Universal diaphragm actuator for individual control and regulating functions
March 2000Analytical Instrumentation & Environmental Monitoring
Valve & Automation
Even in the electronic age many industrial sectors make effective use of diaphragm actuators with pneumatic or electro-pneumatic positioners as standard actuators.
Short floating speed and high control forces are criterions resulting in high efficiency, reliability and especially long duty lives.
ARCA diaphragm actuators have proven themselves in the industry for more than 50 years. Anywhere where robust design, functional safety and a specially favourable ratio of costs and performance are required.
The function
Air power moves the spindle via the diaphragm against the spring tension. In the case of decreasing air pressure the spring acts in the opposite direction. The initial spring tension can be adapted to the process data by means of the spring tensioning screw. The support is connecting the actuator with the control valve. At the same time the stroke indicator is the connection to the valve spindle.
The proven ARCA modular system enables the user to combine all valve types with the UMA-types.
Important advantages
*niversal – The same type is applicable for both control and regulation functions.
*Reversible – For reversing the control action, all that is needed is to loosen four screws, flip the actuator through 180° and tighten the screws again. Planning errors can still be corrected on the spot without any problems. (Swapping normally open for normally closed).
*Strong forces – The strong springs in a solid casing made of high quality aluminium alloy are providing these actuators with control forces of up to 4 t.
*Long duty life – All parts are designed for approximately one million strokes. A special diaphragm allows a maximum operating pressure of 600 kPa.
*Mounting facilities – Provision is made for the optional inclusion of a support (NAMUR) provided for positioner, limit switches, stroke limitations or field controller. Several instruments can be mounted directly.
*Low-priced hand adjustment – For emergency operation of valves, hand adjustment devices can also be mounted subsequently.
p Few spare parts, little maintenance – The restriction to four sizes only means that only a few spare parts need to be stored for emergency cases.
WearCheck Water wins accreditation for microbiological testing Wearcheck
Analytical Instrumentation & Environmental Monitoring
WearCheck Water’s Johannesburg laboratory was recently awarded ISO/IEC17025 accreditation for Total Coliforms and E.coli Testing after a rigorous audit process, adding to the company’s extensive list of certifications, and reinforcing the laboratory’s adherence to national and international work quality standards.
Read more...Advancing process weighing and weighbridge automation
Analytical Instrumentation & Environmental Monitoring
Sasco Africa, a leader in industrial weighing solutions, is showcasing its latest innovations in process weighing and weighbridge automation.
Read more...Analysis solutions for total organic carbon
Analytical Instrumentation & Environmental Monitoring
Prepare for the future of water quality monitoring with Hach’s industry-leading total organic carbon (TOC) analysis solutions.
Read more...Liquid density analyser Sensoquad
Analytical Instrumentation & Environmental Monitoring
The SensoTech LiquiSonic system measures the density or concentration of a liquid by calculating using the sonic velocity to give output in real-time.
Read more...Oxygen measurement in beverages
Analytical Instrumentation & Environmental Monitoring
[Sponsored] Anton Paar offers a complete range of oxygen measurement instruments for total package oxygen (TPO) measurements, at-line quality control (QC), and in-process monitoring. These instruments help beverage manufacturers achieve accurate, reliable oxygen control at every stage of production.
Read more...Temperature, humidity and barometric pressure transmitter Senseca
Analytical Instrumentation & Environmental Monitoring
Senseca’s environmental temperature, relative humidity and barometric pressure transmitter, ENVIROsense has all three measurement criteria available in one device.
Read more...Analysers achieve OIML R140/MID accuracy class A certification
Analytical Instrumentation & Environmental Monitoring
Qmicro by Sensirion has received the OIML R140/MID accuracy class A certificate No. TC12537 for its DynamiQ-X GC analysers for the analysis of natural gas and natural gas blended with hydrogen.
Read more...Sustainable water management Wearcheck
Analytical Instrumentation & Environmental Monitoring
Water sustainability is critical for the future wellbeing of people, land and marine ecosystems, and socio-economic development. WearCheck Water provides a range of water analysis techniques to determine water quality for various sectors, including mining, agriculture, domestic and the healthcare industry.”
Read more...Biofilm monitoring system Instek Control
Analytical Instrumentation & Environmental Monitoring
Alvim, through Instek Controls, provides innovative, high-tech solutions for biofilm and biofouling monitoring in industrial plants.
Read more...WearCheck Water earns AdBlue/DEF analysis accreditation Wearcheck
Analytical Instrumentation & Environmental Monitoring
WearCheck Water recently became the first laboratory in Africa to be officially ISO17025 accredited to test AdBlue diesel exhaust fluid by the South African National Accreditation System.
printer friendly version