석유화학공업의 발전과 함께 다양한 종류의 플라스틱 수지가 끊임없이 개발되어 플라스틱 제품의 비중이 날로 커지고 있다. 플라스틱 제품을 대량 생산하기 위해서는 사출금형이 필요하고 이를 위해서 금형을 제작하고 설계하는 능력이 뒷받침 되어야 한다. 금형 기술은 제품의 품질과 직결되기 때문에 완성품의 경쟁력을 높이기 위해서는 우수한 금형 기술자 양성이 필수적이다.

제품이 크고 복잡하거나 정밀을 요할수록 금형 제작 비용이 높아지기 때문에 최근에는 3D프린터로 시제품을 만들어서 사전에 충분한 기능 테스트를 거치는 추세이다. 제품설계,3D프린터, 금형설계 등에 있어서 가장 핵심 기술이 3차원 CAD 능력이다. 3차원 설계에 대한 교육은 2000년대에 들어와서 본격적으로 교육과정에 도입되기 시작하였는데, 금형 분야에서는 한국금형공업협동조합이 “전국 대학생 금형 3차원 CAD기술경진대회”를 2004년부터 매년 개최하면서 대학에서 이에 대비한 교육환경을 구축하고 전문 기술 인재를 양성해오고 있다.

3차원 설계를 위한 소프트웨어에는 UG(Unigraphics)를 비롯하여 CATIA, CREO, Inventor 등 여러 종류가 있는데, 본 기술서적을 저술한 목적은 금형 관련 분야에서 가장 활용도가 높은 UG를 이용해서 학생들 또는 현장 초심자가 스스로 학습하여 기량을 높일 수 있는 교재를 만들고자 함이다.

책의 구성을 살펴보면, 간단한 제품에 대한 설계(1장)가 먼저 나오고 금형설계를 위한 제품 데이터 수정(2장)과 함께 Layout 설계(3장), Core/Cavity 설계(4장), 유동 기구 설계(5장) 등 성형부에 대한 3차원 설계 방법을 제시한다.

이어서 몰드 베이스 설계(6장), 밀핀 및 냉각회로 설계(7장), 표준 부품 설계(8장) 등의 순으로 사출금형 3차원 설계 전 과정이 Bottom-up 방식으로 진행된다. 조립(9장) 부분에서 개별 부품으로 내보내기, 조립하기, 간섭 체크 등을 통해서 부품 간에 문제가 발생하는 부분을 해결하며, 금형이 열리고 제품 취출 후 다시 금형이 닫히는 과정을 구속조건, 이동, 배치 등의 기능을 이용해서 구현할 수 있도록 하였다. 마지막 부분에 PMI 및 Drafting(10장)을 통해서 3차원에서 주요 치수를 비롯한 제품 정보를 표기하는 방법과 함께 이를 2차원 도면으로 나타내는 것을 끝으로 마무리하였다.

각 장별로 3차원 설계에 필요한 개념과 부품 규격 등을 소개하고 전체 과정을 따라하기 식으로 구성하면서 독자 스스로 UG의 다양한 기능을 최대한 이용함으로써 활용 능력을 높일 수 있도록 하였다. 사출금형 설계를 공부하는 학생뿐만 아니라 금형 관련 업무에 종사하는 산업계 초년생을 비롯해서 제품설계, 3D프린터 등에 관심이 있는 많은 사람들에게 도움을 줄 것으로 기대한다.

향후 전문가들뿐만 아니라 독자들의 의견에도 귀를 기울여서 보완할 부분이 있으면 개선하도록 노력하겠다. 그리고 현장 전문가에게 도움을 줄 수 있는 “사출금형 3차원 CAD(중급)”의 저술로 이어질 수 있도록 독자 여러분들의 많은 성원과 지도편달을 바란다.

Ⅰ 제품 설계

1. 제품 검토 ··································································································· 1

2. 제품 모델링 ································································································ 2

Ⅱ 데이터 준비

1. 사출금형 설계를 위한 제품 검토 ···························································· 17

2. 데이터 수정 ······························································································ 19

Ⅲ Layout 설계

1. Layout ······································································································ 27

2. 스프루 부시 스케치 ·················································································· 31

3. 게이트 스케치 ·························································································· 33

4. 런너 스케치 ······························································································ 38

Ⅳ Core 및 Cavity 설계

1. 가동측 인서트 코어 설계 ········································································· 45

2. 고정측 인서트 코어 및 코어 핀 설계 ····················································· 56 

Ⅴ 유동 기구의 설계

1. 몰드 베이스 선정 ····················································································· 77

2. 스프루 부시의 설계 ·················································································· 81

3. 스프루의 설계 ·························································································· 88

4. 런너의 설계 ······························································································ 90

5. 게이트의 설계 ·························································································· 93

Ⅵ Mold Base 설계

1. 몰드 베이스의 세부 치수 ········································································· 97

2. 고정측 형판의 설계 ··············································································· 101

3. 가동측 형판의 설계 ··············································································· 106

4. 고정측 설치판의 설계 ············································································ 107

5. 스페이서 블록의 설계 ············································································ 108

6. 가동측 설치판의 설계 ············································································ 110

7. 밀판(이젝터 플레이트)의 설계 ······························································· 112

Ⅶ 밀핀 및 냉각회로 설계

1. 스톱 핀의 설계 ······················································································ 115

2. 취출 시스템의 설계 ··············································································· 128

3. 고정측 냉각수 채널의 설계 ··································································· 140

4. 고정측 오링(O Ring)의 설계 ································································· 154

5. 가동측 냉각수 채널의 설계 ··································································· 159

6. 가동측 오링(O Ring)의 설계 ································································· 166 

Ⅷ 표준 부품 설계

1. 스프루 록 핀의 설계 ·············································································· 169

2. 리턴 핀의 설계 ······················································································ 180

3. 가이드 핀의 설계 ··················································································· 191

4. 가이드 부시의 설계 ··············································································· 204

5. 로케이트 링의 설계 ··············································································· 214

6. 육각 구멍붙이 볼트의 설계 ··································································· 222

7. 스프링의 설계 ························································································ 258

8. 기타 설계 ······························································································· 271

Ⅸ Assembly(조립)

1. Assembly 개요 ························································································281

2. 파트 내보내기 ··························································································282

3. 사출금형 Assembly(조립) ········································································289

4. 간섭 체크(Clearance Check) ··································································310

5. 이동(Move) 및 배치(Arrangement) ·························································329

Ⅹ PMI 및 Drafting(제도)

1. PMI의 개요 ····························································································· 345

2. 제품의 PMI 및 Drafting ········································································· 346

3. 조립도 Drafting ······················································································ 368

4. 사출금형 부품의 PMI ············································································· 392

￭참고문헌 ··············································································································· 399