KINETIC AND STATIC ANALYSIS AT UNLOADED RUNNING ON MECHANISMS OF PARALLEL GANG SHEARS TYPE ASSIGNED FOR CUTTING THE METALLURGICAL PRODUCTS

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1 nns of the Unversty of Petroşn echnc ngneerng 9 (7) KINTI N STTI NLYSIS T UNLO UNNIN ON HNISS O PLLL N SHS TYP SSIN O UTTIN TH TLLUIL POUTS IN UIUL HIN 1 ; VSIL ZI ; TOO VSIU bstrct: In ths study s presented the knetc nd sttc nyss of sher type echnss for cuttng eturgc products t the trn of the se-fnshed stee products ong No. 1 S..1 of S.. ITTL STLL S.. HUNO n condtons of dsregrdng the frctons exstent n the knetc coupngs. Keywords: echns forces nd oents of nert forces recton 1. INTOUTION The knetc nd sttc nyss s to deterne the forces tht ct n the knetc eeents of the.e. vrton of these forces durng knetc cyce usuy represented by vrton of the nge of sght of the edng eeent. These cn be forces nd oents of nert forces frcton forces or recton fro the knetc coupngs. Knowedge of these forces nd oents s necessry n order to sze the knetc eeents of echnss. The knetc schee for the echns of pre gng shers ssgned to cut eturgc products s shown n gure 1 nd conssts n: hnd-hod 1 short drvng rod upper r ong drvng rod ower r 5 nd upper sde. Ths type of echns works n phses.e.: n the frst phse s owered the superor cutter up to the surfce of the stee se-fnshed product nd then stopped nd ocked n ths 1 Ph. ng. t Potehnc Unversty of Tsor ngneerng cuty of Hunedor on Prof. ng. Ph. t Unversty of Petrosn. ngneerng cuty of Petrosn. on ssoc. Prof. ng. Ph. t Potehnc Unversty of Tsor ngneerng cuty of Hunedor on

2 udu-erghn. Zfr V. Vsu T. poston oent when the nferor cutter whch perfors the cuttng of stee sefnshed product strts to ft. fter cuttng hs done the nferor cutter coes bck to the nt poston nd then the upper r s fted n the nt poston. these oveents re coordnted by the crnkshft.e. O hndhod 1 nd re ccopshed t stroke of of the hndhod. ro ths reson the knetc nyss nd knetc nd sttc nyss s we for ths type of echns w be perfored on phses of oveent. Knetc nyss of the echns s perfored on knetc groups strtng wth the group contnng the foower eeent (t unoded runnng ths s the superor cutter) nd w be copeted by knetc nd sttc nyss of the edng eeent nd w coprse the foowng stges of ccuus: - -eternton of the poston for the grvty center of coponent eeents; 1 5 g. 1. Knetc Schee of the 8tf sher - -eternton of cceertons for the grvty centers of coponent eeents; - -eternton of forces nd oents of nert forces for eeents.e. settng up the drectons; - -Presentton of the odng schee for the knetc group contnng the representton of forces tht od the eeents; - -eternton of rectons n the knetc coupngs. TINTION O TH POSITION O VITY NTS O TI LNTS g.. rvty centre of the eeent () (short drvng rod) grvty center sttc nert oents) re presented n []. In order to deterne the postons of grvty centers for coponent knetc eeents these re represented t sce n uto nd consderng tht they hve n pproxte constnt thckness usng the regon odeng syste cn be obtned the desred nforton [1]. Inforton obtned by the regon odeng syste (pereter re

3 Knetc nd Sttc nyss t Unoded unnng on echnss of... 7 ue to the fct tht we re nterested ony n the poston of grvty center we w not present nyore the entre st of nforton for other prts but ony the poston of grvty center whch w be drwn drecty on the technc drwng. g.. rvty centre of the eeent () (upper r) g.. rvty centre of the eeent() (ong drvng rod) g. 5. rvty centre of the eeent (). TINTION O LTIONS O VITY NTS N THI ITIONS LT TO HOIZONTL ITION Knowedge of cceertons for the grvty centers s necessry to deterne the nert forces whch ct on eeents. cceerton of the grvty center for the superor r (eeent ) s deterned ccordng to the poygon of cceertons shown n gure. ccordng to gure cn be wrtten the foowng retons whch deterne the vue of cceerton for the grvty center.e. drecton reted to horzont:

4 udu-erghn. Zfr V. Vsu T. 8 g.. cceerton of grvty centre of the eeent () ε ω (1) cceerton of center t n reted to pont ; cos s cceerton of the grvty center.. LULUS O INTI OS N ONTS O INTI OS WHIH T ON TH TI LNTS Inert forces whch ct n echnss cn be reduced t torson consstng n n nert force hvng the ppcton pont n the grvty center of eeents nd the oent of nert force. Ther vues re deterned ccordng to the retons () (n condtons of knowedge the weghts of eeents nd ner nd ngur cceertons ccuted wthn the knetc nyss of echns) ε ε ε () t n p s

5 Knetc nd Sttc nyss t Unoded unnng on echnss of TINTION O TIONS IN KINTI OUPLINS O TIS WITHOUT TKIN INTO OUNT TH ITION O KINTI OUPLINS eternton of rectons n coupngs s perfored hvng s bse the odng schee presented n gure 7. Wth the nottons of gure 7 nd n condtons when re known the weghts of coponent eeents (thus re known the weght forces too) cn be wrtten the foowng equtons of equbru: ( 5Kg; 155Kg; 5Kg; Kg). ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) y -x x ' -y x x x cosγ y y y 1 snγ x x x x cosγ y y y y snγ x x x cosγ y y y snγ x x y y x snϕ y cosϕ cosϕ sn( ϕ γ ) ( ) x ' snϕ y ' cosϕ cosϕ sn( γ ϕ ) x '' snϕ y '' cosϕ ( ) x cos( 7 ϕ ) y sn( 7 ϕ ) sn( 7 ϕ ) sn( ϕ 18 γ ) ( ) y -x x y x -y y x g. 7. Lodng Schee of trd y '' -x -y y x y () The set of equtons s ner one wth 1 equtons nd 1 unknown

6 7 udu-erghn. Zfr V. Vsu T. ( y) nd hs been soved n x y x y x y x y x y th nd wth soutons obtned cn be ccuted the vues of rectons n coupngs : x x y y x x y y x y () rphc representton of recton vrton n coupng wthout frcton dependng on vrton of hndhod nge ϕ 1 s shown n gure [N] x f 1[grd] g 8. Vrton of recton n coupng wthout frcton. ONLUSIONS sed on resuts obtned presented by ths study cn be nferred the foowng concusons: - Inert forces nd oents of nert forces whch ct on knetc eeents tht copose echns hve vues retve hgh due to the sze of 8tf sher ther vrtons keep the vrton ode of cceertons of grvty centers of eeents nd of ngur cceertons of coponent knetc eeents s we. - Not tkng nto ccount frctons the rectons n knetc coupngs nd oent of equbru on the edng eeent hve xu vues of order 1 5 [N] nd 1 [N]. These vues re for operton t unoded runnng of echns for oded runnng the vues of recton beng uch hgher they depend on the secton of the ter whch foows to be cut nd not t est on the teperture of ths ter. NS [1]. urchrd. ş.. Secrete uto 1 dtur Teor ucureşt 1998; []. udu-erghn. nz cnetcă ş cnetosttcă ecnseor tp forfecă pentru debtt produse eturgce refert doctort nr..