What's new: bearings and linear systems
18 December 2012
Whether you want a fully integrated linear system, or just the linear guides, this selection of new product introductions chosen by editor Les Hunt may be able to help you with your search. There's news, too, from suppliers of rotary bearings.
igus UK can now offer ready-to-install combinations of motor, belt-drive or drylin lead screw linear unit for use under water or in a vacuum
Festo's new electric toothed belt axis with high feed forces and flexible motor attachments - 'ELGA' - integrates a plain-bearing guided belt drive for fast and easy positioning of lighter loads. Delivered ready-to-install, it is suitable for product handling, feeding and conveying applications in a variety of industry sectors.
The belt drive is protected by a magnetically attached stainless steel cover to guard against the ingress of dust, and its polymer plain-bearing guide runs dry, so there’s no need for lubrication, which allows its use in food processing or other grease-sensitive manufacturing environments.
Another polymer plain bearing, belt-driven configuration is available from igus UK, which can now offer ready-to-install combinations of motor, belt-drive or drylin lead screw linear unit for use under water or in a vacuum. The ZLW-1040-UW, for example, has an IP68 rated two-phase hybrid underwater stepper motor (NEMA 23) that can be operated at depths down to 10m.
If you want to build your linear units into a machine frame system, then MiniTec’s new LMS Linearmodul actuators, which are based on, and completely compatible with, its ProfileSystem range of machine framing and building components, will be of interest.
These ball screw driven units provide up to 1,400mm of travel and are housed in a 90 x 90mm extruded aluminium profile with standard T-slots on 45mm centres. The lateral slots also provide a fixing point for datum sensors and limit switches and the modular design includes a stainless steel barrier strip and cover arrangement that seals and protects the internal moving parts of the actuator.
Suitable for large area gantry, pick-and-place and robotic handling systems, LMS is delivered as standard with lubricated-for-life dual linear rail ball bearings and matched carriages that support loads in all directions.
SKF is now supplying an expanded range of modular linear profile rail guides that combine high operating speeds with heavy load capacities. Offering high rigidity, repeatability and accuracy, the LLT series comes in a wide range of sizes, with carriages and accessories to match, in various pre-load and accuracy classes. LLT profile rail guides are configured in an X-arrangement with a 45 degree contact angle between the rolling elements and raceways, providing equal load sharing in all four main load directions.
Micromech is currently quoting a one to two week delivery for Thomson 400 series profile rail linear guides, which the company describes as a cost-effective drop-in replacement offering an industry-standard envelope and hole patterns. These double-faced ball track-bearing arrangements provide equal load carrying capacity in all directions, and both caged and non-caged carriages utilise the same rail design.
Thomson offers one of the largest selections of imperial based ball screw products in Europe and these are also available on short lead times from Micromech. Multiple configurations are offered in most sizes, including round versus square body shapes, multiple circuit and load options, various mounting configurations and materials of construction.
More ball and lead screw based products are available from Haydon Kerk Motion Solutions. The BGS (Ball Guide Screw) linear rail product line is designed to position heavy loads and maintain tight accuracy and repeatability even in applications requiring significant cantilevered loading.
At the heart of the BGS08 is a Haydon size 23 (56.4mm) linear actuator driving a Kerk 303 stainless steel precision lead screw. The latter is treated with the company’s proprietary Black Ice TFE coating, which provides a permanent wear-resistant dry lubrication.
Rotary bearings
NSK recently introduced a range of high performance angular contact bearings for industrial pumps. These feature an optimised internal design that contributes significantly to lower running costs, allows downscaling of components, and saves energy by extending maintenance intervals. NSK claims this optimised design delivers up to 50 percent more bearing life compared with that of standard angular contact bearings, plus an improvement in basic dynamic load rating of approximately 13 percent.
For bearings and metal parts that are exposed directly to humid conditions or corrosive substances, NKE Austria is now offering a special galvanic coating to protect them against corrosion. The new SQ171E coating is thinner and longer-lasting than NKE’s previous product, and it can be used to protect machined surfaces such as races. It can also be used in combination with a silicate based sealing layer for even greater protection.