The CNSLab

The HERZOG CNS Lab is the fully automated solution for elemental analysis of solids by combustion. The CNS Lab is specifically designed for the analysis of steel and iron samples in the form of stampings or chips, but can also be used for other types of inorganic material.

The CNS Lab takes over the complete process of the Sample Preparation from automatic sample receipt to transfer of the pre-annealed crucible with weighed sample and additives to the analyzer. In addition, the CNS Lab supports all steps necessary for the calibration of the analyzers, including the management of the reference samples and the definition of the calibration plan.

Depending on the volume of samples, the CNS Lab includes one robot with up to two analyzers or two robots with up to four analyzers. In the latter case, the CNS Lab ensures system readiness in case a robot is in service mode. In any case, the analyzers are rotatable and can be aligned so that they can be operated manually from the outside. For safety reasons, the robot access to the analysis equipment is then automatically closed.

The CNS Lab opens up numerous possibilities. It leads to a significant reduction in routine activities of laboratory personnel, an increase in sample throughput and an improvement in the quality of Sample Preparation and analysis.

Automatic sample reception

Production samples can be automatically received by an upstream preparation circuit. In this case, the samples are transported from the sample preparation machine to the CNS Lab by means of a pneumatic pneumatic tube system. Fixed pieces are usually punched from lug or disc samples with the help of the HUST automatic punching machine. From here, four die-cuts are sent separately to the receiving unit within the CNS Lab. In addition, milling chips can also be used for analysis after they have been automatically picked up in the milling machine and transferred to the CNS Lab. The PrepMaster control software takes care of the management of samples, forwarding of the identification numbers and communication with the analyzer.

Alternatively, samples can be entered manually by the operator. In this case, the operator registers the sample via the keypad or the integrated touch panel (option) and feeds the material via a special input drawer.

Tailor-made solutions for all analytical requirements

The CNS Lab performs all sample preparation steps necessary for successful and reliable combustion analysis. A multi-axis robot handles samples and crucibles, ensuring maximum flexibility and processing speed. Due to the modular software design of the PrepMaster, worksheets and sample routing can be easily adapted to the needs of each customer.

Batches of new crucibles (standard, ceramic, or graphite crucibles) can be easily fed into the system in trays via input drawers. Ceramic crucibles are automatically pre-annealed in a special continuous furnace. PrepMaster ensures that each crucible spends a set amount of time at the necessary temperature level. If a crucible exceeds the allowable cooling time at the output position of the furnace, it is automatically transferred to the input position to go through the heating process again.

After the punched piece arrives in the receiving unit, the sequence of the further process steps depends on the intended analysis. For a CS analysis, the robot takes a ceramic crucible from the pre-annealing furnace and transfers it to a high-precision scale for measuring the empty weight. The robot then transfers the sample to the crucible to determine the sample weight, which is further used by the analyzer. Subsequently, the crucible can be annealed to 800°C in an induction unit (option). This removes unwanted carbon adhesions, which can potentially lead to contamination of the sample surface. The robot then takes the crucible to a dosing unit for sample additions and a predefined amount of accelerator is filled onto the samples. Finally, the crucible is placed on the sample stand of the furnace and the analysis is started.

For an ONH analysis, the robot first places a graphite crucible from the input tablet on the lower electrode of the analyzer. Then the aluminum cup from the receiving unit is weighed together with the sample and the sample is entered into the airlock of the analyzer. Finally, the empty aluminum cup is weighed again to calculate the exact sample weight, which is passed on to the analyzer.

Instrument calibration with numerous options

Reference and calibration/drift samples are stored in a special shelf magazine with up to 70 positions. The magazine is easily accessible after opening the safety door and can be easily refilled by the operator. The PrepMaster makes it very easy to register new reference samples and provides a quick overview of all reference materials in the system.

Various options are available for performing calibration analyses. The PrepMaster can notify the operator on a regular basis. The operator then selects the appropriate reference samples and starts the calibration manually. Alternatively, the operator defines a calibration plan and PrepMaster automatically starts the calibration process.

The PrepMaster control system for a smooth process

The PrepMaster control system ensures trouble-free operation of the CNS Lab. It provides the operator with a quick overview of all relevant data including all production and reference samples within the system, status of the pre-annealed crucibles, utilization of the analyzers, etc. Intelligent registration procedures make the entry of crucibles and samples very easy – regardless of whether keyboard or touch panel is used as input medium. In addition, the PrepMaster ensures seamless integration of the CNS Lab with the other automation sections and analyzers.