Plywood yog cov khoom siv hauv tsev uas muaj cov txheej txheem nias thiab nplaum ntawm cov ntoo veneer. Nyob rau hauv cov ntaub ntawv no, cov ntoo fibers nyob rau hauv alternating txheej yog teem perpendicular rau ib leeg. Qhov no muab lub zog plywood nyob rau hauv ob qho tib si cov lus qhia, thaum nyob rau hauv dog dig ntoo nws tsuas yog hla lub grain. Cov khaubncaws sab nraud povtseg yog siv los khaws cov ntoo saum toj thiab hauv qab rau tib qho kev taw qhia.
Daim ntawv thov
Plywood muaj lub zog, durability, lightness thiab rigidity. Nws kuj muaj zog tiv thaiv deformation, dabtsi yog khoov thiab splitting. Hauv yuav luag txhua lub khw muag khoom kho vajtse, nws tuaj yeem yuav ntawm tus nqi pheej yig. Plywood, muab nws cov phooj ywg ib puag ncig, yog siv tsis tau tsuas yog nyob rau hauv ib txwm siv tej yaam num, tab sis kuj nyob rau hauv shipbuilding, tsim thoob dej yug ntses thiab tso tsheb hlau luam.
Kev siv cov khoom siv no los tsim cov rooj tog zaum thiab kev faib tawm yog dav. Nws lub zog siab tso cai rau nws siv ua ke nrog cov ntoo tsis tu ncua lossis lwm yam khoom siv. Qhov no versatility thiab sustainability ntawm sab hauv plywood tau coj mus rauvim tias nws tau dhau los ua kev nyiam nrog cov neeg tsim qauv thiab cov khoom tsim sab hauv.
Thaum yuav cov khoom no, thov nco ntsoov tias muaj ntau qib sib txawv. Qhov kev muab qhab nia ib txwm siv cov lej los ntawm 1 txog 4, nrog rau tsab ntawv E - qib tseem ceeb uas tsis pub muaj qhov tsis xws luag. Qib 1 - qhov zoo tshaj plaws, xyaum tsis muaj qhov tsis xws luag, polished zoo heev. Qib 4 - tsis tshua muaj txiaj ntsig, feem ntau muaj qhov siab tshaj plaws ntawm qhov tsis xws luag. Muab ob npaug rau cim. Thawj tus lej lossis tsab ntawv hais txog sab nraud, thiab tus thib ob mus rau sab hauv. Txhua yam muaj nws qhov chaw ntawm daim ntawv thov.
Pros of plywood:
- Txaus siab rau cov xwm txheej tsis zoo.
- Tsawg warp lossis tawg dua li ntoo tawv.
- zoo saib thiab siab zog ntawm tus nqi qis.
Cons ntawm plywood:
- Veneer yuav nti, nthuav tawm cov ntoo qis qis hauv qab.
- Kev puas tsuaj nyuaj kho.
- Qee hom plywood siv kua nplaum thiab formaldehyde.
Production
Nyob rau hauv cov txheej txheem tsim plywood, cov txheej txheem ntawm veneer yog thawj zaug tau los ntawm kev txiav ntoo. Ua li no, cov cav yuav tig ib ncig ntawm lub longitudinal axis, thiab lub cutter ntxuav nws (qhov tuab ntawm txhua txheej yog feem ntau tsawg dua 2.5 hli). Tom ntej no, cov nplaum yog siv rau cov khaubncaws sab nraud povtseg siv lub tshuab tshwj xeeb. Nws pab kom ua tiav ib qho kev faib tawm ntawm cov nplaum. Cov txheej yog superimposed rau ib leegphooj ywg thiab nias nruj nrog lub tshuab kub xovxwm.
Qhov kub thiab siab ua los ntawm cov txheej txheem no kom ntseeg tau tias cov txheej txheem ua raws li qhov xav tau. Lawv cov naj npawb hauv txhua daim ntawv plywood tuaj yeem sib txawv ntawm 3 mus rau 13. Lub thickness ntawm cov ntawv los ntawm cov tuam txhab sib txawv yog nyob rau hauv thaj tsam ntawm 3 hli - 30 hli. Cov ntawv loj yog 1220 x 2440 mm. Muaj lwm qhov, ntau qhov yooj yim siv. Nws tag nrho yog nyob ntawm tus neeg tsim khoom. Tus neeg siv tuaj yeem txiav lossis zom cov nplooj ntawv no raws li qhov xav tau tshwj xeeb. Muaj ntau ntau hom kua nplaum siv rau kev tsim khoom. Plywood hom, muaj pes tsawg leeg, ib puag ncig tus phooj ywg yuav tsum tau txiav txim siab ua ntej yuav.
FSF
Phenol-formaldehyde nplaum yog ib hom hluavtaws lossis hluavtaws polymer uas yog tsim los ntawm cov tshuaj tiv thaiv ntawm phenol thiab formaldehyde.
Phenolic resins muab kev sib raug zoo dua li urea-based compounds. Yog li ntawd, lawv tau siv nyob rau hauv kev tsim cov plywood muaj zog thiab zoo dua. Cov dej tsis kam ntawm cov khoom no yog siab heev. Marking yog: FSF. Lub ntsiab thiab tseem ceeb drawback ntawm formaldehyde resins yog cov teeb meem tshuaj uas ua rau lawv muaj pes tsawg leeg. Lawv siv tsis tau rau kev tsim rooj tog thiab thaj chaw nyob.
FKM
Melamine kua nplaum muaj cov tshuaj tsis zoo, tab sis qib ntawm noo noo tsis kam ntawm cov plywood qis dua. Cov khoom siv zoo li no yog siv rau qhov tsis muaj qhov yuav tsum tau ua kom muaj kev tiv thaiv noo noo thiab nce qib ntawm kev nyab xeeb. Plywood yog cim li no: FKM.
FC thiab FBA
Tsis muaj cov tshuaj phem nyob hauv cov tshuaj carbamide thiab albumin-casein kua nplaum. Yog li ntawd, plywood, nyob rau hauv zus tau tej cov uas lawv siv, yuav siv tau nyob rau hauv kho kom zoo nkauj ntawm tej vaj tse, txawm kindergartens. Nws kuj yog siv rau hauv rooj tog. Lub ntsiab tsis zoo yog tias cov khoom siv no tsis muaj dej tsis zoo. Nyob rau hauv FK plywood, ib puag ncig tus phooj ywg yog guaranteed los ntawm kev nyab xeeb carbamide kua nplaum siv nyob rau hauv nws cov ntau lawm. FBA plywood muaj albcminocasein kua nplaum.
NWS FB
Qee lub sij hawm noo noo tiv thaiv yog qhov yuav tsum tau ua ntej. Nyob rau hauv cov ntaub ntawv no, nkoj plywood yog siv. Hauv kev tsim cov khoom siv no, cov khoom lag luam zoo tshaj plaws ntawm cov kua nplaum-resistant bakelite yog siv. Xws li plywood feem ntau yog cim raws li hauv qab no: FB. Nws muaj ob qhov chaw zoo tshaj plaws, tab sis kev xaiv tsawg ntawm cov ntoo tawv uas tsim nyog rau kev siv dej hiav txwv. Raws li txoj cai, birch yog siv. Marine plywood yog qhov nyuaj dua nrhiav. Nws raug nqi ntau dua li lwm yam ntawm cov khoom siv no. Nyob ntawm txoj kev ntawm gluing, plywood subspecies yog txawv:
- FBS - impregnated nrog cawv-soluble kua nplaum thiab muaj zog tiv thaiv noo noo.
- FBV - impregnated nrog dej-soluble kua nplaum thiab muaj zog ntxiv.
Plywood ib puag ncig tus phooj ywg thiab ua mob rau kev noj qab haus huv
Cov ntaub ntawv uas muaj formaldehyde resins tam sim no, raws li European qauv, muab faib ua 3 pawg (E0, E1, E3). Daim duab qhia txog qib ntawm cov tshuaj phem. Qhov zoo tshaj plaws plywood yog E0.
Kev siv cov veneer nthuav dav qhov muaj peev xwm ntawm kev siv hom ntoo ntuj. Veneer yog cov khoom siv ntuj tsim. Txawm li cas los xij, kev tsim cov plywood yuav tsum muaj cov ntoo me me piv rau cov khoom siv ntoo. Qhov no txo cov ntoo txiav. veneer yog lwm txoj hauv kev zoo rau cov ntoo tawv.
Kev txhawj xeeb txog kev noj qab haus huv yog tshwm sim los ntawm cov kua nplaum uas siv los ua cov ntoo, vim nws muaj cov khoom tsis zoo. Qhov no tshwj xeeb tshaj yog muaj tseeb rau phenol thiab formaldehyde. Tsis ntev dhau los lawv tau pom tias muaj kev nyab xeeb rau kev noj qab haus huv, tab sis tam sim no cov kev xav ntawm cov kws tshaj lij tau hloov pauv ntau. Kev tshawb fawb qhia tias cov tshuaj no cuam tshuam rau tib neeg txoj kev noj qab haus huv.
Kev ua xua, mob taub hau, teeb meem ua pa thiab txhua yam mob yog qee yam teeb meem tshwm sim los ntawm cov tshuaj no. Carcinogenic zog kuj raug ntaus nqi rau phenol-formaldehyde compounds. Qhov feem pua ntawm cov teeb meem tshuaj nyob rau hauv niaj hnub plywood yog me me, tab sis lawv muaj nyob. Qhov tseeb no yuav tsum tsis txhob ignored.
Txhob tsim txom
Kev tshawb fawb niaj hnub tsis nyob twj ywm. Cov txheej txheem raug tsim los pab ua kom cov phooj ywg ib puag ncig ntawm plywood. Ib qho kev daws teeb meem yog los tsim cov nplaum hloov kho raws li phenol-formaldehyde resin. Nplej hmoov thiab chalk tau nkag mus rau hauv nws cov muaj pes tsawg leeg, uas ua rau kom elasticity thiab viscosity ntawm cov nplaum sib koom. Txawm li cas los xij, lawv yog cov khoom ntuj tsim. Qhov no txhim kho toxicity thiabpab txhawb kev txuag hluav taws xob hauv kev tsim khoom.
Tseem muaj kev sib koom ua ke los ntawm cov tuam ntxhab thoob plaws ntiaj teb los tsim cov nplaum nplaum rau ib puag ncig kom ua plywood yog cov khoom siv nyab xeeb rau tib neeg thiab ib puag ncig. Lwm txoj hauv kev yuav yog cov nplaum xws li soy-based amino acids. Lawv tsis muaj cov kab mob uas ua rau muaj roj. Kev nyab xeeb plywood kuj yog tsim nrog cov agro fiber lossis nplej straw core, ntxiv ua rau nws ib puag ncig raws.
Russia yog ib lub tebchaws uas muaj kev lag luam tsim kho ntoo. Peb cov plywood ntau lawm muaj ib tug ntev kev lig kev cai thiab ib theem siab ntawm kev txawj ntse. Kev nplua nuj hav zoov thiab kev sib tw ntau lawm muab lub sijhawm zoo los nqis peev hauv cov thev naus laus zis tshiab, ua rau muaj kev cuam tshuam ntau dua rau cov plywood.
