Lub elasticity txuam ntawm cov ntaub ntawv taug qab yog muaj feem xyuam rau qhov smoothness ntawm txoj kev khiav
Dab tsi yog qhov sib txawv hauv cov qauv elastic thiab kev laus ua haujlwm ntawm peb cov khoom siv feem ntau siv rau kev tsheb ciav hlau: roj hmab, EVA, thiab polyurethane?
Peb cov ntaub ntawv uas feem ntau siv rau kev tsheb ciav hlau taug kev pads- roj hmab, EVA, thiab polyurethane- pom muaj qhov sib txawv tseem ceeb hauv cov qauv elastic thiab kev laus. Hais txog elastic modulus, cov ntaub qhwv roj hmab muaj qhov elastic modulus ntawm 0.8-1.5 MPa, nthuav tawm elastic rov qab zoo thiab zoo nqus tau siab- zaus vibrations, muab cov nyhuv cushioning zoo tshaj plaws. EVA pads muaj ib tug me ntsis elastic modulus ntawm 1.2-2.0 MPa, muab zoo elastic stability thiab tsawg susceptibility rau kub hloov. Polyurethane pads muaj qhov siab tshaj plaws elastic modulus, ncav cuag 2.5-4.0 MPa, nthuav tawm siab rigidity thiab zoo heev load-cov kabmob muaj peev xwm. Nyob rau hauv cov nqe lus ntawm kev laus tsis kam, cov ntaub qhwv roj hmab yog qhov yooj yim rau degradation nyob rau hauv ultraviolet lub teeb thiab oxygen. Kev laus tsis kam ntawm cov roj hmab zoo tib yam yog li 5-8 xyoo, thaum cov roj hmab hloov kho neoprene tuaj yeem txuas ntxiv mus rau ntau dua 10 xyoo. EVA pads, vim lawv cov qauv molecular ruaj khov, muaj huab cua zoo dua li cov roj hmab zoo tib yam, nthuav tawm qhov kev hloov pauv tsawg kawg hauv ib puag ncig xws li -40℃txog 60 degree, nrog kev laus tiv thaiv ntawm 12-15 xyoo. Polyurethane pads muaj qhov zoo tshaj plaws kev laus tiv thaiv; lawv cov saw hlau molecular muaj cov pab pawg polar, uas muaj zog tiv thaiv ultraviolet lub teeb thiab tshuaj lom neeg corrosion. Nyob rau hauv ib puag ncig hnyav, lawv cov kev laus tiv taus tuaj yeem tshaj 20 xyoo, thiab lawv tsis tshua muaj kev tawg, tawv, thiab lwm yam kev laus. Cov kev sib txawv no tso cai rau peb cov ntaub ntawv hloov mus rau cov huab cua sib txawv thiab taug qab cov kev xav tau.
Qhov kev xaiv ntawm qhov tawv ntawm lub tsheb ciav hlau cuam tshuam li cas rau txoj kev txav ntsug ntawm txoj kev thiab lub log -rail dynamic load?
Kev xaiv qhov nruj ntawm txoj hlua tsheb ciav hlau muaj qhov cuam tshuam loj rau txoj kev txav ntsug ntawm txoj kev thiab lub log -rail dynamic load; ob leeg yog inversely cuam tshuam. Thaum qhov nro ntawm cov ntaub ntawv taug qab tsawg dhau lawm, nws yuav ua rau muaj kev hloov pauv loj nyob rau hauv lub log -rail load. Thaum qhov no tuaj yeem ua tau zoo tsis muaj kev vibration thiab txo qhov cuam tshuam tam sim ntawm lub log thiab kev tsheb ciav hlau, kev hloov pauv ntau dhau yuav ua rau kom muaj qhov dav dav ntawm txoj kev tsheb nqaj hlau, cuam tshuam rau kev taug qab smoothness. Kev pabcuam ntev -ntev yuav ua rau muaj teeb meem xws li cov neeg pw tsaug zog uas tsis muaj kev txhawb nqa thiab txo qis tamping ceev ntawm lub txaj ballast. Yog hais tias qhov nruj ntawm cov ntaub ntawv taug qab yog siab dhau lawm, qhov kev hloov ntsug ntsug yuav raug txo kom tsawg, thiab cov geometry khiav yuav ruaj khov dua. Txawm li cas los xij, lub peev xwm buffering yuav tsis muaj zog, thiab lub zog dynamic ntawm lub log thiab kev tsheb nqaj hlau yuav nce ntxiv. Qhov no yuav ua kom nrawm nrawm ntawm cov hlua thiab cov log tsheb, thiab tib lub sijhawm, raug cov neeg pw tsaug zog thiab lub txaj ballast kom muaj kev cuam tshuam ntau dua, ua rau lawv lub neej ua haujlwm luv. Kev xaiv nruj nruj yuav tsum tau yoog raws lub qag load thiab ceev ntawm txoj kev khiav. Piv txwv li, siab- tsheb ciav hlau ceev, nrog rau nws lub teeb qag load thiab kev kub ceev, yuav tsum tau ib tug khiav pad nrog ib tug nruj nruj (15-25 kN / mm) kom sib npaug ntawm kev xaav thiab dynamic load; hnyav-haul railways, nrog rau lawv hnyav qag load, yuav tsum tau ib tug khiav pad nrog nruj dua (25-35 kN / mm) los tswj ntsug txav thiab tiv thaiv ntau dhau deformation; Cov pa tsheb ciav hlau tuaj yeem siv cov ntaub ntawv taug qab nrog qhov qis qis (10-20 kN / mm) txhawm rau ua qhov tseem ceeb ntawm cov nyhuv buffering.
Dab tsi yog qhov yuav tsum tau nruj me ntsis rau qhov flatness thiab thickness sib txawv ntawm cov pawm ntawm cov kab siab -ceev tsheb ciav hlau? Vim li cas cov kev cai no nruj heev?
High - Cov kab tsheb ciav hlau ceev muaj qhov yuav tsum tau nruj heev rau qhov flatness thiab thickness sib txawv ntawm cov ntaub qhwv. Lub flatness sib txawv yuav tsum tau tswj nyob rau hauv 0.1 mm / m, thiab thickness sib txawv ntau yam yog ± 0.2 hli, deb tshaj qhov yuav tsum tau rau cov pa railways. Cov kev cai nruj no yog los ntawm cov yam ntxwv ntawm kev ua haujlwm siab - cov tsheb ciav hlau ceev: High- cov tsheb ciav hlau ceev ua haujlwm ntawm kev kub ceev, thiab cov lus teb dynamic ntawm lub log thiab cov tsheb ciav hlau yog qhov rhiab heev. Tsis txaus flatness ntawm rail pads tuaj yeem ua rau qhov siab sib txawv ntawm qhov sib txawv ntawm txoj kev tsheb ciav hlau, uas ua rau tsis muaj kev ntxhov siab hauv zos ntawm cov ntsia hlau. Qhov no ua rau lub log raws sij hawm- kev tsheb nqaj hlau cuam tshuam thaum lub tsheb ciav hlau hla, cuam tshuam rau kev caij tsheb thiab ua rau muaj kev cuam tshuam ntawm kev vibration. Kev sib txawv ntawm thickness ntau dhau ua rau qhov tsis sib haum xeeb ntawm cov tsheb ciav hlau sib txawv hauv tib seem, ua rau asynchronous ntsug txav ntawm cov ntsia hlau hauv qab load. Qhov no cuam tshuam rau tag nrho txoj kev du du, imposes ntxiv dynamic loads ntawm lub tsheb ciav hlau wheelsets, thiab exacerbates lub log -rail hnav thiab qaug zog kev puas tsuaj rau cov qauv khiav. Tsis tas li ntawd, high{14}} tsheb ciav hlau ceev muaj cov kev xav tau siab heev rau cov neeg caij tsheb; Txawm tias me me sib txawv ntawm cov tsheb ciav hlau pads yog amplified nyob rau hauv lub carriage, cuam tshuam cov neeg nrog caij. Nyob rau tib lub sijhawm, cov kev xav tau nruj me ntsis yog qhov tseem ceeb los ua kom muaj kev sib haum xeeb ntawm cov tsheb ciav hlau thiab cov hlua thiab cov neeg pw tsaug zog, tiv thaiv qhov tsis sib xws uas tuaj yeem ua rau muaj kev ntxhov siab ntau hauv zos thiab ua tsis tiav ntxov.
Cov teeb meem kev ua tau zoo dab tsi tshwm sim nrog cov tsheb ciav hlau hauv qhov chaw qis - qhov kub thiab txias? Cov teeb meem no yuav daws tau li cas los ntawm kev txhim kho cov khoom siv?
Rail pads yog qhov ua rau peb qhov teeb meem kev ua haujlwm loj hauv qhov qis- qhov kub thiab txias (hauv qab -20 degree): elasticity degradation, nce brittleness, thiab qhov me me shrinkage. Elasticity degradation ua rau txo qis hauv ncoo lub peev xwm cushioning thiab nce lub log-rail dynamic load; nce brittleness ua rau lub ncoo ua rau tawg thiab tawg nyob rau hauv kev co thiab cuam tshuam; dimensional shrinkage tuaj yeem ua rau qhov sib txawv ntawm lub ncoo thiab lub txaj pw, cuam tshuam rau kev ruaj ntseg ntawm kev txhawb nqa. Cov teeb meem no tuaj yeem daws tau zoo los ntawm kev txhim kho cov ntaub ntawv: Rau cov khoom siv roj hmab, cov roj hmab nitrile lossis cov roj hmab silicone uas muaj zog txias tuaj yeem muab ntxiv los hloov ib feem ntawm cov roj hmab ntuj, thaum cov yas tuaj yeem muab ntxiv los txhim kho qhov hloov pauv ntawm cov saw molecular thiab txo cov iav hloov kub, kom lub ncoo tseem tuaj yeem tuav zoo elasticity ntawm qhov kub thiab txias; rau EVA ncoo, qhov qis- qhov kub thiab txias tuaj yeem txhim kho los ntawm kev kho qhov sib piv ntawm ethylene rau vinyl acetate, nce cov ntsiab lus vinyl acetate, los yog qhia elastomer modifiers; rau polyurethane pads, copolymerization hloov kho thev naus laus zis tuaj yeem siv los qhia cov ntu hloov tau yooj yim, xws li polyether polyols, rau hauv cov saw molecular los txhim kho elastic rov ua haujlwm ntawm qhov kub thiab txias, thaum cov tshuaj tua kab mob thiab tshuaj tua kab mob tuaj yeem ntxiv los tiv thaiv qis - kub thiab kev ua haujlwm degradation. Tsis tas li ntawd, siv cov txheej txheem kub-resistant rau cov khoom siv saum npoo tuaj yeem txo qhov kev cuam tshuam ntawm qhov kub thiab txias ntawm cov khoom ntawm cov khoom siv ntawm cov tsheb ciav hlau thiab txuas ntxiv lawv lub neej kev pab cuam.
Dab tsi yog qhov cuam tshuam cascading ntawm kev laus thiab tsis ua haujlwm ntawm cov tsheb ciav hlau ntawm cov qauv kev khiav tsheb thiab kev ua haujlwm tsheb ciav hlau? Peb tuaj yeem txiav txim siab li cas yog tias tsim nyog hloov pauv?
Kev laus thiab tsis ua haujlwm ntawm cov tsheb ciav hlau tuaj yeem ua rau muaj ntau yam teeb meem cascading nyob rau hauv ob qho tib si txoj kev khiav thiab tsheb ciav hlau khiav lag luam. Rau cov qauv kev khiav, qhov elastic decay tshwm sim los ntawm kev laus tso cai rau lub log -rail thauj khoom ncaj qha mus rau cov pw tsaug zog thiab ballast, exacerbating sleeper cracking thiab ballast pulverization. Ib txhij, hardening los yog kev puas tsuaj rau cov ntaub qhwv tuaj yeem ua rau tsis sib xws ntawm cov ntsiab lus kev tsheb nqaj hlau, ua rau muaj kev sib txawv hauv kev taug qab geometry thiab ua rau muaj kev pheej hmoo ntawm kev puas tsuaj. Rau kev ua haujlwm hauv tsheb ciav hlau, kev ua haujlwm poob qis ua rau lub log nce ntxiv -rail dynamic loads thiab intensified lub tsheb ciav hlau kev co, txo kev caij tsheb kauj vab thiab ua kom ceev hnav ntawm cov khoom xws li cov bogies, nce cov nqi kho khoom. Nyob rau hauv cov xwm txheej hnyav, kev txhawb nqa qhov khoob uas tsim los ntawm cov ntaub qhwv tsis tau tuaj yeem ua rau lub caij tsheb ciav hlau tsis ruaj khov, ua rau muaj kev hem thawj rau tsheb ciav hlau kev nyab xeeb. Kev txiav txim siab los hloov lub ncoo yuav tsum tau ua raws li kev sib xyaw ntawm kev tshuaj xyuas qhov muag thiab kev ntsuas kev ua tau zoo: Kev pom, yog tias lub ncoo pom pom pom pom kev tawg, tawv tawv, qhov tuab ntawm ntau dua 10%, lossis tawg lossis tawg, nws yuav tsum tau hloov tam sim ntawd; Nyob rau hauv cov nqe lus ntawm kev ua tau zoo, lub cushioning kev ua tau zoo yuav tsum tau sim los ntawm kev poob rauj test. Thaum qhov cuam tshuam qhov nqus tau poob qis dua 60% ntawm tus nqi pib, lossis thaum lub ntsuas phoo qhov sib txawv ntawm qhov chaw tshaj 30% ntawm tus nqi tsim, batch hloov yuav tsum pib.