Heat-treated tubular steel shafts

Description

Technical data

Dimensional accuracy and tolerance zones

The diameters of the precision steel shafts come in h6 and h7 tolerance zones. The adjacent table shows information on dimensional accuracy. The diameter tolerance of annealed shaft cross-sections vary slightly from the specified tolerance zone.

Measurement of straightness based on ISO 13012

The measuring points are evenly distributed between the support points and the shaft sections protruding past them. More supports are used accordingly for long, thin shafts. Straightness is half of the gauge measurement when turning the shaft 360°.

Measurement of roundness

The drawing shows the roundness of a raw shaft compared to a precision steel shaft.

a) Raw shaft

b) Precision shaft

Shaft hardness

The outer zone of the shaft is induction-hardened. Depending on the shaft diameter, the depth of hardness ranges from 0.4 to 2.4 mm. Linear and transverse surface hardness and depth of hardness are highly consistent. This ensures high dimensional consistency and long service life. The adjacent figure shows the cross-section and longitudinal section of a hardened and polished precision steel shaft. The hardened surface zone is made visible by caustic etching.

Technische Daten

Legend

Project planning information

Chamfering

When used as round guides for Linear Bushings, the ends of steel shafts must be chamfered so the ball retainers/wiper seals are not damaged when the Linear Bushings are pressed onto the shafts. The figure and table show the chamfering dimensions. Linear bushings with wiper seals cannot be pressed over sharp edges on the shaft (e.g., retaining ring grooves) since the sealing lips will be damaged.

Processing

Hardened and polished steel shafts are available in mill-cut lengths. These can be cut to size and machined to include:

• Spigots

• Female and male threads

• Counterbores

• Radial and axial holes

• Grooves

• Other machining

Unmachined, cut-to-size shafts come chamfered for accident prevention unless ordered otherwise.

Annealing machined sections

Annealing may be necessary when machining shafts due to the hardened outer zone (minor change in size possible).

Length tolerance for cut-to-size shafts

Steel shafts with smaller length tolerances are also available at additional cost.

Concentric and axial spigot runout

A review in accordance with a specified principle will be performed upon request. Values xxx < 0.02 on request.

a) about 50 mm

Mounting

Interconnected shafts – plug-and-socket connection

We also provide interconnectable steel shafts when more than the mill-cut length is needed. One shaft then comes with a spigot-and-recess arrangement, the next with a matching recess (see figure). The interconnected shaft must be supported throughout or at intervals, though generally at the joins (see Section "Shaft support rails"). The shafts must be under axial tension when fastening the shaft support rails so no gaps form at the joins. Linear bushings can simply be rolled over joints.

Certification

Safety Instructions

Downloads

	Linear Bushings and Shafts Manual | R320103669 | 2005-07-01 | English, French, German, Italian | PDF | 3.6MB Product Groups: Linear Bushings and Shafts
	Linear Bushings Catalog | R999000488 | 2015-02-01 | English | PDF | 14.9MB Product Groups: Linear Bushings and Shafts