Modern Steel Products (2014) - Wire & Rod Mills: lecture 23

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Modern Steel Products (2014) - Wire & Rod Mills: lecture 23
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23 (2014)
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Professor de Cooman takes the topic of rod and bar manufacture, including non-destructive testing. Both the production and metallurgy of the alloys is described. This is a part of a course of lectures given at the Graduate Institute of Ferrous Technology, POSTECH, Republic of Korea.
Keywords The Graduate Institute of Ferrous Technology (GIFT)
Steel Mechanical fan Scouting Connecting rod Bill of materials Blast furnace Wire Winterreifen Cartridge (firearms) Spare part Single-cylinder engine Surface mining Tool Molding (process) Mail (armour) Blast furnace Typesetting Semi-finished casting products Connecting rod Automobile Eisengießerei Railroad car Clothing sizes Wire Scouting Cartridge (firearms)
Blast furnace Semi-finished casting products Connecting rod Scouting Finishing (textiles) Connecting rod Wire Page layout Printing Blast furnace Wire Cartridge (firearms) Spare part Spaceport Ship of the line Stream bed Ship of the line Mail (armour)
Tin can Connecting rod Scouting Wire Sizing Cartridge (firearms) Train Gentleman Rolling (metalworking) Continuous casting Ship of the line Stream bed Bass (sound) Firearm Stock (firearms)
Semi-finished casting products Connecting rod Kickstand Scouting Wire Blast furnace Groove (joinery) Scouting Sizing Rolling (metalworking) Cartridge (firearms) Rolling (metalworking) Cartridge (firearms) Caliber Ship of the line Material Cylinder block
Steel Kickstand Scouting Machine Connecting rod Page layout Blast furnace Wire Rolling (metalworking) Spare part Rad (unit) Surface mining Ship of the line Mail (armour) Material Cylinder block Typesetting Blast furnace Connecting rod Automobile Machine Wire Ammunition Fahrgeschwindigkeit Cartridge (firearms) Cylinder block
Hot working Kickstand Scouting Cylinder head Blast furnace Wire Game Volumetric flow rate Spare part Rad (unit) Surface mining Tool Mail (armour) Material Typesetting Cylinder head Semi-finished casting products Connecting rod Stagecoach Finishing (textiles) Commode Wire Scouting Sizing Cartridge (firearms) Fahrgeschwindigkeit Tram Spring (device) Wärmebehandlung Stream bed Cylinder block
Typesetting Fiat 500 (2007) Airbus A300 Connecting rod Cord (unit) Towing Wire Printing Wire Surfboard Gear Winterreifen Alcohol proof Cartridge (firearms) Piston ring Ship of the line Material Jeep
Connecting rod Mechanical fan Committee Coating Scouting Cord (unit) Machine Cylinder head Wire Wire Winterreifen Gear Conveyor belt Conveyor belt Screw Book cover Piston ring Piston ring Stream bed Ejection seat Water vapor Material
Typesetting Stagecoach Berlin (carriage) Semi-finished casting products Connecting rod Book cover Mechanical fan Scouting Machine Machine Cylinder head Wire Blast furnace Wire Turning Belt (mechanical) Tire balance Cartridge (firearms) Conveyor belt Spare part Book cover Insulator (electricity) Piston ring Stream bed
Stagecoach Machine Piston Finishing (textiles) Cut (gems) Cylinder head Blast furnace Belt (mechanical) Gear Cartridge (firearms) Tool Material Mail (armour) Cylinder head European Train Control System Connecting rod Tool Mechanical fan Machining Radial engine Machine Turning Tire balance Spring (device) Steering Axle
Mockup Scouting Mixing (process engineering) Turning Spring (device) Striking clock Truck Connecting rod Lagerstahl Steering Finishing (textiles) Railroad car Clothing sizes Casting defect Wire Gear Cartridge (firearms) Nuclear fission Spring (device) Flatcar Kurbelwelle Semi-finished casting products Lader <Verdichter> Steel Hot working Vehicle Transmission (mechanics) Cylinder head Wire Angle of attack Outline of industrial organization Gear Mechanical watch Spare part Tagesschacht Free machining steel Material Kurbelwelle Typesetting Widerstandsschweißen Tool Cut (gems) Stagecoach Cylinder (geometry) Machine Gas compressor Scouting Angle of attack Speise <Technik> Surface mining Tagesschacht Last
Widerstandsschweißen Game Steel Lagerstahl Spring (device) Steering Cylinder head Casting defect
railroad car cars I have looking at so let us have a quick fewer fans the wire a mail part that In an integrated but still applied you you will of course use steel From high-purity steel coming from blast furnace and but the basic oxygen view as a furnace and a new go continuous casting their depends what you out which a continuous caster can do if it's it makes but molds usually need to turn these into billets yes the square round billets Dance and violence of blooming mill and billet milk or were you make if you have multi stranded but if you can make it if you tested the kingmaker mulch strand circular all square billets valued view of course still need to do the blooming Nelson you go straight that to me the reheating furnace just now depending on the product because there will be more or less take care taken of the surface after of these ballots were so if the application is requires set them you will for instance to ultrasound testing of your bill you you'll be looking for the facts In did structure that that are not visible slightly but below the surface and you can also do billet conditioning that means you are basically removed the oxides surface defects and d car ization layers on top of your ability so you have to be a perfectly conditioned to that but the filets and going to the reheating furnace at end similarly to what would we see 4th for strip Meltzner watches it its looks different of course you do roughing mail yes and then an intermediate Millinor finishing meant I and in the case of wire we have the special cooling table which will be discussing in a moment where you do but the transformation that would be the equivalent of runout table and a cooling In the renowned table for hot strip cancel let's have a look at what about that production levels we have here as well typical 80 of the reheating furnace will have capacities of around 100 tons maybe 200 calls for how long the amount of steel that is being processed the yearly production of it normal wire and abduction is usually from 350 to 500 Toms but thousand tons per year without a little less than half a million tons a year the billets that we used like to start are but of 12 to 18 centimeter In in section rolling speeds depends of course uh 0 but on the type of fraud you make if you make a very small wire has to be rolling speed at the exit will be very high 100 meters per 2nd but if you make bar knows or barring coil is bodice this section of which is small enough so you can still Correla but 20 meters Pesek and will the gold products that are made are way around barring coil and bar bobbing it's too thick and the application doesn't allow you to abandon them and this is a typical Section matters so the wire typically wire rod would be 5 mm to 20 millimetres the Bahrain coil 14 to 16 millimeter about 6 centimeters yes and the round biases that you don't bend all depends on the application again if that section can be smaller than the Boren call of course it's just what the application demands where you can call it on a difficult volume of it the bar and wire and borrow production unit it's that you you don't make 1 single type of product in general and users kind of spread out over about 50 % goes into wire rod and and bars are either In coral or not think oil and and their it's about half and half half will be corralled have be just straight bars what's also important here is that but these production units do not necessarily make only carbon steel as they can also be involved in producing other types of steals our so typically the majority of the product will be be carbon steels but I you made up the find Wiren bars steel production units which which produces also the same product the same type of product but stainless steel using stainless steel so you you are there is more variation in the in the type of compositions that
you can so that the debate in the basic layout is as I said the reheating furnace used a picture of reheating furnace stands up indeed the ability come in at 1 side come come out through this much smaller of course exit port yes and the reheated billets come out and then they go through a roughing them and roughing mail general moment and that the roughing the the process of the rolling wire ends the bar products goes through special Mills as with alternating the vertical and horizontal stance stems rough mill intermediate milk and then the finishing and you have lines at will do the deed the transformation into a media and the good cooling off the past 1 of them straight bar In a cooling bed but if you have bars in coils of wire you will we have the the wire rods are usually he treated as they come out of the year the finisher and the bars in Coral can be treated for the transformed after them so this is here at the the finisher yeah and so you can see the section of the the the product decreasing as you go through the the unit
this is a F In In intermediates part of the wire and Bob male and you can see here that you see the roles are in this case of vertical the horrors of Excuse me horizontal in this case they are vertical and then hear there again horizontal and vertical can etc and so the end the the
reason is if you work and you cannot make the if you have 2 roles yes you cannot make the other than any of the stock with a big section is you cannot make the the final section of US by a doing a circular attention beyond the yen this section in a circular of matter and energy the reason as is is because you you rolling basically rights if you if you rolling things out they will tend to Due to assume district and so the way it works you you basically have oval shapes yes as you as you do do the reduction of the year this section there are many
steps many more steps in the defamation this is the case with which would be a more on the old-fashioned their case where you have a blooming mill remember that's that's where you have a heavy have euro sections such as in or you have a Bloomberg said so in a nowadays because of the the continuous casting lots of this blooming is they're not necessary anymore you can just basically cast directly the bar yes portability in the right size this that reduces the amount of the number of of stance that you need to have USA but here you can see that in the evolution can be quite dramatic this is Sorensen example you word goes all falls square oval as it depends very much on the technology that's installed this is an
example here where you go from oval round oval round here but the basic point being that you don't go from starting a situation which may be as a square ability to at the end situation by a continuous diameter reduction will you go through these rectangular sections look it's a it's not the case and went of course you you toward the end of the process where your your product usually has to have a very perfect round all square with the will of only talking here about round but if you need square square-shaped and think so there and and this would have descended in the finishing mill yes you have 506 Tanzanian more where you are where you generate the final shape the final required checks and in this case your your stance will maker In this case the circular sections and you can have too high there around passes like this 1 or both of the 3 roll round passes like this 1 here that we've got an and
here these in the finishing mill when you have this week role reducing and and sizing blocks that we call them we don't really call them stance the yeah you have the yeah the roles oriented in wide positions and and Tai Wai positions so as to have C When you work when you roll every time you roll like this you will always have a little bit of the material that will be squeezed out and then so and that is why these you his way turn you go from the vertical to horizontal situation of from of otherwise situation to untie why situation because in the next In the next and we'll be doing it the rolling in this way it role in this way and so here of course will have it I'm still a little bit of the material that you you don't need this material this release gets squeezed out it's just because it's an opening it doesn't get to reduce against some people think this material gets candidates were pushed out from between the role that's not really would have just you don't drop sites not reducing them and so so exodus squeezing out is reduced a lot and also the it's even better with these 3 role reducing in size and blocks it and this is an example of how things look it again this is
a typical example here it's it as a slightly older set up there in and you can see that there want to really this 1 to the 4 5 about 5 of these blocks guests of the company that makes those is is very famous just because it has been basically owns the technology for these three-year-old reducing and sizing blocks and it's called Cox from the Germany in its and so that's very often the type of equipment that you find at the end of the bar FOR YOU
milk but again here we won't go into this but obviously you all of you understand that we have a a section of material that has this kind of section and you have to turn into maybe something that's just a few millimeters a in diameter so things become very very long there's been a bar a mail very long and so on and you go from there 1 stand to another stand another step so there'll be it and you remember what we talked about the hot strip mill you always have problems the new unit no problems but you have to deal with the fact that you may have pensions has between the both and you need to have of course constant mass throughput yes if in 1 1 male produces more has a high velocity exit velocity than the next mail has a entry velocity you're going to accumulate material in your mouth and you end up with with cobbles destined can be pretty horrible when this happens because you know you get this very high temperature spaghetti and all over the place and and once it's cooled and you have to know removal and cut it up it's it's a terrible loss of time so the smells and all of Austrian example of this in a moment in if you take this into consideration for the the processing so Of course when you make this section is much larger than it this is a larger section and you don't need as many stands in in fact you may just have a few were roughing Stetsons performances that if you make round bar mill will have a heating furnace you have you can have a blooming mill perhaps this but but you will have done it going to roughing mail and intermediate middle and finishing mill can be 1 male position yet with different Stenson and where due the bar goes back and forth until it's got the right section the close of the Piccoli machine structural parts that use the based on these bars will be produced as well in wire a mail Of course but we never much smaller reductions larger reductions usually so you go From heating furnace there may or may not be this reversing rougher that's similar to this 1 that depends on what we start with the and then you go through but the intermediate mill and its wire rod blocks where all the stands are intended 10 he does so again I want to the
mentioned the fact that all these males the material comes in tho 1 stand Goosen another step and so How do you manage the the material flow the mass flow through the luck of the line against but nowadays what is being done this is tension free role as you basically have something that needs to reminiscent of the Bloomberg a little part between the stance rolling stands of a finishing mill has so and in this case date the loop that you have is such that you eliminate the tension so there is no tension between the the In the the White yes between the steps so this way we are able To provide exit but constant exit velocity think this constant this comes exit the lost his constant and that is rather important because the heat the In the Heat Treatment of the cooling that's being done after the finishing this is the heat treatment requires a constant exit speed will for the cooling battle for the with including that is what they received did the name we use for the run out equivalent of the runout table and hot and then the sex it's fees must be synchronized with 1 of part that you and see that animal would looks like the part that puts down the owner of the wire on the cooling back and that's leading head laying head and that's is rather slow equipment well it's not really able to respond to exits the velocity changes and that's critical To keep the at the exit velocity constant 10 it was a a mail can make a very large not only and a wide selection of diameters but a very large number of diameters yes so for instance this is an example here all of the situation where the wire Milton made sections going from about 19 mm to 75 mm look at and so you can see the Rangers the actual ranges of the actual diameter so that it can make but the way it makes it is by combining different stance as and in the stands having the different types of rocks yes so there is a very large number of roles that you need to manage in these wire and bar males has you don't it's not like a hot strip mill where you always have the same work crawl and a backup role for circumstance here it depends on what you're going to produce I that's a for
instance you can see that in this smell this particular million have all full and round the changes hands and so on if you if you I want to make said the exits rougher diameter is 100 and 15 mm about 10 centimeters and you want to make it's 35 millimeter wire other fares will this is the sequence that will have to be mounted so that so that means that you have to set up the middle for specific products yes now you realize of course that when you making a while there is only 1 wire the goes would lush right Sewell if you make small wire that's a productivity is low so for products now it is very often that's what you have to live with because you need to make products which certain specifications in terms of the dimensions you know if if they ask you to make the 5 more once the centimeter diameter of you shouldn't be 1 . 3 or 4 of sometimes wonder it's got to be that dimension has so there's not much you can do but there are products which are commodity products yes where did demands are last as and where you can watch and of course the costs it added the prices are much less their it's important to increase productivity and so there are possibilities to do this for instance if you want if you have read bar for instance commodity product yes you can you there are units that will allow you to make free markets or more more more bars in Paris this an example here where you have about 2 a centimeter large Reebok tennis and it's produced here in this unit that's the that splits its is Boris splitting unit and when you enter with something that looks like best against and after this unit it's you know it's splits in these that got and so the the amount of material you produced amount of bars you produce per unit of time is increased that that allows you but of course you can only use it for LaRouche production values smaller rebars sizes and obviously D we we're talking about a commodity products here the temperature control as always very important which would steal certainly looked carbon steels yes so typically In a typical a mail the temperature profile will be reheating at 1100 for 20 minutes of that remember there that slabs into hot strip mill foreign 2 hours at 12 58 has this is much shorter 1 of the reasons is of course that these billets are much smaller than this huge slabs yes no OK and the temperature decreases slowly as you go through the lion s you end up it would relatively simple rules when it come and will discuss those when it comes to how you cool the wire after it's been produced "quotation mark so and so will seize a first-ever cooling too From the defamation temperature to about 10 has and then you do what you would call Stillmore more cooling has 2 typically 5 7 2 and we'll see that at that temperature is the temperature that we would like to carry out the polite transformation and then you you air cooled the began as always in a In the steel hot the production area when the temperature is not homogeneous at the surface and the interior of the material so if you look at the surface you get the blue profile here you have the roughing mail the intermediate mail yes and every time you go through the mail you get cooling from the from the middle of the surfaces it's cool that at this very center of the material it's a very different story every time you you pass through the defamation stages you get heating the material heats up in the center so that you want when you get out of the do the males the surface temperature increases again as an and and this is the actual say average temperature so in at year-end and when you want to come 2 d I to having to do the transformation has there will so that you will have to apply cooling and these are these schooling stages as did the used at the exit of the on on the the wire after
GE exit from the mayor OK so what why do we need to do this well 1st of all the the widest deals that we make a very often steals that contain where will work perlite is a very important constituent and so let's just let us make sure that we will will go into details in the product but 1 of the the the products that are being made with wire are with cold cold heading steals gold had quality steel the CHP and that's that or or steal for fast and bolts are faster nails are fasteners yes so I typically have . 3 2 . 5 carbon in the steel yes so when you cool this steals .period 4 years you call this deal 2 of quite to know you get of course it's a discontinuous cooling so you get this is pulling currently as new CCT diagram and and you see that the transformation if you do slow cooling transformation starts at 7 PM There is a transformation that starts at 7 under desk and if I use a high cooling rate of 15 the transformation is starting around 600 degrees C know so temperatures that are much lower then what the phase diagram tells you something and if you look at that the temperature in no in the why are you as you see that when the transformation starts here these red lines and then then this would be for this temperature and you see that the temperature of the transformation started the temperature increases and that this is this phenomenon is called regret colossus and it's basically the heat of transformation that's released and that gives you a a slight increase temperature and then what happens in terms of the a transformation news will 1st you can see here of course as soon as we passed the A R & B E 3 temperature as there is you can form some varieties of this what happens you forms an initial amount of far-right hints but the bulk of the transformation going from here to here is the perlite transformation some 80 per cent Of the MicroStrategy will be more than 80 per cent in this particular case will be the police with indeed the fastest the cooling and to lower transformation temperatures are very important for wire products because that this is just the best my perspective for strength yes so there are different ways to do can do this let's let's Francis you you do the cooling those which forced air which would be about 10 degrees for 2nd or you can do the cooling in a and of metal bats it for instance let let bad lad is doesn't react with steel and you can you can use it as a cooling Mejia was but it also has very low because of lower In melting temperature has so you can basically heated up and the advantage it doesn't evaporate are a dozen alloys with to steel and that and it's a very good he conducted so you can cool the your steel to the temperature of your bad very nicely so this is what you get if you will use steel and lad 20 degrees per 2nd forced air and you can look at the the the strength that you get from the same material as when you Due b the the the transformation has in this land or indeed forced air-cooled so the mean temperature for transformation the mean temperature transformation in forest areas around 640 in the lad yes it's around 600 or more this very often this this treatment and led called patent this is been using a I had as the low-temperature cooling media we witnessed site the cooling rates and you see that that we can achieve an impressive increase in In strength despite doing the transformation that higher rates and lower temperatures that is 1 method that is used by the steelmaker To increase strength that is transformation at lower temperatures and higher calling rates when this the products are made yes we can also increased the strength even further by reducing continuing to reduce the Inter Lamela spacing of the perlite has and that stung by formation so if if you take it's 1 of these materials the school back
Francis C. of forced air cooling led patenting gives me about tensile strength around 2000 about 2 2
thousand so that would be somewhere here if I draw on this material yes thank you I get an increase in In strength In string of course and I get the reduction a refinement of the the perlite and and you can see here the the urge the increase in strength in almost 3 times in starting from a thousand units close to 3 data Pascal and there is also important to have a very small Starting Mike rastructure To do this that could so
how does this how'd you do that idea actually carry this out the this strong transforming the all this wire that comes out at you don't have to 100 meters the 2nd idea how you do the transformation would you managed as well is a clever way in which it's being done and With 8 with this this piece of equipment here against the the wire comes in as a wire yes and this machine turns it into His Pyro yes spiral shape why instead of having straight wire it now comes out as a spiral that students concede committee is becoming it coming out of the sport is to machine this laying ahead as spiral and then you put it down on a Clinton has and you can see it is a this is the wire laid down on a coolant so this is the list of the top few Of the this cooling table than you see here the the rings the wire and it's carried by a conveyor of change and the to take such along Over the cooling section the cooling section itself view from the side so you can see here you have the these rings yes there put on top of each other and the load and so it's open hands it's open this conveyor belt is open and you have friends the blow air through it Lincoln and so that will give you a cooling you can control the cooling by having a cover yes but put cover on top of the the ratings so that the cooling rate is his last right so we can adjust the cooling rates on this this and that picture here this is
delaying had he said the ring wires as they are to go on the air the wire rings as they are on the conveyor belts and you see this the covers but the covers here that you can put down over this over Europe cooling section to decrease the cooling right now
and so as as the that the wire cools down yes Of course it's it's it's not write anymore red-hot anymore and at the end we can form these coils and my putting them over this go here just for fun and for final cooling and then you can make these these corals of the wire so this is for about how you produce why it is so that in the the case of bar the demanded the formation of of production is is much smaller units this and other and that's the way this little bit shift in emphasis when you make barred from the bar for instance bright bar such as the 1 you see here so you then you start with heating the billets you for general use when rolled up yes so that the data have the rights general dimensions they're usually then kneeled and pretty aligned and then we have bar appealing again this is not for all kinds of bars not for rebars for bright bars that used in a machine parts yes Oral motorists there no In the bar appealing you remove oxides the scandal and generally this chills scanners because the other side may have cooled down faster and be of for instance said take so you want to remove it Wilson may want to remove surface cracks so that you can achieve dimensional accuracy and high surface finish at the bars are very many application there have to be very straight with so you have to straighten them out and then there in many applications you also want to the ends of the quality of the ends
of the bar has to be assured him to have certain finishes so you would talk about sham Frank and and facing also a few example for bars well are typically what fully tested ultrasonic linked to to detect cracks and imperfections inside the material marked and if it's required by the application there may even be the final grinding some of the bodies to get high quality services so there
you have imagined that these these bodies that come out of the a mail yes they will pass through the 1st pass through a unit that does the peeling yes and I don't have a really good picture of the process but basically these bar entered the peeling machine and there is a turning heads in them and peeling machine with carbide tools yes that will remove the terms of things around and it removes at very high speed it removes all these are the the surface layer basically the moves oxide etc and it gives a very high again the dimensional quality
and some of the bars require will require drawing so much lengthening so you can lengthen the the bar and get a reduction in section this way you can have strange that drawing it can happen by spinning or if the Oracle you can basically trawl and the Rawls yes when you do this drawing so you basically have the circle tool with cylindrical tool would hole in as you pass your wire or your body through at us and when you do this it's very it's of critical importance that but in the forests with which you pull and In particular the angle here the angle of the tool it is chosen very carefully why instead because if you don't do this you get what called Chevron defects in the bar is a Chevron defects in which you can basically CDs are cracks internal pressure to the bar looks perfect from the outside but internally you have the Chevron defects and the Chevron defects occurred for the following reasons In box because when we are reducing bars the the diameter of the bars you have plastic deformation inside the and if the plastic deformations zone does not reach to the Center Of the bar so if there is a part of the bar dead does not before we call this the dead zone yes in the dead zone there is no defamation and well then it this part of the forums and his party from and and the dead zone will crack basically obviously because it it doesn't become longer and should cross the crack and this depends very much on the list bungalow here of the drawing and the amount of deformation that we get this and so on so if the if the other is very small of course we have safe situation has 50 although is very the very large and very steep alike in this case and we get shaving that's also not very good and so would you would you need to have and you also want to avoid this intermediate stage where you have a dead zone a dead zone mentioned where you when you start making Chevron marks straightening and finishing of the ends Of the bars is very important to so this is not so you have a chance for a machines which will change the dependence of the the bar for instance in this case it's it's it's 2 or yes and Andy and fission finishing here this year and that has to be of course flat and of high quality straightening happens is done and special straightening machines since this this wooded looks like you have the bath straightening machines few have round bars used typically have had a pair of roles but shaped yes consider not flout the mineral shaped like this and this 1 2 this and their crossed so when when the bar passes through it it turns it does 2 things it turns and it's and it's being slightly bent when it goes through this rule is not to keep it in place if I look From the front the guidance some of the bars is is basically getting little that amounts of deformations back-and-forth so that it becomes strike and there similar types of equipment for the fury if you bar is square bar there's an all-around our you have a profile straighteners look at very important for bars and prevails is that there you need to test I need to test them to check the internal quality with just seeing that and you have the Chevron marks whichever remarks absolutely not visible from outside from the other side so you need to I do surface quality of your materials you have to make sure there are no cracks for instance at the surface and you do this with eddy current testing that's the most a common method His eddy current testing you can also do it to win automatic visual inspection otherwise you have to do it and it has to be an inspector who will actually inspect all the 2 states order bars it's usually amended production rates are too high for 1 person to do this so what you can still but you can do this with a computer who will recognize that you will take images of the of the product as it comes out and and analyze data the images and make reports about the defects it's detected cancer the other method is the eddy current testing this was electrical nature and both of these methods because they you can ultimatum over a popular lately bonds and then when it comes to the internal inspection you cannot use eddy currents testing because any current testing is only sensitive to surface defense and of course a visual inspection whether it's in a person or a camera with a camera that it's the same thing you can only see the exterior so well with ultrasonic testing yes you can do internal inspection visits and nowadays I you have differences these new probes face of rape probes you can basically test 100 per cent of your production and make sure that there are no internal defects in particular that there are no things like Chevron marks I'm right so Boren Rawls into past times and strain rates are can be very high deformation rates I don't going to talk about this too much with wire and bar all there is absolutely no reason why you cannot use alternatives form on new work the processing methods that might hurt when you do the deformation at high temperatures and yes you can do standard trolling normalizing rolling or thermal mechanical rolling over of the steals yes and again
but the use of concepts like the ones we use for thermal mechanical processing of strict you can apply these concepts to wire and bar products but can still with discusses at length and there's no difference in the approach let's have a look now at some of the products that specific problem so In when we come to wire products wire products these are the 5 groups of the applications which are the most important 1 higher courts steel Gold having quality steel spring steel bearing steel and free cutting and what is important in each application is Strange yes I certainly in the 2 top ones but in an application like spring stilted it's fatigue is extremely important us and in case of burying steals and spring steals cleanliness is extremely important and you don't want to have a material failure due to non-metallic inclusions and the last application free cutting still that's where you make small steel parts as you have the requirement of machine ability is important but we just 2 to wrap up this the report it's a few things about Boris Yeltsin bars we talking about have year sections has so these are typical applications you have shafts this is a a typical example here a forged crankshafts and you have gears yes the there is this dear for a trip from just part of transmission parts of this 1 you have Hannum will still say that used to be treated conditions for instance this bar and there is an application of stabilizing buyers are used for the steering of all vehicles trucks and would the cars and so there usually isn't usually bars at our hot forming quenched and then we also have heavy springs so applications such as these very heavy said springs such as railroad car yes look at so we will talk about these in more detail when we meet
next Tuesday we will do it


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