Reliable process tensiometer:
- Fully automated measurement of the surface tension of process liquids
- Monitoring and controlling the surfactant/wetting agent concentration
- Continuous and discontinuous measurement (intervals or upon request)
- Automatic cleaning, callibration and monitproing
Advantages
- Quality assurance and documentation of the continuing process
- Enables automatic consumption-dependent dosing
- Highest process and product quality through optimised process control
The process Tensiometer SITA clean line ST automatically measures the Surface tension of process liquids used in the parts cleaning industry, surface technology, semiconductor and photovoltaic industry as well as the chemical industry.
The process parameter surface tension, and thus the concentration of Surface-active agents like Surfactants, wetting agents and solvents, are measured and documented inline. Connected to the plant control, the SITA clean line ST measuring system carries out an automatic dosing of active agents according to the consumption.
The process tensiometer SITA clean line ST works fully automated, including:
- Handling of process liquid
- Self cleaning function
- Calibration of the surface tension sensor
- Self diagnostic including error indication and logging
The process liquid sample is either lead back into the process again or rejected. No further equipment is necessary except of a tap water supply.
SITA application engineers develop an optimal and customised SITA clean line system solution based on an analysis of your process and plant.
Continuous monitoring and dosage according to the consumption:
- Cleaning agent component surfactant in baths of industrial parts cleaning e.g. in automotive, electronics, microelectronics and metalworking
- Wetting agent concentration of TMAH developer solutions for lithography processes in semiconductors
- Wetting agent concentration in electroplating processes
- Wet chemical process solutions in production processes with surfactant-containing liquids, such as mobility enhancers, drainage aids, slurry additives, cutting additives
Practical example: automatic cleaning agent dosing before coating automotive pistons
High Cleanliness standards of automotive piston surfaces before coating with an anti-friction-layer require a management of the cleaning agent concentration within pre-determined limit values.
The system solution SITA clean line ST continually monitors the cleaning agent components and ensures their dosage according to the consumption. Thus, a depletion or an overdose of cleaning agent can be avoided guaranteeing an optimal cleaning quality. The process reliability can be sustainably increased as well as the efficiency through to a reduction of cleaning agent.
Like all SITA Tensiometers, the SITA clean line ST process measuring device is based on the bubble pressure method to measure the dynamic surface tension in liquids. For this purpose, an air stream is fed into the sample liquid through a Capillary which is especially developed for process use.
The bubble that is formed at the end of the capillary continually expands its surface area. When the bubble radius reaches its minimum, the bubble pressure rises until reaching its maximum value. The surface tension is then calculated by determining the difference between the pressure maximum and minimum values.
| Surface tension | ||
|---|---|---|
| Measuring range | (10...100) mN/m (dyn/cm) | |
| Resolution | 0.1 mN/m (dyn/cm) | |
| Reproducibility | 0.5 mN/m | |
| Liquid temperature | ||
|---|---|---|
| Measuring range | (0...80) °C, depending on the measuring | |
| Resolution | 0.1 K | |
| Measurement deviation | 1 K | |
| General data | ||
|---|---|---|
| Housing |
750 mm x 400 mm x 240 mm (HxWxD), Stainless steel (1.4301) | |
| Weight | ca. 23 kg | |
| Acceptable surrounding temperature | (10...40) °C | |
| Liquid tangent materials | ||
|---|---|---|
| Metal vessel type | Stainless steel (V2A & V4A), PTFE, FKM (viton), PEEK, PU, PA, PP | |
| Glass vessel type | Stainless steel (1,4401, 1,4408, 1,457l), borosilicate glass, PTFE, FKM (viton), PEEK | |
| Teflon (PTFE) type | Stainless steel, PTFE, PFA, PVDF, PEEK | |
| Electrical connections / interfaces | ||
|---|---|---|
| Power supply | 24 V, 60 W | |
| Communication interface | PROFINET | |
| Status messages | Error/interruption, overrange and underrange surface tension, potential-free contacts | |
Publications
- Who cares about surface tension? / 2021
- Defining limit values for sufficient parts cleanliness / 2019
- Tensiometrie for monitoring the concentration of cleaning agents / 2014
- Analysing and monitoring surfactants - Process parameter surface tension / 2012
- High Process Reliability of Industrial Cleaning Processes by Measuring the Surfactant Concentration / 2012
- Controlled Cleaning by measuring surfactant concentration / 2009
- Automatic Dosage of Cleaning Agents and Efficient Cleanliness / 2008
References
SITA measuring devices have been successfully used in a variety of applications worldwide for over 25 years. The companies listed here represent just a small
selection of our extensive customer base.
Simply get in touch with us. You can find the contact details of our sales and application department under contact persons.
For support in your country, please see our international sales partners.
Alternatively, send an e-mail to info@sita-messtechnik.de, call us at +49 351 288 53-0 or send us a message using the contact form.