Square tube VS lub raj raj, qhov twg zoo dua?
Qhov kev ua tau zoo sib txawv ntawmlub cevthiabcev squarenyob rau hauv engineering daim ntaub ntawv yuav tsum tau muab kev txheeb xyuas los ntawm ntau yam mechanical foundations xws li lub zog, nruj, stability, thiab bearing muaj peev xwm.
1. Lub zog (khoov thiab torsion kuj)
Bending zog:
Rectangular raj: Thaum raug khoov load raws qhov ntev sab kev taw qhia (qhov siab qhov siab), ntu inertia lub sij hawm loj dua, thiab khoov kuj zoo dua li cov square raj.
Piv txwv li, lub zog dabtsi yog khoov ntawm 100 × 50mm square raj nyob rau hauv qhov ntev sab kev taw qhia yog siab dua li ntawm 75 × 75mm square raj.
Square raj: Lub sij hawm inertia yog tib yam nyob rau hauv tag nrho cov lus qhia, thiab kev khoov kev ua tau zoo yog symmetrical, tab sis nws cov nqi feem ntau yog me dua li ntawm qhov ntev ntawm sab kev taw qhia ntawm lub raj plaub nyob rau hauv tib lub cheeb tsam cross-sectional.
Xaus: Yog tias cov kev taw qhia ntawm kev thauj khoom yog qhov tseeb (xws li cov qauv kab teeb), lub raj duab plaub zoo dua; Yog hais tias lub load kev taw qhia yog txawv, lub square tube yog ntau balanced.
Lub zog torsion:
Lub torsion tas li ntawm lub raj square yog siab dua, lub torsion kev nyuaj siab faib yog ntau yam, thiab torsion kuj yog zoo dua li ntawm lub kaum sab xis raj. Piv txwv li, qhov torsion tsis kam ntawm 75 × 75mm square tube yog qhov muaj zog dua li ntawm 100 × 50mm lub raj raj.
Xaus: Thaum lub torsional load yog qhov tseem ceeb (xws li cov ncej sib kis), cov raj square zoo dua.
2. Striffness (anti-deformation peev xwm)
Bending hardness:
Lub zog yog proportional rau lub caij ntawm inertia. Rectangular raj muaj qhov nruj dua nyob rau hauv qhov ntev ntawm kev taw qhia, uas yog tsim rau cov xwm txheej uas yuav tsum tau tiv thaiv unidirectional deflection (xws li choj kab teeb).
Square raj muaj symmetrical bidirectional txhav thiab yog haum rau multidirectional loads (xws li kab).
Xaus: Cov kev xav tau nruj yog nyob ntawm qhov kev taw qhia load. Xaiv cov raj duab plaub rau unidirectional loads; xaiv square raj rau bidirectional loads.
3. Stability (buckling kuj)
Local buckling:
Rectangular hlab feem ntau muaj qhov dav dav-rau-thickness piv, thiab nyias-walled qhov chaw muaj ntau dua rau hauv zos buckling, tshwj xeeb tshaj yog nyob rau hauv compression los yog shear loads.
Square tubes muaj kev ruaj ntseg hauv zos zoo dua vim lawv qhov sib txawv ntawm qhov sib txawv.
Zuag qhia tag nrho buckling (Euler buckling):
Buckling load muaj feem xyuam rau qhov tsawg kawg nkaus lub vojvoog ntawm gyration ntawm tus ntoo khaub lig-section. Lub vojvoog ntawm gyration ntawm square tubes yog tib yam nyob rau hauv tag nrho cov lus qhia, thaum lub vojvoog ntawm gyration ntawm lub voj voos nyob rau hauv lub luv sab kev taw qhia yog me me, ua rau lawv ntau buckling.
Cov ntsiab lus: cov raj square yog nyiam rau cov tswv cuab compressive (xws li ncej); yog hais tias qhov ntev sab kev taw qhia ntawm lub raj plaub yog constrained, nws muaj peev xwm yuav compensated los ntawm tsim.
4. Cov kabmob muaj peev xwm (axial thiab ua ke loads)
Axial compression:
Cov kabmob muaj peev xwm muaj feem cuam tshuam rau thaj chaw hla ntu thiab qhov sib luag. Nyob rau hauv tib lub cheeb tsam cross-sectional, square tubes muaj peev xwm ua tau ntau dua vim lawv txoj kev loj dua.
Combined load (combined compression thiab dabtsi yog khoov):
Rectangular tubes tuaj yeem ua kom zoo dua ntawm qhov kev ua kom zoo dua qub thaum lub sijhawm khoov cov kev taw qhia meej (xws li ntsug load rau sab ntev); square raj yog tsim rau bidirectional dabtsi yog khoov lub sij hawm.
5. Lwm yam
Kev siv cov khoom siv:
Rectangular tubes muaj txiaj ntsig zoo thiab txuag cov ntaub ntawv thaum raug unidirectional dabtsi yog khoov; square tubes yog kev lag luam ntau dua nyob rau hauv ntau txoj kev thauj khoom.
Kev sib txuas yooj yim:
Vim lub symmetry ntawm square tubes, node kev sib txuas (xws li vuam thiab bolts) yog yooj yim dua; cov raj plaub yuav tsum xav txog kev coj ua.
Daim ntawv thov scenarios:
Rectangular raj: lub tsev kab teeb, crane caj npab, tsheb chassis (clear load kev taw qhia).
Square raj: lub tsev kab, qhov chaw trusses, mechanical thav duab (multi-directional loads).
Post lub sij hawm: May-28-2025
