通用拧紧规则.

1、 Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.1 Can be loosened without destruction High constant clamp load Reliable achievement of

2、 demanded clamp load Does not become loose as a result of operational force Demands of a bolted joint Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third

3、parties. K.2 S.2 Important tightening factors Torque Clamp load Under head friction Settling Thread friction Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on

4、 third parties. K.2 S.3 Influence of friction Thread friction approx. 30% . . . 40% Underhead friction approx. 40% . . . 50% Clamp load r Underhead and thread friction influence essentially the clamp load, i.e. up to 90% friction losses may appear using torque controlled tightening methods Tightenin

5、g Torque 100% Approx. 10% Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.4 Clamp load too low or too high Incorrect tightening system

6、Friction Rough surface Poor quality screws Unsuitable material Unreliable Assembly Technique Inaccurate or suitable tools Poor quality screws Inaccurate workpieces Setting Design flaws Unsuitable material pairing Incorrect tightening methods Temperature Different coefficient expansion Incorrectly di

7、mensioned bolted joint Factors influencing clamp load Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.5 Variation of assembly-clamp loa

8、d for torque controlled tightening Maximum torque of the tightening spindle and minimum friction FM min Minimum torque of the tightening spindle and maximum friction FM min r Safe process for: Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in

9、the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.6 Load extension diagram (VDI 2230) FM Clamp load fSM Elongation force of the screws fPM Press force on the material (compressing of the material) Lengthening Shortening Tightening and press-fit

10、 systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.7 Load extension diagramVDI 2230) with acting operating force FM Clamp load fSM Elongiation force of the screw

11、fPM Press force of the material (compressing of the material) fSAActing operating force fPAReduction of press force FPAAxial force, relief of the clamped parts FKRResidual clamp-load FSTotal force (clamp load and operating force) FAAxial screw-force FSAOperating force Tightening and press-fit system

12、s Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.8 Load extension diagram (VDI 2230) with settling effect fSM Elongiation force of the screw fPM Press force of the mat

13、erial (compressing of the material) FM Clamp-load FZ Amount of clamp-load fZ Reduced force because of settling influences FV Remaing clamp-load Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all ri

14、ghts of disposal such as copying on third parties. K.2 S.9 Clamp-load variation as a function of torque variation (from VDI 2230) Variation of tightening torque T % Clamp-load variation FV% Al Mg Si 0,5 St 37 K drawn St 37 K milled Ck 65 ground GG grey cast iron, planed Tightening and press-fit syst

15、ems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.10 Influence of tightening method and tightening equipment on a bolted joint Tightening and press-fit systems Tighte

16、ning basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.11 r Torque controlled (1) Overview of tightening methods AF A T TF:T (1) (2) (3) r Yield point controlled (2) r Angle control

17、led (3) Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.12 r Torque controlled, angle monitored Torque controlled tightening method r A

18、pplication examples Easy accessible measurement Transmission assembly Use of standard screws Re-use of screws Joint errors detectable Manifold assembly Wheel assembly T T+ TF:T T- TT A0 A- A+ A Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in

19、 the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.13 r Yield-point controlled, torque/angle monitored Yield-point controlled tightening method r Application examples Minimum friction influence ABS-assembly Less clamp-load variation Limited re-

20、use of screws Wheel hub assembly Disk fly-whell assembly Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.14 Requirements for yield-poin

21、t tightening Joint must be designed for yield-point tightening Bolt reaches plastic elongation Material under the bolt head or in the thread is not allowed to flow Thread friction must be siginificantly less than the underhead friction Workpiece and spindle must be firmly mounted Stick slip is not a

22、llowed to occour Adjustment of the parameters must be based on the tightening tests (length measurements) Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on th

23、ird parties. K.2 S.15 r Angle controlled, torque monitored Angle controlled-tightening method Minimum friction influence r Application examples Cylinder-head assembly Less clamp-load friction Screws not re-useable Caliper assembly T T + T - TT A A0 A- A+ TF:A Tightening and press-fit systems Tighten

24、ing basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.16 r Description Multi-stage tightening methods in general Through menu-driven programming, tightening sequences can be freely

25、created A T SearchScrew-in Tightening Easy adjustment of the tightening sequences on the application Interlink of the standard tightening methods Freely defineable monitoring criteria in every tightening step Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all

26、 rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.17 r Description Thread cutting tightening method Searching“, torque controlled Cutting“, angle controlled Screw-in“, torque-controlled Tightening“, torque controlled angle monit

27、ored r Application examples Bolted joint with sheet metal screws T Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all rights even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.18 r Description Scr

28、ew in with depth control Screw-in“ with depth control (external switch-off signal), Screw-in torque or final torque are monitored r Application examples Screw-in of adjusted screws Screw-in of studs A T Tightening and press-fit systems Tightening basics AT/PSE-PM Robert Bosch GmbH reserves all right

29、s even in the event of industrial rights. We reserve all rights of disposal such as copying on third parties. K.2 S.19 r Description Recognition of thread defects Tightening 1“, torque controlled r Application examples With rough and brittle materials Backout, angle controlled, torque monitored Tightening 2“, torque-,angle- or yield point controlled (recognizing scuffing“) Tightening and press