Contamination control of hydraulic and lubricating oils

Paul Boughton

Boris Mette outlines the benefits of a laser particle counter available with ATEX certification for use in areas prone to explosion.

LasPaC II-I (Inline) Laser Particle Counters from Stauff were developed for continuous monitoring of the contamination of mineral oils and petroleum based fluids. Units that are compatible with Phosphate Ester and Water Glycol are available on request.

Permanent installation of the particle counter in the fluid system makes it possible for the user to respond immediately to increasing contamination in the fluid, to reduce downtime of the system, and to protect it against costly failures. The device is very easy to connect to the system by means of two hydraulic test couplings of type Stauff Test 20 (adaptation thread M16x2). That way, subsequent installation of the unit is not a problem.

LasPaC II-I (Inline) Laser Particle Counters work according to the 'light blockade principle' in which two lasers shine through the liquid to be measured and illuminate a photodiode. If contamination particles in the fluid pass through the laser beam, the total amount of light that reaches the diode is decreased. Since this change is directly proportional to the size of the particles, it is possible to determine the degree of contamination from this. In the process, the unit analyses all particles inside the measuring cell as well as particle sizes that are smaller than 6μm(c). That way, inaccuracies that can arise through partial capture or extrapolation are avoided.

The exact degree of contamination is classified in eight channels between 4μm(c) and 68μm(c). Hence, the LasPaC II-I allows for a more accurate and more complete determination of the particle sizes than other units available in the market, and also makes it possible to assess contamination in coarser ranges.

The results of up to 600 standard measurements are stored in the internal memory and can be transmitted over the RS-232 interface or a USB adapter to the PC or laptop. Furthermore, an optional external monitor is available for the direct display and real time analysis of the data, which provides a way to start and stop measurements as well as to actuate the integrated flush valve. It is also no problem to install the LasPaC II-I directly into existing machine systems thanks to the optional integration of a Modbus interface.

As additional accessories, the company also supplies a coarse pre-filter to protect the unit, water-in-oil and temperature sensors, as well as sampling sets and bottle sampling units, which make subsequent analysis possible.

For use in areas that are prone to explosion, Stauff offers a special variation of the LasPaC II-I with ATEX certification (zone 2/category 3G). This classification was realised through a modified design of the housing and connectors. Hence, the unit meets all the requirements for use in the oil and gas industry or in chemical and process technology.

Enter X at www.engineerlive.com/ioe

Boris Mette is with Walter Stauffenberg GmbH & Co KG, Werdohl, Germany. www.stauff.com