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SINCE IA95 ... EXGELLENGEIN HOISTING ECIUIPMENT

Satisfied customers all over the world attest

to the safety, operational economy and de-

pendability of hoisting equipment engineered

for the site by Nordberg. This bulletin points

out various design features which have given

Nordberg hoists their unequalled reputation

for quality.

The bulletin is also intended to assist in theplanning of hoisting systems of all types and

sizes. Because an extremely wide variety of'

hoisting designs and schemes exists, the bul-

letin does not attempt to cover all the design

details involved in a hoisting system-only the

basic information necessary to arrive ata proper hoist size is included. By following

the step-by-step procedures in pages 12 to 16,

the mine planner, knowing the depth and de-

sired capacity, can determine the proper skip

load, rope size, hoist size, and motor horse-

power.

Page

GLOSSARY OF TERMS.... .......'."""""2,3

HO|ST TYPES ......"""""4,5

SHAFT GUIDE ARRANGEMENTS... ..".....6

wrRE ROPE D4T4............ ......"....-..-.---'7

HolsT DRIVES ................ -......'....""""8

BRAKTNG SYSTEMS...... ..........'..........8' 9

ENGINEERING FEATURES OF

NoRDBERG'Holsrs '10' 11

STEP.BY STEP PROCEDURES FOR DETERMINING

SKIP, ROPE, HOIST AND MOTOR SI2ES....."."...-T2'L6

NORDBERG'S HOISTINGENGINEERING SERVICEln addition to building hoists for any tonnage'

any depth, Nordberg offers a unique engineer-

ing service. Our engineering staff will care-

fully analyze your hoisting problem and submit

detailed recommendations. We'll provide the

answer to a single question or recommend a

complete system for maximum hoisting effi-

ciency, including correlated shaft, conveyance'

and hoist data.

Because of our experience in building all

types and sizes of hoists, you may be certain

that when we recommend a hoist, it will be

perfectly matched to your specific operations'

Please complete the form in the back of this

bulletin and mail it to us' We'll be happy to

furnish you with the information you request'

Ì3.D:E-:G: -'

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t.i..Ë¡},?--

EE-

RfT'ORDBE¡

as those used for shaft sinking.

HEA0SHEAVES are installed on top of headframes andused with either drum hoists or ground mounted Koepehoists. The diameter of the headsheaves is approximatelythe same as the hoist.

HOIST ROPES refer to the main rope or rdpes used forraising the load, regardless of the type of hoist or type ofshaft. These are sometimes referred to as oull rooes.

IDLER SHEAVES are used to support the hoist rope with along span between the hoist and headframe. The numberdepends on the particular installation. ldler sheaves neednot be larger than about 20", depending on spacing andsize of rooe.

J0GGING refers to those times (in automatic or semi-auto-matic hoisting) when it is desired to move the conveyancea very short distance by pushbutton. Normally the "Jog"button is held in the depressed position and the hoistwill move at creep speed until the "jog" button is releasecl.Jogging is sometimes referred to as "lnching", implyinga definite distance moved for each push of the button,but the term "Jogging" is preferable, because it covers avariety of distances.

OVERTRAVEL is the distance above the final stoo limitswitch in the headframe in which a conveyance can bebrought to rest safely in an emergency overtravel stop.Overtravel distances vary considerably and depend onthe normal full speed of the conveyance and the type ofretarding mechanism, if any, used. With automatic hoist-ing there are also several methods of protective slowdownthat affect the risk and therefore the overtravel distancereouired.

ROPE PULL is a term vely often used with two differentmeanings. Sometimes rope pull is defined as the loadattached to the end of the rope, and sometimes as therope pull at the drum (which includes the load attachedto the rope as well as the weight of the rope itself). Whenusing the term rope pull, the loads included should besoecif ied.

SAFETY CATCHES or Safety Dogs or Cage Dogs as they aresometimes called, are mechanisms installed on the manor service cage that will be released when the hoist ropebreaks or when the rope is slack. These safety catches canbe designed to give a definite rate of retarding which isdesirable on high speed hoists. This prevents very abruptand dangerous stops. Serious consideration should begiven to the type of safety catch used.

SLIP (R0PE) occurs when the coefficient of friction or gripis not sufficient to supply the necessary driving or brakingforce on a friction hoist.

SYNCHR0NIZER-every Koepe Hoist requires a synchro-nizer. Since the rope or ropes are not fastened directlyto the drum, it is possible to have relative movement be-tween the drum and rope, such as creep or slip, whichputs the indicating devices out of adjustment. With thehoist at rest the synchronizer may be adjusted manually orautomatically to correct the indicating and safety devices.

TAlt ROPES or balance ropes as they are somet¡mescalled, are used to counteract the weight of the hoistrooes. One end of the tail rooe is fastened to the bottomof one conveyance, passes to the bottom of the shaft,and up the other compartment to the bottom of the otherconveyance. Tail ropes can be used on any hoist to reducepeak power requirements, but they are primarily used onfriction hoists to keep the proper tension ratios.

K0EPE HOIST is a particular type of friction hoist inventedin L877 by Fredrick Koepe. Since it is a relatively new termto this country, it is often referred to as a Koepe FrictionHo¡st.

KOEPE WHEET-since the síze of the drum on the Koeoehoist is considerably smaller either in width or diameterthan the drum on a comparable drum hoist, it is some-times referred to as a wheel.

FLEET ANGLE is the angle the rope makes with the drumas it deviates from perpendicular when winding acrossthe drum. This angle should never exceed lyz". For multi-layer winding the minimum is 0.30,.

Ð

GLOSSARY OF TERMS

part¡ally aPPlied'

CHAIRS (or keps) are supports used to hold the cage ¡nplace because of rope stretch while loading and unloading.They can be stationary or retractable devices dependingon ihe installation. Chairs should be omitted wheneverpossible, but if necessary, due consideration should begiven to how they are used. EOUAtIZERS (R0PE) are used on multi-rope Koepe Hoists.

END L¡FT refers to the position of the hoist with referenceto the shaft compartments. With End Lift the hoist is locat-

ed on a centerline extended thru the two compartments'

FRICTION HOIST is any hoist that uses the principle offriction to drive the rope. There are several types of frictionhoists and therefore, when referring to a particular type'the proper name should be used rather than the general

term of "Friction."

FRONI OR SIDE tlFT refers to the position of the hoist withreference to the shaft compartments. With front or sidelift the hoist is located on a line perpendicular to a center-line extended thru the two compartments.

GROUND SHEAVES are installed near the base of the head-frame for several reasons:

l. When the properfleet angle cannot be attained betweenthe drum and the shaft compartment.

2. When the headframe is extremely high, requiring largeidler stands.

3. When ground or property conditions do not permitproper orientation between the shaft compartmentsànO tfre hoist. The diameter of ground sheaves isapproximately the same as the hoist drum.

COEFFICIENT 0F FRlCTlOtl has particular importance whenreferring to Friction Hoists since it refers to the drivingfriction developed between the hoist rope or ropes andthe friction tread material mounted on the hoist. Sincethe hard wires of the rope actually imbed themselves inthe softer friction material, it is sometimes referred to as

the "Coefficient of Grip." Many types of materials have

been used for the friction treads-wood, leather, rubberand plastic. The allowable coefficients of friction andbear¡ng pressure will vary with the type of friction materialand size of rope and wheel used.

GONTROLS: Automatic-Usually used on a productionhoist. With this type of control, a skip is spotted at theloading pocket and the cycle is initiated by a pushbutton.The hoist will then load, run and unload continuouslyuntil a stop signal is given.

Semi-Automatic - Simi lar to automatic control, except thatthe hoist stops at the end of each cycle and is then starteclagain by pushbutton.

Manual-Requires a hoist operator at all times. He man-ually regulates the amount of electric power and thenecessary mechanical braking. Manual control, ofcourse, requires less eguipment. Automatic and semi-automatic hoists also have provisions for manual control.

CREEP (ROPE) applies to Friction Hoists and describesthe action of the rope or ropes actually creeping over thedrum in the direction of rotation. This is caused by theropes being stretched by the load on the high tensionside and passing over the drum to a lower tension condi-tion. This action is not to be confused with slip.

DEFLECTIOI{ SHEAVE is a'sheave that is sometirnesused with a headf ramemounted Koepe Hoist to d+flect the ropes to the center-line of the compartment. lt isused when the diameter ofKoepe wheel ls larger thanthe center-tocenter distanceof the two shaft compart-ments.

DRUM H0ISI is any hoist that has one end of the rope orropes anchored to the drum and uses the drum for ropestorage.

S¡NGLE DRU* "i?''ttt=;

or ski' in bar-

r single drum hoist can effi-

leveis, since the location of

must be done manuallY for

D¡VIDED SINGLE DRUM HOIST

DOUBLE DRUTü HOIST-ONE DRUM GLUTGHEDAs a service hoist with cage and counterweight' this hoist

can serve several levels Jfficiently' the clutch !t:llf.ll.:q;;i.;k ;ij ;;i m ã nf ot'o óà i io ó"l.o:i

:.ît^"^ t:'^::.il',:l

stretch. This

a

cient hoisting from anY level.

It4t tI i,

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DOUBLE DRUM HO¡ST-BOTH DRUMS GLUTGHED

the mine.

DRUM HOIST KOEPE HOIST

Single Wheel

SINGLE AND MULTI ROPEKOEPE HOISTSingle and n be efficient as

ser;ice hoi ight for single or

multi-level sts with skip and

counrerwer oisting. TheY can

also be effi single level hoist-

ing with skips in balance.

ln order to determine precisely which type of hoist will

suit a particular application, it is necessary to.take thefactors of depth, speed, and load into consideration' Final

selection of ihe correct hoist type should, therefore, takeplace only after a careful engineering analysis has been

äonducteá. Because Nordberg builds both drum and fric-tion hoists, we can recommend and build the type of hoistwhich our engineering staff feels would best su¡t theunique requirements of your operations'

The following table shows the typesof hoists that can be efficiently usedfor some of the more general condi-tions of vertical shafts. These couldalso apply to slope shafts except forthe Koeoe Friction Hoists. Koeoe hoistshave been used on slopes, but this isthe rare exception rather than the rule.

c0N0lil0N

(1) Cage and CounterweightSkip and CounterweightSingle or Multi-level

(2) Skip and SkipSingle Level

(3) Skip and SkiPMulti Level

Single Wheel

Two Wheels(Skip & Countenrveight Each)

Double DrumClutched

.Some mine operatoß prclet a double drum hoisl w¡th one il two clutches for cond¡tîons I and 2, to have add¡t¡onal llex¡b¡l¡ly lor

iõp,e adjustments and rope chang¡ng. fhe ¿rois¿ cost is, oI couße, grealet and must be comparcct with lhe opercl¡onal advantages

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D¡"UM GIROOVIï'TGThele are three types of drum groovìng: helical, parallel

and LeBus

Helical p,rooving is a continuous spiral' givingverysmooth

wiã?iñe w¡ttr n ,¡ngr" rov"'äiiáõã' rt itãs atso bcen used

with multi laYer wlrìdlngs'

Parallel grooving is made up of ìndividual grooves eventy

soac€ verrnao,r- *,ãti irrii tvpe or,c.'99Y11c^ lt ""dfòr multi-layer wind¡ng ä it n"u"i

'=ed for single layer

winding since tne *''" ;;; rn"t ttutt the crest of the

groove to get f rom.one

crossovef'

-1-{ r ¡ l-#\ : f a1iãFù]lrG''

rèi:{s'ûtlT¡G

S.L¡.q.FT GUiÐE,c{ [e F? Á i{ G E lvl E ir!-I- S

Shaft guides are used. in vertical shafts io.keep,l:: t*'Ot'

ã, *",ão cou nrerwe itsh::, U,::f : :iÍ !

tJ':ti:*;lÎilr¡uides are tnac.le oÏ sever

!rìãã1ñ""t are made accordrnglY

TIXED GUIDES

be usecl on the conveyances r tire guide rollers are

rails give a wider bear-

are suPPorted bY ste'lJ guides

n shaPe and size and are

cribed under rvood guides'-usect in the hrgher sPeed

used for the lower sPeeds'

ROPE GUIDES

ancl urllo¿¡ding' tltrl cotrverY

other nteatrs in thesè 'rrcasextler-nes of travel, but a relr

be usecl at intermecliat{l lev

bY wlrrch roPc gtttcles itrt:

ont: ol lltcstr will clt'¡rctrtt

ç -- -jj" 'l¡'

--G|/r.-G-;1--.-

rr:illl:Tlr --l---i RouNo srRANo

'- i-; 6 x l9 cLASs l¡¡PRovED Pl

I sat¡xtrlc ¡

nrÀ I wr¡cHt srRÉllGTH I wElGHlrxînÈs I Las.irr. 'l^lo^n,t"Pt I LBs iFr'

I

: -- T--r. I crq ,?R I l.0Ir,r I 95t/¿ | 129

iu. I zo: 64? i ?91 l!o" i 375 e2o ' t''lrsia I 3 rB 771 | : +o Bs 5' I lly 11:9 I l:',478 ll50iï I :;; s2o I 40; tóró | sos r3so i t"''

' J'| ------l-- I --- ,,n I ouo t;t---l 415 I rB I oaa 1s5 i l::rr, r 5r\ 124 I ssr 136 | tsa lB2 I 1145 15 r24633 t55 | soo 2t2 ì Lh

| 6,;a I6L) | rn t76, I e7/

- 24o

lli-r:i zss Its I ar: !2? l i 2i¿

r aÃr 2o(r I .lto 220 I , 2va

lr,r | 515 124

Itts I S.S t 14 Iz i 672 16c

2tB i zss Its I ar: te7 I i '^',:2Va)1.. I eÃl ?rl(l I VIQ 2?O1"Å QJr I

-L*æ--5-T-::--- -- ..:

ilr,.l,rll.rlr)rr I (lr l(,( k¡'al (:orl r(rlr(" rìlllr¡lrlurlr r'rl'rr "lrt¡¡lrl trr'tl0

i-:::*a':-:^---l'^:-'Ï::::.--'-'----:-:--- --: ----:-----:---î-:---':-:T--"-:l:- -: -::--ì

SAFETY FACTORS FOR DRUM HOISTING ROPES (WhCN HANdIiNg MCN)

--"IT-iLENGTH OF

loPllx IYI_qIL __500 or less500 to 1000

MIN TACTOR Of SAfETY

1000 to 20002000 to 3000'J000 a¡rd over

;':iT::'r--".'--.--*-.-.----1,--+'F-r,çã'--/r '-'ryæ:Ì:t='F' æ-- '--------"''l!---- *.-- -- .

Vi IRE R0l,L- Shown below are some of the various types of w¡re ri)f)cs that are used in mi,ne hoisting

T' , :'.'l l

8.. o

NEW ROPE

B

7

654

MIN TÂCIOR Of SATETYWHEN ROPE MI,JST BE OISCARDED

64 -

5,8504336

Nerr rolátrrA T,rrl Half Lock F ull I ot;k

or B¿l¿net: Rofre Sl¡alt Gu¡de Rope Shall Gurrje RopeRo,rrd Slrand Fl,rtLurred Slr¿nd lldtlerìtid StrindHorstrng Rope Ho¡rlrrrg Rope Horslrrìg Rope

Th¡s table shows the holclrng lorce requirt:rJ for the varlous

ntlmbors of clc¿cl tL¡rns of wire rope on a:'tt:e I drttrn- Tltr: rope

was;l 5/l6" cll¿¡ 6 x 37 wllll flllrc cenlt:r irl p¿ìriìllel glo(lvos

¿lrtrl w¡:; fÌltrils()d ¡'ì lt would lru r)ll ¿l lìolsl (lrllrn lllc r(lsult5

arc l¡asccl on ¿lt;ttlal tests arld c:lc'arly show lhe advant:r¡'irl ol

5OS LBS. multiPle dead Iurns

202 LBS.

7I LBS.26 LBS.

Lockrrri CorlHorstrng RopellorstrnA RopÊ

I 400

I

I

I1

I

354 I LB7 460460 | 24,1

579 | 3307ro i 315

101.0 | s 6s

ilB | 688 155

136 | tza IB2

,,'¿'-dí'r¡ (ll¡-..t1Ì't+t(,'.1|..-_rt"'r.li.: )

THREE TURNS

oo' 400 800PI -LOAD IN LBS

HOIST DRIVES

BRAK¡NG SYSTEMSMINE HOIST BRAKES-The hoist brakes are probably the

äost important part of hoist deslgn The two marn types

;i-b;kes are the jaw and parallel motion tvpes' and these

Ãuu.-uãiiut¡ons. lt is important with any brake that the

brakingOTESSU T

olish thwore fauniform Pressure jaw brake t

ooints. Nordberg jaw brake:wear as parallel motion brakefirst considerat¡on because

BRAKE CONTROL AND SAFETY-There are various brake

ã""iiãr i.¡"Àei using either air or hvdraulics as a control

.åã¡ut. A gravity oaèxup system is a law in most areas'

Sorings, however, naue álso been used to back up the

¡iaxiconttol system should all power fail'

The simplest system is to use a cylinder which raises or

ro*"ri aïeiení on the brake lever' ''tni!:"o?t î'J;?Jìin:

m when the brakesecause of air com-a¡rsystem requlreson or some sort of

On automatic hoists the brakes are requlred to prime just

Ëåioä tt"ip¡ng. Prirning puts a predeterminqd amount

;i;ruk.g'on t'he hoist ðuring the last few feet of creep'

;;i;;i ;î;; the final stop sìgnal is given' final brakins

ü tast and spotting accurate Repetitive accuracy ls

extremelY imPortant.

The following are the available braking schemes:

I Gravlty Primed' Gravity Applied, Pressure Released'

(hydraulic)-

2. Pressure Primed' Pressure Applied,.Pressure Released- w¡th Gravity Backup. (air or hydraulic)

Both of these systems f ulf ill the necessary brakingãqììrã."nt. aná haue been used on Nordberg Hoists'

l,r-JøOãrg normally recommends the first system' however'

t"åãri"ît its simplicity. Three solenoid valves and only

one oressure is used iBthe system'

lsee Erakes section on-P-age 10)

Mine hoists must be equipped with suitable.safety devices

tä mat<e the operation of the hoist as safe as possible'

C"", driu"n from each Nordberg hoist drum.or from the

Xããb. *'r'ã"1 ¡s a Lilly controller-of a type suitable for the

noiti unO this, in cónjunction with the solenoid on the

oiåL.ivr¡no"r, shuts oi the electrical current and appl¡es

the braúes for any of the following reasons:

lf the hoisting speed exceeds normal at any point

lf the operator fails to apply the brakes at the proper

time and rate at the end of travel

lf overwind should occur

lf the operator fails to reverse the hoist after the skip

ä"ä" r''.t-t reached the landing or limit of travel

1.

2.

3.

4

5. lf the Power fails

NORDBERGPRESSURE

UNIFORMJA\^/ BRAKE The unique Nordberg jaw brake features a pivot which is

located lower than that on an ordinary jaw brake. Thiseliminates uneven lining wear by achieving the same uni-form braking pressure which a parallel mot¡on brake pro-

vides Nordberg jaw brakes requìre only one adjustment.

NORDBERG PARALLELMOTION BRAKE

PRESSURE -

PRIME EXHAUST .-SET EKHAUST .--

EMERGENCY EXHAUST "."

Fig. 1

Fie.2

Fig 3

ENGINEERING FEATURES OFNORDBERG HOISTSBRAKES-For most hoisting installations, Nordberg rec-ommends a gravity applied, gravity primed, pressurereleased hydraulic braking system{. This brake operatingscheme is shown in the accompanying drawing. The brakeis applied by a weìght supported at the top of the brakecylinder piston rod. The connection between the brakelever and the weighted cylinder lever is by means of springtension rods.

The hydraulic pressure to release the brakes is furnishedby a variable volume pump unit connected to a weightloaded accumulator. This pressure is connected to thebottom of the brake operating cylinder and is controlledby a brake operating valve operated by a "prime" and "set"solenoid, and an emergency valve operated by an "emer-gency" solenoid.

Fig. I shows the brake in the "off" position. The "prime","set" and "emergency" solenoids are energized, allowingthe brake operating valve to admit oil to the brake operat-ing cylinder. The weight lever moves upward, picking upthe prime lever, which fully releases the brake.

Fig. 2 shows the brake in the "prime" position. The "set"and "emergency" solenoids remain energized. The"prime" solenoid is de-energized, exhausting the brakecylinder. The prime lever moves downward untilthe brakecontacts the brake ring. The movement of the brake weightlever is stopped short of the prime iever by the floatinglever connected to the brake operating valve. The onlyweight applied to the brake atthis point is the prime weightwhich is adjustable by adding or removing weight fromthe prime lever. Thus a variable amount of prime braking '

can be obtained.

Fig. 3 shows the brake in the "set" position. The "prime"solenoid remains deenergized and the "emergency"solenoid remains energized. The "set" solenoid is de+ner-gized, exhausting the brake cylinder. The brake weightlever moves downward to contact the prime lever andadds the brake weight to the prime weight thereby g¡v¡nga full brake application.The following components of the system f unction as safetydevices:

1. Emergency Solenoid-Exhaust cylinder applies the6rale b-y meantõflhe brake weight in case of loss ofpower, overtravel or overspeed.

2. Regulating Valve Connected to Lilly Controller-Regu-

3. Brake Wear Limit Switch-Trips out control circuit,applyrng the brakes when excessive brake block weàrhas occurred-hand reset.

4. "Prime-Set-Emergency" Solenoids-All solenoids en-

,"'i,:3iJl5. rake set or

ect againstpower being applied to motor for any appreciable timewith the brakes applied on automatic hoists.

6. Jammed Conveyance Detector (Koepe Hoists only)-ffid switch,operated byapulley which engages one of the hoist ropes. lt cuts thepower and applies the brakes, bringing the hoist to anemergency stop if a skip should become jammed inthe shaft.

The gravity type oil accumulator with operating cylinderfurnished with each hoist has an umbrella shaped weightof the same design as the brake cylinder weights, propor-tioned to give proper loading for the work¡ng pressure.The oil for operating brakes and clutches is supplied by aselfcontained pressure system. This consists of a weldedsteel reservoir on which the motors and pumps are mount-ed. The reservoir serves as a sump into which the oildrains when released from the cylinders and is the sourceof supply for the pumps. The variable volume vane typepumps are direct connected through flexible couplingstc 'he driving motors. One pump has sufficient capacityfor hoist operation and the other serves as a spare.

Nordberg offers both parallel motion and jaw type brakes.Brake shoes on both parallel motion and jaw type brakesaie steel weldments with asbestos blocks providing a

' friction surface. These asbestos blocks vary from LYz'to2Yz'thickness depending on the brake size' Spring ten-sion rods are used in all brakes, manual or automatic, togive smooth deceleration. Springgraduated braking-this is partimanual control, since it gives thas to the amount of braking being applied.

BEDPTATES-The bedplates, which support the shaft andpinion shaft bearings, are machined where the bearingsare secured, and are drilled for mounting They are fabri-cated from formed plate in the shape of an inverted "U",with reinforcing at the anchoring locations, and are suit-able for mounting on either steel or concrete.

BEARI¡|GS- Drum and pinion shaft bearings are self'aligning, self-lubricating spherical roller bearings.' Therotating rollers dip into oil in the bore of the bearingpedestals. Triple seals in each bearing keep oil in and dustout. Each bearing pedestal is equipped with an oil levelgauge. All main shaft bearing housings are of extra-heavyconstruction.'Sleeve lype bearings can be lurntshed ¡f des¡rcd.

gency stoP,according to the position of the skip or cage in the shaftfor a safe, smooth stop.

lpalenls penct¡ng,

Closeup showing Nordbergclutch assembly.

Tyþical Nordberg oPerator'sconsole. Manual controlson automat¡c hoists canoptionally be located inthe electrical panels.

I-,è-i\

DRIVE SHAFTS-Wheel or drum shafts are open hearth

steel forgings, finished over their entire length. Wher-ever oossible, shafts are made with an integral flange'using body fit bolts in reamed holes to transm¡t torqueto the wheel or drum. This driving flange eliminates key-

ways and resultant stresses which would weaken the shaft'On'large clutched drums the drive is accomplished by

machining a hex section on the shaft. This arrangementalso eliminates keyways.

GEARING-Gears and pinionsare,wherever possible, singlereduction, although more reductions are used in specialcases wnere drum rotation is very slow' Main gears are- ìe hellcã|, annealed, cast steel. Pinions and gears are

experienced. The drums are stress relieved before ma-chining. Parallel, Helical or LeBus grooving is availablefor drLrm hoists. Plastic friction material is supplied withall Koeoe Friction Hoists

CLUTCHES-Clutches are the tooth type, driven from ahex shaped part of the drum shaft. Nordberg clutcheshave a minimum number of moving parts. The clutcha he drum shaftb cylinder. Thec brake release¿ clutch ring isheld to the drum proper with body fit bolts.

OPERATOR'S CONSOLE-A console is furnished to be locat-ed in front of the hoist, or a special control cabinet can be

furnished with the electric control panels for manuallycontrolling the hoist. A micrometer depth indicator whichaccurately indicates the position of the cage in the shaft'and all necessary indicating lights, safety switches, metersand gauges necessary for manual operation are located

on these Þanels.

ERECTIOt{ 0F H0IST-Nordberg Hoists are fully assembled

fied Nordberg field engineers.

FUtL PENETRATION,100% wEtD 80% WELD

STATIC STRENGTHFATIGUE STRENGTHCOST

100100100

83

48

heat treated when necessary. Main gears are attached tothe shafts with split tapered keys. Gear reducers are some-times used with the lower horsepower motors.

GEAR GUARD-Gear guards completely surround the gearand pinions. Pinion shafts have integral throw rings andgears have clampon throw rings. These throw rings effec-tively keep all lubricant within the guards. Bolted cover-plates over the pinions afford inspection of the teethmeshing. A valve on the bottom of the guard allows drain-age of lubricant when necessary.

COUPLINGS-Steel flexible couplings are used betweenthe drive motors and pinions. The couplings absorb shockand compensate for misalignment. One half of each cou-pling is pressed on the pinion shaft and the other half isshipped to the motor manufacturer for pressing onto themotor shaft.

DRUMS-Drums are fabricated in one piece weldmentswhenever size permits. Extremely large drums are madein sections to facilitate shipping. The drum weldmentsconsist of a rolled plate, forming the shell, which is weldedto end plates. The end plates are then connected to a tube(called quill) that is slightly larger than the drum shaft.All of the welds connecting these parts are 100% fullpenetration welds, and like all welds in a Nordberg hoist,are fully tested, using the magnetic particle method. Thesuperiority of this type of weld can be seen ¡n the follow-ing comparison of a full penetration weld with an 80%weld, us¡ng 100 as a basis for static strength, fatiguestrength, and cost:

HOW TO SELECT A HOIST

e¡ven w¡tt serye as ¿ Seneral eu¡de )

GIVEN: Desired capacity (t.p.h.) and depth for vertical shaft

FIND: Skip load, and wire rope sizes, hoist size and motor horse-power

ln s I to know therela caPacitY forlne n in GraPh A'

The as skiP load

decreases, the speed increases to the point where thecycle consists of only acceleration-and retardation, withnô full speed time (approximately 63 f.p's' at 1600 ft ingraph A).

TO FIND SKIP LOAD: Use this equation:ldePth (i.1 ft')- + 0.4 vetocity * 12

velocrty (r.p.s.,SL (in tons) :

capacity (TPH)

I Der¡ved as follows:

cycle time tCl: ffi x skip load (SL) ¡n tons

running time (RT): CT - rest (in sec.) rest - creep time + ¡dle t¡me

nr-99$f-,".t r_--- .ldeprh lyf I ,,*--l-.J(and also x I - Goc¡ti, Ut(f'o^sJ - 2 \ãceleration rate (a) retard rate (rV

Assume creeo and rest t¡me to be 12 seconds total' and a and r râtes to be

2.5 f.p.s' and the equat¡ons reluce to

Rr-ffixsL-12 nr:dïth+o.av

3600 ^. -^ deDrh ^, #*o¿v* tzEquatine ffi x SL - 12: -i' '+ O.¿v or SL = ----j6õ-

tl the resl, ctæp, acceleral¡on and rctad rales are known, these shoulct beused, ralher lhan the above figures

By substituting depth and capacity values, assumlngdifferent velocì-ties, and solving for skip load, plot a sk¡p-load-velocity curve similar to those in Graph A'

GRAPH A-SKI P LOAD/VELOCITY CURVE

FOR 1600 FT. DEPTH

400 ï

2100 l

1800 I

500-l

1200 l

150'l

50

(f .p.s.)

î35-9?

P30côéruo_

Ø20

-10v[). -,;-\=g--\.' -)¿'

20

.2Á,5

4030

., VELOCITYv 0'i :t

g,-

TPH

>/--

iI

.: arl\:S re:reseli the f. - ' :'a /,-='-? Ha S:> r¡ i.le Un;

i,'-:.:' Ci'^": Ih:Se 'J'"gS.-- vrtie !ar,el'o:1s wnlch lnclca

-;1,-., ¿.e nJ: e¿s l-\ esiaI'l thetr a5solute values The

!r,io- .rru" rs tne U. S. Bureau ol Mrnes nrinimum allow-

¿a a r;)eî ffr€1 âr'Ê oeing holstec, Some states have lawst,- z'. et. To'e r,s,C and tne various regülat¡ons change:.-,* ,. -? t:r rrîîe T¡e f¿:tc.S oÍ saÍet)' snown Should be

usec as a g';iJs orìiy and the lav\,s in each area should be

che.keC A !'r¿'. fa.ict o{ saieiy is no subslltule for a Soodt15peCüO. e:)d motntenence proerôm

i0

8

È.7lJJrU)

þeÉ

o<E

4

0 500

The next step ¡s to select the proper skip load. The lcftside of the shaded area of Graph A indicates the portionsof the curves optimum för Koepe Friction Ho¡sts; the rightside shows portions optimum for drum hoists. (Experiencehas shown that the opt¡mum skip load of a Koepe FrictionHoist usually is larger than that of a drum hoist, for thesame tonnage and hoisting depth. By incrèasing the skipload, it is sometimes possible to jump to the next smallestmotor size without greatly increasing the cost of themechanical equipment. With a drum hoist, the costof the mechanicals increases more rapidly than with afriction hoist-hence the different optimum areas.)r

looo ' 1500 2000 2500 3000DEPÍ H (in feet)

3500 4000 4500 5000

From the curve you'have constructed, select the properskip load. Multiply this skip load by .75 to find an approxi-mate skip weight [SW (skip weight): .75 SL].3

T0 FIND ROPE SIZE: Solve this equationt for diameter:

diameter (d) =

(Consult Graph B to determine Kr and K, and factor ofsafety.)

UKATN D-IAUIUXJ

URC KO P

tt:PE

N EOE

1, S A DRUMROPE TYPE Kr l&

Round Strand 41.8 0.00084Flattened Strand 46.0 0.00090Locked Coil 61.6 O.OOI22

2 The cost ol the headframe, skips, load¡ng pockets and ropes enters ¡nto theeconomics when selecting sk¡p loads, but these cost changes are relativelysmall. (Skip s¡zes can be var¡ed w¡th¡n lim¡ts w¡thout changing the shaftsect¡on.) We are not attemptíng to make an econom¡c compar¡son b€tweendrum and Koepe schemes in this bullet¡n-to select one over the other in-volves a complex study which should include the complete hoisting plants.

3 lf your skip weight factor ¡s known, use ¡t rather than 0.75. To determine

þroper lr¡ction hoist sk¡p re¡ght, see Graph C.

4 Derived as follows:

Breaking strength of rope (in tons) -ISL + SW + (wt./ft. of rope x depth)l factor of sâfety

Expressed in terms ol rope d¡ameter, ús¡n8 constants Kr ând K¡, this becomesK, dt: (SL + SW + K, x depth x d:) lactor ol safety.

oeÉ

o

TO FIND M0T0R HORSEP0WER; (RMS HP)

Draw a h.p.itime cycle diâgram similar to Diagram D orDiagram E and label it.

ta : acceleration time (sec.)

tfs : full soeed time (sec.)

tr : retardation time (sec.)

For estimating purposes and simplification, combine tarand taz : ta, and trr and tr2 : 1r' Creep time is not con-sidered in acceleration or retard time.

From your skip load velocity curve, select the full speedvelocity corresponding to the skip load.

Knovùing the velocity, and assum¡ng 2.5 f'p's.2 Íor a andr rates, find ta and tr.

Vta : tr: 25

RMS HP For Drum Hoist

Find the approximate equivalent effective weight (EEW)

on Graoh F.

Using the following steps,s determine h.p. values corres-ponding to various points in h.p./time cyÒle Diagram D.

,_..o. _ TSL x V, SLT x V-.' :3ZZTlãTEilo nr': -*õ-Hp--(SL-R)xV

550

rr,: qååY x .1766

DEPTH (in feet)

TO FIN'0 DRUM DIAMEIER: Consult Graoh C and determrnethe proper D/d ratio number for your hoisting depth. Mul-t¡pty rope diameter (d) by this number to determine drumdiameter (D). Graph C also gives suggested friction hoistTr/Tz ratio and tread oressure limits.T0 FIND FACE WIoTH 0F DRUM Ho¡ST: Select a standardrope d¡ameter corresponding to d. Then solve one of thefollowing equations for face width:For Single Drum: (balanced hoisting, single layer)

face width (inches): S t ogPtft * tUtz¡D

For Double Drum: (single layer)

face width (inches) - S x dgPth * tanD

[S : groove pitch (approximately 1.05d)]

lFor each additionat layer of rope, elimínate the deadturns ll5S or 75) and increase D by 1.7d.J

5(Exolanat¡ons of the abbrev¡at¡ons used in the drum hoist horsepower

eouat¡ons wh¡ch follow,

R - depth x rop€ we¡ght Þ€r tt.

TSL - total suspended load = EEW + SL + 2Sw + 2R

SLB - susD€nded load at bottom of shaft =(SL + R) - (V x ta x rop€ wt per ft.)

SLT - suspended loåd et top of shaft -(SL - R) + (V x tr x rope wl" Per fL)

u.trs- r?E E-085

40

GRAPH C_SUGGESTED DRUM DIAMETER (DYROPEOIAMETER (d) RATIO

ttttttttlttttttttrrrrt ttROUND STRAND AND FLATTENED STRAND-KOEPE

ROUND STRAND AND FLATTENED STRAND_DRUM

SUGGESTED FRICTION HOIST Tr/T¿ RATIO

AND TREAD PRESSURE LIMITS:

SL + Sw + total rgpe wt.

1, = t =1.5t0 1.6

fz 56¡ * total rope wt.

2

' T. ¡Trread Pressure = il*ì[Íìímpe, =

250 to 270 p.s.i.

Rop€ life is increased when largedrums are used. but the cost ofrope replacement in shallow shaftsis small. and smaller drums cånbe used. These curves serye asâ or r¡rlê ôñlv

000 3000 4000

/ rest: creeg t¡me + ¡dle t¡me

E|.o.

tt

HP'+ 2HPJA (peak accelerating h.p.) : HP' + HPz + -- 3

B (full speed h p at endof acceleration period): HPr+ HP?

C (lull speed hp at start of retard period) : HPs* HP;

D (retardatron h.p.): HP, + HP? + HP5 +-2HP6

HP. (h.p required to accelerate -otor.r.o-tor.) - O6A x 1 2

ta

HPp (h p required to retard motor rotor) - - 0'6A ¡ 1'2

E (total h.p. required to accelerate hoist and motor):A+HP¡F (total h.p. required to retard hoist and motor) : D + HP,

CHECK:

The area under the h.p./time cycle Diagram D repre-sents the work done, which equals the load x depthdivided by 550. (eff iciency: 0.85).

lA \ /B+C ..\ lD.\ SLxdepthItxtai *l, z xÍs/+\z',,/: s5x55o

This should check within I to 2%.

Finally, calculate Root Mean Square Horsepower (RMS

HP) for d.c. motor:

RMS HP:.75ta + lfs + .75tr + .5 restr

for induction motor:

RMS HP:.5 ta + tfs + .5tr + .25 rest

170,000

160,000

150,000

140,000

130,000

120,000

I10,000

100,0o0

ó 90,000o; 80,000

u 70.000U

60,oo0

50,000

40,000

30,000

20,000

10,000

0

.TTHP¿ ,J.

ì--IfiP.789101112

DRUM DIAMETER (in feet)

t3 14 l5

rest l*-ta --+--tfs

E,xta*q1{1!9üs*F2xtr

E2 x ta + B'z + c1+ Bc ffs + F2 x trGRAPH T-APPROXIMATE EQUIVALENT EFFECTIVE WEIGHT

REDUCED TO ROPE CENTERFOR DIFFERENT DIAMETER DRUMS

HP"].----- --I^----,ì'HPr ìiA

I

I DTAGR.AM D-H.P./TrME CYCLE

i (Drum Hoist)I : _ :i:.K

{

RMS HP For Friction Hoist

Find the appropriate EEW on Graph F'

R: depth x rope weight per ft. x 2 x no' of ropes

EEW+SL+2SW+R:'TSLUsing the following steps, determine.horsepower values

correlponding to various points in h'p'/time cycle ulagram

E.

TSL X V,áY':322ltalñSLxV

ñr.a: ----==-=- Þþu

Hpz:-"*#h ¡p.:9!]J*.111

A (peak accelerating h.p.) : HP. + HP. + HP'

B (full speed h.P.) : HPs + HPr

C (total retardation h.p.) : HP' + HP. + HP,

HP, (h.p. required to accelerate motor rotor) --'75Alr'2

HP6 (h.p. required to retard motor rotor) - - '75A-x 1'2

D (total h.p. required to accelerate hoist and motor) :A+HPsE (total h.p. required to retard hoist and motor):C+HP6

GHECK:

The area under the h.p./time cycle Diagram. E repre'

iåãd th" *oix oon", which equals the load x depth

divided by 550. (efficiency: '90)r^ r /C .\ SLxdePth(ä x ta) + (B x rfs) + (ã x tr/: ffi5õ-This should check within L Io 2"/"'

Finally, calculate Root Mean Square Horsepower (RMS

HP) for d. c. motor:

RMSHP:ffi**nr-*,for induction motor:

RMS HP

I ron A GtvEN DEPTH AND cAPAclTY,: TnERE ls AN oPTIMUM LoAD

8r r, - lffi-EE

TI

HPzI

I-f-lt,

iI

i.8

E,tt.,

iotìF'aniO,-o 5,L.,ot 1/lits¡74ita

t'3,Ií:. 2

t--a

1., rt

FË

tF

E-.90

" '.il'--