Wiredrawing大中拉培训教材

1、the power of forwardthinkingbuilding the futureconfidentialwire drawingvermeulen dirkr#klpaa/06/1972wire drawing basics page2/29vermeulen dirk 01/05confidentialbasic principle to reduce the diameter of the wire: ! the volume(mass) of the wire remainsthe length increasesthe diameter is reducedv0 = v1

2、v0v1d0d1l0l13wire drawing basics page3/29vermeulen dirk 01/05confidentialflow of the material4wire drawing basics page4/29vermeulen dirk 01/05confidentialhow the deformation is done in a diehere there is the deformation but also frictionpowerforce5wire drawing basics page5/29vermeulen dirk 01/05conf

3、identialpower all used power is converted into:90 to 95% to the deformation of the wire = heat10 to 5% in residual stressesa drawing machine is huge heat exchangercooling is the name of the game6wire drawing basics page6/29vermeulen dirk 01/05confidentialdeformationinhomogeneousdeformation,shear los

4、s,redundant work 2friction loss contact lengthhomogenous deformation reduction7wire drawing basics page7/29vermeulen dirk 01/05confidentialdeformationinhomogeneousdeformation,shear loss,redundant work 28wire drawing basics page8/29vermeulen dirk 01/05confidentialdrawing force graphdrawing force: mod

5、el for drawing 0.32 to 0.30ht010203040506070801.52.53.54.55.56.57.58.59.510.511.5semi die angle force nhomogeneousfriction lossshear losstotal.pdfboekje rv draadtrekken.pdfmore9wire drawing basics page9/29vermeulen dirk 01/05confidentialpowerto have sufficient force to draw the wire through the die

6、we need powerpower : comes from electric motorhow much power?depends on:oamount of deformation(= reduction or elongation)5.5 to 4.75 versus 5.5 to 5.00mmostrength of the wirehica (0.80%c) versus loca (0.05%c)ospeed1m/sec versus 20 m/secofriction in the die ( lubricant, coating die angle.)10wire draw

7、ing basics page10/29vermeulen dirk 01/05confidentialexamples wire rod 5.5mm drawn to 4.75mm 2 m/secloca (0.10%c )needs : 8.5kwhica (0.80%c) needs :22.5kw wire 2.00mm drawn to 1.80 20m/secloca (0.10%c) needs : 16.7kwhica (0.50%c) needs : 31.9 kw11wire drawing basics page11/29vermeulen dirk 01/05confi

8、dentialpower 9kw ?= 12wire drawing basics page12/29vermeulen dirk 01/05confidentialpower 32kw=13wire drawing basics page13/29vermeulen dirk 01/05confidentialpower drawing 2mm loca from 6.5mm 15m/sec (= 54km/h or 34miles/hourneeds : 175kw net or 235 horse power14wire drawing basics page14/29vermeulen

9、 dirk 01/05confidentialmastering the drawing process is mastering the wire temperaturesince a too high wire temperature destroys the lubricant film and the wire properties15wire drawing basics page15/29vermeulen dirk 01/05confidentialwire temperature2. deformation temperature (homogeneous + redundan

10、t)- % reduction- die angle- % carbon and tensile3. friction temperature- contact length ( die angle bearing length)- lubricant, coating- speed1. temperature of the wire before the die= cooling of the wire on the previous passthe temperature of the wire after the die is the sum of16wire drawing basic

11、s page16/29vermeulen dirk 01/05confidential1. cooling on the capstantemp top : 80c(176f)temp bottom 160c(320f)die box5% of the wire heatgoes to the die cooling60 to 70% of the wire heatgoes the capstan cooling10 to 15% of the wire heatgoes to the air10% of the wire heatgoes with the wire to the next

12、 pass17wire drawing basics page17/29vermeulen dirk 01/05confidential1.cooling on the capstan1. temperature measurementtemperatures to be measured with ir temperature meterwater flow to be measured with bucket and chronometertemp top : 80c (176f)temp bottom 160c(320f)water supply from cooling circuit

13、,min 1 bar pressuretemp2cbucket of 10lmeasure the time tillits fullcalculate water flowdelta temp 2cdie boxtemp : only 19kw cooling possible problem : wire temp will be too high20wire drawing basics page20/29vermeulen dirk 01/05confidentialpractical examples : total machinekoch hlohovec 588mmintempe

14、rature water out?ctotal machine water flow15.6 m/h26 l/min per blockis kw to cooling water36.54574 kwor 3.7kw per blocktheoretic total power40.05338 kwmeasured total power47.9 kw%to water f( measured)76.29591 %koch hlohovec 765mmineffect of speed?temperature water out18.4 ctotal machine water flow17

15、 m/h28.3 l/min per blockis kw to cooling water37.50389 kwor 3.75kw per blocktheoretic total power52.11027 kwmeasured total power59.4 kw% to water f(measured)63.13786 %jupiter 15pass petrovicectotal machine water flow13 m/h14.4 l/min per blockis kw to cooling water89 kwor 5.9kw per blocktheoretic tot

16、al powerkwmeasured total power137.9 kw% to water f(measured)64.54 %frigerio 15 pass petrovicetotal machine water flow13 m/h14.4 l/min per blockis kw to cooling water89 kwor 5.9kw per blocktheoretic total powerkwmeasured total power133 kw% to water f(measured)66.92 %capstans 400mmcapstans 550-450mm21

17、wire drawing basics page21/29vermeulen dirk 01/05confidentialwire temperatures on koch machine2,90 to 0,895 - 0,70%c patented02040608010012012345678910passtemperature cbottom 588 m/mintop 588 m/minbottom 765 m/mintop 765m/minhigher speed = more power ; cooling capacity remains the same ; hence highe

18、r temperatures22wire drawing basics page22/29vermeulen dirk 01/05confidentialresults of power and cooling measurementspassfrigerio*jupiterfrigerio*jupiter17.437.1779%82%26.867.7186%77%37.317.3781%80%47.317.781%77%57.567.778%77%69.939.9459%59%79.499.7462%61%810.6210.0456%59%910.19.6758%61%1010.489.79

19、56%60%119.7710.9360%54%128.739.6468%61%138.969.7266%61%148.828.1567%72%159.9712.6359%47%results of measurements : comparison frigerio - beng- measured power- in average 5.9kw to cooling =results in %remark : no difference was made for the capstan size herepower not good distributed : too much power

20、on the small capstans23wire drawing basics page23/29vermeulen dirk 01/05confidentialwire temperatures : influence of dust extraction0204060801001201401601802000246810121416frigeriojupiterfrigeriojupiter6.5 loca to 1.05mm 1650 m/minfrigerio : 8 pass 560 others 460jupiter : 10 pass 550 others 450heat

21、is accumulated in the wire24wire drawing basics page24/29vermeulen dirk 01/05confidentialwire temperatures : no dust extraction0204060801001201401601802000246810121416geen afzuigingafzuigingafzuiginggeen afzuigingtemperatures higher if dust extraction is switched of25wire drawing basics page25/29ver

22、meulen dirk 01/05confidentialinfluence of forced air coolingwire temperatures top block305070901101301501701234567891011passc1.32 730m/min air on1.32730m:in air off1.81730 m/min air on1.81730m/min airoff2.21480m/min air on2.21580m/min air off1.32 0.50%c1.81 0.65%c2.21 0.70%c26wire drawing basics pag

23、e26/29vermeulen dirk 01/05confidentialinfluence of air cooling on mech. propertiesmechanical propertiesair on air offair on air offair on air off mm1.321.321.811.812.212.21rm n/mm199620061960199819312043a %2.061.821.021.031.641.34at %3.022.791.972.012.592.37z %53.353.653.550.950.648.3nb141313.51321.

24、513.5nt39 (1a)37.5 (1a)36 (1a)35 (1a)37.5 (1a)33 (2a)rp/rm %83.985.587.69184.790no air cooling = increase of rm + somewhat lower ductilityfrig 614 : no air cooling and higher speed = not acceptable resultsfrig 612frig 613frig 61427wire drawing basics page27/29vermeulen dirk 01/05confidentialconclusi

25、ons about capstan cooling if used power is higher then cooling capacity the heat is accumulated into the wire hence drawing problems + poor mechanical properties therefore die series should be calculated taken into account the cooling capacity of the capstans. smaller capstans have less cooling capa

26、city damaged water seals in the narrow gap system, incrustations etc. reduce the cooling capacity its important to maintain the cooling in a good condition28wire drawing basics page28/29vermeulen dirk 01/05confidentialcomments on cooling installed electrical motor power has to be in accordance to co

27、oling capacity of the capstan : a 61kw motor on a 620mm capstan makes no sense. motor will be used in the worst conditions = more losses. cooling capacity can be increased by extra air cooling up to 15% measuring the wire temperature on the capstans with an ir meter is a fast and cheap control, whic

28、h should be done on a regular base and always in case of drawing problems.29wire drawing basics page29/29vermeulen dirk 01/05confidential2. master the deformation temperaturereductions : 30% for loca15 to 25% for hicatapered reductions = equal power per pass correct die angles , - 25% reduction with

29、 6 - or 10% reduction with 20 gives excessive (waste) power (= heat)30wire drawing basics page30/29vermeulen dirk 01/05confidentialexample 2.00mm from 6.5mm rod loca 0.10%c 15m/sec31wire drawing basics page31/29vermeulen dirk 01/05confidential3. heat by frictionthe wire is touching the die surfacehe

30、nce friction=heatto reduce this friction : a lubricant is usedpurpose is to separate the two surfacesdiewirelubricant32wire drawing basics page32/29vermeulen dirk 01/05confidentialmaster the friction = lubrication1. for wire drawing min 1 g/kg lubricant film is needed to have a good separation, lubr

31、ication : this for widia diese.g. 4.75mm needs min 9.3 g/m1.00mm needs min 2 g/mfor diamond dies 0.5 g/kg is sufficient2. this lubricant film has to be composed 3. its also necessary to have a good adhesion to the wire surface33wire drawing basics page33/29vermeulen dirk 01/05confidentialcomposition

32、 of the lubricant film hard components1. can be the coating : lime, borax, zn-phosphate (= a good adherence)2. can be present in the drawing soapcalled : fillers lubrication components1. have to come 100% from the drawing soap2. this is called the fatty acids34wire drawing basics page34/29vermeulen

33、dirk 01/05confidentialsoapsna-soaps: often colored - rounded forms less dustca-soaps: rarely colored coarse forms dusty in handling35wire drawing basics page35/29vermeulen dirk 01/05confidentialproperties of drawing soapsna soapca soaplubricant film thicknesslowhighpressure support= separation (die

34、to wire )lowhighfiller contentslow 50%for? speedhigh 1000 m/minlow 60% in combination with coating orafter some passes ca soap! cooling is important : if soap burns nothing remainswater soluble ( preferred for degreasing )ca soap- low % fa, high% fillers= no coating necessarybut low amount of fa wil

35、l result in higher wearand rupturesif cooling fails : still the fillers are presentdrawing is still possible but high wear- also advised for galvanised wiresnot degreasable 37wire drawing basics page37/29vermeulen dirk 01/05confidentialgraphs not oksoap amount : descaled0.000.200.400.600.801.001.201

36、.401.6012468101215holeg/kgdry materialfatty acids38wire drawing basics page38/29vermeulen dirk 01/05confidentialgraph not okbaz 3 - residuals g/kg (6.5 - 3.23 mm)0.560.630.730.710.710.690.740.130.240.240.260.270.290.000.200.400.600.801.001.201.401.601.802.00wd12345ompassg/kgzeep vicafil tn 1373 tcoa

37、ting traxit zel560 min.target coating + soaptarget coating 39wire drawing basics page39/29vermeulen dirk 01/05confidentialgraph oksoap amount : descaled0.000.200.400.600.801.001.201.401.601.8012468101215holeg/kgdry materialfatty acidsdiamond die40wire drawing basics page40/29vermeulen dirk 01/05conf

38、identialwhere to use what soapna soap- high %fa , low% fillers= in combination with coating orafter some passes ca soap! cooling is important : if soap burns nothing remainswater soluble ( preferred for degreasing )ca soap- low % fa, high% fillers= no coating necessarybut low amount of fa will resul

39、t in higher wearand rupturesif cooling fails : still the fillers are presentdrawing is still possible but high wear- also advised for galvanised wiresnot degreasable 41wire drawing basics page41/29vermeulen dirk 01/05confidentialmaintaining a good lubrication film1. start from the first pass with 1g/kg2. master the cooling of the wire3. avoid mechanical contacts which damage the lubricant film4. use the right soaps5. keep the dies in a good conditionworn dies destroy the lubricant film + create def