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Schubert & Salzer Control Systems GmbH is part of the Schubert & Salzer Group,
headquartered in Ingolstadt. Core business of the company lies in the development and commercialization of innovative solutions in control technology for liquid and gaseous media fl ows.
Company employees in Germany and abroad focus their activities on customers and their requirements, while the use of the latest production technolo-gies enables Schubert & Salzer Control Systems to guarantee
FURNACES
high-end products that are subject to constant monitoring. Quality management is certifi ed accord-ing to the international quality standard ISO 9001 and ensures that the quality of products is maintained at a high level through internal and external audits as well as monitoring measures con-ducted in parallel.
OPTIMAL RATIO OF OXYGEN AND FUEL AT MELTING FURNACES
The creation of high quality glass involves, amongst other things, the precisely controlled supply of oxygen, oxy fuel and natural gas to the melting fur-nace. The maintenance of the optimal ratio of oxygen and fuel for each individual burner requires precise control. Sliding gate valves from Schubert & Salzer Control Systems offer the ideal solution for this task. The
Schubert & SalzerControl Systems:
CONTROLTECHNOLOGY
FOR LIQUIDAND GASEOUS MEDIA FLOWS
With over 130 years
of history, and ISO
9001 international
quality standard,
Schubert & Salzer
Control Systems
can certainly
guarantee the
highest quality
level for its
products. And its
core business of
development and
commercialization
of innovative
solutions regarding
control technology
for liquid and
gaseous media
fl ows, confi rms this
even more.
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most important requirement for very short reaction times for an actuator are short position-ing paths, small actuation vol-umes and low actuation forces resulting from these. All of these properties come together in the sliding gate valve. In this valve, a pair of slotted discs slide against each other transversely to the direction of fl ow. Thus, the slid-ing gate valve seals without any metallic seat.
The typical stroke between closed and open is a mere 6 to 9 millimetres. One of the most notable advantages resulting from this operating principle is the low actuation force required for the positional movements. Sliding gate valves therefore control with rapidity and preci-sion, enabling fast adaptation to the quantities fl owing through and the power required by the glass crucible.
This ensures that the oxygen/fuel supply is optimised for the fi ring of the glass furnace. After the melting process, sliding gate valves are used again to con-trol urea or ammonia for the denitration of the gases given off from the furnace (nitrogen removal process). But it is not just the glass melting process which offers opportunities to use valves from Schubert & Salzer: they are also employed for the fi ne metering of cooling air in the production of windscreen glass (for aircraft windows, for example).
Sliding gate valves from Schubert & Salzer Control Systems have DVGW approval and are available also in an EX protection version.
CONTROLLING LIQUID AND GAS FLOWS RAPIDLY AND WITH HIGH PRECISION REPEATABILITY
Normally, control valves used in process control circuits are equipped with pneumatic actua-
tors. The advantages of this design are rapid posi-tioning speed and high resolution of the valve position, both being prerequisites in achiev-ing a satisfactory stand-ard of control accuracy. However, in this case, the power supply can be a cause of concern since electro-pneumatic posi-tioners require instru-ment air which is some-times diffi cult to provide. In principle, an electrical power supply would be less problematical for this purpose, but the position-ing of motorised control valves is slow and they are subject to very high hys-teresis which makes them unsuitable for many con-trol tasks.
The new motorised actuation from Schubert & Salzer Control Systems has overcome these drawbacks as it sets new benchmarks in terms of resolution and positioning speed. The actuation of the 2030 series, compris-ing an electric stepping motor, a fl exible coupling, a gearbox and stroke detection, is designed and manufactured to a high degree of precision. The stepping motor defi nes 400 steps per revolution. Every part of the gearbox is made of steel which guarantees a long service life. Therefore, each step of the motor results in a displacement of a mere 1.5 μm. At the same time, the new 2030 actuator can achieve positioning speeds of up to 1.3 mil-limetres per second.
Furthermore, the stroke detection for posi-tion feedback consists of
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extremely sturdy metal guides, a linear potentiometer and limit switches with Hall sensors. By using a 12 bit AC/DC converter and a special interpolation pro-cess, the position of the stroke can be detected precisely with a resolution of about 3 μm. Although the sliding gate valves 8038 series combined with this 2030 actuator has a stroke of only 6 millimetres, the resolution and, therefore, the level of con-trol, are very high, taking just 4.5 seconds to open or close. With a standard dead band set-ting of a mere ± 0.2 per cent, even with these small strokes, this motorised actuator achieves a repeatability accuracy of up to ± 0.1 per cent.
These values for resolution and repeatability are better by a factor of 10 than those of valve actuators available so far on the market and are setting new standards for motorised actuators.
This motorised actuator also offers self adaptation for quick commissioning. By pushing a button, the actuator searches for the end positions of the valve. As a result, it takes the operator just a few seconds to adapt the actuator to the particular valve. Naturally, this can be done also by using the optionally avail-able communications software DeviceConfi g.
Moreover, the software also offers the opportunity to defi ne all parameters extremely easily. Monitoring and self diagnos-tic functions optimise operating reliability and simplify preventive maintenance.
Its sturdy aluminium body and separate terminal box are ideal prerequisites for harsh operating conditions, which are refl ected also in the high IP 67 protection level. The terminals are easily accessible and enable connec-tions for 230 V 50/60 Hz, 115 V 50/60 Hz, 24 V AC or 24 V
DC power supplies and set point signal connections of 0 to 20 mA or 0 to 10 V. A binary actuation (ON/OFF/STOP) with a 24 V DC signal is also available. The unit also includes a separate manual operation which can be engaged.
The new Schubert & Salzer Control Systems motorised valve offers high speed and precision for control processes involv-ing neutral to highly aggressive media fl ows in process engineer-ing, the chemical industry or plant engineering.
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SCHUBERT & SALZER CELEBRATES MORE THAN 130 YEARS OF ACTIVITIES1883
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Postfach 10 09 0785009 Ingolstadt - Germany
Tel: +49 – 841 – 96540Fax: +49 – 841 – 9654590
www.schubert-salzer.com
SCHUBERT & SALZER CONTROL SYSTEMS GMBH