July-August 2021

began to supply pneumatic cylinders for Vixen’s handling processes due to the harsh environments the units are used in. Our leading cylinder seal design, life expectancy and performance mirrored Vixen’s goals for high quality and high B10d value requirements. With the development of technology and Vixen’s continual drive for innovation, we have more recently started to supply electric actuators for the company’s robotic handling processes to ensure greater control precision.” Teamwork Turnbull and his UK technical team based in Milton Keynes work with Vixen’s engineering, design and production teams normally on a monthly basis. “Both companies engineering teams work very closely together in an alliance style support venture, I think a lot of it comes down to trust and mutual respect,” says Turnbull. “We ensure we are fully aware of Vixen’s requirements whether in terms of materials, parts or technical equipment provision and, with our dedicated support structure dedicated to Vixen, we look to ensure the correct sized equipment, performance data clarification and machine safety requirements are always supported.” Keeping stock to support production Vixen is currently working on several large products, and many of the machines require both standard and bespoke equipment. “We keep a large volume of consignment stock at our Teesside site, which Metal Work manage and control the Kanban structure dedicated to Vixen,” explains Nathan Jordan, electrical supervisor at Vixen. “This mainly comprises standard air treatment units, valves and fittings sourced from Metal Work, as well as some of their smaller innovative Boxi valve islands, along with their high performance EB80 electro- pneumatic modular valve system. The benefit to Vixen is that our production facility and product requirements are supported on a weekly and monthly basis, and even with the large increase in machine orders which we have seen in 2020 and 2021, we are fully supported with a stock holding at our production facility. This ensures we can meet our own customers machine builds expectations and if required, reduce build time. Our managing director Aidan Mallon understands the constraints of supporting the worldwide manufacturing industry, and ensures we are versatile to be able to support it.” Standard and bespoke design support Turnbull also explains that, as well as delivering standard products to Vixen, Metal Work’s UK technical team also works closely with Vixen’s design and production team to provide bespoke equipment design and specification when required. “If one of the Vixen machines requires parts with special design, control and sizing configurations – electric cylinders, for example – then our UK ROM 0709-21 27/05/2021 1 PENDULAR MOVEMENT The application consists of a linear movement of the actuator which, connected to the lever mec equipment carrying the sandblast guns to make an angular (pendular) movement, with "power ar " (cyl nder) and "resistance arm" (weight equipment), which vary according to the angle, and consequently also the a cylinder. We considered an opening of 82°, with respect to the vertical: - 41°÷ 41°. The geometry, that is the fixing point of the cylinder, as well as the size and the stroke, ele successive approximations, are not completely defined. As per the following drawing, conditions have been hypothesized, amely: •fixing position, respect to the pivot point, (1000; - 800); •total length of the actuator, between rear hinge – piston rod fixing: 1080mm; ROM 0709-21 27/05/2021 2 Based on the geometry of the sketch: it would be necessary to having a stroke of approx .690mm, with the axial force on the cylinder, assuming a ma at the end of the arm, from 0 to ~800N, with a mean axial load of 400N. The worst condition is with pendulum at 41°, where the lever ratio (power arm/resistance arm) i Obviously, everythi ng depends on the real g ometries. The various frictions are not known, so we will assume an higher maximum axial force, 1000N . For each movement assuming the following speed profile with acce ration / deceleration times of 0.5s to mi inertial effects in the transients , that corresponds to a max. linear speed of 156 mm/s: We could propose: Actuator 1)Special electric actuator Elektro "ISO15552" series, size ø 50, pr cision ISO7 ball screw - not preloaded – ø16x5mm, TOTAL stroke (+)710mm (700mm useful + 10mm extra stroke for homing, ...), WITHOUT antirotation (++),geared version, with transmission belt and ratio 1/1, with brushless motor with brake “D lta”, low inertia series ECMA, 400W , IP65. (+) Total stroke is subject to be modified according the real geometrical condition. (++) For the cylinder non antirotating, it must be done externally by the mean of fixing the piston rod to so to avoid any angular movement of the piston rod. www.hpmag.co.uk HYDRAULICS & PNEUMATICS July/August 2021 49 An example of a typical cylinder sizing document that Metal Work’s and Vixen’s design departments work on as a team.