Univerzitet u Novom Sadu Tehnički fakultet „Mihajlo Pupin“ Zrenjanin
SEMINARSKI RAD PREDMET: TRANSPORTNE MAŠINE
Projektni zadatak
Tema: MOSTOVSKA DIZALICA
Profesor:
Student:
Zrenjanin, 2017
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SADRŽAJ • PROJEKTNI ZADATAK................. ZADATAK............................. ........................ ........................ ......................... ................. ....3 1. PRORAČUN I IZBOR OPREME MEHANIZMA ZA DIZANJE.......4 1.1 Polazni podaci....................................... podaci............................................................. ............................................... ...........................................4 ..................4 1.2 Donja koturača................................. koturača....................................................... ........................................ .................. ..............................4 1.2.1 Opšti podaci................................ podaci...................................................... ......................................... ................... ...............................4 1.2.2 Izbor užeta..................................... užeta........................................................... ...................................... ................ ...............................4 1.2.3 Izravnavajući Izravnavajući kotur........................................ kotur.............................................................. ................................. ........... ....................5 1.2.4 Glavne mere koturače................................ koturače......................................................... ............................ ... .............................5 1.3 Proračun doboša................................. doboša....................................................... ..................................... ............... ..............................6 1.3.1 Mere omotača doboša............................... doboša..................................................... ............................ ...... ..............................6 ..................................................................... ............................................. ............................7 ......7 1.3.2 Izbor ležajeva..... .............................................. 1.4 Elektromotor................ Elektromotor...................................... ............................................ .............................................. ..............................................7 ......................7 1.4.1 Merodavna snaga sn aga za izbor motora....................................... motora............................................................. ...............................7 .........7 1.4.2 Pogonske karakteristike motora...................................... motora............................................................... ....................................8 ...........8 1.5 Elastična spojnica................................ spojnica...................................................... .................................... .............. ...............................9 1.6 Kočnica sa hidrauličnim podizačem........................................ podizačem........................................ ..............................9 1.6.1 Mere dvopapu čne kočnice........................... kočnice................................................... ........................ ...............................9 1.6.2 Hidraulični podizač............................. podizač................................................... ................................ .......... ..............................10 .................................................................. ....................................10 ..............10 1.6.3 Provera kočnice................. kočnice................. ............................................ 1.7 Prenosnik snage................................................... snage......................................................................... ................................................ ...........................11 .11 1.8 Dinamika mehanizma za dizanje............................................ dizanje.................................................................. ..............................12 ........12
2.
PRORAČUN I IZBOR OPREME MEHANIZMA ZA KRETANJE ..................................................................... ..................................13 ...........13 ELEKTRIČNOG VITLA..............................................
2.1 Polazni podaci......................................... podaci............................................................... ............................................ .......................................13 .................13 2.2 Izbor vrste mehanizma za z a kretanje.................................................................. kretanje.......................................................................13 .....13 2.3 Izbor točka..................................... točka........................................................... .......................... .... .............................................13 2.4 Određivanje otpora i potrebne snage.................................................. snage........................................................... ......... .........14 2.5 Izbor elastične spojnice.................................. spojnice........................................................ ......................... ... ..............................16 2.6 Izbor vertikalnog reduktora......................................... reduktora.................................................................. .........................................16 ................16 2.7 Izbor zupčaste spojnice.................................... spojnice.......................................................... ........................ ..............................16 2.8 Proračun vremena ubrzanja................................... ubrzanja......................................................... .................................. ............ ..............17 2.9 Proračun vremena zaustavljanja.............................. zaustavljanja.............................................. ................ ..............................17
3.
PRORAČUN I IZBOR OPREME MEHANIZMA ZA KRETANJE DIZALICE..................................................................... ....................................................................... ..................................18 ..........18
3.1 Polazni podaci...................................... podaci............................................................ ................................................ ...........................................18 .................18 3.2 Izbor točkova.................................. točkova........................................................ ............................................ ............................................ ...........................19 .....19 3.3 Određivanje otpora, proračun proračun snage i izbor motora........................... motora............................................. .................. .20 .................................................................. ..........................................2 ....................22 2 3.4 Elastična spojnica............ ............................................ 3.5 Kočnica sa EHT – podizačem.............................. podizačem................................................. ................... ..............................22 3.6 Prenosnik snage (reduktor)................................................. (reduktor)....................................................................... ..................................23 ............23 3.7 Izbor zupčaste zupčaste i krute spojnice, dimenzionisanje dimenzionisanje vratila...................................... vratila...................................... 23 3.8 Dinamika mehanizma za kretanje............................................. kretanje................................................................... ............................24 ......24
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PROJEKTNI ZADATAK Projektovati Mostovsku dizalicu
opšte namene, koja učestvuje u tehnološkom
procesu proizvodnje proizvodnje u mašinskoj mašinskoj hali. Karakteristike dizalice su: - nosivost......................................... nosivost............................................................... ...............................m=20 .........m=20 (t) - brzina dizanja............................................... dizanja.............................................................Vd= ..............Vd= 16 (m/min) - brzina kretanja vitla....................................................Vv= vitla....................................................Vv= 32(m/min) - brzina kretanja dizalice..................... dizalice. .......................................... ..........................Vm=50 ....Vm=50 (m/min) - visina visi na dizanja.................... diz anja........................................... ............................................H .....................H=25 =25 (m) - raspon dizalice............................ dizalice.................................................. ...................................L=16(m) .............L=16(m)
Prema uslovima rada (režima) i zadatod srednjeg radnog ciklusa dizalice, sama dizalica-noseća konstrukcija i njeni pogonski mehanizmi su svrstani u treću pogonsku klasu (teški uslovi rada) prema JUS M.D1.020. Potrebno je uraditi sledeće: 1.Proračunati 1.Proračunati mehanizam za dizanje i izvršiti izbor standardne opreme, 2.Proračunati 2.Proračunati mehanizam za kretanje električnog vitla i izvršiti izbor standardne opreme 3.Proračunati 3.Proračunati mehanizam za kretanje dizalice i izvršiti izbor standardne opreme, 4.Dati sklopni crtež dizalice.
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1.
PRORAČUN I IZBOR OPREME MEHANIZMA ZA DIZANJE
1.1Polazni podaci - nosivost:................................... nosivost:................................... m = 20 (t) = 20000 (kg) - sila težine tereta: ....................... Q = m · g = 20 · 9,81 = 196,20 (KN) - brzina dizanja:.........................Vd = 10 (m/min) = 0,2666 (m/sec) - visina dizanja:............................H = 25 (m) - pogonska klasa:.............................. klasa:.............................. 3 (teška)
Pošto je dizalica opšte namene usvaja se jednokraka kuka, kao univerzalni uređaj za zahvatanje tereta u sklopu donje dvojne koturače. Oba kraja užeta namotavaju se na doboš, čiji je pogon ostvaren pomoću zupčaste spojnice specijalne specijalne izvedbe. Komponente mehanizma za dizanje su : kliznokolutni motor, elestična spojnica u kombinaciji sa dvopapučnom kočnicom sa hidrauličnim podizačem, horizontalni reduktor i doboš. 1.2Donja koturača
(t) i treću pogonsku klasu (teški uslovi rada) usvojena je standardna koturača (redni broj 9 iz tabele I) sa dva kotura, koja se u mehanizmu za dizanje koristi kao dvojna koturača. Za nosivost m = 20
1.2.1 Opšti podaci
Prenosni odnos koturače: i n2142η 2 10,98 Koeficijent iskorišćenja: η ik1 η 210,988 0,99 Broj krakova užeta: n = 4
gde je: ηo = 0,98 – stepen – stepen iskorišćenja jednog kotura sa kotrljajućim ležajevima 1.2.2 Izbor užeta Maksimalna sila u užetu:
196,2909 49,545 Fx n ⋅Qη 4⋅0, 45 KN KN Sila kidanja u užetu:
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za 3 pogonsku klasu
Na osnovu sile kidanja usvaja se desnohodo desnohodo unakrsno predeno predeno uže: d 27 (6x37 = 222) Tip B – DIN DIN 655
sa jačinom kidanja jedne žice σM = 1570 (N/mm 2) (160 kp/cm2) čija je računska sila kidanja S o = 402 (KN) ˃ S = 312,136 (KN) Stvarni stepen sigurnosti:
S 49,402545 8,11 υ Fx
Karakteristike užeta:
- prečnik žice δ = 1,2 (mm) - površina poprećnog poprećnog preseka F = 251,1 (mm2) - težina dužnog metra q = 2,38 (kg/m)
Ukupna težina užeta ( 80 m dužine) G u = 190,4 kg 1.2.3 Izravnavajući Izravnavajući kotur
Prečnik izravnavajućeg kotura:
D (Dd) ⋅du12⋅27324 mm
Odnos (D/d)ik = 12 za treću tr eću (3) pogonsku klasu prema JUS M.D1.070. Usvaja se standardni kotur. D = 320 (mm) = 90 (kg). Ukupna težina izravnavajućeg kotura: G ik = 1.2.4Glavne mere koturača
Glavne mere koturača su usvojene iz standarda (Tabela I – dodatak) za koturaču 9. Prečnik kotura:
D (Dd) ⋅ du 22 ⋅ 27 594 mm odnos(Dd) 22 zaza treć trećuu 3 pogonsku klasuasu prema JUS M.D1. M. D1.070
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1.3
Proračun doboša
Konstrukcija doboša je zavarena sa cilindričnim omotačem na kome su narezani žljebovi (levi i desni navoj). Krajevi užeta za omotač doboša su vezani pomoću pločica i zavrtnjeva. Za jedan kraj užeta užeta predviđene su su tri veze. Obrtni moment sa izlaznog vratila reduktora na doboš se prenosi pomoć u izvedene zupčaste veze. Omotač doboša je od Č.0361, a osovine od Č.1530. 1.3.1 Mere omotača doboša - Nazivni prečnik doboša
D (Dd) ⋅ du 22 ⋅ 27 594 mm
Usvaja se standardni prečnik D = 560 (mm)
- Dimenzije žljebova:
Za prečnik užeta d = 27 (mm) usvojene su sledeće dimenzije žljebova: S = 28 (mm) r = 14 (mm) a1 = 3,5 (mm) - Dužina doboša: Ld = 2b + 2Lnar + Lq (mm) b = 62 (mm)
Ukupan broj žljebova:
z4+ iπ ⋅⋅ DH 4 + 3,12⋅25 4⋅0,63 29, 2 630
Lnar = z · S = 30 ·30 = 900 (mm) Lq = 300 (mm) Ld = 2 · 62 + 2 · 930 + 300 = 2224 (mm) Odnos Ld/Dd = 2224/560 = 3,97 ˂ 4 - Debljina omotača doboša:
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Dozvoljeni napon za Č.0361 iznosi σ doz = 12,5 (KN/cm2) 1.3.2 Izbor ležajeva -Broj obrtaja doboša:
− − n πi ⋅⋅DV 3,12⋅10 10, 1 05 mi n 0, 1 68 sec 4⋅0,63 - Sile reakcije u osloncima osovina doboša
F 16551 49,5451015+755 87,694694 KN KN F 16551 49,54545640+900 640+900 76,299299 KN KN
U osloncu A je usvojen dvoredni samoudesivi s amoudesivi bačvasti ležaj tipa
22318 E „SKF“ Dimenzije: d = 90 (mm); D = 190 (mm); B = 64 (mm) Nosivost: C = 535 (KN) U osloncu B je usvojen dvoredni samoudesivi bačvasti ležaj tipa
22224 E „SKF“ Dimenzije: d = 120 (mm); D = 215 (mm); B = 58 (mm) ( mm) Nosivost: C = 552 (KN) 1.4Elektromotor 1.4.1 Merodavna snaga za izbor motora - Snaga dizanja:
Q ⋅ V 245250⋅ 0 , 1 666 P 1000⋅η 1000⋅0, 1000⋅0,90 45,4 KW gde je:
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z = ( zn + zk ) ) · c = gde je:
4 + 2 ÷ 4 ⋅20120÷160 uklj/h
zn = 4 – normalni – normalni broj uključenja motora mehanizma za dizanje u jednog radnog ciklusa dizalice
toku
zk = = 2 ÷ 4 – korektivni – korektivni broj uključenja motora - Potrebna snaga motora sa standardnom intermitencom ED 40%
P P√ EDε 45,4⋅ 44,44,4044 47,8585 KW KW - Izbor elektromotora:
Iz odgovarajućeg kataloga za vrstu pogona S 4, standardnu intermitencu ED 40% i broj uključenja z = 150 (uklj/h) usvaja se: Kliznokolutni dizalični motor tipa: ZPD – 280 S – 6 6 – „SEVER“ Subotica – „SEVER“ – Subotica Nominalna snaga Pn = 50 (KW); broj obrtaja n 1 = 982 (m -1) = 16,366 sec -1; moment inercije rotora motora Ir = 2,82 (kg/m 2); prevrtni faktor preopterećenja ψ m = Mm/Mn=45 Težina elektromotora: G m = 780 kg. 1.4.2 Pogonske karakteristike motora - Ugaona brzina pogonskog vratila
− ω π30⋅ n 3,14⋅982 103 sec 30 M 9550 P 9550 50 48486,6,25 Nm Nm - Nominalni moment motora
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1.5 Elastična spojnica
- Moment tereta pri ustaljenom kretanju tereta
M 2 ⋅Qi⋅⋅Di⋅ η 9550 nP 9550 45,9824 44441,1,52 Nm Nm
Pošto se deo elastične spojnice koristi kao kočioni doboš dvopapučne kočnice iz
tabele 15 za nazivnu snagu motora P n = 50 KW pri 40 % ED i broj obrtaja motora n1 = 982 min-1 usvaja se prečnik kočionog doboša D k = = 400 mm.
Na osnovu izloženog usvaja usvaja se elastična spojnica: Ø 400 JUS M.C1.516 koja može da prenese obrtni moment M
= 1250 (Nm)
- širina kočionog doboša L s = 150 (mm) - težina elastične spojnice Ges = 107 (kg) 1.6Kočnica sa hidrauličnim podizačem 1.6.1 Mere dvopapučne kočnice -Prečnik i širina kočionog doboša Dk = = Des = 400 (mm);
ls = 150 (mm)
Obloge papuča su od presovanog azbesta sa provučenim mesinganim žicama, = 0,4. čiji je koeficijent trenja μ k = (5÷10) = 150 – 10 10 = 140 mm Obuhvatni ugao obloga je β = 70 0, a širina B = ls – (5÷10) - Površina obloga:
π ⋅ D ⋅ β π⋅40⋅70 A 360 ⋅ B 360 ⋅ 14 342,08 cmcm
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i ba ⋅ dc 500200 ⋅ 25260 10,5
1.6.2 Hidraulični podizač
- Moment kočenja kočnice Mk = υ · M ·η2 = 2,5 · 441,52 · 0,9 2 = 894,08 (Nm) gde je:
υ = 2,5 – usvojena – usvojena vrednost stepena sigurnosti kočenja kočnice -Sila kočenja
F i ⋅ ηM⋅ μ ⋅ D 10,5⋅0,894,93⋅0,08 4⋅0,4 572,255 N gde je: = 0,93 – stepen ηk = – stepen korisnosti polužja kočnice
Na osnovu sile kočenja usvaja usvaja se hidraulični hidraulični podizač: EHT – 375 375 F – „Elektrokovina“ Maribor – „Elektrokovina“ – Maribor
čija je: - povratna kočiona = 700 (N) kočiona opruga jačine F k = - sila podizanja F p = 750 (N) - visina u neukočenom stanju H = 480 (mm) - hod podizanja h p = 50 (mm) - iskorišćena vrednost hoda h = 50 – (10÷20) ≈ 30 (mm) - visina podizača u ukočenom stanju H k = = H – (10÷20) (10÷20) = 480 -20 = 460 (mm) - težina podizača G = 30 - ukupna težina kočnice G k = = 91,6 (kg) 1.6.3Provera kočnice Stepen sigurnosti
Normalna sila na na kočionom doboš
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Provera kočionih obloga - Specifični pritisak
5 N P AF 6835, 20( granicama dozvol dozvoljenognog pritiskaka 342,08 cm) , što je u grani - Kritična brzina kočenja na obodu kočionog doboša
gde je:
V π ⋅ D60 ⋅ n ⋅ K 3,14⋅0,604⋅982 1,122,62 ms
K = 1,1 ÷ 1,2 – stepen stepen sigurnosti. - specifična snaga kočenja kočnice
pV 20⋅22,62452,4(cmNm ⋅ s) < pVd 500(cmNm ⋅ s)
Na osnovu ovog približnog (toplotnog) proračuna, obloge papuča
zadovoljavaju. 1.7Prenosnik snage (reduktor) - Prenosni odnos reduktora
i nn 10,982105 97,18
- Izbor standardnog reduktora za treću pogonsku klasu (3): - ulazni broj obrtaja n 1 = 982 (min -1), - prenosni odnos i r = = 97,18, i - ulazna snaga P n = 50 (KW) Usvaja se standardni trostepeni horizontalni reduktor:
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V π ⋅ Di ⋅ n 3,14⋅0,623⋅10,911 10,797 mimn W V VV ⋅100% 10,7109710 ⋅100+7,97%
- odstupanje brzine:
Odstupanje brzine je u granicama granicama dozvoljenog ± 8% prema JUS M. D1. 023. 023. 1.8Dinamika mehanizma za dizanje
Elementi kretanja pri kočenju spuštanja tereta kočenja ,J ⋅ ωVreme 3⋅103 63 0,591 sec ≈0,6 sec t M M , 1093,4,628357, J, redukovani redukovani moment inercije pri kočenju 0, 1 666 ,J 1,5⋅I + m (ωV ) ⋅η1,5⋅2,82+25⋅10 ⋅η1, 5 ⋅2, 8 2+25⋅10 ( ) ⋅0, 9 4, 2 3 kgm 103 M, moment tereta na prvom vratilu u periodu kočenja M, 2Q⋅ i⋅D⋅i ⋅ηM⋅η 441,52⋅0,9 357,633NmNm -
gde je: -
gde je:
-
Mk = = 1093,68 (Nm) – moment – moment kočenja kočnice
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2.
PRORAČUN I IZBOR OPREME MEHANIZMA ZA KRETANJE ELEKTRIČNOG VITLA 2.1 Polazni podaci - nosivost:....................................m nosivost:....................................m = 20 (t) = 20000 (kg) - sila težine tereta:........................ tereta:........................ Q = m · g = 20 · 9,81 = 196,20 (KN) - brzina kretanja vitla:................Vv = 32 (m/min) = 0,5333 (m/sec) - pogonska klasa:................................... 3 (teška)
Ukupna približna masa: Mv = (0,3 ÷ 0,4)m ± 10 % = (0,3 ÷ 0,4) · 25 ± 10 % ≈ 9 (t) 2.2Izbor vrste mehanizma za kretanje Kako je mehanizam namenjen srednjoj nosivosti dizalice to je pogodno usvojiti
centralni pogon sa dva slobodna i dva pogonska točka. Sastavni podsklopovi mehanizma za kretanje električnog vitla su sledeći: 1. Elektromotor (KZK) 2. Elastična spojnica (JUS M.C1.515) 3. Vertikalni reduktor 4. Pogonsko vratilo prenosa 5. Zupčasta spojnica 6. Pogonski točak (JUS M.D1.110)
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Iz T. 18. K 1 = 1,0
Broj obrtaja točka:
403,14 40,42 min− n DV⋅ π 0,315⋅15⋅3,
Iz T. 19. K 2 = 0,82 – za – za broj obrtaja točka prethodno pr ethodno izračunat Iz T. 20. K 1 = 0,9
Provera prečnika točka:
71, 1 2 D P ⋅ K ⋅ KF⋅ b2⋅r b2⋅r 0,75⋅0,82⋅0,9⋅⋅ 5, 5 2⋅0, 5 D 2,49cm < D 315mm Usvojen:
Pogonski točak Ø315 JUS M.D1.110 (kom.2) Slobodni točak Ø315 JUS M.D1.111 (kom.2) Težina točka G = 1,5 (KN) Potrebne dimenzije: l = 285 (mm), b2 = 379 (mm) 2.4
Određivanje otpora i potrebne snage
Otpori ustaljenog kretanja: f = 0,05 (cm)
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20+910⋅ 10⋅2,5⋅⋅0,0,95333 +1,5⋅0,05⋅ 10100, ⋅2,55 ⋅0,054,75 KW
Ir = = 0,05 (kgm 2) – pretpostavljena pretpostavljena vrednost momenta inercije rotora motora = 2 Ukupna snaga potrebna za izbor motora se izračunava, pretpostavljajući: ψ sr =
7 5 P Pψ+P 2,592+4, 2 3,671 KW
Usvojen elektromotor KZK – 132 132 Mk – 6 Subotica) T. XI, – 6 („Sever“ – Subotica) sa karakteristikama: Pn = 4 (KW), n1 = 970 (min-1) GD2 = 0,1784 (Kpm 2) Ir = 1/4·GD2 = 0,0446 (Kgm 2) = Mm/Mn = 2,18 Ψk = Ψ p = Mp/Mn = 2,6
Moment kočenja u motoru: Mkmax = 0,1 (KNm) S obzirom na veličinu kočionog momenta vađenjem polovine opruga prepolovljuje se efektivni kočioni moment. Ovo je iz razloga što se za brzine kretanja manje od 25 (m/min) ne mora ugrađivati kočnica :
M 12 ⋅ Mx 0,05KNm 50Nm
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2.5
Izbor elastične spojnice:
Mn = 39,38 (Nm). Na osnovu nazivnog momenta motora usvaja se elastična spojnica Ø160 (JUS M.C1.515). 2.6 Izbor vertikalnog reduktora Potreban prenosni odnos reduktora:
i nn 40,97042 23,99
Za treću pogonsku klasu (3) i broj obrtaja (n 1≈950 (min-1), a potrebnu snagu i prenosni odnos (iR ) usvajam: V2.32/VII sa karakteristikama: Pmax = 5,6 (KW), i R = = 22,5 Konstruktivne mere: (G + 2L) = 300 300 + 2 · 90 = 480; E = 320; 320; (G1 + l) = 160 + 60 = 220 (mm) d = 28 (mm); D = 55 (mm); = 625 (mm)
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zupčasta spojnica: Br.01 sa M tmax = 500 (Nm). Iz konstruktivnih razloga zbog prečnika izlaznog vratila reduktora D = 55 mm, usvaja se zupčasta Zadovoljava
spojnica Br.03. Konstruktivne mere:
Prečnik rukavca vratila........................................... vratila...............................................d ....d 4 = 50 ÷ 63 (mm); Spoljašnji prečnik............................................... prečnik........................................................D .........D = 200 (mm); D1=145 (mm); D2=100 (mm); Dužina................................. Dužina....................................................... ..........................................l ....................l = 166 (mm ); Masa spojnice............................................................... spojnice...............................................................G G = 16 (kg); 2.8
Proračun vremena ubrzanja
Redukovani moment inercije svih masa na prvom vratilu:
V J 1,5Ir+ m + m (ω) ⋅ η1
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0, 5 333 1,5⋅0,0446+ 20+9 ⋅ 10 ( 101,5 ) ⋅0,91,387 kgm
Moment usled statičkih otpora redukovan na vratilo elektromotora:
1, 4 ⋅0, 3 15 ,M ∗ 2Fw∗⋅ i⋅ D⋅ η 2⋅22, 88 NmNm 5⋅0,9 10,888 Iz osnovne -
ravnotežne jednačine ravnotežne jednačine momenata momenata na prvom vratilu: vratilu:
M M, M,∗ J, ⋅ ωt M,∗ gde je:
Mk = = 50 (Nm) – moment – moment kočenja motora
Sledi vreme zaustavljanja:
J, ⋅ ω 1,387⋅101,5 2,312
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6. Krutih spojnica 7. Vratila sa ležajevima 8. Dva kretna točka 3.3 Izbor točkova - Šeme opterećenja:
Pretpostavlja se rastojanje e = 2 (m). - Pritisci po točkovima:
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K 0,9494 za n πV⋅D 3,1504⋅0,5 50,929 min− iz tabele 19 K 3 = 0,9 za treću pogonsku klasu iz tabele 20
D 0,75⋅0,94⋅0,166,90736, 5 2⋅0, 6
D = 49,384 (cm) ˂ D T = 50 (cm)
Usvojena su dva kretna točka Ø500 JUS M.D1.110 i dva slobodna slobodna točka Ø500 JUS M.D1.111 Težina točka G = 391 (kg) 3.4 Određivanje otpora, proračun snage i izbor motora - Otpor ustaljenog kretanja
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η = 0,9 – stepen – stepen iskorišćenja prenosa
- Ukupna snaga:
6 42 P Pψ+P 8,817+30, 1,8 21,921 KW
gde je: = 1,8 – pretpostavljen ψsr = pretpostavljen srednji srednji faktor preopterećenja. preopterećenja. - Relativno trajanje uključenja:
= ∑ 29+28 = ε% T t ⋅100% 29+28 180 ⋅100%31,66% - Broj uključenja motora na čas:
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M 9550 nP 9550 96528 277,09 Nm - Moment upuštanja (zaletanja) motora: Mu = ψsr · · Mn = 1,8 · 277,09 = 498,762 (Nm)
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..........................................G = 20 (kg) Težina podizača........ podizača..................................................G Ukupna težina kočnice............................. kočnice.......................................G ..........G k = 87 (kg) - Stvarni moment kočenja kočnice: Mk = = Fk · · ik ·ηk ·μk · · Dk = = 280 · 10,18 · 0,93 · 0,4 · 0,2 = 212,07 (Nm) 3.7 Prenosnik snage (reduktor) - Prenosni odnos reduktora:
965
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3,121
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= V 1 1 1, 3 33 J 1,5⋅I +m( ) ⋅ 1, 5 ⋅1, 0 7+57, 8 ⋅10 ( ) ⋅ ω η 101, 0 5 0,9 = J 12,788 kgm w ⋅ D 9550 P 9550 8,817 87,25 M F2⋅i⋅η n 965 5 NmNm Mu = 498,762 (Nm)
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6. Kruta spojnica..............................6x60 spojnica..............................6x60 360 (kg) 7. Vratilo..........................................8x67 Vratilo..........................................8x67,8 ,8 542,4 (kg) 8. Kretni točak........ .........................2x391782 (kg) g) 2765,1 (kg) ≈ 2765 (k g)
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