What Causes 1.2738 Steel Cracking | Mold Failure Guide

1.2738 steel cracks mostly because quenching stress too big or pre-heating not enough, suggest before quenching pre-heat to 200–300℃, cooling rate controlled at ≤50℃/h;

Contains Ni about 1%, toughness although high but welding repair not proper still easy to crack.

Repair time uses low-hydrogen welding materials, current 80–110A, multi-layer welding and at 550℃ tempers 2 hours eliminate stress.

Material Defects

Non-metallic Inclusions

1600 degrees' steelmaking furnace inside, steel water boils rolls. Workers in order to get rid of steel water inside's oxygen, towards inside throw aluminum blocks. Aluminum and oxygen bump at together, became hard bang bang's aluminum oxide particles. Cools into a few tons heavy's steel ingot time, these hard particles, still have manganese sulfide etc. dregs, just forever stayed at steel block stomach inside.

Normal master takes milling machine cuts drop 10 millimeters thick's steel skin, at root feels not arrive abnormal. Until polishing working sequence, fitter holding 800 grit's oil stone a little little polishes mold cavity. Wool felt turntable with per minute 3000 revolutions's speed high speed rubs surface, originally bright's steel surface on, starts to float out one stripe stripe 2 to 5 millimeters long's fine small trailing print marks.

Steel material itself's hardness approximately is 30HRC, and those aluminate impurities' hardness can reach 70HRC. Polishing tools bump into these extremely hard's particles, only can take surrounding partial soft's iron chips grind drop, surface just left down deep about 10 micrometers' small pits.

· Sesame big small's concave pits

· Following polishing direction's fine long groove lines

· Originally mirror surface's place suddenly emits dark

Quality inspector takes roughness meter one measures, originally requires 0.05 micrometers' Ra value, directly soars rises to 0.8 micrometers. Worker only can helplessly takes out 1000 grit rough sandpaper, anew takes this layer skin grinds drop, white white consumes 12 hours's human labor.

Problem if not solved, after disasters endless. Heavy reaches 10 tons's mold by hoisted onto large type injection molding machine. Machine one opens, melted's PC/ABS plastic with per square centimeter 1500 bars' high pressure, ruthlessly crashes enters mold cavity. Steel material still wants to bear from 200 degrees to 40 degrees' violent cold hot alternates, every 45 seconds cycles one time.

Size exceeds 50 micrometers' impurity particles, completely is a dead pimple, not has any elasticity. Every time 1000 tons's lock mold force smashes comes down, surrounding's steel material will happen million parts of a few millimeters' micro small deformation. But these hard particles thread silk not move, hard vividly takes surrounding's metal pulls tears open.

These two kinds substances receive heat expands's amplitude differs three times. A few ten thousand times cold hot impacts after, micro small's cracks just at aluminum oxide particles' sharp corner place pops out came. Cracks follow impurity distributed's direction, every day with 0.1 millimeters' speed, quiet no sound breath ground towards steel block deep place pierces enters goes.

· Plastic rushes enters comes' enter glue mouth beside

· Turning corner place's R corner (round corner) zone

· Very deep's bone position (rib position) most bottom down

· Distance cooling water pipe not reaches 15 millimeters' place

They take steel water inside's contain oxygen amount dead dead press at 15ppm (million parts of fifteen) inside, contain sulfur amount drops to 0.005% below. From furnace bottom towards up blow argon gas, rely bubbles take those light float float's waste dregs bring to surface, all skim goes out.

Steel material ships to mold factory, laboratory first cuts one piece 20x20 millimeters' small block, stuffs to microscope below enlarge looks. According to industry inside's ASTM E45 standard, A class sulfides cannot exceed 1.5 level, B class aluminum oxide must stick at 1.0 level inside. As long as exceeds standard, whole vehicle steel boards directly pull back steel factory.

Flaw detection worker holds 4 Megahertz's probe, at coated full sticky liquid's steel board on slowly slides. Screen on suddenly jumps out a exceeds base line 20%'s abnormal wave. Instrument displays, at distance steel board surface 150 millimeters deep's place has one lump impurity, and that position just good is mold receives pressure most big's place.

Boss in order to every kilogram saves down 2.5 yuan, bought not passed degassing handled's cheap material. One set made one and a half months, purely machine processing fee just smashed enters 300 thousand's car bumper mold, on machine trial hit not reaches 8000 times, enter glue mouth there “pa”'s one sound thoroughly broke.

Repair mold master holds argon arc welding thinks takes crack pairs on. 2000 degrees' welding wire just just melts open, high temperature just takes surrounding hiding's impurities burns explodes. Waits repairs welds' place cools thoroughly, sprays on flaw detection red liquid medicine one looks, deep reaches 3 millimeters' fine small cracks like spider web same climbs full whole surface.

· Buy steel material must bring VD/ESR refining prove certificate

· Milling machine processing before first do one time ultra-sonic wave scanning

· Not do temperature exceeds 400 degrees' surface processing

Micro hardness tester one presses, impurities much's place, anti pulling tearing's ability compared normal steel material low drops 40%. Just because stomach inside hides dozens micrometers' residual dregs, heavy reaches quite a few tons, value seventy ten thousands' 1.2738 mold, only can by treated as scrap iron thrown at workshop corner.

Segregation & Banding

Steelmaking factory pours out heavy reaches 20 tons' boiling hot steel water, pours enters casting mold inside. Cooling is a extremely slow's process, thickness 800 millimeters' 1.2738 steel ingot center completely solidifies needs whole whole 72 hours. At this long long's dropping temperature period, steel water inside 0.4%'s carbon and 1.5%'s chromium elements at liquid state area inside swim walk, slowly gather into one lump lump high concentration's alloy area.

Heavy type forging machine uses 3000 tons' pressure takes this piece big steel ingot presses flat pulls long. Originally gathered at together's high concentration carbon and alloy elements, by external force hard vividly pulled into one stripe stripe parallel's noodle shape.

Rich contains carbon elements' deep color strip band, hardness will abnormally soars rises to 42HRC above. Beside lacks carbon's shallow color area, hardness falls drops to 26HRC. Whole piece steel material at micro level becomes a soft hard alternate's thousand layer pancake.

CNC milling machine's cutter plate with per minute 800 revolutions' speed cuts grinds steel block surface. Cutting grinding sound originally should be even smooth's rubbing sound. Cutter blade bumps into hardness 42HRC's high carbon band shape area, machine tool main shaft immediately emits out piercing ears' abnormal sound, main shaft load table instantly jumps from 40% to 85%.

Originally can continuously cut grind 5 hours' tungsten steel coated cutter blade, supported 40 minutes just collapses mouth reports scrap. Operator only can forcibly lower drop feed speed, takes per minute 1500 millimeters' walk knife amount drops to 600 millimeters. Hand goods period towards back delays three days, cutter tool consumes costs flips one fold.

Polishing workshop's master uses 3000 grit's pure diamond grinding paste polishes mold cavity, soft hard not even's material quality lets surface presents out water wave lines same's concave convex feeling. Uses finger belly sticks surface light light slides moves, can feel out every separates 3 to 5 millimeters just appears' one pass fine tiny ridge line.

Buy steel material only looks surface test data will eat big loss. Normal business clerk holds portable Leeb hardness pen at surface knocks beats three downs, hits out 30HRC's average numerical value delivers difference. Wire cutting machine tool takes steel block from middle splits open, following cross section every separates 10 millimeters hits a point, every areas' numerical values presents out cliff breaking style's wave moving.

Heavy reaches 8 tons' mold by locked enters large type injection molding machine table. 220 degrees Celsius' melted ABS plastic with 1200 bars' limit pressure rushes enters mold. High carbon band and low carbon band receives heat expands' size difference reaches 0.02 millimeters, two ones between produces extremely big's mutual pulling tearing force.

Injection cycle proceeded two ten thousands mold times, mold internal's stress accumulates exceeds material's yield strength limit. Micro cracks most first at rich carbon band's edge tears open. High carbon band itself extremely crisp, cracks follow that stripe naked eye looks not see's zebra line rapidly extends, one day inside just towards deep place expands 15 millimeters.

· Purchase contract notes clears cross section hardness scatters difference value strictly controls at 3HRC range inside

· Thickness exceeds 500 millimeters' forgings require steel factory issues ultra-sonic wave measure thickness and crystal grain degree test reports

· Forbids takes mold bears extremely big pressure's deep bone position parallel to band shape structure direction arranges

Large type special steel factory in order to eliminate component segregation, will at 1050 degrees Celsius' high temperature furnace inside takes steel ingot stifles on whole whole 48 hours. High temperature lets gathered's carbon atoms and chromium atoms anew scatters open, at whole steel block internal evenly diffuses. This pass homogenizing working sequence, every one ton steel material wants to extra consumes 500 degrees industrial uses electricity.

Small forging factory saves down this pen electricity fee and time, steel ingot just just solidifies just pulls goes forging beats hand goods. One set heavy reaches 6 tons' television back shell mold, processes deep reaches 120 millimeters' net hole cooling groove time happens deformation.

Three coordinate measuring instrument's red gem probe hits passes steel board bottom surface, flat surface degree runs deviates whole whole 0.8 millimeters, completely exceeds picture paper requires' 0.05 millimeters tolerance band.

Installs on injection molding machine passes enters 90 degrees' cooling water one adds heat, soft hard crisscross' thousand layer pancake structure receives heat expands, mold board again happens 0.3 millimeters' twist deformation. Plastic product edges grows out one circle thick reaches 0.15 millimeters' flash hair edges, size precision thoroughly loses control.

Porosity & Micro-shrinkage

1550 degrees Celsius' liquid state steel water pours casts enters sand shape mold, volume will happen approximately 4%'s physical shrinks. Outer layer's steel water contacts cold air first leads solidifies into hard shell, internal boiling hot's liquid still at continues towards center shrinks. Thickness reaches 600 millimeters' large type steel ingot, if not has obtains source source not break's steel liquid supplements, most center's position just will by thoroughly dug empty.

Heavy reaches 30 tons' giant type steel block thoroughly cools thoroughly after, stomach inside spreads full diameter from 0.1 millimeters to 2 millimeters not equal's micro small hole caves. Takes one piece problem steel board from middle saws open, cross section center area looks starts comes just like one piece spreads full holes gaps' rough sponge.

Forging pressing workshop opens moves 5000 tons level's water press machine, tries attempts takes brings has internal air holes' metal block thoroughly presses solid. Forging ratio reaches not arrives industry rules' 1 compares 4, middle's holes gaps just not ways by huge's external force presses flat welds closes. One piece long wide each two meters, thickness 450 millimeters' 1.2738 steel board just this way brings heart part's incomplete broken by sent towards down stream processing factory.

CNC gantry milling machine installs on diameter 63 millimeters' flying cutter plate, with every knife 5 millimeters' depth one layer layer towards down cuts. Cuts drop outer surface layer 200 millimeters' healthy flesh quality after, cutter blade contacts reaches steel board's heart part area. Originally silver white color's metal cutting grinding face on, impressively appears out forms pieces dense dense numb numb's black color small numb points.

Master takes high pressure air gun blows walks surface's iron chips, leans close one looks, inside's black points all are deep not sees bottom's needle eye nests.

Even if hole caves only have needle point big small's 0.05 millimeters, towards requires extremely high's car vehicle lamp mold comes speaks, also is one piece fundamentally no ways polishes out mirror surface effects' waste goods material.

Deep hole drill machine tool top supports 15 Megapascals' high pressure cutting liquid, at steel board side face hits out one stripe long reaches 1200 millimeters' cooling water way. Drill bit just good pierces passes that piece spreads full micro small air holes' loose area. Workers towards water way inside passes enters 8 kilograms pressure's test water, water drops follows needle eye same's hole gaps a little little seeps enters mold's shape forming face.

Try mold workshop inside, 120 degrees Celsius' mold temperature machine starts to cycle adds heat pure net water. Cavity surface bafflingly pops out one layer fine dense's water drops, dips water's place immediately grows out one layer brown color's iron rust. Injection hits out comes' transparent PC plastic pieces on, all are by water vapor pushes out comes' silver silk white spots, product not good rate instantly soars rises to 100%.

Not leaks water's micro small air holes, at machine table on same same is one piece piece fixed time bombs. Injection machine opens mold closes mold, cavity internal bears per square centimeter 800 kilograms' alternate change stress. Loose hole cave place 's metal bears carries thickness by seriously weakened, actual receives force cross section area compared normal steel material less drops near 15%.

Every time high pressure plastic rushes enters comes, stress just at hole cave's edges crazy tears pulls. Three months not reaches, five neighbor connected's 0.5 millimeters micro holes at internal connect into one stripe long reaches 3 millimeters' pierces passes cracks. Cracks follow receives force most big's R corner root part one road crazy soars, takes value forty ten thousands' moving mold inserts hard vividly splits into two halves.

· Purchase bill on must surely notes clear flaw detection level meets Europe SEP 1921's E/e highest standard

· Processes exceeds 300 millimeters deep's cavity before, takes ultra-sonic wave probe takes heart part dead corners sweeps one pass

· Bumps into forms pieces numb points area immediately stops cutting grinding and applies material chemical tests retreats goods

Quality inspector takes flaw detector's sensitive degree adjusts high, screen on originally should be one stripe flat smooth's straight line, bumps into loose area immediately becomes one lump messy messy's mixed waves. Bottom wave reflect signal from 100% drops to not sufficient 30%, explains sound waves at steel material internal by that one pile dense's air bubbles gives completely swallowed up.

Machining and EDM Stress

Machining Stress

One piece 1.2738 steel board by four heavy type press boards dead dead presses at horizontal processing center's work table on. Machine main shaft rotation speed soars reaches per minute 12000 revolutions. One handful diameter 63 millimeters' corn milling cutter ruthlessly crashes enters contains has 1% nickel's steel block inside, iron chips with per minute 150 meters' speed towards outside flies splashes.

Cutter blade cuts open hardness reaches 30 HRC's alloy steel. Contacts' place pressure intensity instantly pushes to 2000 Megapascals. Sharp's cutting grinding blade hard vividly tears open metal's internal structure. At microscope below looks, steel material surface towards down 0.1 millimeters depth inside's round shape crystal grains, all by huge external force pulls tears into fine long's noodle shape.

Hard alloy cutter blade surface plates one layer 3 micrometers thick's titanium aluminum nitrogen coating. Dry cutting grinding's friction area inside, cutter point temperature at 0.2 seconds inside rushes on 750 degrees. Burns red's surface layer steel material receives heat happens 0.03%'s volume expands, underneath normal temperature's cold iron dead dead pulls drags it, not lets it towards outside stretches extends.

Machine tool beside's ring shape spray nozzle sprays out 20 Pascals pressure's white color emulsion liquid. Matches ratio concentration 8%'s water dissolves nature cutting liquid one down pours thoroughly boiling hot's metal. Cold hot violently alternates at surface 0.15 millimeters' shallow layer inside, forcibly locks holds high reaches 550 Megapascals' residual pulling stress.

Pulling stress just like pulled full's bow string same, hides at touches gets up very smooth's machine processing face below. Naked eye looks not sees' fine tiny cracks lies at crystal grains' borders place, even if bumps into one little little outside world's shakes, all possible follows textures tears open whole piece steel board.

Operating worker if not has according to rules at 40 minutes time changes replaces milling cutter, blunt drops' cutter blade will brings extremely big's destructions:

· Back cutter face's grinds wears amount exceeds 0.2 millimeters

· Cutter tool and steel material's friction coefficient violently increases 1.4 times

· Exceeds 30%'s cutting grinding heat amount runs enters internal scatters not goes out

· Surface hardens's destructions depth towards down drills to 0.25 millimeters

· Processing face touches gets up's rough degree worsens exceeds 3.2 micrometers

Takes X ray diffraction instrument goes measures one down just can discovers, by blunt cutter forcibly scraped passes' 1.2738 steel board, surface crystal lattice twists deforms' degree is new cutter blade's 4.5 times. A few hundreds kilograms's strength force all smashes enters base material deep place.

Digs 100 millimeters deep cavity and makes different shape groove positions' time, breaks's danger coefficient folds times increases. Heat shrinks cutter handle pulls long to 150 millimeters, whole cutting grinding tool's rigid nature drops one big half. Cutter blade at per minute 800 millimeters' walk cutter speed below straight shivers, instrument measures out's shakes amplitude reaches 0.02 millimeters.

Metal surface leaves down follows wash clothes board same's micro small wave lines, concave towards down's wave valleys inside piles full extremely big's pulling force. Bumps into 90 degrees straight corner's position, receives force gathers' numerical values soars to normal's 3.5 times.

Machine tool walks cutter's route lines and direction, decides steel board internal tight tight degree's distributes:

· Following milling passes goes easily produces good's surface press stress

· Going against milling will leave down extremely high numerical values' destruction nature pulling stress

· Z axis one layer layer towards down flat cuts receives force distributes most even

· Turning circles walks spiral down cutter can hides opens local receives force high points

· Walks to dead corners must takes feeds enters speed hard cuts drop 50%

Fine processing stage master will special intent leaves out 0.3 millimeters' preserve life material. Changes on whole new's R5 ball head milling cutter, every time only eats 0.05 millimeters' depth, light light wipes passes mold bottom part. This pass working sequence just like peeling onion same, takes rough processing leaves down's 0.2 millimeters residual hardens layer thoroughly picks drop.

Main shaft rotation speed anew anew pulls high to per minute 18000 revolutions, every time walk cutter only cuts 0.08 millimeters. Cuts very thin runs very fast, 95%'s heat amount all by red hot's curled iron chips brings flies away.

Originally 400 Megapascals towards outside tears pulls' pulling force, passes fine processing's handle, becomes towards inside squeezes presses' -150 Megapascals press stress. Towards inside squeezes' force blocks holds cracks towards outside grows' road. Has its protection, cavity resists fatigues breaks's life span extra comes out 20%.

Some apprentices habits take 0.6 Megapascals' industrial air gun goes blows deep holes inside's iron dregs. High pressure cold air instantly blows dry pipe walls on's cutting liquid. Not has water lubricates' ball head cutter follows steel material side walls dry grinds, infrared measures temperature gun sweeps to local temperature one instant jumps to 450 degrees above.

0.05 millimeters thick's surface skin encounters second times quenching, hardness reverse normal ground jumps to 48 HRC. Extremely crisp's second times hardens layer at uses 800 grit sand paper polishes' time, like head skin chips same forms pieces towards down drops, leaves down 0.02 millimeters deep's sand eye groups.

Bumps into carbides gathers' place, machine processing's resists force violently increases. 1.2738 steel's internal has one small pinch one small pinch hugs groups' chromium and molybdenum elements. Hugs groups areas' hardness compares surrounding normal areas high outs 80 HV. Cutter tool cuts passes here time, main shaft motor's load instantly jumps moves 30%.

Micro level's crashes hits force at elements hugs groups' edges, tears open 5 micrometers long's extremely small crack mouths. Flaw detection uses' fluorescence liquid medicine seeps not enters a few micrometers big's closes joins gaps. Installs on injection machine after, 1500 tons' lock mold force every day back forth presses, long stripe cracks follows 45 degrees angle slowly climbs, pierces passes 150 millimeters thick's mold boards only wants 20 ten thousands times opens closes mold.

EDM Stress

Machine tool water tank inside pours full 200 liters special uses' spark machine oil. Purple copper electrode by servo motor slowly slowly drops down, distance 1.2738 steel board surface only left 0.02 millimeters. Machine internal's power source instantly releases out 50 amperes' pulse current, forcibly strikes pierces originally insulates' spark oil.

Narrow's gaps inside explodes open up ten thousands times naked eye looks not sees' micro type lightnings. Local plasma channels' temperature at 0.001 seconds inside soars to 10000 degrees above.

Contains has 0.4% carbon elements' base material metal becomes a pool boiling's iron water. Pulse discharges stops down's that one instant, four surroundings 20 degrees' spark oil like tsunami same jumps towards this puddle 1500 degrees' iron water. Extreme's cold hot alternates at ten thousand parts of one second inside completes extremely violent's physical quenching.

Surface forms one layer pale white's extremely hard outer shell. Workshop inside manages it calls white mouth layer, thickness normally at 15 to 50 micrometers between up down waves moves. Measures thickness instrument sweeps passes uses big current rough hits fire's areas, surface white mouth layer's thickness test values exceeds 65 micrometers.

1.2738 steel inside mixed 1.5%'s manganese elements, meets cold becomes hard's reactions extremely violent. White mouth layer's hardness hard vividly pulls high to 60 HRC even more high, far exceeds normal base material's 30 HRC.

Glass same's hard shell inside stuffs full dense dense numb numb's net shape cracks. Takes cuts slices put to laboratory's high folds electron microscope below enlarges 500 folds, can clear counts out every square millimeters inside hides dozens stripes widths 2 micrometers around's fine gaps.

X ray residual stress analyzes instrument hits out's report bills displays, tightly sticks white mouth layer towards down 0.05 millimeters' depth inside, towards outside tears pulls' pulling force numerical values pushes to 800 Megapascals.

Strong fierce's pulling force follows metal textures towards down seeps passes, at white mouth layer bottom under again scalds out one 0.2 millimeters deep's heat affects area. Bottom under's metal not by completely melts, but at 800 degrees' high temperature remains heat roasts below retreats fire, hardness drops to 25 HRC.

Outside is one layer brings cracks' crisp shell, middle clamps one layer becomes soft's retreats fire flesh, most bottom under just is normal's alloy steel. Three layers structures' hardness differences reaches 35 HRC, receives force states extremely twists twists.

Machine tool master adjusts parameters' hand methods manages controls cracks towards down drills' deep shallow:

· Peak values current from 10 amperes pulls to 30 amperes, cracks depth follows violently rises 4 times

· Discharges time drags long to 200 micro seconds, heat amount towards bottom under extra drills 0.1 millimeters

· Pulse stops pauses time shrinks shorts one half, discharges not walks' waste dregs lets second times discharges rate exceeds 15%

· Copper male surface rough degree exceeds Ra 3.2, spark pits edges must definitely appear micro views collapses corners

· Rushes oil pressure lower than 0.1 Megapascals, carbon black attaches touches will let local parts temperature again rises 300 degrees

Parameters slightly have deviates differences, bottom parts' soft flesh layers fundamentally supports not holds outside that layer brings 800 Megapascals pulling force's crisp shell. Responses not same depths' processing tasks, factories cuts divides not same's discharges stages comes controls destructions degrees.

Rough processing stages every day can burns drop 3 kilograms' steel materials, leaves down's rotten stalls all relies fine processing comes cleans manages. Current one road drops to 2 amperes below, machine uses extremely weak weak's sparks takes front faces that layer 65 micrometers' rotten flesh one little little gnaws drops.

Old practices' fitters hands inside holds 400 grits' oil stones, follows spark machine hits out's cavities bottom parts back forth pushes. Wants pushes drops' not only is naked eye looks sees' burns black layers, must straight towards down grinds drops 0.05 millimeters, straight until takes white mouth layers and heat affects areas all scrapes clean net. Scrapes out's powders takes to analyzes instruments below measures sets, carbon contains amounts high outs normal base materials 1.5 times, all are by high temperatures carbon forms' waste materials.

At dead corners inside, discharges areas only have 2 square millimeters, accumulates carbons discharges not goes out leads to big areas' abnormal discharges. 50 micrometers thick's white mouth layers and micro cracks just original seals not moves ground sticks at side walls on.

Molds installs to forms shapes machines tables on, every injection molds one time, 220 degrees' plastic melts bodies just goes scalds one time cavities. Tight follows 40 degrees' cooling waters again from molds internals' water ways inside crazy brings walks heat amounts.

One cold one hot's back forth alternates, special picks has micro cracks' dead corners down hands. Every opens closes molds 1000 times, 5 micrometers deep's initial cracks just will follows crystal grains' edges towards down extends extends 0.01 millimeters.

Arrives at number 5 ten thousands molds times, cracks grows to 0.5 millimeters, pierces passes heat affects areas' soft flesh layers. 1.2738 steels internals remnants stays' 150 Megapascals machine processing stress runs comes out gathers meets. Two streams huge big's strengths powers stacks adds at together, instantly tears rottens whole piece 80 millimeters thick's mold boards.

Big areas' deep grooves hits finishes sparks after, has experiences' factories will takes steel boards anew anew throws enters retreats fires furnaces. Furnace temperatures precision controls at 480 degrees, holds temperatures 4 hours. Temperatures again high 20 degrees, base materials originally's hardness just will towards down drops.

480 degrees' roasts bakes can takes 800 Megapascals' pulls tears forces unloads drops one extra half. Measures stresses' engineers holds instruments anew anew sweeps one pass, surfaces' pulling forces basically drops to 200 Megapascals' safe lines inside. Cracks loses goes towards outside expands' strengths forces, steel materials survives lives' times extends longs 3 times above.

Welding Repair Failures

Temperatures Controls Not Proper

Welding guns points fires' that one instant, 3200 degrees' high temperatures hard vividly at steel boards on melts opens one puddle iron waters. One piece heavy reaches 450 kilograms' 1.2738 molds big iron blocks just puts at workshops fitters tables on, surroundings air temperatures only have 15 degrees. Three thousands extra degrees' huge big temperatures differences, all presses at not reaches 2 millimeters wide's one stripe small gaps on.

Steel materials internals' carbon elements by roasts gets messily runs, welding guns just one moves walks, surroundings a few hundreds jins' cold iron pimples fast speeds takes heat amounts sucks dry. Comes not in times returns positions' carbon elements by dead dead freezes holds, originally 28 to 34 HRC hardness' steel materials, at welds seams edges one down sons soars rises to 55 HRC.

· Measures temperatures guns wants at welds seams besides 150 millimeters ranges insides extra sweeps a few downs

· Surfaces and deep layers' temperatures differences cannot exceeds 20 degrees

· Rises temperatures speeds presses at every hours 30 to 50 degrees betweens

· Thicknesses exceeds 50 millimeters' iron blocks most less wants at furnaces insides roasts 4 hours

Infrared rays measures temperatures instruments hits at surfaces looks has 220 degrees, towards insides drills two centimeters connects 50 degrees all not arrives. Welds wires melts forms' iron waters drops down goes, instantly burns passes surfaces thin thin's heat layers, heat amounts again by bottom unders' cold irons swallows a clean net.

1.2738 steels insides mixes near 1.2%'s nickels and 2%'s chromiums, compares normal iron pipes spoiled expensive extra much. Repairs pairs finishes at frames on puts two three days all not has moves quietness, fourth day suddenly “pa” one sound huge loud. One stripe 7, 8 centimeters long's cracks follows pairs passes' places self selves collapses opens.

· Pairs one stripe gaps don't exceeds 50 millimeters long

· Stops down comes knocks dregs' times don't exceeds 2 minutes

· Molds surfaces temperatures drops to 200 degrees belows absolute cannots starts arcs

· Lengths exceeds standards' gaps wants divides stages retreats towards back pairs

Pairs one 10 millimeters deep's big pits, comes comes backs backs wants fills enters goes dozens roots welds wires. New covers covers towards ups' high temperatures iron waters, takes bottom unders that one layer again roasts one pass. Temperatures one early mornings loses guards, bottom unders' iron waters just becomes hard again by high temperatures tears opens, naked eyes looks not sees' most deep places early just cracks drops.

Just pairs finishes' places red gets emits brights, cool winds one blows surfaces skins one seconds clocks shrinks shorts thousands parts of threes. Insides still swells, outsides plays lives towards insides squeezes, tears breaks 850 MPa resists pulls strengths' steel materials just follows tears papers sames.

Repairs works frequently follows hands drags one piece thin thin's asbestos cloths covers on, half hours afters surfaces temperatures just drops to 150 degrees. Factories insides rules' resists fires blankets thicknesses must reaches 30 millimeters, must wraps on whole whole three layers. Must lets steels irons every hours only drops 25 degrees, slow slow swallows swallows one straight endures arrives cools thoroughlys.

· Wraps wraps' resists fires blankets wants cans carries holds 800 degrees high temperatures

· Molds on all walks cools waters' holes all blocks deads

· Buries enters dry's holds temperatures sand boxes insides goes

· Stares holds temperatures tables drops to 50 degrees belows again takes outs comes

Thinks takes one dozens kilograms' iron lumps safe steadys drops temperatures, frequently frequently must consumes on one whole nights. Nights drops works pulls drops powers sources not manages, takes ultra-sonic waves flaws detects instruments one sweeps all appears original shapes. Screens ons' waves lines clear clear marks holds 0.02 millimeters' micro small cracks, all are by colds hots alternates rawly rawly tears outs comes.

Takes brings holds dark cracks' molds lifts on injections machines, 150 tons' closes molds forces smashes down comes, all presses at that fragile's corners. A few thousands times machines opens closes, originally heads hairs silks fine's gaps becomes hands fingers nails wides' black grooves. Dozens ten thousands buys comes' molds, all destroys at saves downs' those dozens pieces coals gases fees on.

Gives thicknesses 200 millimeters' bottom boards adds heats, sticks on ceramics adds heats pieces adds on K types heats electricities couples measures temperatures, insides outsides temperatures differences cans dead dead bites at 15 degrees insides. 1.2738 materials qualities bills ons' carbons equivalents writes holds 0.83, numerical values big passes 0.4 just very easy meets colds explodes cracks.

Welds guns extinguishes fires afters' every one seconds, surroundings steels irons' drops temperatures speeds musts sticks at every seconds 1 degrees to 3 degrees betweens. One seconds clocks drops temperatures runs reaches 5 degrees, iron blocks internals all are sparse brokense's cracks. Looks guests not holds passes welds guns, also must understands these dozens hours insides steels irons experiences passes whats kinds' waters deeps fires hots.

Chooses Wrongs Welds Materials

Masters follows hands from grows rusts' iron buckets insides draws outs one roots surfaces plates coppers' ER50-6 welds wires, takes tigers pliers ka chas cuts breaks, stuffs enters TIG argons arcs welds guns' clamps heads insides. One roots sells prices two pieces moneys one kilograms' normal low carbons steels welds wires, bumps on one piece purchases prices every kilograms 65 yuans' Germany produces 1.2738 molds steels.

Normal carbons steels welds wires at melts pools insides cools solidifies afters, hardness supports deads only has 15 to 18 HRC, takes repairs molds' flat files knives slightly one scrapes just cans drops down big pieces irons chips. 1.2738 bases materials outs factories hardness clear clear clear clear marks at 28 to 34 HRC betweens, two ones hardness differs one folds has extras. Heavys reaches 150 tons' injections machines takes near 300 degrees' melts melts gathers propylenes plastics with 120 Megapascals' pressures ruthlessly smashes enters molds cavities, soft collapses collapses' pairs welds areas fundamentally bears not holds forms tons' machines impacts.

Produces lines counts pieces runs not reaches three thousands molds, pairs passes' that piece areas hard vividly towards downs collapses falls 0.05 millimeters. Just hits outs comes' cars vehicles protects bumpers surfaces, welcomes holds lights impressively appears outs one piece hard coins big smalls' dark shadows. 0.05 millimeters' micro smalls concaves pits at polishes plastics pieces on by no limits amplifies big, qualities inspects clerks hands insides' reports wastes bills more saves more thicks. Repairs molds fitters in orders to covers covers collapses falls' loses mistakes, goes storages rooms leads backs one rolls 700 extra pieces moneys' high hardness piles welds medicines cores welds wires.

New welds towards ups' iron waters cools afters hardness one roads soars reaches 58 HRC, compares masters hands insides uses' tungsten steels hits grinds heads still wants hards on a few parts. Fitters tires breaks two roots 800 grits' polishes oils stones, hard is grinds not flats high outs surfaces 0.1 millimeters' welds scars. Injections machines again times closes molds adds pressures, 58 HRC's hard dregs and 30 HRC's bases materials at receives forces times completely pulls tears not reaches one piece goes.

· Chooses uses welds wires' contains carbons amounts must dead dead sticks at 0.35% to 0.45%'s narrow intervals

· Chromiums and nickels elements' matches ratios errors strictly forbids exceeds bases materials chemicals tests bills ons' 0.2%

· Recognizes accurates brings has TIG-P20+Ni marks' special uses molds argons arcs welds wires

· Takes grows rusts drops skins' wastes olds welds wires cuts breaks mixes enters melts pools' operates makes must thoroughly eliminates stops

Steels irons receives heats receives pressures will happens micro smalls' expands deforms, high hardness welds seams' physicals extends stretches rates not reaches 2%, one besidess' 1.2738 original steels cans pulls stretches 15% aboves. Molds one opens one closes alternates receives pressures, two pieces extends stretches natures completely not sames' iron blocks deads lives pulls tears opposites sides. Accompanys follows extremely clears crisps' one sounds breaks tears sounds, welds seams from materials qualities intersects borders places neat brushes brushes ground tears opens one stripe 0.3 millimeters wides' deep grooves.

1.2738 steels materials insides installs exceeds 1%'s nickels elements, all relies it at dozens ten thousands times rushes presses middles maintains holds toughnesses not becomes crisps. Normal welds wires insides connects 0.1%'s nickels all chemicals tests not outs comes, more don't mentions cans defends rottens eats' 2% chromiums elements. High temperatures melts pools takes two kinds eight poles hits not touches' components stirs gathers at one together, divides borders lines on forms one pass extremely ghosts stranges' fragile transitions layers.

Meets arrives needs acids washes bites flowers' works sequences, components not rights' pairs welds areas instantly exposes no remains. Workers takes matches goods' 15% concentrations nitrics acids dissolves liquids brushes at molds cavities surfaces, prepares bites outs cars vehicles insides decorates that kinds fines delicates' rough bodies skins textures. Original factories steels materials two minutes afters rottens eats outs comes 0.02 millimeters deeps' pretty texts routes, pairs passes' places meets arrives acids liquids reacts speeds strange slows, washes drops medicines waters afters presents appears outs one pieces lights balds balds' suddenly standouts bright spots.

Uses 5000 grits' diamonds pastes at pairs goods' molds on hits grinds polishes lights, lights lines hits passes goes cans looks outs obvious' folds shoots differs differences. 1.2738's metals crystals grains arranges lines tight dense, returns lights soft gentle evens. Normal welds wires pairs towards ups' that one pieces crystals bodies rough bigs, polishes gets again brights also will floats outs one layer muddy turbids' thieves lights. Produces outs high lights blacks colors' televisions machines outsides shells, returns lights rates differs 5%, whole pieces plastics boards likes sticks one piece ugly's pairs patches.

One rolls five kilograms installs' Germanys enters mouths 1.2738 special uses welds wires sells prices exceeds 800 yuans, folds gathers down comes every grams not reaches two hairs moneys. One tables 800 tons injections machines' stops machines maintains repairs fees every hours wants burns drops 1500 pieces moneys pure profits. Workshops fitters tables bottoms unders' wastes materials irons buckets insides, throws fulls one piles piles uses wrongs welds wires causes makes whole pieces reports wastes' dozens jins heavys molds inserts pieces. Saves downs dozens pieces moneys consumes materials fees, destroys drops is one tables equipments dozens ten thousands' makes makes hearts bloods.

Residuals Stresses

Molds storages rooms' irons frames ons puts holds one piece just polishes finishes lights' 1.2738 cars vehicles doors boards inserts pieces, quiet quiet lies three months. Not persons goes bumps this piece steels boards, half nights insides workshops suddenly passes comes “peng”'s one sound muffled sounds. Duties shifts fitters runs passes goes hits holds hands electricities tubes illuminates looks, originally lights brights like mirrors' surfaces follows a few days befores pairs passes' edges relies on empties tears opens one stripe 12 centimeters longs' black gaps.

Welds guns at metals surfaces melts opens 3000 degrees' high temperatures irons waters, one roots welds wires becomes liquids fills fulls concaves pits. Irons waters loses goes heats sources starts becomes solids bodies towards insides shrinks shorts, surroundings ups hundreds jins ice colds hard solids' bases materials dead dead sticks holds four surroundings borders boundaries, one millimeters all not allows its towards backs shrinks.

Two streams pure's physicals pulls tears at metals deeps places deads knocks. Not reaches 5 millimeters wides' gaps gaps surroundings, towards insides tears pulls' forces ways soars reaches frightens persons' 600 Megapascals. At one piece fingers nails covers big smalls' steels boards areas on hangs fulls 60 tons heavys irons lumps, equals sames to this stream no shapes' destroys breaks forces.

“Just burns finishes' irons blocks looks holds tight silks meets gaps, puts on CNC processes centers one knife cuts down goes, bottom unders' materials on spots warps rises comes 0.15 millimeters. Insides' dark strengths big gets fundamentally presses not holds.” Pairs repairs twenties extras years molds' old Fu holds stuffs rulers inserts enters gaps gaps insides not stops shakes heads.

Injections machines' cannons tubes takes 150 degrees' boiling hots plastics hits enters molds cavities bodies, 1200 tons' locks molds forces heavy heavy smashes down comes. Steels materials outsides shells bears receives holds machines applies adds' dozens Megapascals squeezes presses, internals holds backs holds a few hundreds Megapascals' tears cracks feels. Insides outsides two streams forces amounts one bumps heads, on spots dry pierces 1.2738 steels materials 850 Megapascals' resists pulls bottoms lines.

Molds factories in orders to saves downs holds temperatures returns fires furnaces one nights up approximately 300 pieces moneys' industrials electricities fees, welds finishes takes big powers winds fans facing holds fierce blows drops temperatures. Long reaches 12 hours' goes stresses retreats fires works sequences by hard vividly cuts drops, that stream cans takes steels boards pulls bends' forces amounts forever leaves at this piece 400 extra kilograms' irons blocks insides.

· Thicknesses every adds adds 25 millimeters, enters furnaces roasts' times must thunders hits not moves ground towards ups adds 2 hours

· Furnaces temperatures controls manages cabinets' points needles wants dead dead sticks at 480 degrees to 520 degrees betweens

· Drops temperatures outs furnaces that one moments, steels boards surfaces real measures temperatures strictly forbids exceeds 50 degrees

· Leaves opens fires furnaces afters one laws buries enters drys' holds temperatures sands boxes insides slow slow releases frees heats amounts

Takes brings has dark strengths' steels blocks moves on slow walks silks cuts divides machines, 0.18 millimeters roughs molybdenums silks just cuts enters pairs repairs areas edges not reaches two centimeters. Originally flats neats' cuts gaps two sides receives forces instantly loses balances, metals boards fierce ground towards middles one clamps.

Returns fires furnaces' temperatures turns knobs is a fine fines lives. Turns reaches 550 degrees aboves goes roasts, 1.2738 original factories brings holds' 32 HRC hardnesses will likes snows collapses sames towards downs drops, outs furnaces afters softs gets connects one roots coppers nails all cans at on faces scratches outs prints sons. Temperatures not reaches 450 degrees, puts at insides drys roasts ten hours completely unloads not drops one stars half points internals' pulls forces.

“Uses 5000 grits' diamonds polishes lights pastes follows pairs repairs places hits grinds, high folds amplifies big glasses belows cans looks arrives one rows extremely fine denses' nets shapes hairs silks textures. Metals internals' pulls stretches forces hard vividly takes surfaces skins arranges lines tight denses' crystals grains gives tears loose.”

Olds one generations fitters' makes methods is takes pairs goods' irons blocks throws at workshops outsides' muds grounds insides, allows frees winds blows suns shines big half years. Relies holds a few thousands hours' natures environments goes slow slow digests this stream dark strengths. Nows' orders bills hands periods only has not reaches 20 days, enters electricities furnaces high temperatures adds heats becomes onlys' points hopes.

A few hundreds Megapascals' pulls stretches forces at 500 degrees' high temperatures belows slow slow looses relaxes, micro views arranges lines mistakes chaos' irons atoms takes advantages receives heats expands deforms' gaps gaps, one little little moves backs selves should stays' positions. One piece 100 millimeters thicks' big molds blocks, stuffs enters furnaces insides less speaks wants solid solid real reals ground muffles on 8 hours.

Not goes fires furnaces insides walks one meets, polishes lights masters spends three days three nights grinds outs comes' mirrors surfaces one on machines all leaks stuffings. Hits outs fronts five tens plastics pieces looks holds completes beautys not flaws, hits reaches number one hundreds, divides shapes faces suddenly by supports opens 0.05 millimeters' gaps gaps. Hits outs comes' PP materials qualities plastics pieces surroundings edges instantly flies outs one circles pricks hands' hairs edges.

Flaws detects uses' magnetics powders evens evens scatters at fitters tables ons, sprays on one layer appears images liquids. One stripe originally hides at surfaces skins belows 2 millimeters deeps' micro smalls cracks gaps receives internals longs periods pulls tears, amplifies bigs becomes wides 0.1 millimeters, deeps reaches 15 millimeters' breaks layers. Ups ten thousands pieces moneys' specials kinds steels materials connects sames half months' lathes mills planes grinds persons works fees, at this stripe black lines faces fronts all becomes wastes irons.