Leaders in balancing technology
Thursday, 14 April 2011 12:20
Engineering excellence is a key objective for Torin Sifan and as such this global supplier of air movement solutions sources its equipment and machinery from businesses with a similar work ethic. A strong commitment to research and development at the heart of its business has contributed to positioning Torin Sifan as the partner of choice for energy efficient air movement solutions in markets where legislation increasingly demands low carbon products.When the company embarked upon a new impeller development program, manufacturing engineers Bradley Kirk and Greg Etter approached Universal Balancing because of their past experience with them in supplying accurate balancing equipment and innovative solutions - and crucially, for their flexible and customer-focused approach.
"As a market leader, Torin-Sifan's strengths lie in the ability to not only provide a range of standard air movement products but also to meet individual customers' bespoke ventilation needs by being both versatile and flexible," comments Kirk.
"That means working closely both with them and our suppliers and responding in a way that benefits all parties. With this impeller development, we were very keen to give our customer what he required as quickly and efficiently as possible and had the confidence that working with Universal Balancing would be key to our achieving these aims."
THE ISSUES
The challenge centered upon improving the balance of a new impeller where the correction planes were less than 2 inches apart. During the development work using another supplier's balancer, Torin Sifan's engineers had attempted to balance the impeller by adding weights to the blades in two planes; however, because of their close proximity, cross plane influence was experienced which resulted in unacceptable readings, giving a relocation error of 0.5 kg with the existing tooling. After consultation with Universal Balancing two main issues were identified:
"We recognised that we needed an improved design and asked Universal Balancing if they could build a 2-plane balancer for us that would successfully deliver our goal," explains Kirk.
"The result was a machine customised exactly to fit our precise requirements while meeting the rigorous quality standards that our customers have rightly come to expect."
THE SOLUTION
Universal Balancing's solution included providing a Northfield high precision air chuck to clamp the parts to within 1 micron (repeatability) and giving a balancing accuracy of <2 gmm. To address the issue of close plane separation, the machine's suspension was adjusted and a calibration technique was employed which eliminates cross-feed between planes. This allowed optimum plane separation to be achieved in the calculated unbalance results.
The next issue to be addressed was the design of clip weights that are added to balance the part. Universal Balancing noticed that excessive pressure while adding the clips was distorting the part. This was causing the rotational axis to change, resulting in a new balance measurement requiring weights to be added at additional locations. The unbalance was in effect being ‘chased' around the part, inevitably resulting in unnecessarily excessive cycle times.
Universal Balancing custom engineered one of its standard V5S vertical 2-plane balancing machines to meet Torin Sifan's requirements. A small dampener was fitted onto the tooling and a different style of weights introduced to reduce part distortion. In addition, Universal Balancing designed bespoke weight-adding software based on its UNI-44 Windows-based touchscreen measuring system. Now, instead of needing to calculate positioning of the weight, the operators simply rotate the part by hand and the software specifies which weight needs to be added and indicates precisely where to place them in order to achieve a balanced part in the shortest possible time.
THE BENEFITS
"This software has really improved productivity," enthuses Kirk. "It tells our operators exactly which blades to place weights on, how many and at which angle - and even calculates which clips are needed on which plane. Not only that, we are achieving an exceptional reduction ratio of 98%."
With so many different air movement products being manufactured for customers - some with 11 impeller blades, some averaging 30-60, the machine is proving to be an extremely worthwhile investment for Torin Sifan for a relatively modest outlay.
"While we originally purchased the machine for a particular product development exercise, we have been able to use it with great success with several others," continues Kirk.
Universal Balancing's solution has become a critical part of the machine set-up at Torin Sifan, helping the company to save time and money in providing bespoke products, fully tested to meet customer requirements for the highest levels of quality and reliability.
"Universal Balancing not only provided the very best solution, their support and willingness to take the trouble to tailor it to our specification has been second to none," concludes Kirk. "Other suppliers just wanted to sell us a basic machine - whether it matched our requirements or not.
