„A big thing“ – The industrial 4.0 analyzer line
The intelligent analyzer line
In high and sometimes extremely long altitudes – heated tubes are often devalued as commodity or just a normal utility item. However, they can do significantly more than just protecting liquids or gases from freezing or keeping them at a certain temperature. The latest invention from AGT-PSG shows how much intelligence can be integrated into a line for extreme cases – much to the delight of plant manufacturers and operators.
The idea for the development of the PSG hybrid line came straight from the field. It was caused by a problem (as usual): A desperate call from an operator, who described problems in his flue gas measurement, got the ball rolling. Once again, the formation of condensate in the area of the primary sample preparation (ie the gas sampling probe) and the transition to the heated line apparently caused problems. After a comprehensive analysis, it became clear that the problem was more likely to be the non-preheated backwash air, which was given up regularly to remove dust particles. It would have been possible to change this later by heating it on top of the carmine, but it would also have been extremely expensive at the same time. That’s when the idea came up: Why do we not use the heated piping to preheat the air accordingly? A new approach was born.
This approach was the starting point for a development project, by considering which additional components could be brought into the line to minimize installation and interface work at the top of the carmine or sampling site.
Template from the automotive industry
For customers in the automotive industry, sensors or supply lines have been “looped into” in addition to the actual sample line for many years. That’s the advantage of this technology: the additional elements are protected by the robust outer sheath and in addition to the connection of individual elements; it is possible to quickly and easily disconnect and connect several contacts and signals via standardized plugs. A major difference between the rather short pipes for exhaust gas test stands in the automotive industry and the application areas in the chemical or power plant: The cables do not have to be shortened locally, but are prefabricated in a defined length – a procedure that is only partially conditional on assemblies on construction sites would.
The development specification, and even the complete supply of the flue gas probe via the tube bundle, as long as possible, was awarded after successfully piloting the name PSG Hybrid Plus:
- Sample line in PFA
- Power supply of the probe
- Temperature cable for PT 100
- Calibration gas for the release of test and zero gases
- Backwash line in PTFE
Done was the overall concept of the line. As the name PSG Hybrid Plus may already reveal, some customers soon came up with the requirement to flexibly and modularly set up the basic concept. In the meantime a flexible adaptation of the components is possible via a configurator.
Can be shortened by a special shrinking technique
An essential success factor for the new development was seen from the beginning in the shortening of the lines. In particular, with long line lengths, as they may occur in environmental or process measurements, precise length measurements are almost impossible. Thus, if grinding with an overhang is to be avoided, the concept of a trim able cable is clearly superior to the pre-assembled one. Raychem heating tape technology, which has been used on AGT-PSG products for more than 30 years, offers the opportunity to cut back on almost all product lines. Still, the bigger problem was identified by the number of different components, the on-site gas – and waterproof to cut. It is due to the ingenuity of the production staff that even the PSG Hybrid Plus line can be easily shrunk with a hot-air blower via an intelligent arrangement of different dividing caps, a technology with which many assembly companies in the field of cold cables have had many years of experience.
Hard shell – to protect the special core
What advantages can a high-tech line provide with a variety of components, if not even the appropriate protection is guaranteed. By extruding the outer shell of PVC or TPU, it is ensured in any case that the pipe can withstand the harshest environmental conditions. Unlike the use of flexible polyamide hoses, the UV resistance of the mantle materials used should be emphasized in particular. In addition, the smooth surface ensures an easy installation. Damage to sharp edges or even a “snagging” can exclusively occurs in the serrated Ring-well-lines. Another advantage of the mechanical “stranding” of the analysis line is the strength that the outer jacket shares with all other components of the line. The often problematic straight laying on the carmine of other cables can be implemented with the PSG Hybrid line without additional fastening measures – the “sagging” of the cable core is effectively prevented by the tight stranding and extrusion of the outer jacket.
The heating tape technology: The engine in a heated pipe
The packaging is good. The components are held together tightly by the unique stranding technique without torsion. Still, the power must be applied properly. As for a car, the central part (analogous to the engine) is the heating cable, which keeps the set temperature and regulates it depending on external factors (such as the ambient temperature). For more than 25 years and countless kilometers of heated pipes, Raychem brand heaters have been used; the unique quality is not only reflected in the 0% complaint rate, but is further underpinned by the 10-year warranty. Whether as self-regulating version (from temperature ranges frost protection up to approx. 150 ° C) or a parallel heating cable with constant heating power, the precisely fitting product is available for almost every application.
The condensate devil hides in detail
Although the topic of heat and heat transfer is well resolved in the analysis line, this is only half the battle: In particular, the transition from heated line to, for example, the gas sampling probe, is almost perfectly suitable for a cold spot. Even the smallest unheated part can already lead to condensate formation and thus become a problem for the entire measurement. To avoid this, there are two things to keep in mind:
- The heating tape should be carried out as far as possible to the very end of the heated pipe on the sample side and must also bring the full heat output to the end.
- The introduction to the gas sampling probe has to be heated and insulated.
The two gas sampling probes PSG Basic and PSG Plus can be used as a model for this purpose. In order to ensure optimal heat development within the probe, an actively operated heating sleeve fits seamlessly to the probe. In addition, an insulating hood, which also includes the connection to the analysis line, supports the heat development ideally. All these measures contribute to the fact that the temperature maintenance of 200 °C to 350 °C can be obtained, even at extreme ambient temperatures.
Added technical value is good, but in the end, the use of a PSG hybrid line must also be commercially viable. Of course, bringing several components into one line increases the one-time purchase price. In addition, the PSG hybrid line is thicker than a conventional line due to the large number of components used in the outer diameter, which is why the bending radius increases and the installation gets more complex.
However, the actual cost-technical comparison must relate to the installation costs of the individual components on the carmine or the measuring point. If cold cables for electricity, signal cables for temperature control or even a compressed air supply for the backwash have to be installed during the installation, the hybrid concept can clearly demonstrate its advantages. In addition, a multitude of coordination interfaces are eliminated – the line comes with almost everything.
Only a single concept of many
AGT-PSG is one of the leading manufacturers with more than 2500 different tube bundles and analysis lines. As the only supplier on the market, the medium-sized company produces gas sampling probes, sample gas lines and sample gas conditioning in the form of sample gas coolers. This ensures the extraction, transport and preparation of gases from a single source – all according to the company’s vision: Perfect Sample Gas.