What buyers actually struggle with
Procurement teams specifying a 20 mm linear guideway for CNC machine tools keep hitting the same three failures. First, rails quoted as HGR20-compatible arrive with surface hardness far below the spec, so raceways brinell within months under interrupted cuts. Second, suppliers cannot produce per-batch material reports, so you cannot close the loop when your own QC rejects a batch. Third, unmatched rail-and-carriage pairs from mixed sources lose preload, and axis rigidity drifts until the machine fails a geometry re-check.
Impact on your operation: unplanned line stoppages for rail replacement, machine rebuilds under warranty, and hours of measurement work on every incoming batch.
Our engineering solution
Dongfeng manufactures the HGR series as a matched rail-and-carriage system. The rail body is high-carbon steel induction hardened to 58-62 HRC with controlled case depth, then ground in a single clamping so mounting surfaces and raceway geometry stay consistent. The four-row ball circuit (HGH/HGW carriages) distributes load across four contact lines, which is what keeps the axis rigid under heavy interrupted cuts.
Controlled hardnessSurface 58-62 HRC, verified per production batch with SGS material test reports shipped with your order.
Matched preloadZ0/Z1/Z2 preload classes let you tune rigidity versus running temperature per axis, matched at the factory.
Fit you can verifyDIN/JIS reference dimensions and mounting-hole pitch match common HGR20 footprints, so retrofits bolt on without re-machining the base.
What this buys you
- Axis geometry that survives geometry re-checks instead of drifting between them.
- Batch traceability: each order includes SGS-certified material test reports you can file directly into incoming inspection.
- Direct factory pricing on standard lengths up to 4 m, with cut-to-length and end-machining available.