High-torque rotary actuators
October 2001
Pneumatics & Hydraulics
Certain applications in the oil and gas and mining industries utilise very large rotary valves that require powerful actuators to provide the high torques necessary to operate the valves.
The new 'mega rotary' range from Mitech is capable of producing very high output torques while maintaining the versatility of the tested and proven mechanisms used by the current design. These torque figures can be enlarged further through the mounting of two actuator units on top of each other. Mitech's pneumatic rotary actuator features a choice between a crank arm design which results in negligible backlash making it suitable for control applications, and a scotch yoke design which gives a high-end torque which makes it suitable for on/off duties.
The double crank mechanism is particularly well suited to metal-seated ball valves and plug valves - both of which have high run torque requirements. This is because the torque for the double crank rises throughout the stroke and means that if the actuator is sized on the end torque requirement then it will be safe in any mid-position. The scotch yoke actuator on the other hand must be down-rated so that the torque produced at mid-stroke is used for sizing.
The Mitech 'mega' double-acting range incorporates four cylinder heads around a transfer case, resulting in a compact and balanced arrangement. The torque output of the largest unit in the current range is 600 000 Nm, capable of lifting a 10 tonne weight on the end of a 6 m long beam.
Adjustable end-stops facilitate external adjustment in both open and closed positions. Pressure seals are all simple O-rings, resulting in low maintenance costs, and its single spring design makes the actuator easy to assemble and disassemble. Pneumatic or electro-pneumatic positioners can be easily mounted making the actuator well suited for modulating duty.
Mitech
(011) 462 2160
[email protected]
www.mitech.co.za
Further reading:
CompAir introduces compressed air management solution
Pneumatics & Hydraulics
To maximise savings and extend the lifespan of compressed air systems, CompAir is launching the Compressed Air Management Solution powered by Ecoplant, an intelligent system in the cloud that represents the next level in operational management, and maintain the health
Read more...
Heavy impact, smart control
Axiom Hydraulics
Editor's Choice Pneumatics & Hydraulics
Every now and then a project lands on your desk that’s equal parts heavy machinery and fine control - a tantalising mix for any engineer. A client approached Axiom Hydraulics with a project exactly like this.
Read more...
Making lines safer with smarter connection
Hydrasales
Pneumatics & Hydraulics
Imagine connecting multiple hydraulic lines or a combination of hydraulic, electrical and grease lines with one single, confident movement. That’s the everyday convenience operators get from Faster’s MultiFaster multi-coupling systems.
Read more...
Achieving clean and dry compressed air
Artic Driers International
Pneumatics & Hydraulics
Compressed air is an expensive source of motive power so it makes good sense to supply clean, dry compressed air to your distribution system.
Read more...
Navigating ISO standards in hydraulic cylinder manufacturing
Pneumatics & Hydraulics
For hydraulics professionals, understanding and leveraging ISO standards is a powerful way to ensure quality and gain a competitive edge. Here is a guide to the most critical ISO standards for hydraulic cylinder manufacturing, showing how to use them to your advantage.
Read more...
Hydraulic system upgrades to boost performance and save money
CT Hydraulics (Nqoba)
Pneumatics & Hydraulics
Those working with hydraulic or pneumatic systems know that keeping your machinery running at peak performance balances productivity and cost. As systems age, they often become less efficient, requiring more energy and more frequent repairs. The good news is that you don’t always need to invest in an entirely new machine to solve these problems.
Read more...
Top 10 questions about pressure and temperature gauges
SA Gauge
Pneumatics & Hydraulics
Some questions never go out of date, and in our industry, a few have been asked for decades. At SA Gauge, we hear them every week. Here are the ten questions we hear most often, and the practical answers that can save time, money and frustration.
Read more...
Gauge maintenance and calibration tips for shutdown or restart periods
SA Gauge
Pneumatics & Hydraulics
As the year winds down, many plants across South Africa prepare for the annual shutdown. It’s also the perfect opportunity to give your pressure and temperature gauges the attention they deserve.
Read more...
Axial piston pump series for next-gen hydraulic applications
Pneumatics & Hydraulics
Moog has launched its new AXP Axial Piston Pump Series, a next-generation hydraulic solution engineered to deliver optimal performance, reliability and cost efficiency for industrial applications.
Read more...
The role of analogue gauges in a digital world
SA Gauge
Editor's Choice Pneumatics & Hydraulics
With so much focus on digital systems, remote monitoring and automation, it’s easy to assume that traditional analogue gauges have become outdated. Yet if you step into almost any plant, mine or processing facility, you’ll still find them in daily use, quietly doing their job without fuss.
Read more...
printer friendly version