complete peace of mind in meeting regulatory requirements? Would enabling thermal process equipment accreditation through expert control and information management help your solution? We can help you with a wide range of products and services designed to meet the audit regulations for Heat Treatment.

    Regulations fall into two main categories and we can provide you with solutions to meet both requirements:

    • Accreditation quality systems such as the aerospace standard AS7102 (Nadcap) and AMS2750
    • Company quality manual processes such as the automotive industry standard QS9000 and TS16949

    Glass Solutions
    Nadcap (National Aerospace and Defense Contractors Accreditation Program):

  • AS7102 - Nadcap requirements for heat treating
  • AS7102/1 - Requirements for national aerospace and defense contractors accreditation brazing program
    • Publications are available from http://www.eurotherm-heattreatment.com/regulations/#

  • AMS2750D - Pyrometry
    • Specifications are SAE publications and are available from http://www.eurotherm-heattreatment.com/regulations/#

    Further information on working with Aerospace Standard AS7102 and Aerospace Material Specification AMS2750D.

    Further information on Nadcap.
        Technical response to AS7102a.
        Nadcap Heat Treating Task Group Pyrometry Guide.
        Instrumentation System Accuracy Tests (SATs)

    TS16949

    ISO/TS 16949:2002 is an ISO Technical Specification which aligns existing American (QS-9000), German (VDA6.1), French (EAQF) and Italian (AVSQ) automotive quality systems standards within the global automotive industry, with the aim of eliminating the need for multiple certifications to satisfy multiple customer requirements.

    Together with ISO 9001:2000, ISO/TS 16949:2002 specifies the quality system requirements for the design/development, production, installation and servicing of automotive related products. The standard is maintained by an international group of vehicle manufacturers plus national trade associations: The International Automotive Task Force (IATF).

    Publications are available from an abundance of web sites such as:
        http://www.eurotherm-heattreatment.com/regulations/#

    How can we help you meet these quality requirements?

  • Business focus on regulations for industrial process at all levels in Eurotherm
  • Global involvement with Heat Treatment industry bodies
  • High capability manufacturing and service quality systems
  • Full range of field test instrumentation, control, monitoring and recording instruments
  • Products and services designed to help you meet the requirements of AS7102 and AMS2750D
  • High performance products to meet requirements of System Accuracy Tests (SATs)
  • Compliance with demands for maintenance of electronic records and electronic signatures
  • World renown control to aid Temperature Uniformity Surveys (TUS)
  • Advice and support documentation to aid the understanding of specifications
    		•

    Working with Aerospace Standard AS7102

    General Quality Systems (AS7102 Section 3)

    Understanding the demands of working to quality systems is vital to meeting their demands along with a key business focus to deliver products, services and advice to support companies with Nadcap accreditation and those seeking future accreditation. Eurotherm Ltd operates a Management System in accordance with ISO9001 and the TickIT Guide to ensure and demonstrate the design, development and manufacture of products and services conform to their specified requirements. The organization intends to maintain its reputation as a
    supplier of high quality equipment and software and a provider of efficient engineering services throughout the lifetime of its products    .

    Comply

    Process Planning and Control (AS7102 Section 4)

  • Batch management routines
  • Systems for recipe management, recipe revision control and recording of recipe selected
  • Simultaneous recording of actual process and required process parameters
  • Support for automated record keeping and multiple archive backups
  • Embedded logging of furnace malfunctions and interruption events


    • Personnel (AS7102 Section 5)
  • Comprehensive product user manuals
  • Application guides for heat treatment equipment
  • Training services and advice


    • Material Handling and Protection (AS7102 Section 6)
  • Systems for shop floor automation
  • Systems for monitoring remote time temperature records for refrigeration and sub zero temperatures


    • Test and Inspection (AS7102 Section 7)
  • Ability to manually or electronically embed relevant client test results into tamperproof process data files


    • Furnace Control and Maintenance (AS7102 Section 8)
    AS7102 section 8 covers the requirements for Furnace Control and Maintenance.
    This is a key area of business for Eurotherm where we provide Aerospace manufacturers and suppliers services and support, particularly with respect to the following areas:
  • Records of heating cycles
  • Furnace diagnostics
  • Control of the heating environment
  • Control routines and records for quench systems
  • Pyrometry testing
  • Automated vacuum furnace leak rate and pump down routines


    • Supporting Documentation
  • A comprehensive response to AS7102
    		•

    Working with Aerospace Material Specification AMS2750D

    Control solutions to meet the widest range of Nadcap requirements covering instruments as defined in AMS2750D, classes A – E and across furnace classes 1 – 6. Solutions can either be made up from discrete products or integrated systems which include unique benefits for Aerospace and Automotive manufacturers and suppliers.

    Comply

    World Class Products for Control

  • Over 40 years' reputation for high quality control in the aerospace and automotive industry
  • High precision and high accuracy products, with long-term repeatability and performance
  • World renown control algorithms
  • High precision temperature and process profile programmers
  • Excellent for use in integrated temperature vacuum and atmosphere applications
  • In-built features to aid systems accuracy tests
  • Batch and recipe management
  • Multi-user password protection and complete audit trail systems
  • Support for furnace diagnostics and maintenance
  • Communication to work-piece tracking over-temperature protection


    • Features to aid calibration and instrument Systems Accuracy Test
  • All products covered by unique serial number and/or password protected Instrument tag
  • Thermocouple input conversion complies with ASTM230 or national standards
  • Routines to restrict thermocouple use outside authorized range
  • Routines to record control monitoring and work load thermocouple cycles and usage
  • Calibration of instrumentation to meet requirements as defined by AMS2750 in table 3 for:
  • Field test instruments
  • Control, monitoring or recording instruments
  • Chart recorders and data management solutions to meet the resolution and speed requirements of AMS2750D tables 4 & 5
  • Products designed for long-term calibration stability
  • Fully documented manufacturers procedures for recalibration and introduction of offsets
  • Procedures to meet accuracy requirements for:
  • Field test instrumentation
  • Controlling, monitoring and recording instruments
  • Password protected calibration and offsets
  • Digital communications of all parameters for easy recording of SATs and offsets
  • Digital instruments have readability to meet requirements of AMS2750D table 4 Note 2
  • Products meet the sensitivity requirements of AMS2750D table 3 Note 4
  • Error checking for digitally processed parameters used in control systems


    • Enhanced Features to aid Furnace Temperature Uniformity Performance
  • Specialist cutback overshoot parameters
  • Specialist overshoot techniques for ramp/dwell transitions
  • Alternative high stability control algorithms for gas and electric furnaces
  • Multiple tuning sets or dynamic tuning to aid TUS over wide range of setpoints and load sizes
  • Work thermocouple monitoring and control routines
    • Power feedback routines to eliminate impact of supply voltage changes on control stability Mathematical functions and graphical soft wired solutions Capability for continuous and sequential furnace control

    Support and Applications Knowledge
  • Provision of local accredited services and application knowledge
  • Furnace instrumentation system audits
  • Data management network service support
  • Furnace optimisation services
  • Regional onsite services for system accuracy tests to national accredited standards
  • Regional onsite services for Temperature Uniformity Survey tests
    		•