Text from page 43 of catalogue Recirculating bearings
Page 43 of catalogue Recirculating bearings of PM Bearings B.V.Recirculating Systems PNUA needle roller type
PNUA linear guides are designed to support extremely high loads, while ensuring maximum rigidity and high degree of precision in every orientation. PNUA guides are orginally created for the machine tool industry but also used in many other applications as grinding machines and stamping presses. PNUA needle roller bearings are designed so that they can carry extremely high loads and moment loadings in all directions due to the X-arrangement of the needle rollers. In cases of A >1400mm we supply multi section lengths which are matched together and marked accordingly. PNUA tables consisting of one 4-row rail, one table, two recirculating cassetes (per cassete two recirculating units) and depending on the operation conditions two endseals. No 1. PMR 4-row Trackrail (page 44) PMR rails are 4-row precision guides providing spacesaving solutions. They are manufactured from high quality bearing steel 1.2842, through hardenend 60 +/-2Hrc. PMR rails can be bolted down into the application. They are available in 3 sizes and several standard lengths. No.2 PMT Table (page 45) PMT tables are used to attach and preload the recirculating units to the PMR rails. They are made cast iron offering excelent damping characteristics. The tables include standard countersunk attachment holes for the recirculating units and 6 threaded holes. Tables are precision ground and provide space-saving solutions. The lateral adjustment holes are to install the preload screws. For higher loads we can supply longer carriages so that two units can mount the one behind another. Tables are equipped with lubrication ports for relubrication from the side.
No. 3 PNE – Recirculating Units (page 48) PNE recirculating units are double row needle roller bearings for high to extemely high loads. They can be used in every orientation. The main body in made of high quality bearing steel 1.2842 and through hardened at 60 +/- 2Hrc and precision grounded. The special designed return offers extremely smooth running characteristics without skeewing. All needles are retained to prevent them from dropping out. No. 4 PMA Endseals PMA endseals are an effective and economical solution to protect the PNUA-guides in operations where dust, dirt and other contamination are present. They are installed on both the front- and backside of the PMT table and during travel they are cleaning the running surfaces grooves and the rail uppersurface. PMA endseals increase the operational reliability even under the most strenghten conditions. For other sealing requirements please consult PM.