P H A T TRIEN MODUL DINH LUONG CHUAN SU" DUNG Vf T TAI VA LOAD CELL
TS. Dang Thi^n Ngdn
Khoa Co khi Che tao mdy Dai hpc Sd ph?im Ky thudt TP. Hd Chi Minh
TOM TAT
Dinh lUdng Id mdt cdng doan quan trong trong qud trinh sdn xudt nhdm xdc djnh chinh xdc khoi lUdng nguyen vdt lieu, bdn thdnh phdm, thdnh phdm cho cdc cdng doan tilp theo hoac ddng gdi sdn phdm.
Hien nay tai cdc cd sd sdn xudt viec dinh lUdng sU dung load cell dd ddn trd nen pho biln vd bUdc ddu dd mang lai hieu qud cao. Tuy nhien, cdc thilt bi dinh lUdng ndy thUdng dUdc nhap ngoai hoac tU chi tao co gid thdnh cao vd chi phii hdp ddi vdi tUng loai sdn phdm cu thi. Do dd, vdn de tiep can, Idm chu, tU thiet
kl, chi tao module dinh lUdng chudn sU dung dUdc cho nhieu loai nguyen lieu khde nhau la cdn thiet, mang tinh thUc tien. Bdi bdo gidi thieu cdc kit qud nghien cdu vephdt triin module dinh lUdng chudn si dung vit tdi vd load cell cho dinh lUdng dang hat rdi, dang hon hdp nhdo.
Tii khod: dinh lUdng, nguyen vdt lieu, dang hat rdi, hdn hdp nhdo
ABSTRACT
Quantity is an important stage in the production process to determine accurately the volume of raw materials, semifinished and finished products for the next stage of the production or packaging pro- cess. In the production facilities, the using of the quantitative technique with load cell is currently becom- ing more popular and initially brings high efficiency. However, these quantitative equipments are usually imported or self-manufactured with high cost and suitable only for each particular product. Therefore the problem of approach, self-designing, manufacturing of standard quantitative module, which can be used for many different types of materials, are necessary and practical. This paper presented the research resulU on the development of standard quantitative module using screw and load cell for loose granules, mixturt pasty.
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Keywords: quantitative, raw materials, granular loose, pasty mixture
TAP CHf CO KHI VI$T NAM • Sd 1+2 (Thdng 1+2 nam 2012)
NGHIEN ClJfU - TRAO D O I
1. Gldl THI$U
Trong qud trinh sdn xuat, qud trinh do Iddng Idpng nguyen lieu xdc dinh, dinh Idpng nhdng vdt lieu bo sung de tao ra sdn pham vdi chat Idpng dat yeu cau cd y nghia Idn. Cdc thiet bi dinh Idpng cd mat hau het tai cdc cdng doan cua qud trinh san xuat nhd tdn trd nguyen vat lieu, cap heu cho tdng giai doan cdng nghe, dinh Idpng vd ddng gdi sdn pham.
Ddi tdpng dinh Idpng rat da dang vd phong phu: rdi, Idng it nhdt, Idng nhdt, dam ddc, deo, nhdo, qudnh. Do dd tuy theo yeu cau mdc dp chinh xdc dinh Idpng md chpn phdPng phdp dinh Idpng phu hpp:
Dinh Idpng lien tuc: nguyen lieu ddpc cung cap lien tuc vd khdng ddi theo thdi gian. Cd the xdc dinh Idpng cung cap bang cdch xdc dinh the tich hoac khdi Idpng vdt lieu qua mdy trong mdt dOn vi thdi gian.
Dinh Idpng gidn doan: nguyen lieu ddpc cho vdo cho den khi du Idpng dinh (cdn td ddng), he thdng se ddng dddng nap lieu vd thdo lieu trong may ra. Ldpng cung cap ddpc xdc dinh bang the tich hoac khdi ldpng vat heu trong mdt me cdn.
Cdc he thdng dinh ldpng Hen tuc thddng ddpc che tao ddng bd vdi cdc ddy chuyen sdn xuat cd san ldpng Idn, trong khi dd, thiet hi dinh ldpng gidn doan rat da dang vd dxiac sd dung cho nhieu muc dich khde nhau, ddc biet pho bien trong cdc CO sd sdn xuat, doanh nghiep vda vd nhd. De cd ddpc cdc thiet hi dinh ldpng ndy, mdt sd ca sd Iphai nhap td nddc ngodi hoac td che tao vdi chi phi cao. Bdi bdo ndy trinh bdy thiet ke ca khi vd he thdng dieu khien module dinh ldpng chuan sd dung vit tdi vd load cell, mdt loai thiet bi dinh ldpng ddpc sd dung rat rdng rdi hien nay tren the gidi vd bddc dau ddpc dng dung d Viet Nam trong pong tdc thiet ke vd che tao mdy
2. NGUYEN Lf HOAT D O N G CUA THIET BI DINH LUONG
• • *
Nguyen ly hoat ddng cua thiet bi dinh
ldpng dung load cell (hinh 1) cd the ddpc tdm tat nhd sau: trddc tien nguyen lieu ddpc cap vdo pheu chda cua vit tdi, khi ddng cP hoat ddng dan ddng vit tdi, nguyen lieu se ddpc true vit cudn vdo vd theo cda xd roi vdo pheu cdn va ddpc cdm bien trpng ldpng (load cell) ghi nhdn vd truyen ve bd dieu khiln (hoac PLC). Khi dat den mdt gid tri cdi dat trddc thi bd dilu khien dieu khiln ddng vit tai vd ddng cda xd lai ddng thdi md cda xd cua pheu can cho nguyen lieu rPi ra chuyin den khdu tiep theo hodn tat qua trinh dinh ldpng. Thdng tin cua qud trinh cd thi ddpc hiln thi vd thay ddi qua HMI.
Loadccll ''(."Nj lining
IHI loadoaldyt ngin'mg Loadct-il xuat tin htpu
Amplifier
MojiirloadcaN
PLC Xu ly : T hicu tuAnpMisr.
Oiki khien Cti ciu chip hanh tfcoyeucau
HIHI H i e n l M ^
tri cdn
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Hinh 1: Qui trinh hoat dpng cua he thong can dinh ldpng bang load cell.
2. THIET KE CO KHf 2.1 He thdng vit tai
Thiet ke he thdng vit tdi ddpc trinh bdy d hinh 2. Cl ddy vit tdi ddpc dan ddng bang ddng ca dien dxiac dieu chinh vd cap tdc dp vdi bien tan.
Trddng hpp sd dung hop tdc dp (neu khdng gian cho phep hoac chi sd dung dl dinh ldpng vdi mdt vdi cap tdc dp) cung de ddng lap dat qua khdp ndi ddpc thiet ke san. Vdt lieu 1dm vit tdi vd dng tru thdng vit Id thep khdng gi SUS 316/316L (INOX 316) de d a m ' ^ TAP CHI CO KHf VIET NAM
•
Sd 1+2 (Thang 1+2 nam 2012)chdng oxy hda, dam bdo an todn v | sinh thi^c pham.
Cdc thdng sd cua vit tdi nhd bddc vit S, sd vdng quay n, dddng kinh cdnh D, gdc xodn 0, chieu day cdnh e, chieu ddi L, cdng suat cdn thilt N,... ddpc tinh todn theo [1, 2, 3]. Tinh todn xdc dinh dpng cP, d true, tinh ben,... can cd theo [1, 4]. Thdn vit tdi, khe hd gida vit tdi vd thdn vit tdi ddpc tinh todn, xdc dinh theo [1,3].
CCra xa lieu Xy4anh
Hinh 2: He thong vit tai lieu
Loadcell Loadcell
Pheu can Xylanh Hinh 3: Pheu can vd kit ndi vdi load cell 2.2 Pheu can
Pheu cdn (thdng cdn) Id noi nhdn nguyen lieu td cda xd cua vit tdi vd ddpc kit ndi vdi load cell d l tien hdnh cdn dinh ldpng. Tuy theo khdi ldpng nguyen lieu can dinh ldpng md pheu cdn se cd kich thddc tdPng ling. D l de kit ndi vdi load cell vd cd dxiac sxi on dinh trong qud trinh can, pheu cdn ddpc thilt ke cd hinh dang vudng. Vd tuy theo kich thddc ciia pheu cdn md he thdng cdn dinh ldpng sd dung td 2-4 load cell. Hinh ddng pheu cdn vd cdch kit ndi vdi load cell ddpc chi ra d hinh 3.
2.3 Khung may
Khung mdy ddpc thiet k l d l lap dat he thdng vit tdi lieu, pheu cdn, load cell, tu dieukhien vd mdt sd cdc thilt bi khde. Khung mdy ddd^jW^t ke dii cdng vdng, phu hpp vdi chieu cao W ddng vd Id mdt bd phdn ddc lap. Kit ndi cua^c thilt bi khde len khung mdy ddpc thdc hierfq"^
mdi ghep buldng - dai 6c cho phep ndng cao tinji van ndng ciia thiet k l ciing nhd de ddng choviec dilu chinh.
TAP CHf CO KHf VIET NAM
•
Sd 1+2 (Thdng 1+2 nam 2012)NGHIEN ClJfU - TRAO D6\
J. THIET KE HE THONG DIEU KHIEN 3.2 Thilt bi dieu khien
Modul dinh ldpng chuan vdi day du cdc Thilt bi dieu khiln thdc hien dilu khiln 30 phdn cd kit cau tong thi nhd hinh 4. Khi dda hoat ddng ciia he thdng theo chu trinh nhd dd chi v^do hoat ddng modul can ddpc kit ndi vdi thilt bi ra d hinh 1. Thilt bi dilu khiln se tilp nhdn tin cap lieu dau vdo vd thilt bi lay lieu dau ra. hieu td load cell (da ddpc khulch dai qua ampli-
fier), xif ly, dieu khiln dpng cP dien vd cdc xylanh khi nen dl ddng/md cda nhdn/xa lieu. Ngodi ra, thilt bi dieu khiln cung hiln thi thdng tin qua trinh hoat ddng dinh ldpng len mdn hinh HMI cho phep gidm sdt cung nhd thdc hien dilu khiln theo cdch thdc tdPng tdc.
Cdc phan td dilu khiln sd dung trong he thdng bao gdm: load cell, bd cpng (junction box), khulch dai KM02A, PLC S7-200 CPU 222, modul md rdng sd input/output EM223, modul Analog EM235, giao dien ngddi - mdy HMI TH465-UT [5, 6]. So dd kit ndi cdc phan td dilu khiln ddpc trinh bdy d hinh 6.
Hinh 4: Modul dinh ldpng chuan 3.1 Loadcell
Can cd theo kit cau pheu cdn, kit cau khung mdy, load cell ddpc chpn sii dung Id loai chiu udn (huih 5). Khi hoat ddng cdn, cdc load cell cung cap cdc tin hieu dien dp tdPng dng vdi
; gid tri trpng ldpng md nd cdm nhdn ddpc vd giii din bd cdng (junction box). Bd cdng se phdt sinh : tin hieu ra Id tdng gid tri dien dp do cdc load cell I chuyin din vd ddpc bd khulch dai (amphfier) 1 khulch dai trddc khi tin hieu ddpc chuyin tilp i den cho modul A/D cua PLC.
Amplifier
Input
CPU 222 V
I EM 223 \ EM 235 RS232
IF^SSL,'
f ^^ M
Hmh 5: Load cell va bp khuech dai Hinh 6: So do kit noi ciia cac phan td dieu khien
^
• ! •
TAP CHI CO KHI VIET NAM V Sd 1+2 (Thdng 1+2 nam 2012)
4. KET LUAN
Bdi bdo gidi thieu vi?c thilt kl vd chi tao module dinh ldpng chuan sii dung vit tdi vd load cell. He thdng da ddpc chi tao vd thii nghi?m dat ddpc kit qua nhd mong dpi trong thdc te. Tren cP sd modul dinh ldpng chuan chiing ta cd thi phdt triin dl dinh ldpng nhieu hPn mpt loai nguyen lieu. Hinh 7 trinh bdy h | thdng dinh ldpng 4 loai nguyen lieu khac nhau trong day chuyin sdn xudt mudi tdm ddpc phdt triin tren cP sd modul dinh ldpng chuan va da ddpc triin khai chi tao thdnh cdng (hinh 7). He thdng hoat dpng tdt va dat dp chinh xdc dinh ldpng din 0,25%.
Kit cau cua module dinh ldpng Id dPn gidn cho phep mdt ca sd sdn xuat cP khi trung binh cd thi gia cdng, chi tao ddpc. Cdc thilt bi dilu khiln khde nhd PLC, load cell, cdc phan td dilu khien khde cd thi de ddng mua ddpc tren thi trddng. •
r 1
4
^
• O B
T •
i J mi
J\
Hinh 7: H? thong dinh ldpng 4 loai nguyen lieu diia tren modul dinh ldpng chuan [7]
Tai lieu tham khao:
[1]. Nguyen Nhd Nam, Tran Thi Thanh, May gia cong cO hpc nong san thdc pham, NXB Giao due, 2000.
[2]. A.I.A. XOKOLOV (Nguyen Trpng The, Nguyen Nhd Dung - dich), Co sd thiet ke may san xuat thiic pham, NXB Khoa hpc Ky thuat, 1976.
[3]. Screw Conveyor Corporation, Screw Conveyor Catalog & Engineering Manual, HammiMui, huiiana, 2010.
[4]. Trinh Chat, Le Van Uyin, Tinh toan thilt ke h? dan dpng cO khi, NXB Giao due, 2009.
[5]. Siemens AG, SIMATIC 57-200 Programmable Controller - System Manual, Siemens AG, 1998.
[6]. Hans Berger, Automating with SIMATIC - Controllers, Software, Programming, Data Communication Op- erator Control and Process Monitoring, Publicis Corporate Publishing, 2003.
[7]. Dang Thien Ngdn, Nghien cdu thilt kl, chi tao thilt bi san xuat muoi tdm (cdng suat 80 Kg/ngay), de tai cap Bp, B2010-22-53, 2010.
TAP CHf CO KHf VIET NAM ••• Sd 1 +2 (Thdne 1+2 nam 2012)
