1、 - STD-AGUA SbFTULi-ENGL 1996 m Ob87575 0004870 9Tb 9 . 96FTM4 Traceable Calibration of Master Gears at PTB by: Prof. Dr.-Ing Wolfgang Beyer TECHNICAL PAPER STD-ALMA SbFTMq-ENGL L99b Ob87575 0004873 832 E Paceable Calibration of Master Gears at PTB Prof. Dr.-Ing. Wolfgang Beyer The statements and op
2、inions contained herein are those of the author and should not be construed as an oficial action or opinion of the American Gear Manufacturers Association. Abstract The PTB (Physikalisch-Technische Bundesanstalt) is able to measure (calibrate) master gears for industry traceable to national gear sta
3、ndards and in compliance with the International System of Units (SI). For this purpose primary gear standards and standard measuring devices for the reference valuesFa, F, Fp (total profile deviation, total helix deviation, total cumulative pitch deviation) being available. To calibrate the master g
4、ears of industry, PTB mostly uses coordinate measuring machines (CMMs) which are traceable by instrument-specific calibration methods. In addition, with the aid of the PTBs primary standards, a task specific uncertainty of measurement is determined for all gearing calibrations carried out for indust
5、ry, which is taken into account as correction value when the transfer measurement uncertainty is stated. Copyright O 1996 American Gear Manufacturers Association 1500 King Street, Suite 201 Alexandria, Virginia, 22314 October, 1996 ISBN: 1-55589-671-5 1 - STDOAGMA SbFTM4-ENGL L97b = Ob87575 0004872
6、779 = Traceable Calibration of Master Gears at PTE Wolfgang Beyer, Director and Professor Physikalisch-Technische Bundesanstalt, Braunschweig/Germany 1 ntrochictioa The Physikalisch-Technische Bundesanstalt (PTB) is Germanys national metrology institute whose main task consists in ensuring, the real
7、ization gnd dissemination of the SI base units on a high technical level. Furthermore, when required, the physical quantities derived from the seven SI base units, such as the geometrical measurands derived from the base unit of metre - diameter, straight- ness, roundness, involute, pitch -, are als
8、o realized at the PTB through measurement standards or standard devices. The PTB standard devices mainly serve to calibrate the reference standards of the customers, thus proving traceability to national standards. This is in part made within the scope of an accreditation within the Deutscher Kalibr
9、ierdienst (DKD = German Calibration Service) in accordance with EN 45000 and ICO/IEC Guide 25. For about 25 years, the PTB has also created national measurement standards for gear quantities for cylindrical gears and set up the relevant traceability chains. Thus the requirements according to IS0 900
10、0 and following can be met, i.e. the link-up of simple measuring means to national measurement standards is possible via a traceability chain in accordance with the International System of Units (SI). In this contribution, the three highest steps of the traceability chains for F, Fg and Fp (Fig. 1)
11、will be described in more detail. The description of the Figure 1: Calibration chain for F, Fg, Fp 2 STD-AGHA bFTM4-ENGL L99b 0b87575 0004873 b05 m fourth s:ep of the traceability chain for niesuriris WS SroeUct “jeor-“ will bt dispensed with cf. for- crorLuAiALy f bevel Csars, warzs. kcbs azZ :hz i
12、iL exa;-le. F- AZ. 3;. “t-. A., - strtsgiss for Che s-f- rLLGb2 zz-qkess 5: be men:iczed an:-. .-*-3-xi - : c_ 2 Xetional gear calibration eqtiipizat !ste i! 2.1 Profile deviations -10 _.I _- 373 qcsrii=-i -_-._- crviza :szeg 1 25 =l?= celitre:irz cyerrzrs by =be iE?Tl-2=e Se?.erzzFir. principie. i.
13、e. c:?ez ar. iwDicte is cener-tzc by line (9r 2 plzne1 without slippage. when meas-reo, rRe invoicce thus oenorate is cheorecirally ccniparei or: tho iIiv9l:Lte stanar wit3 tne invo1:te aiirfica produced befnrohani Fig. 2;. Lho trh;eabl;ity is based cri the accuracy of mesza=sz; foz -,he rol; ylinte
14、r diaicscsr aid ;?,e zcira- f tke sensr. The diaxeter measri;l5 Zevics oz the sensar Hsira Sezz caliSrsteY sgains: - ,VA recise standsrcis :Pip. 3:. fis. 4 stows :e -c- p-:.azy ,- sst sf P“, i;.val.ite stsr,Carcis which are gro?e invclrte surfaces. Sixs 1546, ihr ?TS ;?as zlsc hai mcifiei cirrcslz=
15、invclr_n sianberbs !-p rc db = 70 mi which =re s:irable for tho resk-rpecific c3liirszion of cocriinate neecuring rnacnines !Wj ir. parziculer (Fig. !. They especially serve to test the scale and guide errors during tne involute measuremenri an8 the correctness of the involute software (i: 5 0.5 TI
16、for fwd. In zhese cinilzr szanards, Che base circle-related involute surfaces are replaced by circular surfaces. The dimensional and positicnal eifferences Setweer. invdate arid circle are calculated. Fig. 6 shows tFe differences A+h between the fib. values measured by the involute software and the
17、actual ftf, values theoretically calculated for the circular involute standard on the basis of the geometrical base elements neasurrd (circle, distance). ri 3 2 - ! -.-._. r2Llins -fi a circle c= 2 cyli the draft is; available. In 1996, a new VDI Guideline will be adopted, establishing uniform evalu
18、ation criteria, for corrected gears in particular, in a mathematically unique way. 5 Reliability of industrial measurements (step 3) Within the framework of quality management systems, for at least 30 years, the German and foceigri. 5 O* d = 100 m 1.5 pip d=2Om 1,6pni d = 300 m 1.6 pm Uncertainty of
19、 UPXC 850 for fn. and Fa *=Om db=lOOnm db=ZOOm db=3OOmn with f 2 prn, the agreement was relatively good. It is provided to organize another national inter- comparison for the gear quantity “involute“ before the turn of the millennium in order to document the progress achieved by gear measuring techn
20、ology. Figure 11: pitch standard device of PTE (interval measurement 1 .- .-. I ilfpoapaarnaVma gean Figure 12: calibration chain “pitch“ Differences of recalibration ( fHa ) A E a Y Companies Figure 13: Long term stability of gear standards used in the industry 6 Investigations and national comparison measurements were successfully carried out on two bevel gear ma- sters (gear/pinion) and a special approximated bevel gear standard (results are available) - Traceability strategy for calibration of other gear quantities L 6
