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Chng 5

BAO B GIAY - BAO B VAN CHUYEN HANG HOA (BAO B N V GI I)

5.1 GII THIEU BAO B VAN CHUYEN HANG HOA

5.1.1 Go

T co xa, ngi ta a dung go lam vat lieu e ong kien vi so lng hang hoa ln e e van chuyen. Luc o, lng hang hoa c van chuyen thng mai con thap, go c tieu dung vi so lng khong cao, cha gay thiet hai cho rng va cha anh hng ln en moi trng. Thng mai hang hoa cang ngay cang phat trien, nhu cau ve bao b van chuyen cang tang cao cung vi viec khai thac rng vt mc e dung cho rat nhieu muc ch nh xay dng... a khien cho nhu cau ve go tang cao nen khong the co u go e ap ng nhu cau, do o bat au co nhng vat lieu khac canh tranh vi go. ay la ieu noi bat ang quan tam cua giay ba gn song v tnh nhe hn go rat nhieu, giup cho chi ph van chuyen giam thap. Tuy nhien, hien nay van con mot so t trng hp hang hoa van c ong kien bang thung go do tnh chat c ly cua go cao.

Nhng ac tnh cua thung bang go cha hang hoa chuyen ch phan phoi tuy thuoc vao loai go c dung. ac tnh quan trong yeu cau oi vi thung go la chu c tai trong va chu va cham c hoc. Go cua nhng cay tung, bach hay go than mem th co tnh chu cua ap lc cao nhng chu tai trong thap hn loai go cng; so vi go cng th go than mem co the b v ra khi ong inh.

Viec khai thac go e san xuat thung cha ng hang hoa cang luc cang ton chi ph qua cao va cang tien sau vao s pha hoai moi trng. Trung bnh ch co 65% than cay c tao thanh thung go. Vi khuynh hng tang s hu dung cua vat lieu go cho viec ong thung cha hang a hnh thanh cong nghe san xuat go ghep va go dan. Go dan c dung nhieu e san xuat cac thung bang go hnh tron ng chat long ma ngay nay van con dung e cha ru vang. Phng phap ghep noi nhng tam van thanh nhng thung cha ng

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c cho thay hnh 5.1.

Hnh 5.1: Thung cha ng c cau tao bi go ghep

5.1.2 Bao b van chuyen bang plastic

Hien nay bao b van chuyen hay bao b ngoai bang vat lieu HDPE nh cac ket c dung e cha ng chai thuy tinh, cha bia hoac nc ngot co gas ang rat pho bien va tien li co khoi lng nho hn go rat nhieu va tnh tai s dung cao.

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Hnh 5.2: Ket bang HDPE cha chai nc ngot hoac chai bia e van chuyen phan phoi

Nguyen lieu HDPE che tao ket c phoi tron HDPE phe thai vi ty le cao khoang 8090% va HDPE mi khoang 1020% tren tong nguyen lieu s dung; vi ieu kien la nguyen lieu tai sinh khong b nhiem ban lam giam tnh ben c cua bao b.

Ben canh o tnh chat c hoc cua ket cang thap khi c san xuat t nha tai sinh nhieu lan, se chong lao hoa, de v hn theo thi gian s dung, khong the cai thien bang cac phu gia on nh.

Can chu y rang ket co the b nt v tren be mat do s oxy hoa, s nhanh chong lao hoa vat lieu bi s tiep can tia cc tm. Tuy thuoc vao thi gian phi di anh nang mat tri co the anh hng ang ke en tnh ben c hoc cua ket. Thi gian s dung ket bang HDPE co the la 10 nam hoac 15 nam, hoac co the hn tuy theo ieu kien ap dung.

5.2 CAU TAO BAO B GIAY - NG DUNG

5.2.1 ac tnh

Ngay nay giay chiem hn phan na trong tong so nguyen lieu e lam bao b. Nh tien bo cua khoa hoc ky thuat, giay cac loai c san xuat ai tra vi gia thanh thap.

Giay c s dung pho bien bi mot so tnh chat ac trng nh:

- Tnh ben c hoc (tuy khong cao nh cac loai vat lieu khac) - Nhe. - De huy, khong gay o nhiem moi trng. - Tai sinh de dang.

Ben canh o giay co nhng khuyet iem nh: - De rach, tham nc, tham kh, tnh de xe rach cang cao khi ham am

cang cao. - o am cho phep am bao tnh ben cua giay la 6-7%. - Quy cach c quy nh bi trong lng tren mot n v dien tch giay:

g/m2.

e tang o ben c cho giay, ngi ta thng ghep nhieu lp giay lai vi nhau. Cac loai giay co chat lng khac nhau la do s ket hp vi nhng loai nguyen lieu khac nhau. Giay la vat lieu bao b lau i khong gay hai moi trng, a c x l e co the tang cng tnh khang hi am, chong oxy hoa,

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khang vi khuan, chong dnh, kho chay, chong tham nc, be mat co o trt cao, o bong cao, chong tham chat beo. Giay hien nay co the co hang loat cac tnh chat quang hoc va o xop mong muon, va bang cach s dung cac lp trang kep tren mot mat; co the tai tao hnh anh chnh xac khi in ong ong. Ngoai ra, o ben c hoc a khien cho giay co kha nang chay tren may cang dan theo chieu doc cua giay ma khong b t hay xe rach.

Giay co the lam t nguyen lieu rm ra, go vun, vo cay, bot go, giay thai, go than mem, go than cng.

Cau tao cua nguyen lieu go:

Chat lng thanh pham c quyet nh bi nguyen lieu cellulose ban au hn la cac hoa chat phu gia, o chnh la chieu dai cua cellulose. S khac nhau gia go ty trong cao va ty trong thap anh hng ln en cau tao cua giay.

Thanh phan chnh cua cac te bao go

Cellulose: Cellulose la mot polyme gom 8000-10000 goc glucose. Tnh chat cua si cellulose phu thuoc o dai mach polyme, mc o thang, s sap xep song song bi cac mach polyme. No khong b hoa tan bi kiem, clorin, do o giay tay trang ch co the loai c lng lignin ma khong ton that cellulose, nhng gay giam ac tnh ben chac cua si cellulose.

Hemicellulose: phan t lng thap gom 100-200 goc monomer cua xylose, mannose arabinose, galactose va axit uronic. Hemicellulose tan trong dung dch kiem, co kha nang b thuy phan va co the lien ket vi cac hoa chat phu gia.

Lignin: la polyme nhiet deo, co nhanh, nhan thm alkyl, co kch thc cung nh khoi lng phan t khong on nh, gom cac monomer la phenyl propane tan trong kiem va dung dch nc clor cho dan xuat mau nau en va tr nen mem deo 160oC pH 4.

Go than mem: loai go nay gom 40-50% cellulose, 15-25% hemicellulose, 26-30% lignin. Than go mem co si cellulose dai gap 2,5 lan so vi than go cng. Than go cng dung e san xuat van, tam phang mn hn nhng kem ben c hoc hn so vi go mem. Nh vay phai cat go sao cho khong pha v si cellulose e lam giay c tot, ben canh o lignin phai c loai bo i e co the thu c si cellulose va giup chung sap xep song songkhi lam giay. Si cellulose co the b gay nat tuy cac cong oan che bien giay.

Trong qua trnh che tao giay, cac si cellulose c sap xep lai v tr bang ap suat rat ln ep len be mat e tao dang tam, co the dung phu gia nh casein va protein au nanh hoac tinh bot e tao lp ao ben ngoai tam giay.

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- Chat mau vo c thng chiem 70-90% chat kho cua lp ao giay e tao be mat khac biet cho giay ben trong, giup lp ao nang cao tnh phang, de in an, chat lng in cao, tao nhng tnh chat ac biet theo yeu cau, cac chat trang e ao giay c dung nh kaolin, CaCO3, c dung ket hp vi cac khoang chat khac e tao nen o bong be mat giay.

Nh tien bo ky thuat ma vat lieu giay c x ly e tang cng tnh khang hi am, kho chay, ngan c nc, o trt cao, o bong cao va co cac lp trang chong tham dau. Giay hien nay co the co hang loat cac tnh chat quang hoc va o xop mong muon va bang cach s dung cac lp trang thch hp, co kha nang in an cao (nh giay cua cac tap ch at tien), ngoai ra o ben c hoc cao va kha nang chu lc keo (theo chieu doc) khi chay tren may khien giay khong b t hoac rach.

Bang 5.1: Phan loai nguon nguyen lieu lam giay (theo s phan loai cua Cong hoa Lien bang c)

Loai Nguon nguyen lieu I Cellulose t si cotton phe thai II Cotton phe thai cong vi 50% cellulose t go hoac rm ra III Cellulose t rm ra, ba ma (khong co cellulose t go) IV Cellulose t go 50% V Cellulose t go > 50%

Loai Nguon nguyen lieu trang be mat giay e chong tham

Cac loai vat lieu khac nhau c dung e nang cao chat lng giay cung c e cap di ay

1 Dau hoa c san xuat t dau mo tho hoac t than nau. Dau nay co o tham cao va iem nong chay nam gia 52-56oC. No c tham vao giay bang cach ngam giay vao dau dang long, hoac phun no len be mat giay. (H.5.3)

2 Sap hay parafin ran la nguyen lieu co nguon goc t cong nghe tinh loc dau hoa c un en iem nong chay tren 80oC va tham thau vao giay hoac phun len giay (H.5.3).

3

Mang polyethylen hay polypropylen phu len be mat giay hoac tham thau dang nha long. Loai giay c nang cao tnh chong tham bang nha thng c dung trong san xuat giay ba gn song va giay ba cng e lam nhng bao b van chuyen. Nhng vat lieu plastic khac nh la polyvinyl chloride, polyvinyl acetat, polyvynyl acrylate, cellulose, ete, latex, thng c dung e lam cac bao b ep mat. Nhng vat lieu nay thng c phu len mat giay va c ep nhiet (H.5.4). Giay c x ly nh vay goi la giay trang be mat, co tnh khong tham nc hay am.

4 La nhom cung thng c dung cung vi giay. V du nh giay cai tien c

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lam thanh ba lp: lp th nhat thng la giay; lp gia la AI va lp th ba la lp polyethylene. Cuoi cung san pham la mot vat lieu ben chac co the chong tham hi nc va hi gas va rat thch hp cho bao b thc pham.

Loai nguyen lieu V la loai chat lng cao v lng si cellulose t go co ac tnh ben c cao, va thng s dung si cellulose mi t go thng t go than mem. Si cellulose t vai si phe thai hay t giay phe thai, c x ly, tai sinh nhieu lan se b ngan mach, o ben c kem.

5.2.2 Cac loai giay bao goi: thanh phan va tnh chat ng dung

Giay dung e bao goi c chia thanh cac nhom theo thanh phan phoi lieu:

Giay lam bao b thc pham thng la dang bao b h v giay co tnh tham kh hi rat cao. Ch trng hp giay c trang phu cac mang plastic hoac mang plastic vi Al la chong tham kh hi rat cao mat trong lan mat ngoai nham ngan can hoan toan tac ong cua moi trng ngoai len thc pham c cha ng va tac ong gay h hong bao b. Do o lng giay s dung trong nganh thc pham rat ln, trong o loai giay b cng, giay kraft lam carton gn song chiem lng cao nhat, con lng giay goi thc pham ch lng thap oi vi cac quoc gia phat trien cung nh ang phat trien. Ch rieng Nhat Ban s dung mot lng ln giay thng la giay t nguyen lieu rm ra, ay, coi va e goi banh truyen thong t ngu coc, va e trang tr; ho a dung giay phan bo nh sau:

- Giay ba cng lam hop (bao b ngoai) e ng banh - Tui, gio xach qua bang giay ba cng. Tat ca eu c in an

trang tr ep.

Giay c s dung nhieu nh the nhng se c tai sinh de dang khong gay o nhiem moi trng, va tan dung nguon cellulose cua at nc (ay, coi, rm ra, bot go, go vun t nganh xay dng dan dung), giam i mot lng kha ln plastic lam cac loai bao b trong cung nh bao b ngoai cho loai banh bao quan ngan ngay.

Di ay la ky hieu loai nguyen lieu giay e bao goi:

AP1 100% hon hp cac loai giay phe lieu

AP2 30% cua AP1 + ; 70% giay phe lieu chat lng cao hn

AP3 25% si cellulose loai 2 va 75% giay phe lieu chat lng cao, hoac 100% giay phe lieu chat lng cao

AP4 30% si cellulose thuan khiet va 70% giay vun chat lng cao hn hoac 100% giay phe lieu chat lng cao nhat

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ZP1 100% si cellulose t mat go (va co the en 30% giay phe lieu)

ZP2 100% si cellulose loai 2 tay bang sulphite (va co the phoi en 30% giay phe lieu chat lng cao hn)

ZP3 100% cellulose loai 2 tay bang sulphite co the phoi en 30% go hoac 30% giay phe lieu chat lng cao hn)

ZP4 65% cellulose thuan khiet a dc tay trang bang sulphite va c phoi tron vi 35% go

ZP5 100% si cellulose thuan khiet

NaP1: 100% si cellulose thuan khiet a sulphite hoa

NaP2: 50% lng NaP1 phoi tron vi 50% giay kraft phe lieu

Ghi chu:

- Giay phe thai chat lng cao: giay van phong, giay tap hoc sinh a s dung.

- Si cellulose loai 2: cellulose t go vun hoac cellulose con lan ham lng kha ln cua hemicellulose hoac lignin.

- Giay phe lieu chat lng cao nhat: giay phe thai t quy trnh san xuat giay chat lng cao, cat ra, cat theo kch thc... cha in an hay nhiem ban.

- Si cellulose thuan khiet la cellulose khong lan hemicellulose hay lignin.

Giay c cuon i qua be sap hoac parafin ran a c nau chay. Giay sau khi c tham sap hoac parafin c cho qua be nc lam nguoi va c say kho, cuon lai.

Hnh 5.3: Cong nghe trang sap len giay

Hat plastic c gia nhiet chay long va c qua may un thoi thanh mang va ghep len be mat giay.

Giay kraft lam bao b: la loai giay co mau hi nau, lam t si cellulose c

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x ly vi muoi natrium sulfat (sulfat hoa) va khong tay trang bang phng phap sulphite. Giay kraft dung e lam cac loai bao to e ng ngu coc hay ximang... thng nang t 70-75g/m2; Giay kraft mong nhat la 6-7g/m2; giay kraft e che tao ba gn song lam thung cha, bao b n v gi i, co khoi lng 85180g/m2. Giay kraft co the tay c, nhng khi b tay o dai cua no se giam i. Hn 60% san lng giay kraft dung e lam giay ba cng, giay ba gn song (hoac carton gn song).

Hnh 5.4: Cong nghe phu (trang) plastic len be mat giay

5.3 GIAY BA GN SONG - CAU TAO BAO B VAN CHUYEN

Vi tien bo ky thuat hien nay, bao b carton gn song co the co hau het cac tnh chat c hoc can thiet nh: chu s e nen, va cham, ap lc trong cac ieu kien moi trng co o am cao, do tao nen cac lp song, tang cng so cac lp giay ba thanh 3,5 hoac 7 lp. Ngoai ra co the tang cng o ben c hoc cua cac thung cha bang cach gia cng cac goc, cac be mat at o ma sat thch hp, e khong trt len nhau giup on nh thung tren pallet. e tang cng tnh cach nhiet cho thung co the a polyurethan xop vao cac ranh song. e bao ve an toan cho cac kho hang, cung co the x ly thch hp e ha thap tnh boc chay cua thung xuong 60%.

Hien nay bao b carton dn song ng au trong cac loai bao b khong gay hai moi trng, vi ty le 75% so lng nguyen lieu che tao la loai giay kraft tai sinh (co the at en 100% nhng ch nham muc ch thu nhat lai). Ty le nay c chap nhan bi qui nh cua EEC. V vay mot bao b rieng le c san xuat se cha 75% si giay tai sinh va 25% si giay nguyen chat. Khi tnh en chat lng thu c th ta thay ay la mot tien bo ky thuat ln ong thi hieu qua kinh te ln.

5.3.1 Cau tao cua ba giay gn song - Bao b van chuyen

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Giay ba gn song thc hien chc nang ac biet quan trong o la vat lieu tao nen bao b ngoai hnh khoi ch nhat e cha ng mot lng ln n v ban le, giup thuan tien trong phan phoi van chuyen, lu kho va kiem tra quan ly. Qua trnh cai tien cac nguyen lieu tao nen, giay ba gn song la mot trong nhng bc tien ln nhat cua the ky 20 (giay ba gn song c phat minh trong the ky 19 va c s dung pho bien, che tao bang c gii vao au the ky 20). No c san xuat tren may co toc o 50200m/phut, kho rong hn 2m va co the c ghep 3, 5 hoac 7 lp. Nhng ac tnh ve cng lc cua no tuy thuoc vao loai giay c dung, bien o gn song va chat lng cua keo. Cac dn song co hnh vong cung nham muc ch tang kha nang chu lc len cao nhat (nh cac gian vom, khung hnh vong cung trong ky thuat xay dng dan dung cung nh cau ng). Hnh 5.5 mo ta quy cach cua cac loai gn song lam tang cng o chu ap lc va tai trong oi vi giay ba gn song lam bao b van chuyen hang hoa (thung cha).

Hnh 5.5: Cac loai gn song A, B, C, D

Hnh 5.6: Cac loai giay ba gn song 5 lp, 7 lp ket hp cac loai song khac nhau

Cac loai giay gn song - tnh chat

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Tuy thuoc vao loai hang va cach thc xep hang ma co nhng yeu cau cng lc khac nhau. Hnh 5.7 mo ta s va cham va phng chu lc cua ba gn song.

Hnh 5.7: Loai lc tac ong va phng chu lc cua giay ba gn song a) Phng chu ap lc va cham cua giay gn song

b) Phng chu tai trong cua giay gn song.

Loai gn song A, co bc song dai va chieu cao song cao co ac tnh chu lc va cham tot nhat. Giay ba gn song loai A se c dung e ong goi cac loai hang hoa co the b anh hng bi va cham c hoc.

Loai gn song B, co bc song ngan va chieu cao song thap cung co kha nang chu c va cham c hoc nhng ac biet co kha nang chu tai trong nang so vi loai gn song A, do o giay ba gn song kieu B chu yeu c dung e ong goi cac hang hoa co tai trong cao nh o hop.

Loai gn song C, ket hp nhng ac tnh cua loai A va loai B nen co tnh nang chu c tai trong va va cham.

Loai gn song D, co bc song ngan chieu cao song rat thap nen kha nang chu tai trong cung nh va cham eu rat kem v the ch c dung lam bao b thng mai bao goi cac loai hang hoa co trong lng nho va t chu tac ong c hoc.

Da vao nhng ac tnh cua loai gn song e xac nh phng cach tao thung cha hnh khoi ch nhat bang giay ba gn song, co kha nang chu lc

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tac ong va chu tai trong tot nhat.

Cau truc trien khai cua bao b ngoai bang ba gn song nh hnh 5.8a, khi lap thanh thung cha phai co cau tao gn song nh hnh 5.8b: be mat xung quanh co ng noi nh cua gn song thang ng vi mat ay, mat ay va nap co phng cua ng noi nh song song song nhau va song song vi mot mat phang ay.

Hnh 5.8: Phng phap tao hnh cua bao b giay gn song

a) Hnh trien khai cua thung giay ba gn song (thung carton) b) Cau truc hop c ban (phng cua gn song bieu th bang mui ten)

5.3.2 Cach sap xep hop lon thc pham vao bao b ngoai

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Khi thiet ke thung carton, phai quan tam en kha nang s dung, s tiet kiem vat lieu ba gn song va kha nang cha nhieu nhat cua thung, ac biet chu y khi bao goi ngoai cac san pham ban le dang chai thuy tinh than truc, hoac lon kim loai. Trng hp cua nhng n v ban le c bao goi dang khoi ch nhat th bao b ngoai cung co dang khoi ch nhat se c xac nh kch thc mot cach de dang.

Nhng hop kim loai dang tru tron va chai lo co the xep theo cach xep vuong hoac xep cheo nh hnh 5.9a,b.

Cach xep vuong goc: Tam cac hnh tron ay lon nam nh cua hnh vuong canh bang ng knh lon (d).

Cach xep cheo: Tam cac hnh tron ay lon la nh cua tam giac eu co canh bang ng knh lon.

Hnh 5.9: Cac cach xep hop tron vao thung ba gn song

Cach sap xep thch hp nhat (vuong goc hay cheo) co the c tnh toan tng ng vi kch thc hop, cac thong so sap xep lon nh sau:

l - chieu dai ay thung carton b - chieu rong ay thung; d - ng knh hop h - chieu cao hop (neu hop c xep trong ch mot tang, h cung la chieu

cao cua thung carton) m - so lon xep theo chieu rong n - so lon xep theo chieu dai hop N - tong so hop xep trong mot tang = m n P - dien tch toan bo be mat giay ba carton V - the tch cua thung cha

Kch thc thung, so lon sap xep, ng knh cua lon co quan he nh sau:

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- Theo cach xep vuong:

l = nd; b = md

- Theo cach xep cheo

l = nd; = + b m d[ ( )]31 12

T o co he so f bieu dien moi quan he gia cac thong so theo cac phng phap xep vuong hoac cheo:

=2Ndf

lb

Vi kieu xep thung vuong goc th f = 1, kieu xep cheo f 1,155. u iem cua viec xep hop theo cach cheo c nhan thay trong trng

hp

(i) n > 4

(ii) m = 2 va n > 8

4 < m < 14 va n > 5

m > 16 va n > 4

Khi gap hop carton, ta can phai chu y sao cho nap phai c xep song song vi chieu dai cua thung carton. Ben canh o, viec san xuat thung ba gn song lam bao b n v gi i rat quan tam en tnh kinh te la tiet kiem c giay, co ngha la at c yeu cau thung cha li ve the tch cha va giam ton hao ba giay nguyen lieu.

Hnh 5.10 la cac kch thc chieu dai, chieu rong, chieu cao cua mot thung carton.

Ty le l: b: h = 2: 1: 2, la ty le gia chieu dai, rong va cao ap ng c yeu cau the tch thung (ln nhat) tot nhat vi dien tch be mat hop toi thieu. Neu ty le nay thay oi thanh 2: 2: 1, se phai s dung them 33% nguyen lieu. Con neu ty le la 1: 1: 1 th phai s dung them 12% nguyen lieu so vi nguyen lieu dung cho trng hp ty le 2: 1: 2. Thc te e ha trong tam thung, bao am an toan thng khong theo ty le 2: 1: 2.

5.4 QUY CACH CUA BAO B VAN CHUYEN

Hnh 5.10

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5.4.1 Quy nh ve kch thc thung khoi ch nhat va khoi lng hang c cha ung

Bang 5.2: Kch thc ben trong cua thung carton va khoi lng toi a cho phep ong trong mot thung

Ky hieu thung

Kch thc (mm) Khoi lng toi a c phep ong trong thung (kg) Dai Rong cao

8

10

12

13A

13B

14

512

458

512

412

508

391

307

305

409

309

410

234

198

253

150

210

133

285

30

30

26

25

21

19

Thong thng, ngi ta dung thung carton e ong bao b van chuyen hang hoa.

Cac thung hang hoa c xep thanh kien hay khoi ch nhat tren cac pallet go e tranh khong e trc tiep tren nen kho.

Hnh 5.11: Mot trong cac cach sap xep thung hang hoa (cac n v gi i) tren mot pallet e lu kho

5.4.2 Ghi nhan bao b ngoai

Bao b giay ba gn song (bao b giay carton) cung c ghi nhan nhng yeu cau n gian so vi trng hp ghi nhan cho hang hoa n v ban le,

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thong thng co the ghi:

- Thng hieu.

- Ten san pham (co the ghi mot so chi tiet ve ac tnh vat pham). - a ch nha san xuat, ni ong bao b - quoc gia san xuat. - Han s dung. - So lng hay trong lng. - Ma so ma vach. - Cac ky hieu, dau hieu phan hang thc pham (neu co) nh dau hieu

hang Viet Nam chat lng cao.

5.4.3 Ky hieu bang hnh ve cho bao b van chuyen hang hoa (bao b n v gi i) c quy nh theo TCVN6405: 1998 va ISO780: 1997

e co c bao b tien li trong van chuyen va am bao chat lng hang hoa ben trong ta can quan tam en qui nh chung nh mot ngon ng rieng danh cho lnh vc nay.

Tieu chuan TCVN6405: 1998 va ISO780: 1997qui nh cac ky hieu quy c ghi tren bao b van chuyen e hng dan viec boc xep va bao quan hang hoa trong qua trnh van chuyen.

1- Quy cach ky hieu - y ngha

Cac ky hieu c in trc tiep tren bao b n v gi i khong bat buoc ong khung am cho cac ky hieu.

a) Mau sac cua ky hieu

Mau sac dung cho ky hieu phai la mau en. Neu mau cua bao b lam cho mau en cua ky hieu khong ro th nen chon mau sac tng phan, thch hp lam nen, tot nhat la mau cua giay traft che tao thung. Phai tranh cac mau co the nham lan vi nhan hang hoa thuoc loai nguy hiem. Tranh dung mau o, da cam hoac vang, tr khi co cac yeu cau ac biet.

b) Kch thc cua ky hieu

Cac chieu cao thong thng cua ky hieu la 100mm, 150mm hoac 200mm.

Tuy nhien, tuy theo kch thc va hnh dang cua bao b co the s dung cac ky hieu ln hn hoac nho hn.

c) So, v tr va hng cua ky hieu

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So cua ky hieu s dung cho moi loai bao b phu thuoc vao kch thc hnh dang va hang hoa cha ng ben trong.

oi vi cac ky hieu so 1,3,7,11, va 16 (xem bang 5.3) phai theo cac nguyen tac sau:

Ky hieu so 1- "De v", phai e goc ben trai cua tat ca bon mat xung quanh bao b (xem v du trong so 1 bang 5.3).

Ky hieu so 3- "Hng len tren", cung e v tr giong nh ky hieu 1

Ky hieu so 7- "Trong tam", khi co the, ky hieu nay can phai e tat ca 6 mat hoac t nhat phai e tren 4 mat lien quan en v tr thc cua trong tam

Ky hieu so 11- "V tr kep"

- Ch nhng bao b co cac ky hieu nay mi c van chuyen bang kep. - Ky hieu phai e hai mat oi dien cua bao b trong tam nhn cua ngi

van hanh thiet b khi boc xep hang hoa. - Ky hieu khong c at mat bao b se kep.

Ky hieu 16- "Quang day, ay phai at t nhat hai mat oi dien cua bao b.

- Khi bao b van chuyen c xep thanh ong, ky hieu c e sau cho co the nhn thay c.

- Can phai ac biet chu y dung chnh xac ky hieu tranh viec ap dung sai. Ky hieu so 7 va so 16 phai c e theo ung hng va v tr tng ng cua no.

- Trong ky hieu 14 "Gii han so lng xep chong len", n la so lng toi a bao b c xep chong len nhau.

2- Hnh anh ky hieu cu the

Hng dan phai c ghi ro tren bao b van chuyen bang cach s dung cac ky hieu tng ng a ra trong bang 5.3.

Bang 5.3: Y ngha, hng dan va lu y khi s dung cac ky hieu cho bao b ngoai

So ky

hieu

Hng dan Ky hieu Y ngha Tham khao/lu y - v du

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So ky

hieu

Hng dan Ky hieu Y ngha Tham khao/lu y - v du

1 De v

Cac vat ng trong bao b van chuyen de v phai boc xep can than

2 Khong dung moc tay

Khong dung moc e boc xep va van chuyen hang hoa

3 Hng len tren

Ch ra hng ung cua bao b van chuyen

4 Tranh anh nang mat tri

Bao b van chuyen khong c e di anh nang mat tri

5 Tranh nguon phong xa

Vat ng trong bao b co the b h hong hoac khong the dung c do b nhiem phong xa

6 Tranh ma

Bao b van chuyen khong c e di ma

7 Trong tam

Ch ra trong tam cua bao b van chuyen c boc xep nh mot n v le

8 Khong c lan

Bao b van chuyen khong c lan

9

Khong dung xe keo tay at ay

Khong dung xe keo tay at vao mat nay khi boc xep bao b van chuyen

10 Khong dung xe nang

Khong c van chuyen bao b bang xe nang

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So ky

hieu

Hng dan Ky hieu Y ngha Tham khao/lu y - v du

11 V tr kep

Kep vao cac mat c anh dau e boc xep bao b van chuyen

12 Dau hieu khong c kep

Bao b van chuyen boc xep bang kep tren mat co dau hieu khong c kep

13

Gii han khoi lng c phep chong len

Ch ra khoi lng toi a c phep xep chong len bao b van chuyen

14

So lng toi a c xep chong len

Ch ra so lng toi a bao b van chuyen c phep xep chong len nhau "n" la so lng bao b gii han

15

Khong c xep chong len

Khong c phep xep chong va chat tai len bao b van chuyen

16 Quang day ay

Day quang phai at vao v tr co ky hieu e cau bao b van chuyen

17 Gii han nhiet o

Ch ra gii han nhiet o e bao quan va boc xep bao b van chuyen

Cau hoi

1 Phat bieu nao di ay sai: a) Thung giay carton nhe, dai, chong va ap tot. b) Giay carton co trang phu lp plastic co tnh cach am va ngan can kh

kem.

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c) Cac loai carton gn song chu c va ap va chu nen va co nhieu cong dung.

d) Khi mua giay e che tao ba giay carton ta can quan tam en o day, o cng cua giay.

2 Bao b n v gi i cha so lng 24 hop, SP cha trong moi hop: 10SP/hop; khoi lng 100g/SP. So lng c ghi tren bao b n v gi i nh sau:

a) 100g 10 24 b) 100g 240 goi c) 24 10SP 100g/SP d) 10 hop 100g 24. 3 e de dang phan phoi van chuyen bao b thng co dang: a) Khoi ch nhat va khoi vuong. b) Khoi tru va khoi vuong. c) Dang goi. d) Khoi ch nhat.

4 e tao nen loai giay ba gn song co tnh chu tai trong cao nhat ngi ta thng ghep gia cac loai giay gn song sau:

a) A ghep vi B b) B ghep vi B

c) B ghep vi C d) A ghep vi E.

5 Cach xep cheo cac hop tru tron vao hop carton la cach xep sao cho: a) Tam cac ay tron, nam tren nh cua mot tam giac. b) ng noi tam cua cac ay tron cua hop hnh tru chnh la cac canh cua

mot tam giac eu. c) Dien tch be mat b bo trong nhieu hn so vi phng phap xep vuong. d) Cac phat bieu tren eu khong ung.

Tai Lieu Tham Khao

1. United Nations Industrial Development Organization Food industry studies No.5, Packaging and Packaging materials, New York, 1969.

2. Hanlon J. F., Paper and paper board, Handbook of Package

Engineering, 2nd Edition, McGraw, Hill Inc, New York, 1984.

3. Schenk,R.U.,Bjorksten and L. yeager. Composition and consequences of aluminium in water,beverages and other ingestibles. In Environmental Chemistry and toxicology of Aluminium , T.E. Lewis(Ed.), Lewis

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publisher,Inc.,Chelsea Michigan,1989,chap.14. 33.

4. Wade, P.Biscuit, cookies and crackers, vol.1, The Principles of the craft, Elservier Applied science Publishers Ltd.,Essex, England 1988, chap.4.

Chng 6

BAO B THUY TINH

6.1 AC TNH CHUNG CUA THUY TINH

6.1.1 ac tnh chung

Bao b thuy tinh ng thc pham gom nhng chai, lo bang thuy tinh silicat. Trc ay, thuy tinh la t goi chung cho nhng oxyt vo c dang thuy tinh hay chnh la dang cau truc vo nh hnh. Vat chat vo c thng ton tai di cac dang:

Dang kh, gom tap hp cac phan t nh O2, N2, CO2, H2, Cl2, F2, SO2..., hoac kh ion hoa plasma, hoac dang hi nh hi H2O. Dang long nh Br2, Hg...

Cac dang kh, hi hoac long eu mang tnh linh ong va co hnh dang cua vat cha chung.

- Dang ran tinh the, nh cac dang muoi ket tinh, co cac hat tinh the ri rac, kch thc tuy vao ieu kien ket tinh.

- Dang ran vo nh hnh, con goi la dang thuy tinh co the gap dang hat, dang mang, gel, hoac ong ran thanh khoi. Trang thai thuy tinh thng la trang thai ac trng cua cac hp chat vo c, c xem la trang thai trung gian cua dang ket tinh va dang long co ac tnh: trong suot, cng don nhiet o thng.

- Khi c gia nhiet th thuy tinh mem dan va tr nen linh ong, chay thanh giot hay thanh dong, o nht cang giam thap khi nhiet o cang tang; va o nht se tang dan en cc ai va mat ca tnh linh ong khi