{"id":2183,"date":"2018-10-13T13:42:36","date_gmt":"2018-10-13T10:42:36","guid":{"rendered":"http:\/\/mekanikelektriktesisat.com\/?p=2183"},"modified":"2018-10-13T13:42:36","modified_gmt":"2018-10-13T10:42:36","slug":"malzeme-dokme-demir","status":"publish","type":"post","link":"https:\/\/benga.pro\/index.php\/2018\/10\/13\/malzeme-dokme-demir\/","title":{"rendered":"Malzeme – D\u00f6kme Demir"},"content":{"rendered":"

Daha \u00f6nce do\u011fada en \u00e7ok bulunan metallerden olan demirden \u00fcretilen \u00e7elik<\/a> hakk\u0131nda bir yaz\u0131 haz\u0131rlam\u0131\u015ft\u0131k. Bu yaz\u0131m\u0131zda ise demirden elde edilen di\u011fer bir \u00fcr\u00fcn olan d\u00f6kme demirden bahsedece\u011fiz.<\/p>\n

\u00d6ncelikle pik demirin ne oldu\u011funu hat\u0131rlayal\u0131m:<\/p>\n

\u00c7elik yada d\u00f6kme demir \u00fcretiminin ilk a\u015famas\u0131 demir cevherinin i\u015flenmesidir. Demir cevheri, y\u00fcksek f\u0131r\u0131nlarda (Blast furnace) i\u015flenir ve pik demir (pig iron)<\/strong> \u00fcretilir. Pik demir bu haliyle kullan\u0131lmaya pek elveri\u015fli bir mamul olmay\u0131p \u00e7elik ve d\u00f6kme demir \u00fcretimi i\u00e7in kullan\u0131lan bir yar\u0131 mamuld\u00fcr.  (\u201cPig\u201d \u0130ngilizcede \u201cdomuz\u201d demektir. Pik demirin \u00fcretiminde \u00fcr\u00fcn kal\u0131b\u0131n\u0131n domuza benzemesinden \u00f6t\u00fcr\u00fc bu isim kullan\u0131lm\u0131\u015ft\u0131r.) Pik demirin karbon oran\u0131 %4 civar\u0131ndad\u0131r. Pik demire ayn\u0131 zamanda font demir, ham demir<\/strong> de denir.<\/p>\n

Elde edilen pik demirde e\u011fer mangan (Mn) fazla ise beyaz pik demir<\/strong>, silisyum(Si) fazla ise esmer pik demir<\/strong> olur. Beyaz pik demir, \u00e7elik \u00fcretimi i\u00e7in kullan\u0131l\u0131rken esmer pik demir, d\u00f6kme demir par\u00e7alar\u0131n \u00fcretimi i\u00e7in kullan\u0131l\u0131r<\/p>\n

\n

1. D\u00f6kme Demir (Cast Iron)<\/h4>\n

Pik demir olarak \u00fcretilen ara mamuller, kupol ocaklarda eritilerek i\u00e7 yap\u0131s\u0131nda bulunan karbon %2 ila\u0302 4 aras\u0131na d\u00fc\u015f\u00fcr\u00fcl\u00fcr. Sadece karbon azalt\u0131m\u0131 d\u00f6kme demirin, end\u00fcstrinin ihtiya\u00e7lar\u0131na cevap verecek nitelikte de\u011fildir. Bu y\u00fczden ba\u015fka katk\u0131 elementleri de ilave edilerek, de\u011fi\u015fik ama\u00e7lar i\u00e7in kullan\u0131labilir d\u00f6kme demirler \u00fcretilir.<\/p>\n

B\u00fct\u00fcn d\u00f6kme demirlerin yap\u0131s\u0131nda genel olarak \u015fu bile\u015fenler mevcuttur.
\nKarbon(C)           % 2 – 4
\nSilisyum (Si)       % 0,4 – 3
\nManganez(Mn)  % 0,4 – 0,8
\nFosfor(P)             % 0,1 – 0,8<\/p>\n

D\u00f6kme demirler; sertlik, iyi tala\u015fl\u0131 i\u015flenebilirlik, m\u00fckemmel basmaya dayanma, a\u015f\u0131nmaya mukavemet ve kat\u0131l\u0131k (e\u011filmezlik) dahil, \u00f6zellik de\u011fi\u015fkenli\u011fine sahip olup metallerin en ucuzudurlar.<\/p>\n

\"trakyad\u00f6k\u00fcm.JPG\"
\nD\u00f6kme demirleri \u00e7eliklerden ay\u0131ran \u00f6zellikler aras\u0131nda a\u015fa\u011f\u0131dakiler \u00e7ok belirgindir.
\n– D\u00f6kme demirler s\u00fcnek de\u011fillerdir; kopmada uzama g\u00f6stermezler; d\u00f6v\u00fclemezler, haddelenemezler.
\n– Is\u0131t\u0131ld\u0131klar\u0131nda hamurla\u015fmazlar, kat\u0131 halden do\u011fruca s\u0131v\u0131 hale d\u00f6n\u00fc\u015f\u00fcrler. So\u011furken de
\nbunun tersi olur, yani s\u0131v\u0131 halden do\u011fruca kat\u0131 hale ge\u00e7erler.<\/p>\n

D\u00f6kme demirlerin mekanik \u00f6zelliklerini en fazla etkileyen bile\u015fen karbon<\/strong>dur. Yap\u0131daki karbon, ya bile\u015fik halde (sementit<\/strong>) yada serbest halde (grafit<\/strong>) olarak bulunur. Grafitlerin \u015fekli, miktar\u0131 d\u00f6kme demirlerin mukavemet ve s\u00fcnekli\u011fini etkiler. Buna g\u00f6re de d\u00f6kme demirler, parlat\u0131lm\u0131\u015f y\u00fczeylerde g\u00f6r\u00fclebilen grafit karakteristi\u011fine g\u00f6re
\ns\u0131n\u0131fland\u0131r\u0131labilir:<\/p>\n\n\n\n\n\n\n\n\n
D\u00f6kme demirlerin kimyasal kompozisyonlar\u0131 (%)<\/strong><\/td>\n<\/td>\n<\/td>\n<\/tr>\n
<\/td>\nToplam C<\/strong><\/td>\nSi<\/strong><\/td>\nS<\/strong><\/td>\nP<\/strong><\/td>\nMn<\/strong><\/td>\nFe<\/strong><\/td>\n<\/tr>\n
Beyaz<\/strong><\/td>\n2,5-4%<\/strong><\/td>\n0,4-1,6%<\/strong><\/td>\n0,15%<\/strong><\/td>\n0,4%<\/strong><\/td>\n0,3-0,8%<\/strong><\/td>\nKalan<\/strong><\/td>\n<\/tr>\n
Gri<\/strong><\/td>\n2-4%<\/strong><\/td>\nmin 1%<\/strong><\/td>\n0,2%<\/strong><\/td>\n0,6%<\/strong><\/td>\nmax 1%<\/strong><\/td>\nKalan<\/strong><\/td>\n<\/tr>\n
Temper<\/strong><\/td>\n2-3%<\/strong><\/td>\n0,9-1,8%<\/strong><\/td>\nmax 0,2%<\/strong><\/td>\nmax 0,2%<\/strong><\/td>\n0,2-1,25%<\/strong><\/td>\nKalan<\/strong><\/td>\n<\/tr>\n
K\u00fcresel<\/strong><\/td>\n3,2-4,1%<\/strong><\/td>\n1,8-2,8%<\/strong><\/td>\nmax 0,03%<\/strong><\/td>\nmax 0,1%<\/strong><\/td>\nmax 0,8%<\/strong><\/td>\nKalan<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

<\/h4>\n

1.1. Gri D\u00f6kme Demir (Gray Cast Iron)<\/h4>\n

Serbest karbonlar\u0131n grafit yapraklar\u0131 \u015fekilde olu\u015ftu\u011fu demir-karbon-silisyum ala\u015f\u0131mlar\u0131na gri d\u00f6kme demir<\/strong> denir. Lamel (\u00c7ubuk) grafitli d\u00f6kme demir<\/strong> de denilir. Gri d\u00f6kme demir, kal\u0131ba d\u00f6k\u00fclen ergimi\u015f ham demirin yava\u015f so\u011fumas\u0131yla elde edilir. D\u00f6k\u00fcm so\u011furken malzeme i\u00e7indeki karbon grafit \u00e7ubuklar\u0131 \u015feklinde \u00e7\u00f6kelir. Bu d\u00f6kme demirlere gri denmesinin nedeni; k\u0131r\u0131lma y\u00fczeylerindeki gri g\u00f6r\u00fcn\u00fcmd\u00fcr . Gri d\u00f6kme demirde yap\u0131da bile\u015fke halde bulunan karbon %0.8\u2019den daha d\u00fc\u015f\u00fckt\u00fcr, kalan karbon grafit \u00e7ubuklar\u0131 (lamel) \u015feklindedir.<\/p>\n

Gri d\u00f6kme demir en yayg\u0131n kullan\u0131lan d\u00f6kme demir t\u00fcr\u00fcd\u00fcr ve gerekli \u00f6nlemler al\u0131narak (\u00f6n \u0131s\u0131tma ve kaynak sonras\u0131 so\u011fuma h\u0131z\u0131 gibi) kaynaklanabilir. Gri d\u00f6kme demirler makine par\u00e7alar\u0131 ve otomotiv end\u00fcstrisinde yan\u0131 s\u0131ra tesisat sekt\u00f6r\u00fcnde bas\u0131n\u00e7l\u0131 veya bas\u0131n\u00e7s\u0131z ortamlarda \u00e7al\u0131\u015fmak i\u00e7in farkl\u0131 tiplerde boru, vana, flan\u015f, ba\u011flant\u0131 par\u00e7alar\u0131 gibi malzemelerin \u00fcretiminde de yayg\u0131n olarak kullan\u0131l\u0131r.<\/p>\n

Gri d\u00f6kme demir mikro yap\u0131s\u0131<\/em><\/p>\n

\"gri<\/p>\n

1.2. K\u00fcresel D\u00f6kme Demir (Ductile Cast Iron)<\/h4>\n

K\u00fcresel d\u00f6kme demir (Sfero D\u00f6k\u00fcm)<\/strong> kimyasal kompozisyonu gri d\u00f6kme demirinkinin ayn\u0131s\u0131 olmas\u0131na ra\u011fmen mukavemet ve s\u00fcneklikte \u00e7eliklere benzerler, fakat \u00fcretim \u015fekli farkl\u0131d\u0131r. Gri d\u00f6kme demirlerde grafit lamellerinin \u015fekli \u00e7atlak olu\u015fturma \u00f6zelli\u011finden dolay\u0131 gri d\u00f6kme demirin mukavemetini , toklu\u011funu ve s\u00fcnekli\u011fini d\u00fc\u015f\u00fcren ana etkendir. Grafitin lamelli de\u011fil de k\u00fcresel olmas\u0131 daha y\u00fcksek mukavemet ve s\u00fcneklik sa\u011flar. B\u00f6ylece d\u00f6kme \u00e7eliklerin mukavemet ve s\u00fcneklik \u00f6zellikleriyle, d\u00f6kme demirlerin d\u00fc\u015f\u00fck maliyet, a\u015f\u0131nma direnci ve \u00fczerine uygulanan kuvvetleri emme karakteristikleri birle\u015fir.<\/p>\n

Su, kanalizasyon ve bas\u0131n\u00e7l\u0131 borular, ba\u011flant\u0131lar, vanalar ve pompalar k\u00fcresel d\u00f6kme
\ndemirden yap\u0131labilir . Bu \u00fcr\u00fcnlerin k\u00fcresel d\u00f6kme demirden yap\u0131lmas\u0131n\u0131n avantajlar\u0131
\ntoklu\u011funun ve kaynak kabiliyetinin gri d\u00f6kme demirlere g\u00f6re daha iyi olmas\u0131d\u0131r. K\u00fcresel d\u00f6kme demir borular \u00e7o\u011funlukla kaynaklanarak \u00fcretilirler.<\/p>\n

K\u00fcresel d\u00f6kme demir mikro yap\u0131s\u0131<\/em><\/p>\n

\"sferod\u00f6k\u00fcm.JPG\"<\/p>\n

1.3. Beyaz(K\u0131r) D\u00f6kme Demir (White Cast Iron)<\/h4>\n

K\u0131r d\u00f6kme demir, kal\u0131p i\u00e7ine d\u00f6k\u00fclen demirin h\u0131zl\u0131 so\u011fuma sonucunda karbonun yap\u0131n\u0131n i\u00e7inde kalmas\u0131 halinde olu\u015fur. So\u011fuma h\u0131z\u0131 gri d\u00f6kme demirde oldu\u011fu gibi
\nkarbonun grafit lamelleri \u015feklinde \u00e7\u00f6kelmesine izin vermez fakat karbon, demir, krom
\nyada molibdenle birle\u015ferek karb\u00fcr olu\u015fturur. Olu\u015fan demir karbon (Fe3C-sementit), sert ve k\u0131r\u0131lgand\u0131r . D\u00f6kme demir \u00e7o\u011funlukla bu sementit par\u00e7ac\u0131klar\u0131ndan k\u0131r\u0131l\u0131r. K\u0131r\u0131k
\ny\u00fczeye bak\u0131ld\u0131\u011f\u0131nda a\u00e7\u0131k yada ak renkli g\u00f6r\u00fcl\u00fcr, bu nedenle bunlara beyaz d\u00f6kme demir <\/strong>denir.  D\u00f6k\u00fcmde y\u00fcksek oranda demir-karb\u00fcr olu\u015fur ve yap\u0131, gri d\u00f6kme demir kimyasal kompozisyonuna sahip olunmas\u0131na ra\u011fmen gri d\u00f6kme demire g\u00f6re daha sert ve k\u0131r\u0131lgan olur. Beyaz d\u00f6kme demirler normalde kaynak edilemezler \u00e7\u00fcnk\u00fc, ana metalde olu\u015fan \u0131s\u0131l gerilmeleri kar\u015f\u0131layabilmek i\u00e7in gerekli s\u00fcnekli\u011fe sahip de\u011fildirler.<\/p>\n

A\u015f\u0131nmaya dayan\u0131kl\u0131 olmas\u0131 istenilen kam mili ve hadde silindirleri, beyaz d\u00f6kme demirle yap\u0131lan makine par\u00e7alar\u0131ndan baz\u0131lar\u0131d\u0131r.  Normal \u015fartlarda i\u015flenmesi olanaks\u0131z olan beyaz d\u00f6kme demir, ancak ta\u015flanarak \u015fekillendirilebilir.<\/p>\n

Beyaz d\u00f6kme demir mikro yap\u0131s\u0131<\/em><\/p>\n

\"beyaz<\/p>\n

1.4. Temper D\u00f6kme Demir (Malleable Cast Iron)<\/h4>\n

Az karbonlu \u00e7eliklerin \u00f6zelliklerini g\u00f6steren ve beyaz d\u00f6kme demirin \u0131s\u0131l baz\u0131 i\u015flemlerden ge\u00e7irilmesi (Basit\u00e7e, beyaz d\u00f6kme demirin 900 \u2013 950 \u00b0C\u2019 ye kadar \u0131s\u0131t\u0131lmas\u0131 ve yava\u015f so\u011futulmas\u0131 diyebiliriz) sonucunda \u00fcretilen d\u00f6kme demir t\u00fcr\u00fcd\u00fcr. Bu y\u00f6n\u00fcyle gri d\u00f6kme demirden pahal\u0131, \u00e7elikten ucuzdur.<\/p>\n

Temper d\u00f6kme demirlerde karbon lameller (\u00e7ubuk) \u015feklinde de\u011fil de k\u00fcresel oldu\u011fu i\u00e7in bir miktar s\u00fcnekli\u011fi vard\u0131r. Temper d\u00f6kme demir, beyaz d\u00f6kme demir veya gri d\u00f6kme
\ndemirden daha toktur ve uygun bir miktar e\u011filebilir. Gri d\u00f6kme demir az miktarda bir e\u011filme sonucunda k\u0131r\u0131l\u0131r. Beyaz d\u00f6kme demir de cam gibidir, hi\u00e7 e\u011filmez, k\u0131r\u0131l\u0131r. Bu d\u00f6kme demirlerde de mukavemet ve s\u00fcneklik metalurjik yap\u0131ya ba\u011fl\u0131 oldu\u011fu gibi, serbest grafitin da\u011f\u0131l\u0131m\u0131na da ba\u011fl\u0131d\u0131r.<\/p>\n

Temper d\u00f6kme demirler kaynak yap\u0131l\u0131rken, kaynak metalinin so\u011fumas\u0131 s\u0131ras\u0131nda \u0131s\u0131l i\u015flemin faydal\u0131 etkisi ortadan kalkar ve h\u0131zl\u0131 so\u011fuma sonucunda k\u0131r\u0131lgan bir yap\u0131 (chilling) g\u00f6r\u00fcl\u00fcr. Bunun i\u00e7in kaynak b\u00f6lgesi, kaynaktan sonra tekrar \u0131s\u0131l i\u015fleme tabi tutularak temper d\u00f6kme demirin yap\u0131s\u0131 elde edilmelidir.<\/p>\n

Temper d\u00f6kme demirler flan\u015flarda, borularda, ba\u011flant\u0131 ve vana par\u00e7alar\u0131nda
\nkullan\u0131l\u0131r. Bir \u00e7ok otomobil par\u00e7as\u0131, kompres\u00f6r krank mili ve g\u00f6be\u011fi, transmisyon ve
\ndiferansiyel par\u00e7alar\u0131, ba\u011flant\u0131 \u00e7ubuklar\u0131 ve universal ba\u011flant\u0131lar temper d\u00f6kme demirden \u00fcretilirler.<\/p>\n

Karbonu azalt\u0131lm\u0131\u015f ve\/veya meydana gelebilecek grafitin bi\u00e7imi nedeni ile i\u00e7 \u00e7entik etkisi hafifletilmi\u015f olan temper d\u00f6k\u00fcm, dayan\u0131m ve \u015fekil de\u011fi\u015ftirme \u00f6zellikleri bak\u0131m\u0131ndan beyaz(k\u0131r) d\u00f6k\u00fcm ile \u00e7elik d\u00f6k\u00fcm aras\u0131nda yer al\u0131r.<\/p>\n

Temper d\u00f6kme demir mikro yap\u0131s\u0131<\/em><\/p>\n

\"temper<\/p>\n

K\u0131r\u0131k y\u00fczeyi g\u00f6r\u00fcn\u00fcm\u00fcne g\u00f6re beyaz ve siyah temper<\/strong> olarak 2 \u00e7e\u015fidi vard\u0131r.<\/p>\n

– Beyaz Temper D\u00f6kme Demir  (Whiteheart Malleable Cast Iron)<\/strong><\/p>\n

Ham temper d\u00f6k\u00fcm\u00fcn 1000 \u00baC \u2018de 80 saat s\u00fcre ile oksitleyici ortamda temperlenmesi ile elde edilir.  Beyaz temper d\u00f6kme \u00fcr\u00fcnleri \u00e7o\u011funlukla ince etlidir.<\/p>\n

-Siyah Temper D\u00f6kme Demir  (Blackheart Malleable Cast Iron)<\/strong>
\nHam temper; azot\u00e7a zengin atmosfer alt\u0131nda gaz s\u0131zd\u0131rmaz f\u0131r\u0131nlarda temperlenir. D\u00f6k\u00fcm par\u00e7an\u0131n t\u00fcm kesitinde temper karbonu i\u00e7eren ferritik bir i\u00e7 yap\u0131 elde
\nedildi\u011fin mekanik \u00f6zellikler et kal\u0131nl\u0131\u011f\u0131na ba\u011fl\u0131 de\u011fildir.<\/p>\n

\n

2. D\u00f6kme demirlerin k\u0131sa g\u00f6sterili\u015fi<\/h4>\n

D\u00f6kme demirler i\u00e7in \u00fclkemizde tesisat sekt\u00f6r\u00fcnde \u00e7o\u011funlukla EN 1560 standard\u0131na g\u00f6re tariflenen k\u0131sa g\u00f6sterim ile Alman DIN normuna g\u00f6re tariflenen g\u00f6sterimler kullan\u0131lmaktad\u0131r.<\/p>\n

\u00d6rne\u011fin, sfero d\u00f6k\u00fcm (K\u00fcresel D\u00f6kme demir) bir vanan\u0131n teknik f\u00f6y\u00fcnde i\u00e7in DIN normuna g\u00f6re GGG40 yazarken EN Normuna g\u00f6re EN-GJS-400-15 yazar.<\/p>\n

EN 1560<\/strong> standard\u0131na buraya t\u0131klayarak <\/a>ula\u015fabilirsiniz. Bu standartta d\u00f6kme demirlerin nas\u0131l k\u0131sa g\u00f6sterili\u015fi detayl\u0131 olarak ifade edilmektedir. Ama k\u0131saca \u015f\u00f6yle \u00f6zetleyebiliriz.<\/p>\n

Bir d\u00f6kme demirin g\u00f6sterili\u015finde 6 tane kademe vard\u0131r.<\/p>\n

Kademe 1’de “EN-” ifadesi yer al\u0131r.<\/p>\n

Kademe 2’de D\u00f6kme demir sembol\u00fc yer al\u0131r. (“GJ” ifadesi yer al\u0131r  G:D\u00f6k\u00fcm J:Demir)<\/p>\n

Kademe 3’de D\u00f6kme demir grafit yap\u0131s\u0131 yer al\u0131r.<\/p>\n

Kademe 4’de D\u00f6kme demir mikro yada makro yap\u0131s\u0131 yer al\u0131r.<\/p>\n

Kademe 5’de D\u00f6kme demir kimyasal yada mekanik \u00f6zellik bilgisi yer al\u0131r.<\/p>\n

Kademe 6’da \u0130lave bilgi yer al\u0131r.<\/p>\n

 <\/p>\n

3. kademede yer alan grafit yap\u0131s\u0131 k\u0131saltmalar\u0131 \u015f\u00f6yledir.<\/p>\n

L:<\/strong> Lamel grafitli<\/p>\n

S:<\/strong>K\u00fcresel Grafitli<\/p>\n

M:<\/strong>Temper D\u00f6k\u00fcm   (MB:<\/strong> Siyah Temper d\u00f6k\u00fcm, MW:<\/strong>Beyaz temper d\u00f6k\u00fcm)<\/p>\n

V:<\/strong>Vermicular<\/p>\n

N:<\/strong>Grafitsiz<\/p>\n

Y:<\/strong> \u00d6zel Yap\u0131<\/p>\n

Bu isimlendirmede daha \u00e7ok kademe 1,2,3 ve 5 kullan\u0131l\u0131r. \u00d6rne\u011fin EN-GJL-250 ifadesinden 250MPa \u00e7ekme mukavemetine sahip lamel grafitli (gri) d\u00f6kme demir anla\u015f\u0131lmaktad\u0131r.<\/p>\n

 <\/p>\n

Alman DIN normunda<\/strong> ise, k\u0131saltma d\u00f6kme demirin grafit yap\u0131s\u0131n\u0131 ifade eden harf dizisinden sonra \u00e7ekme mukavemetini veren bir say\u0131dan(kgf\/mm2) olu\u015fur.<\/p>\n

Gri D\u00f6k\u00fcm GG, K\u00fcresel D\u00f6k\u00fcm GGG, Beyaz d\u00f6k\u00fcm GH, Temper d\u00f6k\u00fcm ise GT ‘dir.<\/p>\n

Mesela GG20 ile ifade edilen bir d\u00f6kme demir gri d\u00f6kme demir olup 20kgf\/mm2 \u00e7ekme mukavemetine sahiptir.<\/p>\n

\n

3. Tesisat sekt\u00f6r\u00fcndeki baz\u0131 d\u00f6k\u00fcm malzeme \u00f6rnekleri<\/h4>\n

D\u00f6k\u00fcm Vana ve Armat\u00fcrler<\/strong><\/em><\/span><\/p>\n

Bir vana \u00fcreticisinin katalo\u011funu inceledi\u011fimizde temelde 2 tane d\u00f6k\u00fcm cinsi ile kar\u015f\u0131la\u015f\u0131yoruz. GG25 (EN-GJL-250) ve GGG40 (EN-GJS 400-15).<\/p>\n

Yukar\u0131daki b\u00f6l\u00fcmlerden anlat\u0131lanlardan hareketler GG25 i\u00e7in gri d\u00f6kme demir (lamel grafitli) ve 25 kgf\/mm2 \u00e7ekme mukavmetine sahip vana malzemesinden bahsedildi\u011fini anlar\u0131z. GGG40’dan ise k\u00fcresel grafitli (sfero d\u00f6k\u00fcm) d\u00f6kme demir ve 40kgf\/mm2 \u00e7ekme mukavemetli vanadan bahsedildi\u011fini anlar\u0131z. Bu iki malzeme aras\u0131ndaki farktan, GGG40’\u0131n daha zorlay\u0131c\u0131 \u00e7al\u0131\u015fma \u015fartlar\u0131na (y\u00fcksek bas\u0131nca, vs.) dayanabildi\u011fini bu sebeple fiyat\u0131n\u0131n daha y\u00fcksek olaca\u011f\u0131 ortaya \u00e7\u0131kar.<\/p>\n

Avrupa normuna g\u00f6re k\u0131sa g\u00f6sterili\u015fleri analiz edersek GJL’den lamel grafitli (gri) d\u00f6kme demir ve 250N\/mm2 \u00e7ekme mukavemetini anlar\u0131z, GJS’den ise sfero d\u00f6k\u00fcm (k\u00fcresel d\u00f6kme demir) ve 400N\/mm2 \u00e7ekme mukavemetini anlar\u0131z.<\/p>\n

\"d\u00f6k\u00fcm<\/p>\n

Fittings (Boru Ba\u011flant\u0131 Par\u00e7alar\u0131)<\/strong><\/em><\/span><\/p>\n

D\u00f6kme demir boru ba\u011flant\u0131 par\u00e7lar\u0131n\u0131n teknik f\u00f6y\u00fcn\u00fc inceledi\u011fimizde malzeme i\u00e7in EN-GJMB-350-10 bilgisinin verildi\u011fini g\u00f6r\u00fcyoruz. Buradaki MB ifadesinden boru ba\u011flant\u0131 par\u00e7as\u0131n\u0131n siyah temper d\u00f6k\u00fcm oldu\u011funu ve 350N\/mm2 \u00e7ekme mukavemetine haiz oldu\u011funu s\u00f6yleriz. (10 rakam\u0131 ise % olarak uzamay\u0131 g\u00f6sterir.) \"fittings.JPG\"<\/p>\n

 <\/p>\n

Pik D\u00f6k\u00fcm Boru<\/strong><\/em><\/span><\/p>\n

“Pik d\u00f6k\u00fcm” ifadesi “Pik demir” ifadesi ile kar\u0131\u015fabilir. Daha \u00f6nce anlatm\u0131\u015ft\u0131k ama tekrar vurgulamakta fayda var. Pik demir, gerek \u00e7eli\u011fin gerekse d\u00f6kme demirin \u00fcretiminde kullan\u0131l\u0131r ve demir cevherinden elde edilen bir ara mamuld\u00fcr. Pik d\u00f6k\u00fcm<\/strong> ise dilimizde daha \u00e7ok gri d\u00f6kme demir (lamel grafitli) ifadesinin yerine kullan\u0131l\u0131r.<\/p>\n

\u015eimdi buradan hareketle pik d\u00f6k\u00fcm boru i\u00e7in bir \u00fcreticinin teknik f\u00f6y\u00fcne bakt\u0131\u011f\u0131m\u0131zda EN-GJL-150 ifadesini g\u00f6r\u00fcyoruz. Buradan pik d\u00f6k\u00fcm borunun imalat\u0131nda \u00e7ekme mukavemeti 150kgf\/mm2 olan gri d\u00f6kme demir kullan\u0131ld\u0131\u011f\u0131n\u0131 anlar\u0131z. Teknik f\u00f6yde ayn\u0131 zamanda GG15 olarak DIN normunda da ifade yer alabilir. GG ifadesinden gri d\u00f6kme demir, 15 ifadesinden de \u00e7ekme mukavemetinin 15N\/mm2 oldu\u011funu anlar\u0131z.<\/p>\n

\"pikboru.JPG\"<\/p>\n

 <\/p>\n

D\u00fcktil Demir Boru<\/strong><\/em><\/span><\/p>\n

D\u00fcktil borular, i\u00e7me suyu hatlar\u0131nda kullan\u0131lmak \u00fczere santrif\u00fcj d\u00f6k\u00fcm tekni\u011fi ile \u00fcretilmi\u015f sfero d\u00f6kme demir (k\u00fcresel grafitli d\u00f6kme demir) borulard\u0131r. Boru \u00fcreticisinin katalo\u011funda yer alan EN-GJS-420 ifadesinden borunun k\u00fcrsel d\u00f6kme demir ve 420N\/mm2 \u00e7ekme mukavemetine sahip oldu\u011funu anlar\u0131z.<\/p>\n

\"d\u00fcktilboru.JPG\"<\/p>\n

D\u00f6k\u00fcm G\u00f6vdeli Pompalar<\/strong><\/em><\/span><\/p>\n

T\u0131pk\u0131 vanalarda oldu\u011fu gibi pompa \u00fcretcisinin katalo\u011funu inceledi\u011fimizde temelde 2 tane d\u00f6k\u00fcm cinsi vard\u0131r. . GG25 (EN-GJL-250) ve GGG40 (EN-GJS 400-15).<\/p>\n

GG25 i\u00e7in gri d\u00f6kme demir (lamel grafitli) ve 25 kgf\/mm2 \u00e7ekme mukavmetine sahip pompa g\u00f6vdesinden bahsedilirken GGG40 ile k\u00fcresel grafitli (sfero d\u00f6k\u00fcm) d\u00f6kme demir ve 40kgf\/mm2 \u00e7ekme mukavemetli pompa g\u00f6vdesinden bahsedilir.<\/p>\n

\"pompa\"<\/p>\n

 <\/p>\n

\n

Kaynaklar<\/strong><\/p>\n

https:\/\/magmaweld.com.tr\/Content\/UserFiles\/OerlikonKutuphanesi\/Dokme_demirler.pdf<\/p>\n

https:\/\/www.makinaegitimi.com\/malzeme-bilgisi\/dokme-demirler-ve-dokme-demir-cesitleri.html<\/p>\n

\n
http:\/\/www.oerlikon.com.tr\/files\/dokme_demirler_ve_dokme_demirlerin_kaynagi.pdf<\/div>\n
<\/div>\n
<\/div>\n<\/div>\n
http:\/\/www.steelnumber.com<\/div>\n
<\/div>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

Daha \u00f6nce do\u011fada en \u00e7ok bulunan metallerden olan demirden \u00fcretilen \u00e7elik hakk\u0131nda bir yaz\u0131 haz\u0131rlam\u0131\u015ft\u0131k. Bu yaz\u0131m\u0131zda ise demirden elde edilen di\u011fer bir \u00fcr\u00fcn olan d\u00f6kme demirden bahsedece\u011fiz. \u00d6ncelikle pik demirin ne oldu\u011funu hat\u0131rlayal\u0131m: \u00c7elik yada d\u00f6kme demir \u00fcretiminin ilk a\u015famas\u0131 demir cevherinin i\u015flenmesidir. Demir cevheri, y\u00fcksek f\u0131r\u0131nlarda (Blast furnace) i\u015flenir ve pik demir (pig iron) \u00fcretilir.… Malzeme – D\u00f6kme Demir<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":3582,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","_themeisle_gutenberg_block_has_review":false,"footnotes":""},"categories":[5,1,7,49],"tags":[211,209,210,212,213,214,215,216,217,218],"class_list":["post-2183","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-elektrik-tesisat","category-genel","category-mekanik-tesisat","category-teknik-konular","tag-beyaz-dokum","tag-celik","tag-demir","tag-dokum","tag-en-1560","tag-malzeme","tag-pik","tag-pik-dokum","tag-sfero-dokum","tag-temper-dokum"],"_links":{"self":[{"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/posts\/2183","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/comments?post=2183"}],"version-history":[{"count":0,"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/posts\/2183\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/benga.pro\/index.php\/wp-json\/"}],"wp:attachment":[{"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/media?parent=2183"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/categories?post=2183"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/benga.pro\/index.php\/wp-json\/wp\/v2\/tags?post=2183"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}