Chemical | Petrochemical | Oil & Gas | Sanitary applications

Special solutions withelectrical thermometers

Alexander Wiegand,
Chairman and CEO, WIKA

About usAs a family-run business acting globally, with over 9,300 highly
qualified employees, the WIKA group of companies is a worldwide
leader in pressure and temperature measurement. The company
also sets the standard in the measurement of level, force and flow,
and in calibration technology.
Founded in 1946, WIKA is today a strong and reliable partner for
all the requirements of industrial measurement technology, thanks
to a broad portfolio of high-precision instruments and comprehensive services.

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With manufacturing locations around the globe, WIKA ensuresflexibility and the highest delivery performance. Every year, over50 million quality products, both standard and customer-specificsolutions, are delivered in batches of 1 to over 10,000 units.
With numerous wholly owned subsidiaries and partners, WIKA
competently and reliably supports its customers worldwide.
Our experienced engineers and sales experts are your competentand dependable contacts locally.

Contents
Temperature profiling in reactors

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In furnaces and combustion chambers

6In corrosive media

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Robust and safe

10

For abrasive loads

12With high pressures

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In sterile processes

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Exact calculations

18

Best connections

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Special applications in electricaltemperature measurement
In the area of electrical temperature measurement, within its
standard portfolio, WIKA already offers an extensive
selection of products and accessories for a wide variety ofapplications.
In addition to this, customer-specific solutions represent a
key element of the electrical temperature measurement

product range. These are developed, manufactured andtested individually for your applications.
As a further service, we offer on-site installation of themeasuring instruments. Our service teams operateinternationally and are happy to come to you.

WIKA measuring instruments are available withnumerous approvals and certificates.

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Multipoint thermometers for radial
multipoint measurements inpetrochemical processes

Temperature
profiling inreactors
Processes in chemical or petrochemical plants demand
diverse, and often highly specialised measurements of theprocess parameters.
WIKA and Gayesco have over 60 years experience in thedevelopment and manufacture of temperature measuring
instruments for industrial applications. For example, multipoint
thermometers can be implemented for the recording ofcomplex temperature profiles in reactors. One important task
also fulfilled by multipoint thermometers is in the detection oflocalised heat concentrations (“hotspots”) or in the detectionof critical exothermic reactions - known as “thermal runaway”.

Radial arrangement of thethermocouples within thereactor

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A division of the WIKA group5

Left: Different solutions for tubeskintemperature measurement

Centre: Technicians from the WIKA/Gayesco service team during theinstallation of a REFRACTO-PAD®
Right: WELD-PAD with guidechannel and heat shield of theXTRACTO-PAD®.

6High-temperaturethermocouples with various
thermowell materials®

A division of the WIKA group

In furnaces andcombustion
chambers
Measurements in industrial furnaces with temperatures of up
to 1,700 °C (3,092 °F) represent a challenge.
The individual selection of the materials used and decades ofexperience in the design and manufacture of thermocouples
for high-temperature operation form the foundations forprocess safety.
Through the accurate monitoring of the pipe temperature incombustion chambers, an optimal efficiency is ensured forthe plant.
On request, the expert mounting of the temperature measuring instruments can be carried out by a WIKA/Gayesco
service team.

High-temperature thermocouple in Ex version

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Double safety through primary andsecondary safety chambers for theconnection head

Robust and safe
Special process conditions, such as those which prevail ingasification reactors or GtL processes, require tailoredsolutions.
The 3-times longer service life at temperatures up to 1,700 °C(3,092 °F) in process pressures of up to 65 bar (943 psi)enable a reduction of plant downtime.
The sapphire protection tube shields the precious metal
thermocouple from poisonous process media. This enables
cost savings by eliminating the use of expensive purging
systems which are typically used in these applications toextend sensor life.

Double protection of the thermocouple
through a ceramic exterior protection
tube in combination with a sapphire
inner protection tube8© The Linde Group9

Coatings made of plastic or withtantalum cover protect against
corrosive media.

In corrosive media
High corrosive loads due to aggressive process media placehigh demands on the thermowells used.
Through the individual engineering and the variety ofavailable materials, special alloys and coatings, themeasuring point can be optimally adjusted tothe process requirements.
All safety-related design specifications and customer
requests can be taken into consideration when
designing the measuring point.

Measuring point as a cutaway sample

with forged Hastelloy thermowell inVanstone design

10The right coating for each use

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Stellite® thermowell using Air Plasma

Spraying (APS) for generalapplications, e.g. in sewage treatment

plants or in the paper industry

For abrasive loads
Hard and abrasive components in the media are everyday
occurrences for many processes. They frequently lead topremature failure of equipment.
With abrasive loads, using suitable materials such as
Stellite®, significantly increases the service life.
Various processes for the Stellite® coating ensure a highprocess reliability in a multitude of high-load applications
such as e.g. FCC units.

Stellite® coatings using laser

cladding or PTA processes
up to 3.2 mm thicknesses,e.g. for use in FCC units©TTstudio _Shutterstock1314

High-pressure thermocouple
with lens-type sealing ringWith highpressures
The process of manufacturing LDPE (Low Density Poly­ethylene) is made at pressures of approx. 3,000 bar(43,500 psi), where the temperature curve in the highpressure tubular and autoclave reactors is an important
process variable.
Specific materials with high-yield characteristics and special
manufacturing processes such as vacuum soldering, ensure
the high quality of these products, individually matched toyour requirements.
Each high-pressure thermocouple is designed and manu­
factured in accordance with customer requirements. Throughpressure testing up to 6,000 bar (87,000 psi), we ensure thehigh demands on safety and reliability.

High-pressure screw-in
thermocouples

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Multipoint thermometers for

temporary measurements oftemperature distribution in reactors

In sterile processes
The particularly high requirements of sanitary applications
are ensured through the use of approved materials, thelowest surface roughness and patented dead-space freeconnection geometries for thermowells for orbital welding
into pipelines.
Dead-space free multipoint thermometers with the shortestresponse times are just one example of an application-specific special solution.

Thermowell TW61 for orbital welding(Patent DE 102010037994,US 12 897.080)

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Representation of the flow

conditions for a dead-space freethermowell vs. conventional
design with collaring

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Left: Kármán vortex street for athermowell with an incident flow
Right: Diffuse vortex shedding
behind a thermowell in

ScrutonWell® design

Exact calculations
To prevent the failure of thermowells, in particular at high flow
rates, WIKA offers the design calculation in accordance withASME PTC 19.3 TW-2016.
For designs outside the validity of this standard, an FEM
calculation can be carried out.
In order to effectively dampen the excitation leading tovibration, the new ScrutonWell® design can be used.

FEM representation of thepressure and bending load
for a flanged thermowell

Flanged thermowell in
ScrutonWell® design19PMI test

Best connections

Liquid penetrant
inspection

Tested and approved welding procedures, as well as thepossibility of extensive non-destructive testing in accordancewith internationally recognised standards or customerrequirements ensure the quality of our products.

Radiographic
examination

WIKA Alexander Wiegand SE & Co. KG
Alexander-Wiegand-Straße 30∙63911 Klingenberg∙Germany
Tel. +49 9372 132-0∙info@wika.de∙www.wika.de14139919 04/2023 DE

We are happy to advise you on further
customer-specific solutions.