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Broj 1,2012. RUDARSKI RADOVI117

INSTITUT ZA RUDARSTVO I METALURGIJU BOR YU ISSN: 1451-0162KOMITET ZA PODZEMNU EKSPLOATACIJU MINERALNIH SIROVINA UDK: 622

UDK: 621.967.2:622.271 (045)=861

Branislav Rajkovi*, Zoran Ili*, Radomir Mijovi*

POJAVA SUPROTNOSMERNOG KRETANJA TRAKASTOG

TRANSPORTERA ZA RUDU T.109 I SPREAVANJE OVE POJAVE

Izvod

U ovom radu je, na primeru trakastog transportera za rudu na povrinskom kopu Veliki

Krivelj sa kapacitetom 2000 t/h i sa usponom u smeru kretanja materijala, data analiza suprot-nosmernog kretanja trakastog transportera u sluaju njegovog zaustavljanja.

Analiza je uraena raunskim putem metodom obilaska po konturi i predstavlja univerzalnimetod prorauna trakastih transportera iji su rezultati neophodni za izbor ureaja za spre-

avanje suprotnosmernog kretanja trakastog transportera.Takoe su izloeni nain rada i tehnike karakteristike usvojenog ureaja za spreavanje su-

protnosmernog kretanja.Kljune rei: trakasti transporter za rudu, suprotnosmerno kretanje, metod obilaska po kon-

turi, ureaj za spreavanje suprotnosmernog kretanja

*Institut za rudarstvo i metalurgiju Bor

1. UVOD

Suprotnosmerno kretanje trakastihtransportera sa nagibom u smeru kretanjamaterijala predstavlja tetnu pojavu kojamoe da nastane u momentu zaustavljanjatransportera kada pod dejstvom gravi-tacione sile na materijal koji se nalazi natraci transporter tei da se kree u suprot-

nom smeru pri emu moe doi do rasi-panja materijala sa trake i zasipanja ut-ovarnog ureaja materijalom to uzrokujezastoje i gubitke materijala.

Za transport primarno izdrobljene rudebakra na povrinskom kopu Veliki

Krivelj kod Bora od drobilice (poz.T.102.100.2) do otvorenog sklada za ruduprojektovan je trakasti transporter (poz.T.109) [2]. Zahtev investitora u toku izradeprojekta je bio da se proveri mogunost

iskorienja opreme postojeeg trakastog

transportera koji je van funkcije na povrin-skom kopu u Majdanpeku. Za spreavanjesuprotnosmernog kretanja ovog trakastogtransportera bio je predvien ustavljapro-izvoaa Falk sa oznakom 1105NRT. U

svrhu provere da li ovaj ureaj zadovoljavau novim radnim uslovima uraen je pro-

raun suprotnosmernog kretanja trakastogtransportera T.109 metodom obilaska pokonturi.

2. TEHNIKI OPIS TRAKASTOG

TRANSPORTERA T.109

Trasa trakastog transportera data jeslici 1.

Tehnike karakteristike transportera:

1. Podaci o materijalu

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1.1. Vrsta materijala: ruda bakra1.2. Maksimalna dimenzija komada:

[ ]mma 250max =

1.3. Nasipna gustina:

=3

1600m

kg

1.4. Ugao prirodnog pada materijala u

kretanju: [ ]o20= 2. Podaci o transporteru

2.1. Proizvoa: FOD Bor2.2. Kapacitet transportera:

=h

tQm 2000

2.3. Duina transportera:

[ ]mL 076,466=

2.4. Brzina transportera:

=s

mv 8.3

2.5. Uslovi rada transportera: Rad vanprostorije, vlaan vazduh

Trakasti transporter (vidi sliku 1) je sagumenom trakom sa elinim uadima St1250 irine 1200 mm koritastog poprenogpreseka sa tri nosea valjka pod nagibomod 36 na radnoj grani i sa dva povratna

valjka pod nagibom od 10 na povratnojgrani.

Konstrukcija transportera se sastoji odutovarne stanice, standardnih sekcija iistovarno-pogonsko-zatezne stanice.

Utovarna stanica sastoji se od noseekonstrukcije, utovarnog levka, povratnog

bubnja, nose

ih amortizacionih valjaka ipovratnih valjaka.Standardnih sekcija ima dva tipa koji

se razlikuju u duinama tako da su duesekcije (tip A) predviene na ravnimdelovima trase transportera a krae (tipB) u krivinama.

Istovarno-pogonsko-zatezna stanica sesastoji od nosee konstrukcije (strele)

transportera, istovarnog bubnja, pogonskihbubnjeva, otklonskih bubnjeva i zateznog

bubnja, pogona transportera, ureaja zazatezanje i noseih i povratnih valjaka.

Pogon transportera je preko dva bubnjai sastoji se od dve identine pogonskegrupe koje se sastoje od elektromotora,spojnice izmeu elektromotora i reduktora,reduktora, spojnice izmeu reduktora ipogonskog bubnja i samog pogonskog

bubnja.Zatezanje trake vri se preko zateznog

bubnja smetenog u okviru istovarno-pogonsko-zatezne stanice koji se zateetegom pomou ueta i sistema uetnjaa.

Istovar se vri preko istovarnog bubnja-bubnja za odbacivanje koji se nalazi na

gornjem kraju trakastog transportera.Za spreavanje suprotnosmernog kreta-nja trake transportera predviena je konicakoja je smetena na istovarnom bubnju.

Za brisanje trake od naslaga materijalapredviena je struna guma na istovarnombubnju.

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Sl. 1.Trakasti transporter T.109

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3. PRORAUN SUPROTNO -

SMERNOG KRETANJA

TRAKASTOG TRANSPORTERA

T.109

1. Proraun ima za svrhu odreivanjepotrebnog koionog momenta ureaja zaspreavanje suprotnosmernog kretanja

trakastog transportera smetenog navratilu bubnja za odbacivanje preko kogase obavlja istovar materijala na krajutrakastog transportera.

Proraun se vri metodom obilaska pokonturi prema [1] za suprotnosmerno kre-tanje transportera. Karakteristine take ukojima se raunaju sile u traci date su na

slici 1. Proraun poinje od take 3 u kojojtraka pri suprotnosmernom kretanjunailazi na zatezni bubanj i u kojoj je silauslovljena teinom zateznog tega. Pro-raun se odvija od take 3 od take 21 usmeru koji odgovara suprotnosmernom

kretanju trake, a od take 4 od take 20 usuprotnom smeru. Razlika izraunatih sila

u takama 20 i 21, koje predstavljaju takenailaska i silaska trake bubnja za odba-civanje na ije vratilo se montira koioniureaj, odreuje veliinu koionog mo-menta.

2. Sile optereenja po dunom metrutransportera

2.1. Od transportovanog tereta

=

=

m

N

m

N

v

gQq mter 211,1434

6,3

2.2. Od teine obrtnih delova rolniradne grane

=

= m

N

m

N

l

gm

qArgr

Argr

Argr 9,228..

..

..

=

=m

N

m

N

l

gmq

Brgr

BrgrBrgr 35,343

..

....

2.3. Od teine obrtnih delova rolnipovratne grane

=

=m

N

m

N

l

gmq

Apgr

ApgrApgr 857,127

..

....

=

=m

N

m

N

l

gmq

Bpgr

BpgrBpgr 785,191

..

....

2.4. Od teine trake

=

=m

N

m

Ngmq trtr 326,241

gde su:

[ ]kgm rgr 28. = - masa obrtnih delova

noseih rolni

[ ]ml rgAr 2,1. = - rastojanje izmeu

noseih rolni tipa A

[ ]kgm pgr 1,39. = - masa obrtnih

delova povratnih rolni

[ ]ml pgAr 3. = - rastojanje izmeu

povratnih rolni tipa A

[ ]ml pgBr 2. = - rastojanje izmeu

povratnih rolni tipa B

[ ]ml rgBr 8,0. = - rastojanje izmeu

noseih rolni tipa B

[ ]kgmt 6,24= - masa trake po duini

trake3. Proraun sila u traci u karakteristinim

takama transportera:

[ ]NFF zz 6215223 =

=

gde su:

[ ]NFz 130847= zatezna sila

[ ]= 95,0z stepen korisnosti

zateznog ureaja

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[ ]NkFF p 6,6525932 ==

[ ]NkFF p 3,6871821 ==

[ ]NkFF p 4,72360123 ==

[ ]NkFF p 5,761952322 ==

[ ]NkFF p 9,802332221 ==

[ ]Nk

FF

p

4,192.5934 ==

[ ]NWFF 2,580715445 ==

[ ]N

wLqwLqW Apgrtr

2,1121

54..5454

=

=+=

[ ]NWFF 7,561616556 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

5,190965..

656565

=+

++=

[ ]NWFF 489327667 ==

( )[ ]NwLq

wLqW

Apgr

tr

9,7229

sincos

76..

7676

=+

++=

[ ]NWFF 2,467468778 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

8,218587..

878787

=+

++=

[ ]NWFF 1,440019889 ==

( )

[ ]NwLq

wLqW

Apgr

tr

1,2745

sincos

98..

9898

=+

++=

[ ]NWFF 1,42395109910 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

1606109..

10989109

=+

++=

[ ]NWFF 1,4093911101011 ==

[ ]NwL

qwLqW Apgrtr

14561110

..11101110

=

+=

[ ]Nk

FF

p

6,389891112 ==

[ ]NWFF ut 6,389891213 =+=

[ ]NWFF 8,3721014131314 ==

[ ]Nw

LqwLqW Apgrtr

8,1778

1413..14131413

=

+=

[ ]NWFF 5,3928315141415 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

7,20721514..

15141514

1514

=+

+

+=

[ ]NWFF 5,4879316151516 ==

( )( )

[ ]NwLqwL

qqW

Argr

tertr

9510

sincos

1615..

1615

1615

=+

+

+=

[ ]NWFF 4,5748117161617 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

9,86871716..

17161716

1716

=+

+

+=

[ ]NWFF 6,9130518171718 ==

( )( )

[ ]NwLqwL

qqW

Argr

tertr

2,33824

sincos

1817..

1817

1817

=+

+

+=

[ ]NWFF 9,9672719181819 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

3,54221918..

19181918

1918

=+

+

+=

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[ ]NWWFF str 7,8834820191920 =+=

( )

[ ]N

wLqwL

qqW

Argr

tertr

2,7791

2019..2019

2019

=

=+

+=

gde su:

[ ]pk - koeficijent poveanja sile

zatezanja pri obavijanju doboa

[ ]= 04,0w koeficijent otpora trak.

transportera za oluasti profiltrake i rad spolja

[ ]mL ba duina karakteristinedeonice

[ ]o ugao nagiba karakteristinedeonice

[ ]mL bHa duina karakteristine

deonice u horizontalnoj projekciji

[ ]mL bVa duina karakteristine

deonice u vertikalnoj projekciji

[ ]NWut 0= otpor na utovarnom delu

trakastog transportera

[ ]NBWstr 12490490 == - otpor

strune gume brisaa

Potrebna sila koenja na bubnju zaodbacivanje izraena je jednainom:

[ ]NFFFk 8,81142120 ==

Moment koenja na sporohodomvratilu bubnja za odbacivanje dat jejednainom:

[ ]NmDFM kkk 6,56292

==

gde je:

25,1=k stepen sigurnosti koenja

[ ]mD 11,1= spoljni prenik bubnja

za odbacivanje

4. DISKUSIJA PRORAUNA

Proraunom dobijena pozitivna vred-

nost sile koenja pokazuje da je moguesuprotnosmerno kretanje trakastog trans-

portera pri njegovom zaustavljanju.Da bi se spreilo suprotnosmerno kre-

tanje trakastog transportera predvien jeodgovarajui ureaj (vidi sl. 2) koji se sastoji

od nepokretnog spoljnjeg prstena koji jepreko poluge fiksiran za spoljnu konstruk-

ciju i pokretne glavine sa kosim ispustimaizmeu kojih se kotrljaju rolne smetene uodgovarajuem kavezu vezanom prekoopruga za obrtnu glavinu. U toku kretanjatrake u radnom smeru rolne se slobodnokotrljaju po spoljnjem prstenu dok pri su-protnosmernom kretanju dolazi do njihovog

zaklinjavanja izmeu odgovarajue profili-sane povrine glavine i spoljnjeg prstena.Obrtni moment koenja se preko spoljnjegprstena i poluge prenosi na spoljnu kon-strukciju (vidi sl. 3).

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Sl. 2.Princip rada ureaja za spreavanje suprotnosmernog kretanja trakastog transportera

Sl. 3.Ureaj za spreavanje suprotnosmernog kretanja trakastog transportera ugraen na

vratilu bubnja za odbacivanje

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5. ZAKLJUAK

Prema katalokim podacima proizvo-aa Falk [3], ureaj za spreavanje su-protnosmernog kretanja trakastog trans-portera sa oznakom 1105NRT ima mak-simalni dozvoljeni koioni moment od60975 Nm koji je vei od potrebnog, to

znai da postojei ureaj za koenje zado-voljava.

Iako sporohodi ureaj za zaustavljanjetrakastog transportera pri suprotno smer-nom kretanju, obraen u ovom radu, pred-stavlja samo jedan nain reavanja ovogproblema, uz ureaje za koenje saskakavicom i brzohode ureaje za ko-

enje, on ima nesumnjive prednosti presvega u jednostavnoj montai, tihom ipouzdanom radu i dugom radnom veku.

6. LITERATURA

[1] S. Toi: Proraun maina neprekidnogtransporta i dizalinih ureaja, Mainskifakultet Beograd, 1994. god.

[2] Z. Ili i B. Rajkovi: Glavni mainskiprojekat transportnog sistema zapovezivanje drobilice iz sistema za

rudniku otkrivku sa odlagaem zaprimarno izdrobljenu rudu napovrinskom kopu Veliki Krivelj

[3] Katalog: Falk True Hold Low SpeedBackstops

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No 1, 2012. MINING ENGINEERING125

MINING AND METALLURGY INSTITUTE BOR YU ISSN: 1451-0162

COMMITTEE OF UNDERGROUND EXPLOITATION OF THE MINERAL DEPOSITS UDK: 622

UDK: 621.967.2:622.271(045)=20

Branislav Rajkovi*, Zoran Ili*, Radomir Mijovi*

PHENOMENON OF REVERSAL MOTION OF BELT CONVEYOR FOR

ORE T.109 AND PREVENTION OF THIS PHENOMENON

Abstract

This paperwork gives an analysis of reversal motion of the belt conveyor in the case of its

stoppage in the example of a belt conveyor for ore at the open pit Veliki Krivelj, with capacityof 2000 t/h with inclination in material transport direction.

The analysis was made by the calculation procedure using the contour bypass method,which is a universal calculation method for conveyor belt calculation, whose results are indispen-

sable for the selection of backstopping device of belt conveyor.Also, the principal of operation and technical characteristics the selected backstopping device

are stated.Key words: belt conveyor for ore, reversal motion, contour bypass method, backstopping

device

* Mining and Metallurgy Institute Bor

1. INTRODUCTION

Reversal motion of belt conveyors

with inclination in material transportationdirection is a harmful phenomenon whichmay occur at the moment of stoppage thebelt conveyor when, under the influenceof gravitational force on the material on

belt, the belt conveyor tends to move inopposite direction whereby the effusion of

material from the belt conveyor may occuras well as the backfilling of loading deviceby material, causing intermissions andmaterial loss.

The belt conveyor was designed fortransport of primary crushed copper ore at

the open pit Veliki Krivelj in Bor fromthe crusher (pos. T.102.100.2) to the openstorage for ore [3]. The request of investorduring designing was to check the possibil-ity of usage the existing equipment of a

similar belt conveyor, which was out of

operation at the Majdanpek open pit. Thebackstopping device, made by Falk withlabel 1105 NRT, was predicted in order toprevent the reversal motion of the beltconveyor. For the purpose of this deviceverification in the new operating condi-

tions, the calculation of reversal motion ofthe belt conveyor T.109 was done using

the contour bypass method.

2. TECHNICAL DESCRIPTION OF

BELT CONVEYOR T.109

The route of the belt conveyor isshown on figure 1.

Technical characteristics of beltconveyor:

1. Material data

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1.1. Sort of material: copper ore1.2. Maximum size of lumps:

[ ]mma 250max =

1.3. Bulk density:

=3

1600m

kg

1.4. Surcharge angle in motion:

[ ]o20= 2. Belt conveyor data

2.1. Manufacturer: FOD Bor

2.2. Capacity:

=h

tQm 2000

2.3. Length: [ ]mL 076.466=

2.4. Speed:

=s

mv 8.3

2.5. Operating condition: Operationoutside the room, humid air

Belt conveyor (Figure 1) has a rubberbelt with steel cords St 1250, width of1200 mm, and trough cross section madeof three carrying rolls with trough idlerangle of 36 on carry side and two return

rolls with trough idler angle of 10 on re-turn side.

Construction of belt conveyor includesa loading station, standard sections anddischarge-drive-take up station.

Loading station consists of a bearingconstruction, charging chute, tail pulley,

carrying amortizing rolls and return rolls.

There are two types of standard sec-tions which differ in length, so that longersections (type A) are predicted at

straight segments of the belt conveyorroute, while shorter sections (type B)are predicted at bends.

Discharge-drive-take up station con-sists of a bearing construction (arrow),discharge pulley, drive pulleys, snap pul-

leys and take up pulley, conveyor driveunit, take up device and carrying and re-

turn rolls.Conveyor driving is obtained by

means of two pulleys, and it consists oftwo identical driving units, each consist-ing of an electric motor, a coupling be-tween the motor and gear unit, the gearunit, coupling between the gear unit anddrive pulley and a drive pulley itself.

Belt tension is obtained taking up pul-ley placed within the discharge-drive-takeup station, tightened by counter weightusing a rope and system of pulley blocks.

Discharge is done by discharge pulley-unloading pulley, placed at the upper endof belt conveyor.

To prevent the reversal motion of beltconveyor, the backstopping device is pre-dicted, placed on a discharge pulley.

A scraping rubber, mounted on a dis-charge pulley, is predicted for cleaning thematerial layer off the belt.

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Fig. 1.Belt conveyor T.109

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3 .CALCULATION OF REVERSAL

MOTION OF THE BELT

CONVEYOR T.109

1. Calculation was aimed to determinethe brake torque required for belt con-veyor backstopping device, mounted onthe shaft of discharge pulley serving for

material unloading at the end of belt con-veyor.

Calculation is done using the contourbypass method towards [1] the reversalmotion of belt conveyor. Characteristicpoints, in which the tension forces in beltare calculated, are given in Figure 1. Cal-culation starts at point 3 at which the belt,

during the reversal motion, ascends takeup pulley and the tension force is deter-mined by the weight of counter weight.The calculation is done from point 3 topoint 21 in the direction corresponding tothe reversal motion of the belt, whilst the

calculation from point 4 to point 20 isdone in opposite direction. The difference

between calculated tension forces at points20 and 21, representing ascending anddescending points of the belt at dischargepulley on whose shaft the backstoppingdevice is mounted, determines the value ofthe brake torque.

2. Loads per meter of the belt length

2.1. From transported material

=

=

m

N

m

N

v

gQq mter 211.1434

6.3

2.2. From the weight of rotary parts ofcarry side rolls

=

= m

N

m

N

l

gm

qArgr

Argr

Argr 9.228..

..

..

=

=m

N

m

N

l

gmq

Brgr

BrgrBrgr 34335

..

....

2.3. From the weight of rotary parts ofreturn side rolls

=

=m

N

m

N

l

gmq

Apgr

ApgrApgr 857.127

..

....

=

=m

N

m

N

l

gmq

Bpgr

BpgrBpgr 785.191

..

....

2.4. From the belt weight

=

=

m

N

m

Ngmq trtr 326.241

where:

[ ]kgm rgr 28. = mass of rotary parts

of carrying rolls

[ ]ml rgAr 2.1. = distance between car-

rying rolls type A

[ ]kgm pgr 1.39. = -mass of rotary parts

of return rolls

[ ]ml pgAr 3. = -distance between return

rolls type A[ ]ml pgBr 2. = -distance between return

rolls type B

[ ]ml rgBr 8.0. = -distance between car-

rying rolls type B

[ ]kgmt 6.24= belt mass per meter

3. Calculation of tension forces atcharacteristic points of belt conveyor:

[ ]NF

F zz 621522

3 =

=

where i:[ ]NFz 130847= tension force

[ ]= 95.0z efficiency of take up

device

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[ ]NkFF p 6.6525932 ==

[ ]NkFF p 3.6871821 ==

[ ]NkFF p 4.72360123 ==

[ ]NkFF p 5.761952322 ==

[ ]NkFF p 9.802332221 ==

[ ]Nk

FF

p

4.192.5934 ==

[ ]NWFF 2.580715445 ==

[ ]N

wLqwLqW Apgrtr

2.1121

54..5454

=

=+=

[ ]NWFF 7.561616556 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

5.190965..

656565

=+

++=

[ ]NWFF 489327667 ==

( )[ ]NwLq

wLqW

Apgr

tr

9.7229

sincos

76..

7676

=+

++=

[ ]NWFF 2.467468778 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

8.218587..

878787

=+

++=

[ ]NWFF 1.440019889 ==

( )

[ ]NwLq

wLqW

Apgr

tr

1.2745

sincos

98..

9898

=+

++=

[ ]NWFF 1.42395109910 ==

( )[ ]NwLq

LwLqW

Bpgr

VHtr

1606109..

10989109

=+

++=

[ ]NWFF 1.4093911101011 ==

[ ]NwL

qwLqW Apgrtr

14561110

..11101110

=

+=

[ ]Nk

FF

p

6.389891112 ==

[ ]NWFF ut 6.389891213 =+=

[ ]NWFF 8.3721014131314 ==

[ ]Nw

LqwLqW Apgrtr

8.1778

1413..14131413

=

+=

[ ]NWFF 5.3928315141415 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

7.20721514..

15141514

1514

=+

+

+=

[ ]NWFF 5,4879316151516 ==

( )( )

[ ]NwLq

wL

qqW

Argr

tertr

9510

sincos

1615..

1615

1615

=+

+

+=

[ ]NWFF 4.5748117161617 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

9.86871716..

17161716

1716

=+

+

+=

[ ]NWFF 6.9130518171718 ==

( )( )

[ ]NwLqwL

qqW

Argr

tertr

2.33824

sincos

1817..

1817

1817

=+

+

+=

[ ]NWFF 9.9672719181819 ==

( )( )

[ ]NwLqLwL

qqW

Brgr

VH

tertr

3.54221918..

19181918

1918

=+

+

+=

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[ ]NWWFF str 7.8834820191920 =+=

( )

[ ]N

wLqwL

qqW

Argr

tertr

2.7791

2019..2019

2019

=

=+

+=

where:

[ ]pk - coefficient of tension force

increase due to belt windingaround pulley

[ ]= 04,0w resistance coefficient of

belt conveyor for trough belt pro-file and outside operation

[ ]mL ba length of specific section

[ ]o inclination angle of specificsection

[ ]mL bHa length of specific section

in horizontal projection

[ ]mL bVa length of specific section

in vertical projection

[ ]NWut 0= resistance on the loading

part of belt conveyor

[ ]NBWstr 12490490 ==

resistance of scraping rubber ofthe cleaner

The required brake force, at dischargepulley, is expressed by equation:

[ ]NFFFk 8.81142120 ==

Brake torque on low speed shaft ofdischarge pulley is given by equation:

[ ]NmDF

M kkk 6.56292

=

=

where:

25.1=k braking efficiency

[ ]mD 11.1= outer diameter of

discharge pulley

4. DISCUSSION OF CALCULATION

The obtained positive value of brake

force by calculation shows that the rever-sal motion of belt conveyor is possible atits stoppage.

To prevent reversal motion of belt

conveyor, a suitable device is predicted(Figure 2) which consists of a stationary

outer race, fixed to the outer constructionwith a lever, and a rotating inner cam withramps, between which rollers turn placedin a suitable cage attached via springs tothe rotating inner cam. During the beltmotion in working direction, the rollersturn freely over the outer race while they

are wedged between adequately profiledsurface of cam and outer race at reversalmotion. The brake torque is transferred viathe outer race and lever to the outer con-struction (Figure 3).

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Fig. 2. The operation principle of the belt conveyor backstopping device

Fig. 3. The assembled backstopping device of belt conveyor on discharge pulley shaft

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5. CONCLUSION

According to the manufacturer Falkcatalogue data [3], the backstopping de-vice with label 1105NRT has maximumallowable brake torque of 60975 Nm,which is higher than the needed one,meaning that the existing backstopping

device satisfies.Although the low speed backstop de-

vice, explained in this paperwork, repre-sents only one way of solving this prob-lem, it has the undoubted advantagesalong with backstop devices with pawland high speed backstops, first of all insimple assembling, quite and reliable op-

eration and long operating life.

6. REFERENCES

[1] S. Toi: Calculation of ContinuousTransport Appliances and LiftingDevices, Faculty of MechanicalEngineering, University of BelgradeBelgrade, 1994 (in Serbian);

[2] Z. Ili, B. Rajkovi: Detail MechanicalDesign of Transport System forConnecting the Crusher of MineOverburden System with Polar Stackerfor the Primary Crushed Ore at theOpen Pit Veliki Krivelj, Mining andMetallurgy Institute, Bureau MEGA,Bor, 2011 (in Serbian);

[3] Catalogue: Falk True Hold Low SpeedBackstops.

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