용접기술은 세계 최고 수준인 조선 산업에서 없어서는 안 될 중요한 국가기간 산업으로서 자리를 잡고 있습니다.
또한 금속재료의 다양화에 따라 기계, 금속, 건축, 토목, 우주 항공, 신재생에너지 분야에 있어서도 필수적인 기술이기도 합니다.
그로 인하여 용접기술을 담당하는 근로자 역시 산업분야에서 핵심적인 역할을 수행하게 되었습니다.

이책은 이러한 용접기능사 자격의 중요성을 염두에 두고 보다 전문적이고 체계화된 지식을 제공하기 위하여 다음 사항을 원칙으로 집필하게 되었습니다.

시행처인 한국 산업인력공단의 출제 기준에 따라 순서대로 구성하여 필기시험에 완벽하게 맞춘 핵심 내용을 정리하였습니다.

다양한 자료와 충실한 해설로 용접의 기본 원리부터 피복아크 용접기능사, 가스텅스텐 아크 용접기능사, 이산화탄소가스 아크용접기능사까지 한 번에 준비하도록 하였습니다.

20년 이상 용접 기술 분야에 종사하면서 수집하고 분류한 자료를 최대한 효율적으로 정리한 결과입니다. 이를 통해 원하는 용접관련 자격증을 수험생들이 보다 손쉽게 취득 할 수 있도록 돕고자 합니다.

◎ 책 특징

-  주요내용 강조 및 출제빈도 높은 이론 분석-  기출문제 분석정리-  자주 나오는 계산문제
-  마지막 30분 정리하기-  실기 Tip. 기본 전류값 한 눈에 파악하기 

01. 이론
PART 01 용접일반
Chapter 01. 용접의 원리 ································································································ 46
 01. 용접의 개요 ··································································································· 46
 02. 용접의 장ㆍ단점 및 역사 ··············································································· 47
 Chapter 02. 피복 아크 용접 ····························································································49
 01. 피복 아크 용접의 원리 ·················································································· 49
02. 피복 아크 용접의 전압 분포 ········································································· 51
 03. 극성 ················································································································· 52
 04. 아크 쏠림 ········································································································ 53
 05. 용접 입열 ········································································································ 54
 06. 용융 금속의 3가지 이행 형식 ······································································· 55
 07. 교류 아크 용접기 ··························································································· 56
 08. 용접기의 사용율 및 역률과 효율 ·································································· 58
 09. 직류 용접기 ···································································································· 59
 10. 용접기의 특성 ································································································· 60
 11. 피복아크용접기 ····························································································· 61
 12. 용접 작업용 기구 및 보호구 ········································································· 62
 13. 피복 아크 용접의 피복제 ··············································································· 63
 14. 용접봉의 규격 ································································································· 64
 15. 피복 아크 용접 작업 ······················································································ 67
 16. 용접 결함 ········································································································ 69
 Chapter 03. 전기 저항 용접 ····························································································72
 01. 전기 저항 용접의 개요 ·················································································· 72
 02. 전기 저항 용접의 종류 ·················································································· 73
 Chapter 04. 가스용접 및 절단 ························································································78
 01. 가스 용접의 개요 ··························································································· 78
 02. 용접용 가스 ···································································································· 80
 03. 아세틸렌 발생기 ····························································································· 83
 04. 아세틸렌의 폭발성 ························································································ 85
 05. 용해 아세틸렌 ································································································· 86
 06. 산소 용기와 호스 ··························································································· 87
 07. 산소 아세틸렌의 불꽃의 종류 ········································································ 89
 08. 역류, 역화 및 인화 ························································································ 90
 09. 용접용 재료 및 용제 ······················································································ 90
 10. 토치 및 팁 ······································································································ 93
 11. 부속장치 ·········································································································· 94
 12. 보호구 및 공구 ······························································································· 95
 13. 산소 - 아세틸렌 용접 작업 ············································································· 96
 14. 절단 ················································································································· 97
 15. 납땜법 ··········································································································· 105
 Chapter 05. 특수용접 ····································································································109
 01. 불활성 가스 아크 용접(GTAW, GMAW-MIG, MAG,CO2) ·························· 109
 02. 서브머지드 아크 용접(잠호 용접) ································································ 114
 03. 이산화탄소 아크 용접 ·················································································· 117
 04. 논실드 아크 용접 ························································································· 121
 05. 플라즈마 아크 용접 ······················································································ 122
 06. 일랙트로 슬랙 용접 ······················································································ 124
 07. 일랙트로 가스 용접(인클로오스 탄산가스 용접) ········································· 125
 08. 전자 빔 용접 ································································································ 125
 09. 테르밋 용접 ·································································································· 126
 10. 원자 수소 용접 ····························································································· 127
 11. 아크 점 용접법 ····························································································· 128
 12. 초음파 용접 ·································································································· 128
 13. 가스 압접 ······································································································ 129
 14. 마찰 용접 ······································································································ 129
 15. 단락 이행 용접(short arc welding) ··························································· 129
 16. 플라스틱 용접 ······························································································· 130
 17. 스터드 용접 ·································································································· 130
 18. 레이저 빔 용접 ····························································································· 131
 19. 고주파 용접 ·································································································· 131
 20. 아크 이미지 용접 ························································································· 131
 21. 로봇 용접 ······································································································ 131
 Chapter 06. 각종 금속의 용접 ······················································································133
 01. 고탄소강 ········································································································ 133
 02. 주철 ··············································································································· 134
 03. 스테인리스강 ································································································· 135
 04. 구리 및 구리 합금 ······················································································· 136
 05. 알루미늄 합금 ······························································································· 136
 PART 02 용접시공 및 검사
Chapter 01. 용접시공 ····································································································140
 01. 용접 준비 ······································································································ 140
 02. 용접작업 ········································································································ 141
 03. 용접 후 처리 ································································································ 144
 Chapter 02. 용접설계 ····································································································148
 01. 용접자가 갖추어야할 지식 ··········································································· 148
 02. 용접이음의 종류 ··························································································· 148
 03. 용접 흠 형상의 종류 ···················································································· 149
 04. 용착부 모양에 따른 분류 ············································································· 149
 05. 용접홈의 명칭 ······························································································· 150
 06. 필렛 용접의 종류 ························································································· 150
 07. 용접이음의 강도 ··························································································· 150
 08. 용접이음 설계를 할 때 주의점 ···································································· 151
 Chapter 03. 용접부의 시험 및 검사 ·············································································152
 01. 용접부의 시험 및 검사 ················································································ 152
 Chapter 04. 작업안전 ····································································································160
 01. 안전 표식의 색채 ························································································· 160
 02. 작업 환경 ······································································································ 160
 03. 통행과 운반 ·································································································· 161
 04. 화재 및 폭발 방지책 ···················································································· 161
 05. 소화기 ··········································································································· 162
 06. 전기 용접 작업의 장애 ················································································ 162
 PART 03 용접의 재료
Chapter 01. 금속의 개요 ·······························································································166
 01. 금속과 그 합금 ····························································································· 166
 02. 재료의 성질 ·································································································· 167
 03. 금속의 결정 ·································································································· 169
 04. 합금의 조직 ·································································································· 172
 Chapter 02. 철강재료 ····································································································174
 01. 제철법 ··········································································································· 174
 02. 탄소강 ··········································································································· 177
 03. 특수강 ··········································································································· 182
 04. 주철 ··············································································································· 187
 Chapter 03. 열처리 ········································································································193
 01. 일반 열처리 ·································································································· 193
 02. 특수 열처리 ·································································································· 196
 Chapter 04. 비철 금속과 그 합금 ················································································199
 01. 구리와 그 합금 ····························································································· 199
 02. 알루미늄과 그 합금 ······················································································ 203
 03. 마그네슘과 그 합금 ······················································································ 205
 04. 기타 비철 금속 ····························································································· 206
 PART 04 기계제도
Chapter 01. 제도통칙 ····································································································210
 01. 제도(Drawing)의 정의 ················································································ 210
 02. 제도 용구 ······································································································ 212
 03. 선과 문자 ······································································································ 212
 04. 기본 도법 ······································································································ 214
 05. 단면의 표시법 ······························································································· 217
 06. 치수 표시법 ·································································································· 219
 07. 치수 공차 ······································································································ 222
 08. 표면 거칠기와 다듬질 기호 ········································································· 223
 09. 재료 기호 ······································································································ 224
 10. 체결용 기계 요소 ························································································· 225
 11. 스케치도 작성법 ··························································································· 228
 Chapter 02. KS도시기호 ································································································230
 01. 용접 기호 및 도면의 해독 ··········································································· 230
 02. 배관의 도시기호 ··························································································· 233
 03. 판금ㆍ제관 및 철골 구조물 해독 ································································· 235
 04. 용접 기호 ···································································································· 236
 02. 문제
 문 제 연도별 기출문제
2015년 1회｜용접기능사 기출문제 ············································································ 242
 2015년 1회｜특수용접기능사 기출문제 ····································································· 256
 2015년 2회｜용접기능사 기출문제 ············································································ 268
 2015년 2회｜특수용접기능사 기출문제 ····································································· 282
 2015년 4회｜용접기능사 기출문제 ············································································ 296
 2015년 4회｜특수용접기능사 기출문제 ····································································· 309
 2016년 1회｜용접기능사 기출문제 ············································································ 321
 2016년 1회｜특수용접기능사 기출문제 ····································································· 333
 2016년 2회｜용접기능사 기출문제 ············································································ 345
 2016년 2회｜특수용접기능사 기출문제 ····································································· 357
 2016년 4회｜용접기능사 기출문제 ············································································ 370
 2016년 4회｜특수용접기능사 기출문제 ····································································· 383
 2017년｜용접기능사 기출문제 ···················································································· 396
 2017년｜특수용접기능사 기출문제 ············································································· 409
 2018년｜용접기능사 기출문제 ···················································································· 422
 2018년｜특수용접기능사 기출문제 ············································································· 435
 2019년｜용접기능사 기출문제 ···················································································· 448
 2019년｜특수용접기능사 기출문제 ············································································· 461
 2020년｜용접기능사 기출문제 ···················································································· 475
 2020년｜특수용접기능사 기출문제 ············································································· 487
 03. 부록
01. 자주 나오는 계산문제 확실히 정리하기 ······························································ 502
 02. 마지막 30분 정리하기 ························································································· 512
 03. 실기시험 기본 전류값 ·························································································· 542