RESEARCHERS FOR DETERMINATION THE AXIALREINFORCED CAPACITY OF BALL BEARINGS ANGULAR CONTACT FULL CERAMIC MATRIX COMPOSITE BALL BEARINGS

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1 5 th Intrntonl Confrnc Computtonl Mchncs nd Vrtul Engnrng COMEC Octobr 013, Brşov, omn ESECHES FO DETEMINTION THE XILEINFOCED CCITY OF BLL BEINGS NGUL CONTCT FULL CEMIC MTIX COMOSITE BLL BEINGS Ion Enscu Trnslvn Unvrsty Brsov, Fculty of Mchncl Engnrng, Mchncl Engnrng Dprtmnt 5007 Brsov, omn, E/ml bstrct Th bll brngs r unvrsl usd. H ssum th rdl forc but nd th l forc nd compos forc (rdl nd l). Th clculus of th ngl of contct nd rspctvly th zon of contct s vry mportnt. Full crmc-mtr compost ngulr brngs md ntrly of crmc compost /mtrl nd r supror to common stll ngulr contct brngs n mny wy. Kywords: contct,ngulr, bll, brngs, crmc, compost 1.INTODUCTION Th norml tnsons whopprs n th ntrcton btwn th blls nd th rollng wy n th cs of rdl lod of th brng r dstrbutd nto n llpsodl r. In fg.1 s prsntd th llpsodl contct r btwn th bll nd th rollng wy of ntr nnr.th mjor s s symmtry n th wdth of rollng wy. In th cs of combnd lod (rdl-l) or pur l, th bll movs to th bord of th rollng wy, t constnt ngl α, th contct llps my b mprfct, rspctvly th contct tnson s mm to th bord of rollng wy. 76

2 Fgur.1 Fgur. Th tnson n th mprfct contct llps r mjor tht n th cs of th tnson n th contct llps t rdl lod of brng. For vod th pprnc of sm cssv tnsons n th bord zon of rollng wy s mjor ncssry to clculton th ngl of contct α thn th mjor s of llps s prfctly..the DMISIBLE NGLE OF CONTCT CLCULTION In th cs of th problms s:- wht mjor s th α ngl thn th prssur llps r prfct (th mjor rst n th rollng wy). In fg.1 s prsntd th stuton tht th rdl brng r lodd wth rdl lod In fg. th lod s 1 + for th most lodd bll. For th ccntrc contct llps do not pss th bordr of th rollng wy to b stsfd by th nqulty (fg.3) (1) s rb h cos s r sn d spctvly th nqulty (1) r vrfy wth b b rcsn r cos s If not, th contct llps pss th bord of rollng wy nd mplct th tnson n mrgnl zon r ovrfulflld. Fgur.3 77

3 Notton fg.3 = numbr of bll = totl rdl lod = l lod/bll r b = d b /-ry bll r c = ry of rollng wy = mjor s of contct llps j = dmtrcl workng h = dpth of rollng wy just t nnr shouldr c = ngl btwn th cntr of contct llps on tror wy = ngl btwn th cntr of contct llps wth symmtry s of brng = ngl btwn th symmtry s of nnr nd th bord of rollng wy s = ngl dtrmnd by th cntr of contct llps wth th bord of rollng wy 3. THE CLCULTION OF LIMIT XIL LOD Th rlton Hrtz-Blvprmt th clculton of th s of th llps of contct, lstc dformton nd th mmum untry ffort [mm] () nd [N] ( 1 [1/mm] ) I ( 1 ) II - ρ 1 nd ρ r th curvturs of th bll n th plns I nd II, rspctv th mnm nvrs vlu of curvturs rys - prmtr of functon F(ρ) th prmtr tg s don by dgrm (fg.5) () ( r c r) 78

4 For th most lodd bll w hv: -nd from () rsult lm nd 5 ( rc rb ) ( r c 5 r ) Fgur.4 * 3,8 3,4 3,0,6 0 0,1 0, 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 F () Fgur.5 In th cs of bll brngs (on rod), th lmt l lod dpnd by msur of dynmc quvlnt rdl lod, th msur of mjor s of contct llps (), gomtry Of bll nd rollng wy, mtrls, tc. 79

5 4. NGUL CONTCT FULL CEMIC MTIX COMOSITES (CMCS) BEINGS Full Crmc ngulr Contct Bll Brngs r md ntrly of crmc mtrl nd r supror to common Stl ngulr Contct Brngs n mny wys. Crmc s th prfct mtrl for ny pplcton skng to chv hghr M s, rduc ovrll wght or for trmly hrsh nvronmnts whr hgh tmprturs nd corrosv substncs r prsnt. pplctons such s cryopumps, mdcl dvcs, smconductors, mchn tools, turbn flow mtrs, food procssng qupmnt, robotcs nd optcs. Crmc mtrls commonly usd for ngulr contct brngs r Slcon Ntrd (S3N4), Zrcon Od (ZrO), lumn Od (lo3) or Slcon Crbd (SC.) Bcus crmc s glss lk surfc t hs n trmly low coffcnt of frcton nd s dl for pplctons skng to rduc frcton. Crmc blls rqur lss lubrcnt nd hv grtr hrdnss thn stl blls whch wll contrbut to ncrsd brng lf. Thrml proprts r bttr thn stl blls rsultng n lss ht gnrton t hgh spds. Full Crmc brngs cn hv rtnr or full complmnt of blls, rtnr mtrls usd r EEk nd TFE. Full Crmc ngulr Contct Brngs cn contnu to oprt undr trmly hgh tmprturs nd r cpbl of oprtng up to 1800 Dg. F. Crmc s much lghtr thn stl nd mny brngs r 1/3 th wght of comprbl stl brng. Full crmc brngs r hghly corroson rsstnt nd wll stnd up to most common cds, thy wll not corrod n posur to wtr or slt wtr. nd fnlly full crmc brngs r non-conductv. Full Crmc ngulr Contct Brngs r dsgnd such tht thr s n ngl btwn th rcs nd th blls whn th brng s n oprton. n l lod psss n strght ln through th brng, whrs rdl lod tks n oblqu pth tht tnds to wnt to sprt th rcs lly. So th ngl of contct on th nnr rc s th sm s tht on th outr rc. Full Crmc ngulr Contct Brngs r typclly ssmbld wth thrust lod or prlod. Th prlod crts contct ngl btwn th nnr rc, th bll nd th outr rc. Th prlod cn b don whl mnufcturng th brng or t cn b don whn th brng s nsrtd nto n pplcton. Th contct ngl s msurd rltv to ln runnng prpndculr to th brng s. Full Crmc ngulr Contct Brngs r cpbl of wthstndng hvy thrust lods nd modrt rdl lods. Th lrgr th contct ngl (typclly n th rng 10 to 45 dgrs), th hghr th l lod supportd, but th lowr th rdl lod. In hgh spd pplctons, such s turbns, jt ngns, dntstry qupmnt, th cntrfugl forcs gnrtd by th blls wll chng th contct ngl t th nnr nd outr rc. Crm-mtr composts (CMCS) comprs crmc mtr rnforcd by rfrctory fbr, such s slcon crbd (SIC) fbr. CMCS offr low dnsty, hgh hrdnss nd supror thrml nd chmcl rsstnc, EFEENCES [1] I.Enscu, Gh. Cpturnu, D.Enscu ulmntedturunvrstttrnslvn 005 [] K.L.Johnson, Contct mchncs Cmbrdg Unvrsty rss 1985 [3] Boc Brngs Mntur Brngs For obotcs, Industry crtons 80