SBR Supported Round Shaft Rails

The base determines how the rail fits the machine

The round shaft is only one part of the SBR rail profile. Beneath it, the support widens into a mounting foot with fixing positions on both sides. The shaft provides the running surface for an open linear bearing block; the foot provides the connection to the stationary machine structure.

Three dimensions describe this arrangement particularly well: shaft diameter, base width B and transverse fixing-hole spacing C. Shaft centre height h establishes the position of the guide axis above the mounting surface. These dimensions change together across the range, so increasing shaft diameter also changes the space occupied by the rail.

Selected cross-section dimensions from Guangyuan's SBR drawing:

SBR16 and SBR20 illustrate why a single mounting dimension cannot establish interchangeability. Both have 30 mm transverse fixing-hole spacing and a 5 mm base thickness. However, SBR20 has a wider base and places the shaft centre 2 mm higher. Its larger shaft also requires a corresponding bearing block. A shared hole spacing therefore does not make the two assemblies equivalent.

From the moving bearing to the stationary bed

During operation, the bearing block travels along the exposed shaft surface. Its lower opening clears the support underneath. Load passes from the moving component through the bearing and shaft into the support and machine bed.

SBR Supported Round Shaft Rails use this continuous support to reduce the freely spanning shaft length associated with end-supported arrangements. The result still depends on the bed beneath the rail: an uneven mounting surface can distort the installed guide, and loose or poorly seated fixing points cannot provide the intended support.

The catalogue specifies longitudinal fixing pitches of 100 mm for SBR10–13, 150 mm for SBR16–20 and 200 mm for SBR25–50. These pitches describe the standard mounting pattern along the rail, whereas dimension C describes the spacing across it.

The rail drawing does not provide a complete carriage load rating. That requires the selected bearing blocks, their spacing and the direction and position of the applied load. Likewise, shaft centre height h is not the height of the assembled carriage. For SBR Supported Round Shaft Rails, the rail profile and bearing-block drawing describe different parts of the same mechanism and should remain clearly identified.

About Us

Lishui Guangyuan Industry & Trade Co., Ltd. produces supported rails, linear shafts, bearings, ball screws and related motion components.

We supply SBR rails and matching open bearing blocks, with drawing-based OEM/ODM services available for nonstandard requirements. The minimum order quantity for these rails is 10 rails. Rails and bearing blocks can be specified separately to suit the required assembly.

Hot Tags: SBR Supported Round Shaft Rails, ChinaSBR Supported Round Shaft Rails suppliers, manufacturers, factory, CNC Slide Rails, Linear Guide Rail CNC, Linear Motion Ball Bearing Slide, Linear Motion Ball Slide, Linear Slide Guide Rail, SBR Linear