techno instruments temperature sensors, rtd, thermocouples technical guide
DESCRIPTION
Technical Guide - Temperature Sensors, RTD, ThermocouplesTRANSCRIPT
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Plot No 1145/1, Opp. Maruti Industries,Uma Convertor Lane, Near Vadi Char Rasta, Santej,Tal.: Kalol-382721, Dist.: Gandhinagar, Gujarat, India.
Ph.: +91 2764 268002/3/4, +91 9909925237 Fax: +91 2764 268109 E-mail: [email protected]
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Welcome NoteWith over hundreds of clients in almost all possible applications of Temperature Measurements in every industry like Power, Chemical, Process, Pharmaceutical, Cement, Metal etc. we have dedicated all our resources to deliver cost effective, reliable, and long-lasting solutions to our customers everywhere.
In our drive to become a internationally recognized service provider, we offer a complete gamut of all types of RTD and thermocouples suitable for measuring temperature of all types of furnaces, boilers, turbines and machineries under one roof.
To some of you, who are meeting us for the first time, we say "Thank you" for letting us make a first impression-One that we hope will convince you beyond any doubt that Techno can be your preferred make for RTD & Thermocouples along with complete solution to your related problems.
To those who already know us, we invite you to take a fresh look at who we are today. With a clear focus on Temperature Measurement, we are upgrading ourselves with most advanced technologies as a solution oriented company that makes decisions based on customer requirements and the latest market needs.
Abhijit Gohel
Director
Vision & Mission Statements
Quality Statement
Mission: "Growing from strength to strength, Techno Group is dedicated to improving the quality of Temperature Sensing Devices, making them better, safer, easier, and above all suitable to customer."
Vision: "To be established as one of the top solution providers for temperature measurements in the country by means of recognition well within and outside the Industry with constant technical & psychological development through continuous R&D.
It is the policy of Techno Instruments to maintain an effective Quality Program in order to provide products and services that meet and exceed our customers requirements in conformity with regulatory requirements, internationally recognized quality standards and industry accepted practices.
Our commitment to continuous improvement will insure achievement of our goals and objectives as reflected in our Mission Statement, Vision, and Core Values.
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resistancethermometers-rtdDue to the need of industry for greater accuracy and stability, the resistance thermometer (RTD) is becoming more widely used. The platinum RTD having a nominal resistance of 100 ohms at 0C and a temperature coefficient of 0.00385 is emerging as a world standard.
Common Resistance Materials for RTDs: Platinum (most popular and accurate), Nickel & Copper
Detector Tolerance and AccuracyThe RTD bulbs used in Techno assemblies conform to IEC 751-1983 and in standard form are supplied to class 'B' tolerance. Other tolerances of class 'A', 1/3 & 1/10 DIN are available on request. Also available are Nickel 100, 120 ohm and Platinum 46, 50, 100, 200, 500, 1000 ohms Cu 53, 2000 ohms.
RTD Terms RTD (Resistance Temperature Detector)
An acronym for resistance temperature detector or device. A resistance temperature detector operates on the principle of change in electrical resistance with respect to change in temperature.
RTD Element Sensing portion of the RTD which can be made most commonly of platinum, nickel, or copper. TECHNO features two styles of elements: wire wound and thin film.
RTD Probe An assembly composed of an element, a sheath, a lead wire, and a termination or connection. The standard TECHNO RTD probe is made with a 100 ohm platinum European curve element (alpha = 0.00385).
Platinum RTD Also known as PRTD, Platinum RTD's are typically the most linear, stable, repeatable, and accurate of all RTD's.
Thin Film RTD Thinfilm RTD's are made up of a thin layer of a base metal embedded into a ceramic substrate and trimmed to produce the desired resistance v a l u e . T E C H N O RTD's are made by depositing platinum as a film on a
substrate and then encapsulating both. This method allows for the production of small, fast response, accurate sensors. Thin film elements conform to the European curve/DIN 43760 standards.
Class A RTD For Class A sensor the following relationship applies where T is the absolute temperature:rT=(0.15+0.002 * t) For t =75 0C, the tolerance is therefore: rT=(0.15+0.002 * 75)=0.30C
Class B RTD For a Class B sensor the following relationship applies:rT= (0.3+0.005 * t). In the above example the deviation is therefore: rT= (0.3 + 0.005 * 75) = 0.675 0C
Wire Wound This elements are made of alpha grade platinum wire. Wire is wound on a mandrel to make coil and inseted In a ceramic tube and hermetically sealed within glass capsule.
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Choice of Sensor
There are many options to consider when choosing the correct RTD element for your requirements:
1. Temperature range
2. Tolerance, Accuracy
3. Time response
4. Vibrations
When to use Resistance Temperature Detectors
When accuracy and stability are a requirement of the customers Specification.
When accuracy must extend over a wide temperature range.
When area, rather than point sensing improves control.
Temperature rangeThe internal assembly construction falls into two temperature ranges:
Low 200C to +250C
High 200C to +600C.
Low temp- 3mm, 4.8mm, 6mm, 8mm, 9.5mm dia 316 SS tube alumina powder filled.High temp- 3mm, 6mm dia 316 SS metal sheathed mineral insulated/Ceramic beads insulated
Tolerance of PT 100 ( Alpha 0.003850 ) @ 0C
Class A : 0.15 C
Class B : 0.3 C
1/3 DIN : 0.10C
1/10 DIN : 0.03C
Features and Benefits of TECHNO make RTDs Accuracy: A special process combines strain-free construction with
partial winding support for accurate readings and long term stability in standard RTD elements.
Interchangeability: Strain-free construction and precision trimming allow elements from different lots to be substituted without recalibration.
Sensitivity: Self-heating is minimised, allowing precise measurement. The temperature coefficient (alpha) is carefully controlled at the industry standard while insulation resistance values exceed IEC-751 standards.
Standardisation: Elements are available to meet or exceed the requirements of various standardisation agencies. IEC- 751 standard tolerance classes A and B respectively are very well suited for industrial applications. Tolerance classes up to 1/10th DIN can also be supplied where higher accuracy is demanded
Physical and Chemical Stability: Over a wide temperature range is ensured by Techno's highly controlled manufacturing process. Standard elements are built to resist mechanical vibration and shock, however where there is high exposure to mechanical vibration, specially manufactured film RTD elements can be supplied to suit the application.
Repeatability: All elements exceed IEC-751 repeatability values even after long exposure to temperatures within the operating range.
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resistance thermometers-rtd
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Wire Wound Elements Wire wound elements are a hand made product which involves lot of skilled Labor. It is manufactured by placing a coil of thin wire (7 microns to
35 microns) into a ceramic insulator. The resistance of the coil is suitably adjusted to the ohms corresponding to that particular temperature. Ideally,
this coil should be freely suspended for natural expansion and contraction. However, such construction is not immune to vibration and hence it is
not adopted for industrial application. For industrial application, normally partially supported or fully supported construction is used which are
quite immune to vibration. The extended leads Are quite rugged as compared to the alpha wire and normally made from Pt base metal (for
Platinum resistors). The choice of ceramic insulator is also very important as any impurities in the insulator may detoriate the characteristic of the
alpha wire.
Thin Film PRTD
Good vibration resistance
Poor to thermal shock / cycling
Limited temperature range, we recommend ambient to 250 0 C
Poor repeatability
Small in dimension as small as (1.5mm X 1.5mm X1.2mm) ; (L X B X T)
Measuring current limitation to 1 mA. High self-heating.
Wire Wound PRTD
Moderate to poor vibration as per basic coil support
Moderate to good performance against thermal shocks
Vast temperature range -200 to 650 0 C
Quite long in size as compared to film type(15 mm minimum)
Measuring current as high as 10 mA can be used.
Good repeatability
The disadvantage of film type elements are1. The film is covered rigidly by glass layer and so the Platinum is not free to expand. The result is they can not maintain characteristics specially at
higher Temperature
2. The film contains very little metal and hence there are more chance of contamination from the impurities of the glass covering.
3. The unit have very little size and mass is also small. Hence they are subject to self heating error when sensing current is pass through it.
4. Control of homogenous of metal is difficult as compared to wire used in wire wound elements
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resistance thermometers-rtd
Lead Configuration & Color CodeThe resistance in the leads to the RTD (resistance temperature device) may significantly affect accuracy. To deal with this problem, connection arrangements are available which allow the lead resistance to be measured and compensated for, these are shown below:
Various constructions of RTD elements Film TechnologyThick film is produced by spreading Platinum paste through a silk screen onto a ceramic substrate. Thin film is produced by evaporation of metal onto a substrate and then by suitably itching with LASER technology. The basic advantages of both types are they are mass produced elements, they are cheaper as well as they can work in environment. Where extreme vibration is presence
Used where lead length is short. There is no compensation for resistance of lead wires.
Most common type of RTD assembly. Typically connected to standard bridge circuit, which allows lead wire resistance to be compensated.
Where higher accuracy is demanded. Lead wire resistance errors are eliminated in this configuration by measuring the voltage across the RTD element supplied with a constant current.
2 Wire
3 Wire
4 Wire
WHITE
RED
WHITE
REDRED
REDRED
WHITEWHITE
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resistance thermometers-rtd
Thermocouple or Resistance Temperature Detector
ADVANTAGES & DISADVANTAGES OF RTD & THERMOCOUPLES
Advantages of Thermocouples Inexpensive No resistance Lead wire Problems Fastest Response Simple and Rugged High Temperature Operation Tip (end) Temperature Sensing
Disadvantages of Thermocouples Least Sensitive Non-linear Low Voltage Least Stable, Repeatable
Advantages of Resistance Temperature Detectors Linear over wide operating range Wide temperature operating range Interchangeability over wide range Good long term/short term stability.
Disadvantages of Resistance Temperature Detectors Low sensitivity Higher cost than thermocouples No point sensing Affected by shock and vibration Requires three or four-wire operation
Summary Resistance Temperature Detector or Thermocouple: Both thermocouples and RTD's are useful sensors for determining process temperature. RTD's provide higher accuracy than thermocouples in their temperature range because platinum is a more stable material than are most thermocouple materials. RTD's also use standard instrumentation wire to connect to the measurement or control equipment.
Thermocouples are generally less expensive than RTD's, they are more durable in high vibration or mechanical shock applications and are usable to higher temperatures. Thermocouples can be made smaller in size than most RTD's so they can be formed to fit a particular application.
One to One AssessmentParameter/Criteria Thermocouple RTD
Typical Measurement - -267 C to -240 C to Range +2316 C +649 C
Interchangeability Good Excellent
Long-term Stability Poor to Fair Excellent
Accuracy Medium High
Repeatability Poor to Fair Excellent
Sensitivity (Output) Low Good
Parameter/Criteria Thermocouple RTD
Response Medium to Fast Fair
Linearity Fair Good
Self Heating No Low
Tip (end) Sensitivity Excellent Fair
Lead Effect High Medium
Size/Packaging Small to Large Medium to Small
SENSING ELEMENT MATERIALS AND TEMPERATURE LIMITSMaterial : Usable Temperature RangePlatinum : -200C To 850CNickel : -100C To 315CCopper : -75C To 150C
Technical Data for Resistance Temperature Detectors
PLATINUM RESISTANCE TEMPERATURE DETECTOR TOLERANCE VALUESTemperature Resistance Value Tolerance IEC-751 C Class A C ( ) Class B C ( )-200 18.49 0.55-(0.24) 1.3-(0.56)-100 60.25 0.35-(0.14) 0.8-(0.32)0 100.00 0.15-(0.06) 0.3-(0.12)100 138.50 0.35-(0.13) 0.8-(0.30)200 175.84 0.55-(0.20) 1.3-(0.48)300 212.02 0.75-(0.27) 1.8-(0.64)400 247.04 0.95-(0.33) 2.3-(0.79)500 280.90 1.15-(0.38) 2.8-(0.93)600 313.59 1.35-(0.43) 3.3-(1.06)650 329.51 1.45-(0.46) 3.6-(1.13)
CONNECTING WIRE TEMPERATURE LIMITS - CONSTRUCTIONWire / Insulation Materials : Maximum Usage TemperatureNickel Plated Copper/ PTFE Insulated : 250CSolid Nickel Wire : 650CSolid Copper Wire : 300C
CONNECTING WIRE TEMPERATURE LIMITS - EXTENSIONWire / Insulation Materials Maximum Usage Temperature Tinned Copper/PVC Insulated 105CSilver Plated Copper/ PTFE Insulated 205C Silver Plated Copper/ PTFE Insulated 250CNickel Plated Copper/ PTFE Insulated 250CNickel Plated Copper/Fiberglass Insulated 480C
Typical values of currents recommended for sensors for minimal self-heating are between 1mA and 5mA.
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A thermocouple is a sensor for measuring temperature. It consists of two dissimilar metals, joined together at one end. When the junction of the two metals is heated or cooled a voltage is produced that can be correlated back to the temperature. The thermocouple alloys are commonly available as wire.
A thermocouple is available in different combinations of metals. The four most common calibrations are J, K, T and E. There are high temperature calibrations R, S, and B. Each calibration has a different temperature range and environment, although the maximum temperature varies with the diameter of the wire used in the thermocouple. Although the thermocouple calibration dictates the temperature range, the maximum range is also limited by the diameter of the thermocouple wire. That is, a very thin thermocouple may not reach the full Temperature Range.
Because a thermocouple measures in wide temperature ranges and can be relatively rugged, thermocouples are very often used in industry. The following criteria are used in selecting a thermocouple:
What are the different thermocoupletypes?
How to select a thermocouple type
thermocouple
Temperature range
Chemical resistance of the thermocouple or sheath material Installation
requirements (may need to be compatible with existing equipment; existing holes may determine probe diameter)
Sheathed thermocouple probes are available with one of three junction types: grounded, ungrounded or exposed (see graphic below: ("Thermocouple Tip Styles"). At the tip of a grounded junction probe, the thermocouple wires are physically attached to the inside of the probe wall. This results in good heat transfer from the outside, through the probe wall to the thermocouple junction. In an ungrounded probe, the thermocouple junction is detached from the probe wall. Response time is slower than the grounded style, but the ungrounded offers electrical isolation the thermocouple in the exposed junction style protrudes out of the tip of the sheath and is exposed to the surrounding environment. This type offers the best response time, but is limited in use to dry, noncorrosive and nonpressurized applications.
How to select a junction type
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thermocouple
Thermocouple type letters listed above in parenthesis, while industry standard, are non-ANSI types.
** Type B voltage as a function of temperature is non-monotonic, with a minimum of -2.584972uV at a
temperature of 21.020262C. In consequence, function tcb_t() has a lower range limit of about -2.579382uV, at 22C.
T Copper Constantan -160C to +400C -5.6 to 17.82 mV
E Chromel Constantan -100C to +1000C -8.82 to 68.78 mV
J Iron Constantan 0C to +760C 0 to 42.28 mV
K Chromel Alumel 0C to +1370C -5.9 to 50.63 mV
R Pt-13% Rh Platinum 0C to +1000C 0 to 16.74 mV
B Pt30% Rhodium Pt 6% Rhodium 0C to +2000C -0.0258** to 13.82 mV
S Platinum/10% Rhodium Platinum 0C to +1750C 0 to 14.97 mV
(N) Nicrosil Nisil -270C to 1300C -4.34 to 47.50 mV
A N S ILetter
Thermocouple Joint Composition ThermocoupleTemperatureRange
EMF
Thermocouple's composition, temperature, and EMF properties.
positive (+) negative (-)
What is response time A time constant has been defined as the time required by a sensor to reach 63.2% of a step change in temperature under a specified set of conditions. Five time constants are required for the sensor to approach 100% of the step change value. An exposed junction thermocouple is the fastest responding. Also, the smaller the probe sheath diameter, the faster the response, but the maximum temperature may be lower. Be aware, however, that sometimes the probe sheath cannot withstand the full temperature range of the thermocouple type.
An exposed junction is recommended for the measurement of static or flowing non-corrosive gas temperatures where fast response time is required. The junction extends beyond the protective metallic sheath to give accurate fast response. The sheath insulation is sealed where the junction extends to prevent penetration of moisture or gas which could cause errors.
Type I (Grounded
Type II (Ungrounded)
Type III (Exposed)
A grounded junction is recommended for the measurement of static or flowing corrosive gas and liquid temperatures and for high-pressure applications. The junction of a grounded thermocouple is welded to the protective sheath, giving faster response than the ungrounded junction type.
An ungrounded junction is recommended for measurements in corrosive environments where it is desirable to have the thermocouple electronically isolated from and shielded by the sheath. The welded wire thermocouple is physically insulated from the thermocouple sheath by MgO powder (soft).
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thermocouple
Tolerances on Temperature Reading
1. IEC 584-2-1982 (Amendment 1 1989)
Classification of TolerancesClass 1 Class 2 Class 3
Type
Temp. Range ---Tolerance --- --- 4CTemp. Range --- Above 600C Below 1700C Above 800C Below 1700C
B Tolerance --- 0.0025 t 0.005 tPrevious Class --- --- Class 0.5
R Temp. Range Above 1100C Below 1600C Above 0C Below 600C Tolerance [1+0.003(t-1100)] 1.5C ---Temp. Range Above 0C Below 1100C Above 600C Below 1600C
S Tolerance 1C 0.0025t ---Previous Class --- Class 0.25 ---
Temp. Range Above -40C Below 375C Above -40C Below 333C Above -167C Below 40C N Tolerance 1.5C 2.5C 2.5C
Temp. Range Above 375C Below 1000C Above 333C Below 1200C Above -200C Below -167C
Tolerance 0.004t 0.0075t 0.015t
Temp. Range Above -40C Below 375C Above -40C Below 333C Above -167C Below 40CTolerance 1.5C 2.5C 2.5C
K Temp. Range Above 375C Below 1000C Above 333C Below 1200C Above -200C Below -167C
Tolerance 0.004t 0.0075t 0.015tPrevious Class Class 0.4 Class 0.75 Class 1.5
Temp. Range Above -40C Below 375C Above -40C Below 333C Above -167C Below 40C Tolerance 1.5C 2.5C 2.5C
E Temp. Range Above 375C Below 800C Above 333C Below 900C Above -200C Below -167C
Tolerance 0.004t 0.0075t 0.015tPrevious Class Class 0.4 Class 0.75 Class 1.5
Temp. Range Above -40C Below 375C Above -40C Below 333C Tolerance 1.5C 2.5C ---
J Temp. Range Above 375C Below 750C Above 333C Below 750C
Tolerance 0.004t 0.0075t ---Previous Class Class 0.4 Class 0.75 ---
Temp. Range Above -40C Below 125C Above -40C Below 133C Above -67C Below 40C Tolerance 0.5C 1C 1C
T Temp. Range Above 125C Below 350C Above 133C Below 350C Above -200C Below -67C
Tolerance 0.004t 0.0075t 0.015tPrevious Class Class 0.4 Class 0.75 Class 1.5
Above 600C Below 800C
Note:
1. Tolerance denotes the maximum allowable value obtained by subtracting the temperature reading or the temperature at the hot junction from the standard temperature converted from the applicable temperature EMF table.
2. Tolerance Class 1 for Type R and S only apply to the Standard or Reference thermocouple.
3. (t) denotes the value of temperature (C) irrespective of positive (+) or negative (-) sign.
4. Tolerances listed in this page a p p l y t o t h e n e w thermocouple wires.
Not standardized yet by JIS
Factors to ConsiderChoosing the correct thermocouple requires that you look at a number of factors. For example, a thermocouple, which is used only periodically, may be less expensive, but it may have a shorter life span and require servicing more often. If the thermocouple is intended to be used for long periods without service, it may be necessary to use a thicker gauge of wire and it may be necessary to use a design engineered for a greater degree of protection.
Below are some general guidelines to consider when choosing a thermocouple. If you need more help making a decision our knowledgeable sales staff is available to recommend a design which will best suit your application.
1.What are the maximum and minimum temperatures the thermocouple will see?
2.What error tolerances are necessary for you application?
3.What is the Measuring atmosphere? ( Corrosive / abrasive / vibrating etc)
4.What is the time response required?
5.Will the thermocouple be used continuously or periodically?
6.Will the thermocouple see bending or flexing during it's life?
7.What is the immersion depth?
General Guidelines
1.Do not allow excessive bending of the thermocouples. Cold working can lower the insulation resistance at certain points causing short circuits or decreased accuracy.
2.Use protection tubes for corrosive atmospheres .
3.Always inspect protection tubes when changing thermocouples. Things to look for include cracks, pinholes, contamination, or discoloration.
4.Do not locate the thermocouple too close to a heating element.
5.Record the life span and cause of failure for each thermocouple to help track down potential problems.
6.Never apply stress to platinum elements, they are fragile and will break easily at high temperatures.
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thermocouple
Operating and Maximum TemperatureLimits to Conductor Diameter (mm)
TYPE Wire Dia. Normal Operating Max. Temp.(mm) Temp. Range (C) Limit (C)
B 0.50 1,500 1,700R.S 0.50 1,400 1,600
0.65 850 9001.00 950 1,000
N 1.60 1,050 1,1002.30 1,100 1,1503.20 1,200 1,2500.65 650 8501.00 750 950
K 1.60 850 1,0502.30 900 1,1003.20 1,000 1,2000.65 450 5001.00 500 550
E 1.60 550 5002.30 600 7503.20 700 8000.65 400 5001.00 450 550
J 1.60 500 6502.30 550 7503.20 600 7500.32 200 250
T 0.65 200 2501.00 250 3001.60 300 350
Tolerance on Temperature Reading To ASTM E 230-2003
B Above 870C Below 1700C 0.5% 0.25%
R.S Above 0C Below 1480C 1.5C or 0.25% 0.6C or 0.1%
N Above 0C Below 1260C 2.2C or 0.75% 1.1C or 0.4%
K Above -200C Below 0C 2.2C or 2% -
Above 0C Below 1260C 2.2C or 0.75% 1.1C or 0.4%
E Above -200C Below 0C 1.7C or 1% -
Above 0C Below 870C 1.7C or 0.5% 1.0C or 0.4%
J Above 0C Below 760C 2.2C or 0.75% 1.1C or 0.4%
T Above -200C Below 0C 1.0C or 1.5% -
Above 0C Below 370C 1.0C or 0.75% 0.5C or 0.4%
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Thermocouples are widely used for temperature measurements of various gases and liquids. If bare thermo-element wires are exposed directly to detrimental atmospheres and fluid, they are often physically and chemically affected resulting in reducing service life with severe deterioration and corrosion. Thermocouples are, therefore, usually protected with insulators and protection tubes. In selection of suitable insulators and protection tubes, consideration should be given to the materials especially of heat resistance, mechanical strength, chemical stability, etc. depending on the respective operating conditions. This is the most important point in thermometric practice
thermowellmaterial selection
Material Operating Temp (C) Features
SS400 Oxi. 600 Red. 800 Good resistance to reducing atmosphere but less resistant to oxidation and acids attacks. Thick walled tubes are used in molten aluminum.
304 S.S. 980 Widely used as a common protection tube against heat and corrosion but not recommended for use in the presence of sulphur or reducing flame. Subject to stress and pit corrosion.
304L S.S. 980 Less carbon content (C=0.03%) than 304 S.S. and better resistance to grain boundary corrosion. Subject to stress and pit corrosion.
321 S.S. 980 Higher corrosion resistance than 304 S.S. because of its Ti content to prevent carbon preticiopation. Excellent resistance to grain boundary corrosion after welding due to less carbon preticipation.
316 S.S. 980 Contains Mo and has excellent resistance to corrosives, heat, acids and alkalis.
316L S.S. 980 Less carbon content than 316 S.S. and has beeter resistance to grain boundary corrosion, Resistant pit corrosion.
310S S.S. 1,000 High Ni-Cr content and good high temperature strength with resistance to oxidation at high temperatures. High mechanical strength.
347 S.S. 980 Because of its Nb-Ta content, prevents carbon preticipation. Higher corrosion resistance than 304 S.S. and excellent resistance to grain boundary corrosion.
446 S.S. 980 Excellent resistance to oxidizing and reducing flames. Containing sulphur. Suitable for use in non-ferrous molten metals and other high temperature applications, but less mechanical strength.
253 MA 1,000 Superior oxidation resistance to 310 S.S. at high temperatures due to formation of dense and tight oxide layer by silicon and cerium additions.Can be used under sulphurous atmospheres.
50Co-30Cr Oxi. 1,150 Red.1,200 Excellent resistance to heat, corrosion and abrasion. One of the best alloy against high temperature sulphur bearing atmospheres.
Inconel 600 1,050 Excellent resistance to oxidizing and reducing atmospheres at high temperatures. But sulphurous atmospheres should be avoided. Immune to stress and pit corrosion.
Inconel 601 1,050 Superior oxidation resistance at high temperatures to Inconel-600 by virture of strong bonding of metal oxide film.
Inconel 625 1,050 Improved strength and stress rupture properties up to 980C by Mo and Cb additions, and immune to chloride stress corrosion cracking.
Incoloy 800 870 Excellent to high temperature oxidizing atmospheres and thermal shock. About 10 times longer service life than 304 S.S. against high temperature corrosion.
Kanthal A1 1,100 Good resistance to high temperature oxidation but becomes brittle due to recrystallization. Poor mechanical strength above 850C.
Metal Protection Tubes
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thermowell material selection
80Ni 20Cr 1,100 Good mechanical strength and corrosion resistance at high temperature oxidizing atmospheres but not recommended for use in suphurizing atmospheres.
Hastalloy B Oxi. 500 Red. 760 Excellent resistance to heat and corrosion, especially to HCl and H2SO4.
Hastalloy C 276
Hasteallcy X 1,100 Excellent resistance to oxidizing and carburizing atmospheres at high temperatures. Better machin ability and weld ability than other Hastelloy alloys.
Titanium Oxi. 250 Red. 1,000 Superior corrosion rsitance in cryogenic temperatures but at high temperatures easily oxidized and becomes brittle.
Monel Oxi. 500 Red. 600 Excellent resistance to water vapor and sea water at high pressure and corrosion.
Tantalum Oxi. 300 Red. 2,200 Excellent heat-resistant material with high resistance to all acids apt to severe oxidation and embrittlement in air at high temperature.
1,000 Excellent resistance to high temperature oxidizing and reducing atmospheres and also to Cl4 gases.
Caution: Due to high thermal conductivity of the metal tubes, minimum insertion length should be more than twenty five times of its overall diameter to eliminate heat conduction error.
Note: Operating and maximum temperatures of the above tubes vary depending on the measuring environments. Special protection tubes such as Inconel-750, Kanthal other alloy tubes, etc. are also available upon request. Stainless steels as listed above table are in conformity with JIS Specifications and equivalent to those of AISI,U.S.A.
Material Operating Temp (C) Features
Quartz 1,000 99.99% QuartzExcellent to thermal shock but tragile. Poor resistance to alkalis but good to acides. Less gas-tightness in hydrogen and reducing gases. High thermal conductivity.
Silimanite 1,400 High Alumina ceramic, Good resistance to thermal Shock. Recommended for use in coal or oil burning and electric furnaces, Slightly porous.
Mullite 1,500 60% Aumina-40%SilicaSintered alumina. Better than PT2 but slightly less thermal shock resistance. Recommended for use in heating furnace and regenerator, impervious.
Recrystallized 1,600 99.5% AluminaAlumina Superior chemical stability and better than PT1. Recommended for use in molten steel, slag and molten glass
impervious.
Self-bounded 1,650 99%SiCSilicon Carbide Very low porosity, Execellent resistance to thermal shock, corrosion and abrasion at high temperatures Recommended
for use in oxidizing and reducing atmospheres up to 1,650C but attacked by water vapour.
Grade 530 1,050 Alumineous refractoryExtensively porous suggested for forging industries and applications exposed to thermal cycling.
Silicon Nitride 1,350 Excellent thermal shock resistance. Less corrosion to acids and alkalls. High hardness. Fairly good resistance against (SiaNi) most of molten metals.
Metal Protection Tubes
Caution:
1. Operating and maximum temperatures vary depending on the heat pattern and atmosphere. For low thermal conductivity ceramictubes, preheating and slow insertion into the furnace are recommended. Generally, insertion speed of 100 to 150mm per minute after preheating around 80 100C will be adequate.
2. Minimum insertion length of the non-metallic should be more than fifteen times of its overall diameter, excepting those of higher heat conductivity materials like SiC and Cermet, which need twenty five times or more.
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thermowell material selection
Application Protecting Tube Material
Bridgewall Types 304, 310, 316, 321,
347 SS, carbon steel
Power
Coal-air mixtures 304 SS
Flue gases Black steel, Type 446 SS
Pre-heaters Black steel, Type 446 SS
Steel lines Types 347 or 316 SS
Water lines Low carbon steels
Boiler tubes Types 304, 309, or 31 0 SS
Gas producers
Producer gas Type 446 SS
Water gas
Carburetor Inconel 600, Type 446 SS
Superheater Inconel 600, Type 446 SS
Tar stills Low carbon steels
Incinerators
Up to 1093C Inconel 600, Type 446 SS
Over 1093C Ceramic (primary)
Hexoloy (secondary)*
Food
Baking Ovens Slack Steel
Charretort, Sugar Slack Steel
Vegetables and fruit Type 304 SS
Application Protecting Tube Material
All concentration 100C Types 316 SS, Monel
Ammonium nitrate
All concentration - Type 316 SS
21 to 100C
Ammonium sulphate,
10% to saturated 100C Type 316 SS
Barium chloride,
all concentration 21C Monel, Hastelloy C
Barium hydroxide,
all concentration,21C Low carbon steels
Barium sulphite Nichrome Hastelloy C
Brines Monel
Bromine Tantalum, Monel
Butadiene Type 304 SS
Butane Type 304 SS
Butylacetate Monel
Butyl alcohol Type 304 SS
Calcium chlorate, Type 304 SS
dilute 21 to 66C
Calcium hydroxide
10 to 20%, 100C Type 304 SS, Hastelloy C
50%, 100C Type 316 SS, Hastelloy C
Carbolic acid, all, 100C Type 316 SS
Carbon dioxide, wet or dry 2017-T4 aluminum,
Monel, nickel
Chlorine gas
Dry, 21C Type 316 SS, Monel
Moist, -7 to 100C Hastelloy C
Chromic acid, Type 316 SS, Hastelloy C
10 to 50% 100C (all concentrations)
Citric acid
15%, 21C Type 304 SS, Hastelloy C
(all concentrations)
15%, 100C Type 316 SS, Hastelloy C
(all concentrations)
Chemical
Acetic acid
10 to 50%, 21C Type 304,
Hastelloy C, Monel
50%, 100C Type 316,
Hastelloy C, Monel
99% 21 to 100C Type 430,
Hastelloy C, Monel
Alcohol, ethyl, methyl
21 to 100C Type 304
Ammonia Types 304, 316 SS
All concentration 21C
Ammonium chloride
Heat Treating
'1 Annealin
Up to 704C Black stee
Over 704C Inconel 600, Type 446 SS
Carburising hardening
Up to 816C Black steel, Type 446 SS
816 to 1093C) Inconel 600, Type 446 SS
Over 1093C Ceramic*
Nitriding salt baths Type 446 SS
Cyanide Nickel (CP)
Neutral Type 446 SS
High speed Ceramic*
Iron and steel
Blast furnaces Incone 600,Type 446 SS
Downcomer Silicon carbide, LT-1
Stove dome Inconel 600
Hot blast main Inconel 600
Stove trunk Black stee
Stove outlet flue
Open hearth Inconel 600, Type 446 SS
Flues and stack Inconel 600, LT-1
Checkers Inconel 600, Type 446 SS
Waste heat boiler
Billet heating slab heating
and butt welding Inconel 600, Type 446 SS
Up to 1093C Silicon carbide, ceramic*
Over 1093C
Bright annealing batch Not required (use bare
Type J thermocouple)
Top work temperature Type 446 SS
Bottom work temperature Inconel 600, ceramic*
Continuous furnace section Silicon carbide, ceramic*
Forging
Soaking pits Inconel 600
Up to 1093C Silicon carbide, ceramic*
Over 1093C
Application Protecting Tube Material Application Protecting Tube Material
Nonferrous metals
Aluminum - Melting Hexoloy, Syalon,
1100, Cast, Iron
- Heat Treating Black steel
Brass or bronze Not required (use dip-
type thermocouple)
Lead Type 446 SS, black steel
Magnesium Black steel, cast iron
Tin Extra heavy carbon steel
Zinc Extra heavy carbon steel
Pickling tanks Chemical lead
Cement
Exit flues Inconel 600, Type 446 SS
Kilns, heating zone Inconel 600
Ceramic
Kiln Ceramic,
and silicon carbide
Dryers Silicon carbide,
black steel
Vitreous enamelling Inconel 600, Type 446 SS
Paper
Digesters Type 316 SS, Type 446S
Glass
Fore hearths and feeders Platinum thimble
Lehrs Black steel
Tanks Roof and wall Ceramic
-Flues and checkers Inconel 600, Type 446 SS
PetroleumDe-waxing Types 304, 310, 316, 321
347 SS, carbon steel
Towers Types 304, 310, 316, 321,
347 SS, carbon steel
Transfer lines Types 304, 310, 316, 321,
347 SS, carbon steel
Factioning column Types 304, 310, 316, 321,
347 SS, carbon steel
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thermowell material selection
Application Protecting Tube Material Application Protecting Tube Material
Saturated, 21 to 100C Type 316 SS, Monel
Sodium fluoride, 5%, 21C Monel
Sodium hydroxide Types 304 S, 316 SS,
Hastelloy C
Sodium hypochlorite, 5% still Type 316 SS, Hastelloy C
Sodium nitrate, fused Type 316 SS
Sodium peroxide Type 304 SS
Sodium sulphate, 21C Types 304 SS, 316 SS
Sodium sulphide, 21C Type 316 SS
Phosphoric acid
1%, 5%, 21C Type 304 SS,
10%, 21C Type 316 SS
10%, 100C Hastelloy C
30%, 21 to 100C Hastelloy B
85%, 21 to 100C Hastelloy B
Picric acid, 21C Type 304 SS
Potassium bromide, 21C Type 316 SS
Potassium carbonate, Types 304 SS, 316 SS
1%, 21C
Potassium chlorate, 21C Type 304 SS
Potassium hydroxide
5% 21C Type 304 SS
25% 100C Type 304 SS
60% 100C Type 316 SS
Potassium nitrate
5%, 21C Type 304 SS
5%, 100C Type 304 SS
Potassium permanganate, Type 304 SS
5%, 21C
Potassium sulphate, 5%, 21C Types 304 SS, 316 SS
Potassium sulphide, 21C Types 304 SS, 316 SS
Propane Type 304 SS,
low carbon steel
Pyrogallic acid Type 304 SS
Quinine bisulphate, dry Type 316 SS
Quinine sulphate, dry Type 304 SS
Seawater Monel, Hastelloy C
Salicylic acid Nickel
Sodium bicarbonate
All concentration, 21C Type 304 SS
5%, 66C Types 304 SS, 316 SS
Sodium carbonate,
5%, 21 to 66C Types 304 SS, 316 SS
Sodium chloride
5%, 21 to 66C Type 316 SS
Sodium sulphite, 30%, 66C Type 304 SS
Sulphur dioxide
Moist gas, 21C Type 316 SS
Gas, 302C Types 304 SS, 316 SS
Sulphur
Dry molten Type 304 SS
Wet Type 316 SS
Sulphuric acid
5%, 21 to 100C Hastelloy B, 316 SS
10%, 21 to 100C Hastelloy B
50%, 21 to 100C Hastelloy B
90%, 21C Hastelloy B
90% 100C Hastelloy D
Tannic acid 21C Type 304 SS, Hastelloy B
Tartaric acid
21C Type 304 SS
150C Type 316 SS
Toluene 2017-T4 aluminium,
low carbon steel
Turpentine Types 304 SS 316 SS
Whiskey and wine Type 304 SS, nickel
Xylene Copper
Zinc chloride Monel
Zinc sulphate
5% 21C Types 304 SS, 316 SS
Saturated 21C Types 304 SS, 316 SS
25% 100C Types 304 SS, 316 SS
Concentrated, 100C Type 316 SS, Hastelloy C
(all concentrations)
Copper nitrate Types 304 SS, 316 SS
Copper sulphate Types 304 SS, 316 SS
Cresols Type 304 SS
Cyanogen gas Type 304 SS
Dow therm Low carbon steels
Ether Type 304 SS
Ethyl acetate Monel, Type 304 SS
Ethyl chloride, 21C Type 304 SS
low carbon steel
Ethyl sulphate, 21C Monel
Ferric chloride, Tantalum, Hastelloy C
5%, 21C to boiling
Ferric sulphate, 5%, 21C Type 304 SS
Ferrous sulphate, dilute, 21C Type 304 SS
Application Protecting Tube Material Application Protecting Tube Material
Formaldehyde Types 304 SS, 316 SS
Formic acid, 5%, 21 to 66C Type 316 SS
Freon Monel
Gallic acid, 5%,21 to 66C Monel
Gasoline, 21C Type 304 SS
low carbon steel
Glucose, 21C Type 304 SS
Glycerine, 21C Type 304 SS
Glycerol Type 304 SS
Hydrobromic acid, Hastelloy B
98%, 100C
Hydrochloric acid
1%, 5% 21C Hastelloy C
1%, 5% 100C Hastelloy B
25%, 21 to 100C Hastelloy B
Hydrofluoric acid, Hastelloy C, Monel
60%, 100C
Hydrogen peroxide, Types 316 SS, 304 SS
21 to 100C
Hydrogen sulphide, Type 316 SS
wet and dry
Iodine, 21C Tantalum
Lactic acid
5%, 21C Type 304 SS, 316 SS
5%, 66C Type 316 SS
10%, 100C Tantalum
Magnesium chloride
5%, 21C Nickel,Monel,
5%, 100C Nickel
Magnesium sulphate,
hot and cold Monel
Muriatic acid, 21C Tantalum
Naptha, 21C Type 304 SS
Natural gas, 21C Types 304 SS,
316 SS, 317 SS
Nickel chloride, 21C Type 304 SS
Nickel sulphate, Type 304 SS
hot and cold
Nitric acid
5%, 21C Types 304 SS, 316 SS
20% 21C Types 304 SS, 316 SS
50% 21C Types 304 SS, 316 SS
50% 100C Types 304 SS, 316 SS
65% 100C Type 316 SS
Concentrated, 21C Types 304 SS, 316 SS
Concentrated, 100C Tantalum
Nitrobenzene, 21C Type 304 SS
Oleic acid, 21C Type 316 SS
Oleum, 21C Type 316 SS
Oxalic acid
5% hot and cold Type 304 SS
10%, 100C Monel
Oxygen 21C Steel
Palmitic acid Type 316 SS
Pentane Type 340 SS
Phenol
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ThermowellsThermowells which are made of solid bar stock of various heat and corrosion resistant alloys by drilling are usually preferred over the tip welded protection tubes for critical applications where high mechanical strength and longer service life are required. If the alloy bar material is correctly selected and designed properly, the Thermowell lasts long against corrosives, high pressure, high temperature, mechanical shock and vibration that may result from high velocity of fluids. In order to offer the best and safest. A specially developed computer programme as based upon operating conditions at the site makes Thermowells against Karmans Turbulence and other stresses, automatic calculations of mechanical strength to fluid pressure and flow velocity to estimate frequency of critical resonance. At TECHNO, a genuine Two Shaft Gun Drilling Machine of two-metre max manufactures Thermowells.
Thermowells are ideal where a sensor is required to be inserted into a process where external elements such as pressure, corrosion, or abrasion affect the life of the sensor. . Techno has been manufacturing solid barstock type Thermowells to accommodate applications in the petrochemical, chemical, refining, power and other process industries for many years. Threaded, flanged, weld-in, socket, Van Stone and other styles are custom made to your specs or available from our large inventory for immediate shipment. Optional coatings and sprays are also offered.
protection tubes& thermowells
Thermowell Design FactorsMaterial of Construction Thermowell material must be chemically compatible with the process system and the temperature sensor. In most cases, thermowell selection is based on the corrosive conditions in the well environment. Sometimes The selection may be based solely on the mechanical strength needed to withstand operating pressure and process flow. Often a combination of factors must be considered. In addition to selecting the proper base material, coatings may be used to improve a thermowell's resistance to abrasion or the chemical process.
The thermowell wall must be thin enough to minimize sensor error caused by thermal conduction and slow sensor response, but thick enough to withstand collapse from process pressure, erosion from abrasive media and bending from the process flow. Spring-load mounting styles are recommended to ensure positive contact to maximize thermal transfer and minimize sensor vibration within a thermowell.
Insertion Length The insertion length or 'U' length is the distance from the end of the well to the underside of the thermowell thread or other connection device. For maximum accuracy, this length must be long enough to permit the temperature sensor to be fully immersed in the media to be measured and minimize sensor error caused by thermal conduction, But short enough to withstand damage caused by process flow vibration. As a general rule of thumb, the thermowell should extend into the process a minimum of 10 times the sensor diameter or, in the case of RTDs, 10 times the sensor diameter plus one inch. This should extend the sensor into the process between 1/3 and 1/2 the diameter of the process pipe. The insertion length must also take into consideration any dead length required to pass through walls, pipe fittings and insulation.
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protection tubes & thermowells
Velocity The most common cause of well failure is the vibration effect caused by fluid forming a turbulent wake as it flows past the well. This turbulence has a definite vibration frequency based on the diameter of the well and the velocity of the fluid. The well must have sufficient stiffness to ensure that the wake frequency will never equal the natural frequency of the well. If the natural frequency of the well coincides with the wake frequency, the well will potentially vibrate to destruction. To be in compliance with the ASME Performance Test Code, the thermowell should have a natural frequency a minimum of 125% of the wake frequency. Tapered shank wells (heavy duty - Type H) have a high strength-to-weight ratio with a resultant higher natural resonant frequency than the equivalent length straight shank well. Tapered shank wells are preferred for operation at higher fluid velocities.
Process ConnectionTechno Instruments Technologies provides standardized wells in most of the common connection types, including threaded, flanged and socket weld types with standard bore sizes. Threaded wells are available in materials that can be readily welded. Flanged wells are manufactured by welding a bar stock well to the specified flange style. Doubled-welded construction reduces crevice corrosion and stress problems by ensuring that no open joints are exposed inside or outside the installation.
Bore Size Selection of a standard bore size throughout the plant permits the use of several types of temperature measuring instruments in the same wells. Techno standard bore sizes fit most bores. This number represents the inside diameter of the well, expressed in thousandths of an inch.
Standard Bores and Depths
Standard Sizes of Solid Bar Materials
Test and Inspections
Bore Dia. (mm) 4.0 5.5 7.0 8.5 10.0 11.0 12.0 16.0
Max. Depth (mm) 500 700 800 1200 1200 1200 1200 1200Commonly used temperature sensing devices.
Round Bars (OD in mm) Hexagonal Bars (width across flats mm)
25, 26, 28, 30, 32, 34, 36, 38, 40, 46, 48, 50 & 55 26, 29, 32, 35, 38, 41, 48, 50 & 55.Most applications use 0.260" or 0.385" diameter
Pressure Test : N2 gas pressure test up to 40 kg/cm is conducted upon request
Hydrostatic Pressure Test : Internal pressure test up to 600 kg/cmMPa is conducted upon request.
X-Ray Inspection : X-ray inspection for uniformity in wall thickness, eccentricity of bore and smooth inner finish are also conducted upon request.
Optional: Helium leak Test Dye penetrant Test Wake frequency calculation PMI
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protection tubes & thermowells
Protective coatings For some applications, thermowell resistance to environments can be greatly improved with surface applied coatings. Thus, a thermowell exposed to abrasion may be provided with a hard surface by applying suitable alloy coatings to the outside. While hardness levels tend to fall off with increasing temperature, some of these coatings remain quite hard (e.g. Rockwell C45) up to at least 1000 Deg F.
Techno is market leader in such coated Thermowells and had provided hundreds of its clients with positive drift in their cost-efficiency curve with the help of such protective coatings
Coating is applied over thestepped dwon base mental,which offers resistance toerosion as well as corrosion
Base metal is stepped downto allow coting application.
Typical Applications
Available Coatings
Cement Plants Outlet DuctsRefineries Chemical Reactors
High Speed Mixtures Boiler Beds
Coal mills
Tungsten-Carbide (Co-matrix) Teflon type
Aluminum Oxide Rubber Coatings
Zirconium Oxide Hastalloy Sleeves
Monel Sleeve Boron carbides
Titanium Sleeve Tantalum Sleeve
FEP Sleeve Glass lining
Titanium-Oxide Nickel Sleeve
Coating
Chromium carbide Others.
Tungsten Carbide deposited with HVOF for protection against erosion up to 500C.
Teflon coated thermowell
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Thermowell for coal mill
Thermowell for bed temperature of CFBC boiler
Slot type RTD formotor / generator winding temperature
Slot type RTD formotor / generator winding temperature
MTM Thermocouple for fossil Boiler tube skin temperature Turbine Supervisory Thermocouple
Hard faced T/W for protection against erisiomnat elevated temperature in economizer intel / aph intel
Thermocouple for gas turbinewheel space / bearing / exhaust
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application specific products for power industry
power industry
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application specific products for metal industry
Thermocouple for blast furnaceTitanium RTD for hard chrome plating bath
Thermocouple for SMS
Thermocouple for gas carburising / salt bath
Thermocouple for hot deep galvanizing / molten alluminium
Thermocouple for bake oven
metal industry
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application specific products for cement industry
Preheater / precalciner Tower Thermocouple Hard free thermocouplefor kiln / TA duct & secondary air
RTD for coal classifier RTD for grinding mills
Coller grare Thermocouple Bearing RTD
cement industry
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application specific products for chemical industry
RTD for Gas ChromatographRTD for Oxygen analyzerfor operation upto 850 C
Ceramic / Metal TubeThermocouple for incinertor
Mineral Insulated FlameProof RTD / Thermocouple
Multilevel reactor Thermocouple RTD for megnatic pump
chemical industry
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application specific products for pharmaceutical industry
Sensor with T/C end for FBD,Multicolumn, Autoclave, RMG.
T type flexible sensor for Tunnel, Autoclave.
Temperature prob for steamsterilizer/super heated steam sterilizer
RTD for Lypholiser RTD for Tunnel / DHS
RTD with mini T/C for WFI
pharma industry
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application specific products for textile industry
PRTD for Hot Godet T/C for Extruder
PRTD for Melt Transducer PRTD for Texturing
RTD for Presser Transducer
textile industry
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application specific products for plastic industry
Rapid Mixer T/C
T/C for Injection Moulding M/C
DIE T/C T/C for Extruder
T/C for Injection Moulding M/C
plastic industry
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application specific products - thermowells
Tapered T/W Flanged T/W
Fast response stepped barstock T/W
SiC T/W for protection against thermal shock / abrasionat elevated temperature up to 1200C.
ceramic T/W for temperature upto 1800C.
Sintered Tungsten Carbide T/W for protection againstabrasion up to 800C.
Hard faced T/W for protection against erosionat elevated temperature
thermowells
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application specific products - calibration instruments
Model TB-30Temperature Range: -30C to 50 C
Media: Kerosine / Methanol
Model TB-250Temperature Range: AMB +5C to 250 C
Media: Silicone Oil
Model Standard PRT / Thermocouple Model TB-1100Temperature Range: 300 C to 1100 C
Media: SS 310 Block
Model TB-600Temperature Range: AMB +5 C to 600 C
Media: Dry Brass Block
Model TB-400Temperature Range: AMB +5 C to 400 C
Media: Dry Aluminum Block
calibrationinstruments
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thermocouple for bake oven
Weather Proof Head "ET (F)Single Cable Entry
With Single Compression Cable Gland
'B' Details
InternalArragement for
MI Thermocouple
Adj. Oval FlangeDimension as per
Detail 'A"
Type: : 'N' type Thermocouple
Element : Simplex
Element Type : Ungrounded
No. of Wire : 2 Wire
Insulation : MI
Sheath MOC : Inconel 600
Dimension : As per drawing
Cable Gland : Single Compression
Head : W/P Head Single Cable Entry
T/W Const. : Drilled Bar Stock
Process Conn. : Adj. Oval Flange
T/W MOC : Inconel 601
Construction : Straight
Temp. Range : 0 to 1250 deg. C.
1500 mm
Inster MIOD 6 mm
ID 8 mm
OD 27 mm
Thermocouplewith Getter
49.5
2 Hole P.C.D. 69.5DIA 7.5 mm
21.9
57
41.5I.D.Suitebleto T/W O.D.
11
209
5 49P.C.D. 69.5
88.7
Adj. Oval Flange Detail 'A'
thermocouple forbake ovenFrequent failure of measuring elements and replacement is a waste of man hour and revenue. At TECHNO we have designed a thermocouple which doesn't require replacement of element.
SALIENT FEATURE:
* Protection tube made of drilled bar of Alloy 601. Which gives 2-3 times the life of conventional fabricated wells.
* Measuring element is hermatically sealed mineral insulated element.
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thermocouplefor boiler bedFailure of thermocouple / protectionwell, due to erosion by coal/ash, is a common problem in CFBC / AFBC boiler bed temperature measurement. We have designed a product which can perform satisfactory for long time.
SALIENT FEATURE:
* Base metal Alloy 600 has excellent resistance against sagging of 950 C.
* Overlay of wolphrom in cobalt matrix in parts erosion resistance at elevated temperature.
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3 Layer Over Lay OfWolphram In Cobact
Heat ResiatanceNickel Alloy.
OD 33.5MMWITH COATING
thermocouple for boiler bed
Thermowell M.O.C.: Alloy 600Protective Overlay: 3 layers of Wolphram in Cobalt Matrix.Construction: Drilled bar stock.
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CODE TYPE
CODE NO OF ELEMENT
CODE TYPE OF SENSOR
CODE SHEATH MOC
CODE SHEATH DIA 'D'
CODE LENGTH 'L'
CODE LENGTH ' L2'
CODE LENGTH ' L3'
CODE LENGTH ' L4'
CODE SPECIAL REQURMENT
CODE SPECIAL REQURMENT
CODE MOUNTING THREADS
CODE NO OF WIRE
CODE 'EX' CABLE TYPE
designdata sheets
Headless Sensor Assembly
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CODE TYPE
CODE THERMOWELL MOC
CODE THERMOWELL DIA ' OD1'
CODE THERMOWELL DIA ' ID'
CODE THERMOWELL END THICKNESS
CODE INSTRUMENT CONN.
CODE LENGTH 'T'
CODE LENGTH 'L1'
CODE LENGTH 'L2'
WECK FREQUENCY CALCULATOIN
Head Type Sensor Assembly Threaded Drilled Bar Stock Thermowell
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CODE TYPE
CODE NO OF ELEMENT
CODE TYPE OF SENSOR
CODE SHEATH MOC
CODE SHEATH DIA 'D'
CODE LENGTH 'L'
CODE LENGTH 'L2'
CODE HEAD TYPE
CODE HEAD MOC
CODE SPECIAL REQURMENT
CODE SPECIAL REQURMENT
CODE MOUNTING THREADS
CODE GLAND MATERIAL
CODE TYPE OF GLAND
CODE GLAND MATERIAL
CODE NO. OF CABLE ENTRY
CODE THERMOWELL DIA ' OD2'
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Weldable Drilled Bar Stock Thermowell
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Flanged Drilled Bar Stock Thermowell
CODE TYPE
CODE THERMOWELL MOC
CODE THERMOWELL DIA 'OD1'
CODE THERMOWELL DIA 'OD2'
CODE THERMOWELL DIA 'D'
CODE THERMOWELL END THICKNESS
CODE PROCESS CONN.
CODE LENGTH 'L2'
CODE LENGTH 'L1'
CODE LENGTH 'T'
CODE INSTRUMENT CONN.
CODE TYPE OF WELDING
CODE TYPE OF WELDING
CODE TYPE
CODE THERMOWELL MOC
CODE THERMOWELL DIA 'OD1'
CODE THERMOWELL DIA 'OD2'
CODE THERMOWELL DIA 'D'
CODE THERMOWELL END THICKNESS
CODE INSTRUMENT CONN.
CODE LENGTH 'T'
CODE LENGTH 'L1'
CODE LENGTH 'L2'
WECK FREQUENCY CALCULATION
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Ceramic Protection Tube Thermocouple Miniature Bearing RTD
THER MOCOUPLEWITH HOLDING TUBE
TCP1
OuteSheath
InsulationTube Element
Od1
HoldingTube
Head
L2 L1
Od
Tagplate
THER MOCOUPLE WITH SINGLEPROTECTION TUBE
& ADI. FLANGETCP2
ProcessConn
HoldingTube
Head
Tagplate
InsulatngTube Element
Od1
L2 L1
OuterSheath
THER MOCOUPLE WITH DOUBLEPROTECTION TUBE
& ADI. FLANGETCP3
InnerTube Element
Od1
Od2 Od1
OuterSheath
Tagplate
ProcessConn
CeramicBeads
Head
THER MOCOUPLE WITH DOUBLEPROTECTION TUBE
& ADI. FLANGETCP4
Head AdjcompFittingHoldingTube
InsulatingTubeOuterSheath Inner
TubeElement
Od1Od1
L2 L1
TagplateL2 L1
CODE TYPE
CODE NO OF ELEMENT
CODE TYPE OF SENSOR
CODE PROTECTION TUNE MOC
CODE INSULATING TUBE DIA
CODE ELEMENT DIA
CODE INNER TUBE DIA 'OD1'
CODE INNER TUBE DIA 'OD2'
CODE LENGTH ' L1'
CODE LENGTH ' L2'
CODE HOLDING TUBE DIA
CODE HOLDING TUBE MOC
CODE HEAD TYPE
CODE HEAD MOC
CODE SPECIAL REQURMENT
CODE SPECIAL REQURMENT
CODE GLAND MATERIAL
CODE TYPE OF GLAND
CODE TYPE OF GLAND
CODE NO. OF CABLE ENTRY
CODE TYPE OF FLANGE
CODE MOUNTING THREADS
Capsule Type : A
d
D
0.8 L
Capsule Type : B
d
L
Capsule Type : C
L
d
CAPSULE TYPETYPE 'A' ATYPE 'B' BTYPE 'C' C
NO OF ELEMENTSIMPLEX 01DUPLEX 02
ELEMENT TYPEPT-100 01PT-1000 02OTHER 03
NO OF WIRE2 WIRE 023 WIRE 034 WIRE 04
BUTTON DIA 'D'IN MM
CAPSULE DIA 'd'IN MM
CAPSULE LENGTH 'L'IN MM
CAPSULE MATERIALSS 316COPPER
CABLE TYPEPTFE / PTFEPTFE / SILICON
SS OVER BRAIDWITH OVER BRAIDWITH OUT OVER BRAID
CABLE LENGTHIN METER
M - BTD -