A ntsia liaj qhov roojyog ib hom fastener uas tuaj yeem muab faib ua cov bolts zoo tib yam thiab muaj zog bolts raws li lawv qhov sib txawv tensile lub zog. Cov ntaub ntawv sib txawv ntawm cov ntsia liaj qhov rooj kuj tuaj yeem cuam tshuam rau kev ua haujlwm thiab ntau yam ntawm kev siv bolts. Tam sim no cia peb saib cov ntaub ntawv txheeb xyuas ntawm bolts rau koj siv.
Ordinary ntsia liaj qhov roojkhoom
Cov bolts ib txwm muab faib ua ob theem: qib 8.8 hauv qab thiab qib 8.8 saum toj no. Thaum lub ntsia liaj qhov rooj belongs rau qib 8.8 lossis qis dua, nws lub zog tensile nominal yuav tsum ncav cuag qib 400 MPa, thiab lub zog tawm los yuav tsum yog 0.6. Qhov nominal yield zog yuav tsum mus txog qib 400 × 0.6=240 MPa. Muaj ntau ntau yam khoom siv rau bolts zoo tib yam, thiab cov ntaub ntawv hauv qab no tuaj yeem txiav txim siab thaum xaiv:
-1008K
-1010
-1015K
-1032
-1035
-1040
-CH38F
-1039
-Lwm cov ntaub ntawv thiab cov khoom
Cov ntaub ntawv saum toj no yog tag nrho cov ntaub ntawv tsis sib nqus, thiab lawv lub zog tensile thiab lub zog tawm los kuj ua tau raws li qhov yuav tsum tau ua. Txawm li cas los xij, nws yuav tsum raug sau tseg tias 304M muaj cov hlau nplaum me me (ib puag ncig 1.6u-2.0u) tom qab ua haujlwm txias, 304HC muaj hlau nplaum (ib puag ncig 1.01u-1.6u), thiab cov hlau nplaum ntawm 316 cov khoom tom qab ua haujlwm txias yog tsawg dua 1.01u.
Siab zog boltkhoom
Lub zog muaj zog bolts xav tau cov ntaub ntawv nrog lub zog tensile siab dua kom ua tau raws li qhov yuav tsum tau ua kom nruj dua. Kev kho quenching muaj qhov cuam tshuam loj rau qhov siab tshaj plaws tensile lub zog ntawm cov ntaub ntawv. Tom qab 40Cr quenching kev kho mob, nws yog feem ntau nyuaj kom ua tau raws li cov khoom yuav tsum tau ntawm 10.9S qib high-strength bolts. Yog li ntawd, nyob rau hauv cov ntaub ntawv uas qhov kev soj ntsuam tsis nruj heev, lub siab tshaj plaws tensile lub zog ntawm cov khoom yuav txiav txim los ntawm lub nto hardness tom qab quenching kev kho mob. Nyob rau hauv cov kev kub ntxhov siab, lub zog siab bolts ntawm cov khoom sib txawv kuj yuav muaj qhov sib txawv ncua kev ua haujlwm tawg.
Kev xaiv thiab siv cov bolts muaj zog kuj yuav tsum tau txiav txim siab raws li cov xwm txheej tshwj xeeb. 40 Crmuaj zog bolts are mainly used in bolted ball joint grid structures, with a design strength generally of 390MPa (d>=30mm) los yog 430MPa (d<30mm), and there is no high pre tensile stress during use. When used in situations where high pre tension is to be applied, it is necessary to pay attention to and ensure its delayed fracture performance. The delayed fracture performance of 20MnTiB high-strength bolts is better than that of 40B.
Raws li tus qauv GB/T1231-91, nws raug nquahu kom siv 20MnTiB cov ntaub ntawv (cov lus qhia tshwj xeeb<=M24) and 35VB material (applicable specification<=M30) for 10.9S bolts. In quenching treatment, large-diameter high-strength bolts are not easily quenched, so in general, high-strength bolts with excessively large diameters should not be used. If they are to be used, their working stress should be reduced.
Cov ntsiab lus
Cov saum toj no yog cov ntsiab lus tseem ceeb ntawm kev txheeb xyuas cov khoom siv bolt. Txawm hais tias nws yog cov bolts zoo tib yam lossis cov bolts muaj zog, cov khoom sib txawv yuav muaj qee yam cuam tshuam rau lawv qhov kev ua tau zoo thiab kev siv ntau yam. Yog li ntawd, thaum xaiv thiab siv bolts, nws yog ib qho tsim nyog los txiav txim siab cov khoom siv ntsia liaj qhov rooj raws li cov kev cai tshwj xeeb.
