Contents FEATURES MARCH 2011


SOFTWARE, MATERIALS AND COMPONENT SOLUTIONS FOR THE DESIGN ENGINEER


Mechanical Components Supplement Counterfeit


BEARINGS A grey area bearings:


Bearings... 25. Current estimates indicate that the UK grey market for bearings accounts for around 15% of total UK bearing sales, putting end users and distributors at greater risk from costly breakdowns, litigation and void warranties. Schaeffler UK looks into the problem


Belts, pulleys & chains... BELTS, PULLEYS & CHAINS Taking a vertical appoach Long lasting chain


The cover image is of Synergy, Renold’s long lasting chain


Please turn to page 27


26. Working together, Altratec Montagesysteme and iwis have developed a special-purpose accumulator chain for continuous conveyor systems


29. There are a number of installation orientations that can be considered when working with an Energy Chain cable carrier system. Justin Leonard of igus UK examines the options available to OEMs for vertical installations


Gear technology...


30. To help with product selection, we take a look at a few of the new gear products that have recently been launched in the UK


TECHNOLOGY FILE 32. Lightweight gas spring solves design problems


Applied technology Mechanical components


Bearing up under the sea


pecialised bearing solutions are available from SKF for sub- sea screw pumps. Suitable for extreme conditions, these pumps enable oil extraction as low as 3,000m in a single-step process. The bearing arrangement for each rotor consists of two CARB bearings to accommodate shaft deflection and axial displace- ment. A four-point angular con- tact ball bearing is also used to locate the shaft axially. The bearings are constructed from a tough stainless steel with nitro- gen for fatigue and corrosion resistance. Furthermore, NoWear coated stainless steel rolling elements and a specially designed cage contribute to the solution’s robustness and reliability. This arrangement can be augmented with bearing design upgrades, such as hybrid bearings with ceramic rolling elements to reduce inertial forces and heat, or special cage designs. Dr. Lars Kahlman, SKF project


S


leader, commented: “These robust solutions will help companies increase performance and well life, decrease downtime, and reduce the number of deep-sea interventions to a minimum in this emerging market for oil and gas extraction.” SKF


T: 01582 496433 www.skf.co.uk Enter 223 Design Solutions MECHANICAL COMPONENTS SUPPLEMENT – MARCH 2011 23 Meeting the challenges of quilting machine design


n response to customer feed- back, a manufacturer of home and commercial quilting machines realised a larger capac- ity version was demanded with a 6.5cm throat.


I


When developing the machine, there were a number of challenges. The first was to deal with an intermit- tent significant radial load applied as the needle pierces the quilt material up to 2,200 times a minute; and the motor drive is located at the rear of the machine while transferring motion to the


oscillating needle and foot mechanism at the front of the machine more than 6.5cm away. A minimum bearing life of 5,000,000 stitches was also needed. To meet demands, Spyraflo sup- plied a self-aligning SAE-840 Bronze bearing solution, available from Micromech. For this appli- cation, extending the outer parallel diameter and adding a second locating flange modified the self-aligning, press-fit bearing design. The resulting design allowed 10mm and 12mm diameter bearings to be dropped into the body of the


quilting machine positioned in a semi-circular nest. They were located axially by the two flanges and clamped in place by a mating semi-circular strap. The self- aligning capability facilitated easy machine assembly and resulted in smooth shaft start up with minimum friction.


Sales of the new machine have exceeded the company's expecta- tions and given engineers ideas for further developments and upgrades across the range of their existing machines. Micromech T: 01376 333333


www.micromech.co.uk A two-axis solution ensures smooth film production D


evelopment of the Glendogie Bogey animated film was a time consuming process – it was filmed by Ko Lik Films in stop frame animation, where clay models are moved frame by frame to create a sequence. Typically, 25 camera shots are needed to complete one second of film.


To overcome the inaccurate and inflexible system it was using, the company turned to engineering designer and model maker, David Campbell and his colleague Michael Gormley. Having explored motion systems, they came up with a new two-axis system. This comprises two HepcoMotion PDU profile driven units with a SmartDrive stepper motor and controller. The rigidity of the profile units


were important here – as the system is cantilevered, the vertical axis had to provide solid support for the motorised X-axis onto which the cam- era is mounted. There was also an element of ‘bounce’ in the system, but the rigidity of the beams and use of the motor to counterbalance the camera and camera head at extremes of travel ensures that this effect does not compromise the camera’s positioning accuracy. The rig is able to move the camera a set distance to within 0.1mm accuracy and most importantly


provide a datum, which is critical from a production cost standpoint. When a sequence has been shot it is naturally reviewed for quality. If part of it needs to be re-taken, it is now easy for the production team to re-shoot, for example from frame 10 – 20 in a 100-frame sequence. This is because the exact camera position is now known. Other valuable automation features are also provided by the SmartDrive controller – including knowing what distances to move the camera to achieve the required effect. HepcoMotion


T: 01844 257000 www.hepcomotion.com Enter 225


Enter 224


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52