Tube Resistance Thermometer TP 21 Hengesbach

 The Tube Resistance Thermometers Type TP21 meet, by their design layouts, the requirements for a deadspace-free and hygienic measurement in all kinds of fluid media, like e.g. milk, beer, juice etc. The measurement occurs without a profile modification and without contacting the media by the sensing resistor, taking into account the good response times. Therefore e.g. cleaning procedures by a pig etc. are possible.

Tube Resistance Thermometer TP 21 Hengesbach

The device consists of a pipe body with neck tube in stainless steel. Integrated in the pipe body is a PT100-thermometer. Optionally the measuring insert contains one or two measuring resistors PT100, connected via the terminal block of the housing head in 2-, 3- or 4-wire circuit. The temperature sensors are to be integrated in the pipeline. Different connection versions for varying applications are available.


  • deadspace-free temperature measurement
  • no contacting with media
  • for food and pharmaceutical industries
  • entirely in stainless steel
  • corrosion resistance by field housing
  • custom-designed process connections
  • optional with transmitter


Constructive Layout

Housingfield housing 
Temperature sensorPT 100 acc. EN 60751, changeable measurement insert (Standard), 
 insert tube 1.4571 
Measurement insert, electrical1 x PT 100 in 2-, 3- or 4- wire connection, standard: 1 x 3- wire connection, 
 2 x PT 100 in 2- or 3-wire connection 
Electrical connection- M16 x 1,5 – cable gland, MS nickel-plated, 
 - optional: M12 x 1 circular connector, 4-pins 
Accuracy- standard: tolerance class A acc. to EN 60751, 
 - optional:tolerance class B 1/10, 1/5, 1/3, 1/2 DIN
Response timeT50 (measured in water): 6 sec. (dependent on design, d = 6 mm) 
 < 4 sec. with tapered sensor tip on request 
Measured medium temperatureTmax at sensor =-20... +200°C
Housing materialstainless steel 1.4301 (CrNiSt, standard-field housing) 
Measuring section - materialstainless steel 1.4571, optional 1.4435 or 1.4404, 
 optional: tube in polished steel 
Protection classEN 60529,IP 67 with cable gland, optional with cable connection
Pressure admissiblePN = 10 bar 
CE-conformityEMC-rules are fulfilled, CE-sign 

Process Connection

 - TP21 / TW 59...T108 
  milk pipe screw joint with threaded double-sided neck, DIN 11851, DN20...DN100,
 - TP21 / TW 59...T141 
  Tri-Clamp-connection acc. to ISO 2852
 - other connections on request (please specify nominal width) 
 - neck tube:38,5 mm x d = 16 mm (acc. to drawing)
 - measuring section length: 
  120 mm (acc. to drawing)


Assembly componentsNone 


Electrical connectionceramic connection socket 
 flexible connecting wires 
 sheathed cable(shakeproof type)
 transmitter TE 42, programmable, 4...20 mA, 2- wire connection (standard) 
 transmitter TE 41, programmable, galvanically isolated 
 transmitter TE 52, HART 
 transmitter TE 82, Profibus PA 
Calibrationfactory calibrated, calibration certificate (3-point or 5-point), with DKD-standard 
Certificatesmaterial certificate, acc. to EN 10204 


Another Article: 

Thermax 4 Level Strips Irreversible Labels
Thermax Clock Indicators Irreversible Labels
Hengesbach Temperature Measurement
Thermax 6 Level Mini Strips Irreversible Labels
Thermostrip DS - Thermax