THK NRS-X / NRS Series Super-Heavy Load Four-Way Full-Ball LM Guide
The THK NRS-X / NRS Series is a full-ball LM Guide built for super-heavy loads. Its raceways are cut into deep grooves with a radius closer to the ball diameter than in conventional designs, using specialized equipment and precise cutting technique. This gives the series high rigidity, strong vibration and impact resistance, and improved damping capacity, all important qualities for machine tool applications.
While the guide isn’t cutting, it travels smoothly as normal. But when a cutting force is applied, the contact area between the balls and raceway increases, creating a mix of rolling and sliding motion. This raises friction resistance and improves damping, without adding wear or affecting service life, since the slip involved stays minimal.
Unlike a Gothic-arch groove design, the NRS-X / NRS Series avoids excessive differential slip. This lets it travel smoothly and reach high positioning accuracy even during fast feeding, making it a practical option for demanding cutting operations.
THK offers two identically sized models with different characteristics: the radial type NR-X and the four-way type NRS-X. The NRS-X / NRS Series specifically bears loads evenly across all four directions, making it a good fit for setups that need consistent rigidity regardless of load direction. There are 10 model variants, covering flanged and non-flanged types, standard, long block, and ultra long block options, with bolts mounted from above or below. Sizes range from 25 to 100, with basic dynamic load ratings from 28.4 kN to 470 kN and basic static load ratings from 52.2 kN to 920 kN, depending on the model.
