Product category:
Bearings and guideways - rotary and linear
News Release from: SKF UK | Subject: Recirculating roller screw
Edited by the Manufacturingtalk Editorial
Team on 29 January 2007
Recirculating roller screw application
14 years on
Varian Medical Systems specified a recirculating roller screw from SKF to provide the accuracy, precision and load capacity required for the positioning and lifting of its cancer treatment couches.
Over 14 years ago Varian Medical Systems, the leader in integrated radiation therapy systems, specified for the first time the use of a recirculating roller screw manufactured by SKF, the world's leading knowledge engineering company, to provide the accuracy, precision, rigidity, reliability and high load capacity required for the positioning and lifting of its Clinac, Ximatron and Exact cancer treatment couches Over 4,000 medical couches without a single failure later, the partnership is still going strong to ensure the manufacture of some of the most superior medical couches available, allowing optimum patient treatment, comfort and safety
This article was originally published on Manufacturingtalk on 19 Apr 2004 at 8.00am (UK)
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Oncology, or the treatment of cancer, requires equipment that can provide ultra precise positioning with incredible levels of reliability.
The location and treatment of a cancer tumour requires patients to be positioned under a high energy treatment beam to receive a series of carefully controlled and accurately targeted doses of radiation, spread over a number of weeks.
Accordingly, the height of the treatment couch is crucial in order to ensure precise and repeatable targeting of each individual patient within the radiation treatment beam.
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Throughout its operating life, a medical couch will be expected to position 25 patients a day with an average of six movements per patient, equivalent to around 375,000 separate cycles.
Each movement must be extremely smooth, trouble-free and accurate to within +/-1mm, as any greater positioning error could have a direct impact on the effectiveness of the cancer treatment.
It is for these reasons that the SKF recirculating roller screws were selected at the outset.
Most importantly, they have been designed to perform with absolute precision, while offering exceptionally high levels of rigidity, repeatability and long-term reliability.
Additionally, the high performance units allow finite positioning due to the fine lead of 1mm for screws with a diameter between 8mm and 50mm.
A further mechanical advantage of the rollers screws is that they only require low input torque from the drive, increasing its resolution. Request a free brochure from SKF UK ...
Derek Flanagan, UK Manufacturing Manager at Varian Medical Systems, commented, "The high quality manufacturing and construction of SKF's products and proven operating efficiency they offer enables us to design and manufacture some of the world's leading cancer treatment beds, while the outstanding product availability and reliable delivery service allows us to optimise our production performance." He continues, "We aim to continue to work closely with SKF and look forward to further develop this and future applications, ultimately, so that we can keep providing cancer patients with the best possible treatment options in the battle against this terrible disease.".
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