< PreviousTEKNOLOGI LAS KAPAL C2WES.........................................................(Welding Engineering Standards HAZ............................................................................(Heat Affected Zone) PWHT.............................................................(Post Weld Heat Treatment) UT.................................................................................(Ultrasonic Testing) RT............................................................................(Radiographic Testing) PT.................................................................................(Penetrant Testing) VT............................................................................................(Visual Test) PRT..................................................................(Pressure Resistance Test) LT..............................................................................................(Leak Test) SNI................................................................(Standar Nasional Indonesia) WI.................................................................................(Welding Inspector) WE................................................................................(Welding Engineer) TEKNOLOGI LAS KAPAL D1DAFTAR GAMBAR BAB I I.1 Hubungan antara kandungan karbon dan sifat mekanis.........7 I.2 Diagram Proses Pembuatan Baja...........................................9 I.3 Percikan bunga api...............................................................12 I.4 Mistar baja lurus....................................................................18 I.5 Mistar siku.............................................................................18 I.6 Mistar gulung.........................................................................19 I.7 Calipers outside....................................................................19 I.8 Calipers inside.......................................................................19 I.9 Jangka sorong.......................................................................20 I.10 Micrometer dan pengukur standart.......................................20 I.11 Penunjuk ukuran dan tonggak penunjuk ukuran...................21 I.12 Tonggak magnet...................................................................21 I.13 Siku (mistar sudut kanan).....................................................21 I.14 Busur baja.............................................................................22 I.15 Busur bevel universal............................................................22 I.16 Pengukur jarak / celah..........................................................22 I.17 Pengukur sudut.....................................................................23 I.18 Pengukur jari – jari................................................................23 I.19 Pengukur lubang...................................................................23 I.20 Pengukur kerataan tipe segiempat........................................24 I.21 Meja penandaan permukaan plat..........................................24 I.22 Meja penyetelan permukaan plat..........................................24 I.23 Blok paralel...........................................................................25 I.24 Blok V....................................................................................25 I.25 Kotak blok V..........................................................................25 I.26 Pelat siku...............................................................................26 I.27 Alat penggores......................................................................26 I.28 Penyangga mistar.................................................................27 TEKNOLOGI LAS KAPAL D2I.29 Jangka biasa.........................................................................27 I.30 Jangka ulir.............................................................................27 I.31 Hermaphro-dite calipers........................................................28 I.32 Pena penandaan...................................................................28 I.33 Penitik...................................................................................28 I.34 Palu single.............................................................................29 I.35 Pahat datar............................................................................29 I.36 Pahat lancip..........................................................................29 I.37 Ragum...................................................................................30 I.38 Ragum paralel (Ragum horisontal).......................................30 I.39 Ragum kaki (ragum vertikal).................................................31 I.40 Ragum squill (klem C)...........................................................31 I.41 Bagian - bagian kikir..............................................................32 I.42 Bentuk – bentuk kikir.............................................................32 I.43 Gagang kikir..........................................................................32 I.44 Sikat kawat............................................................................33 I.45 Tap tangan............................................................................33 I.46 Pegangan tap........................................................................33 I.47 Tap luar ................................................................................34 I.48 Pegangan tap luar.................................................................34 I.49 Gergaji potong metal.............................................................35 I.50 Swage block..........................................................................35 I.51 Landasan jenis Perancis.......................................................35 I.52 Landasan jenis Inggris..........................................................35 I.53 Jenis tang tempa...................................................................36 I.54 Palu besar.............................................................................36 I.55 Pahat dengan gagang...........................................................37 I.56 Palu tempa............................................................................37 I.57 Gunting plat tipis...................................................................38 I.58 Pemotongan dengan gunting................................................38 I.59 Besi solder............................................................................38 TEKNOLOGI LAS KAPAL D3I.60 Jenis – jenis kunci.................................................................39 I.61 Obeng...................................................................................40 I.62 Tang potong..........................................................................40 I.63 Tang......................................................................................40 I.64 Tang catok............................................................................41 I.65 Kacamata pelindung debu....................................................41 I.66 Bor dengan mata bor miring..................................................41 I.67 Bor dengan mata bor lurus....................................................41 I.68 Cekam bor ............................................................................42 I.69 Sleeve / lengan penghubung................................................42 I.70 Soket.....................................................................................42 I.71 Drift / pasak...........................................................................43 I.72 Alat penyekat dengan air......................................................43 I.73 Regulator oksigen (tipe Jerman)...........................................44 I.74 Regulator oksigen (tipe Perancis).........................................44 I.75 Bagian regulator asetilin........................................................45 I.76 Tabung penyalur...................................................................45 I.77 Torch tekanan rendah...........................................................46 I.78 Brander potong dengan gas (jenis Perancis)........................47 I.79 Kacamata pelindung untuk las..............................................48 I.80 Korek / pematik.....................................................................48 I.81 Kap las tangan......................................................................49 I.82 Helm las................................................................................49 I.83 Sepatu keska........................................................................49 I.84 Selubung tangan las.............................................................49 I.85 Apron / pelindung dada.........................................................49 I.86 Sarung tangan.......................................................................49 I.87 Palu tetek..............................................................................50 I.88 Stang las untuk Las Busur Listrik..........................................50 I.89 Prinsip Pemotongan gas.......................................................52 TEKNOLOGI LAS KAPAL D4I.90 Pengaruh kemurnian oksigen pada kecepatan potong (Standar drag 0, tebal plat 50 mm) .......................................54 I.91 Efek perlakukan oksigen dari nyala preheating.....................56 I.92 Efek nyala preheating pada saat oksigen potong dinyalakan.............................................................................56 I.93 Faktor-faktor yang menentukan kualitas pemotongan permukaan............................................................................58 I.94 Pemotongan busur plasma...................................................59 I.95 Bentuk elektroda dan sistim suplai gas orifice......................62 I.96 Plasma injeksi air..................................................................63 I.97 Faktor-faktor yang menentukan kualitas permukaan potong busur plasma.........................................................................65 I.98 Sistim aliran ganda................................................................66 I.99 Kepala potong laser..............................................................67 I.100 Hubungan antara ketebalan plat dan kecepatan potong untuk baja lunak pada pemotongan sinar laser..............................68 I.101 Faktor-faktor yang mempengaruhi kualitas dari pemotongan sinar laser..............................................................................69 I.102 Alat potong gas manual........................................................70 I.103 Alat potong manual dan nama bagiannya.............................71 I.104 Nozzle potong.......................................................................72 I.105 Nama dan fungsi bagian-bagian brander pemotong.............72 I.106 Nyala api pemanasan awal...................................................74 I.107 Pemotongan manual.............................................................75 I.108 Pemeriksaan hasil pemotongan............................................76 I.109 Persiapan pemotongan dengan gas manual.........................77 I.110 Nyala busur api potong.........................................................77 I.111 Posisi material induk pada meja potong................................78 I.112 Pemotongan material............................................................78 I.113 Pengosongan tabung gas oksigen........................................79 I.114 Langkah pemotongan...........................................................79 I.115 Proses Pemotongan Otomatis dengan Gas..........................80 TEKNOLOGI LAS KAPAL D5I.116 Pemotongan lurus dengan alat pemotong otomatis..............84 I.117 Pengaturan arus gas oksigen...............................................85 I.118 Pengaturan posisi pucuk alat potong ke garis potong...........85 I.119 Gas oksigen menembus plat baja.........................................86 I.120 Pemotongan pinggiran miring...............................................88 I.121 Hubungan antara kondisi pemotongan dengan permukaan potong...................................................................................88 I.122 Ujung alat potong otomatis....................................................89 BAB II II.1 Contoh-contoh penyambungan mekanis.............................124 II.2 Penyambungan dengan pengelasan...................................125 II.3 Pengelasan plasma dengan bantalan serbuk.....................129 II.4 Perbedaan antara sambungan las dan sambungan tumpul yang dikeling.......................................................................130 II.5 Perbandingan distribusi tegangan antara sambungan keling dan las.................................................................................131 II.6 Deformasi dan deformasi sudut yang disebabkan oleh penyusutan..........................................................................134 II.7 Pengelasan tumpul plat.......................................................134 II.8 Distribusi tegangan sisa pada plat las tumpul.....................135 II.9 Perbandingan terjadinya retak pada sambungan keling.....136 II.10 Permukaan retak rapuh (Panah menunjukkan arah perambatan retak)...............................................................137 II.11 Aliran Tegangan Sambungan.............................................137 II.12 Pengaruh ketinggian pengisian las pada kekuatan fatik (lelah) dari las sambungan tumpul (baja lunak : 2 x 106 cycle)......138 II.13 Struktur busur dan distribusi tegangannya..........................140 II.14 Hubungan antara panjang busur dan tegangan busur........142 II.15 Karakteristik arus – tegangan pada busur...........................144 II.16 Busur DC.............................................................................144 II.17 Busur AC.............................................................................144 II.18 Efek Polaritas pada Las TIG...............................................146 TEKNOLOGI LAS KAPAL D6II.19 Las TIG AC.........................................................................147 II.20 Bentuk tip kawat las MIG....................................................148 II.21 Las MAG (100% CO2).........................................................148 II.22 Pembersihan (contoh pada aluminium (campuran)............148 II.23 Aliran gas............................................................................151 II.24 Las maju (turun), las mundur (naik)....................................151 II.25 Hembusan busur.................................................................152 II.26 Tiga jenis perpindahan butiran logam.................................153 II.27 Transfer sirkuit pendek dan perubahan arus.......................154 II.28 Kondisi terjadinya percikan pada las MAG (100% CO2).....155 II.29 Hubungan rasio campuran gas argon, CO2 dengan transfer butiran logam......................................................................156 II.30 Kemuluran Mn dan Si pada kawat las.................................157 II.31 Perubahan sifat mekanis dari logam las.............................157 II.32 Karakteristik eksternal dari mesin las busur........................158 II.33 Karakteristik menurun dan titik aksi busur...........................159 II.34 Titik gerak busur dari sumber daya tegangan konstan.......160 II.35 Mesin las busur AC tipe inti bergerak..................................163 II.36 Kontrol Thyristor..................................................................165 II.37 Kontrol inverter....................................................................165 II.38 Prinsip operasi dari alat penurun tegangan otomatis..........166 II.39 Tabel toleransi siklus kerja..................................................169 II.40 Pembumian yang benar dan pengkabelan sisi output........174 II.41 Contoh sisi pengkabelan output untuk dok galangan Kapal...................................................................................175 II.42 Pembumian dan pengkabelan sisi output yang buruk.........176 II.43 Kondisi kabel las dan penurunan tegangan........................176 II.44 Nama-nama dari bagian-bagian sambungan las................184 II.45 Pertumbuhan dendrit pada las lapis banyak.......................185 II.46 Struktur dan kekerasan maksimum dari daerah las ( SM 490 A ).......................................................................187 II.47 Konstruksi dari elektrode bersalut.......................................190 TEKNOLOGI LAS KAPAL D7II.48 Garis keterangan.................................................................226 II.49 Contoh perintah pengelasan dengan simbol.......................227 II.50 Sisi atas dan sisi bawah dari garis dasar............................227 II.51 Penunjukan dengan menggunaan garis penunjuk yang patah...................................................................................228 II.52 Sambungan las yang baik atau buruk berdasarkan bending momen................................................................................230 II.53 Sambungan las yang baik atau buruk berdasarkan konsentrasi garis las...........................................................230 II.54 Sambungan las tumpul antara dua logam yang berbeda ketebalan.............................................................................230 II.55 Sambungan las...................................................................231 II.56 Macam-macam las..............................................................231 II.57 Macam-macam las sudut....................................................232 II.58 Bentuk geometri kampuh....................................................232 II.59 Nama dari tiap-tiap bagian kampuh untuk sambungan tumpul.................................................................................232 II.60 Contoh-contoh penumpu las...............................................235 II.61 Daerah las ikat yang benar.................................................236 II.62 Diagram karakteristik sebagai jaminan kualitas pengelasan..........................................................................238 II.63 Macam-macam posisi pengelasan......................................242 II.64 Penyerapan kelembaban pada elektrode las......................242 II.65 Prosedur teknik menarik kembali awalan............................244 II.66 Macam-macam bentuk deformasi las.................................245 II.67 Metode pengaturan penyimpangan....................................246 II.68 Urutan pengerjaan..............................................................247 II.69 Macam-macam cacat las....................................................248 BAB III III.1 Mesin Las Busur Listrik.......................................................260 III.2 Sirkuit utama.......................................................................260 III.3 Sambungan kabel...............................................................261 TEKNOLOGI LAS KAPAL D8III.4 Pemasangan elektrode.......................................................261 III.5 Penyiapan tang ampere......................................................261 III.6 Pengaturan arus mesin las busur listrik..............................262 III.7 Pemeriksaan arus mesin las busur listrik............................262 III.8 Kaca pelindung mata..........................................................264 III.9 Pakaian pelindung kerja......................................................265 III.10 Peralatan kerja....................................................................265 III.11 Posisi tubuh saat penyalaan busur listrik............................266 III.12 Proses Penyalaan busur.....................................................267 III.13 Menghentikan busur............................................................267 III.14 Penyalaan busur pada pengelasan posisi datar.................268 III.15 Posisi elektrode...................................................................268 III.16 Posisi Batang Las...............................................................268 III.17 Posisi alur busur..................................................................269 III.18 Penampang sambungan las...............................................269 III.19 Cara pemutusan arus..........................................................269 III.20 Hasil pengelasan.................................................................270 III.21 Takik & overlap...................................................................270 III.22 Ayunan las saat pembuatan manik – manik posisi datar....271 III.23 Menyambung manik – manik las.........................................271 III.24 Menyalakan dan mematikan busur.....................................272 III.25 Poin pemeriksaan...............................................................272 III.26 Persiapan permukaan logam pengelasan tumpul posisi datar..........................................................................273 III.27 Las ikat pada pengelasan tumpul posisi datar....................273 III.28 Pembuatan busur................................................................274 III.29 Pengaturan las....................................................................274 III.30 Gerakan tangkai Las...........................................................274 III.31 Pemeriksaan hasil las.........................................................275 III.32 Persiapan awal pengelasan tumpul kampuh V posisi datar dengan penahan belakang..................................................275 III.33 Pemberian las ikat...............................................................276 TEKNOLOGI LAS KAPAL D9III.34 Pembuatan busur pada ujung lempeng penahan belakang..............................................................................276 III.35 Pengelasan pertama...........................................................277 III.36 Pengelasan kedua..............................................................277 III.37 Pengelasan ketiga...............................................................278 III.38 Pengelasan terakhir............................................................278 III.39 Proses pembukaan sudut...................................................279 III.40 Pemeriksaan las..................................................................279 III.41 Persiapan permukaan logam pada pengelasan sudut posisi horisontal.............................................................................280 III.42 Las ikat pada pengelasan sudut posisi horisontal...............280 III.43 Penyalaan busur.................................................................281 III.44 Mengelas sudut untuk alur tunggal.....................................281 III.45 Mengelas lajur kedua..........................................................282 III.46 Mengelas lajur ketiga..........................................................282 III.47 Contoh las T yang buruk.....................................................283 III.48 Persiapan permukaan las pada pengelasan vertikal rigi las lurus....................................................................................284 III.49 Posisi pengelasan saat pengelasan vertikal.......................284 III.50 Penyalaan busur.................................................................285 III.51 Pengelasan rigi – rigi...........................................................286 III.52 Pematian busur las.............................................................286 III.53 Pengisian kawah.................................................................286 III.54 Pemeriksaan hasil las.........................................................287 III.55 Penyalaan busur las pada pengelasan vertikal dengan ayunan................................................................................288 III.56 Pengelasan rigi – rigi...........................................................289 III.57 Pematian busur las.............................................................290 III.58 Pengisian kawah.................................................................290 III.59 Persiapan awal Pengelasan Sambungan Tumpul Kampuh V dengan Penguat Belakang..................................................291 III.60 Las ikat................................................................................292 III.61 Penyalaan busur.................................................................292 Next >