쉐도잉 연습: How Things Are Made | An Animated Introduction to Manufacturing Processes - 영상으로 영어 말하기 배우기

레슨 만드는 중...
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Do you ever wonder how amorphous lumps of material are turned into the everyday products which surround us?
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Let's find out.
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In this video, we're going to talk about manufacturing processes.
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There are six main categories of manufacturing processes, which are forming, casting, molding,
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joining, machining, and additive manufacturing.
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Each one of these categories contains a large number of different manufacturing techniques.
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There are a lot of different factors which need to be considered when selecting the right manufacturing process.
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This includes the material you are working with, the geometry of the object, the number of parts you are producing,
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tool and material costs, and required levels of automation to name just a few.
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Let's look through each of the six categories in detail.
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Forming involves applying forces or pressure and plastically deforming the material to produce the desired shape.
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It is typically used for metals.
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Most forming processes can be done when the metal is either above or below its recrystallization temperature.
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This is known as hot or cold working.
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Hot working makes it easier to plastically deform the metal, but cold working causes strain hardening, which increases the strength of the material.
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Three common forming processes are forging, rolling, and extrusion.
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Modern forging is done using machines.
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In closed die, or impression forging, the metal is placed between top and bottom closed dies.
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Repeated strokes from the hammer are used to cause the metal to flow into the shape of the dies.
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Objects produced using forging can have improved mechanical properties compared to objects which are cast,
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but it can be difficult to achieve tight tolerances using forging, and the required equipment can be expensive.
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Extrusion is a continuous process which involves placing hot metal in a chamber
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and using a ram to force it through a die, producing a long object with a constant cross -section.
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Extrusion provides an excellent surface finish and can achieve very tight tolerances, but it is only suitable for producing two -dimensional shapes.
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Rolling is probably the most commonly used forming process.
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Plus, it involves passing metal between two or more rollers, which apply pressure and reduce thickness.
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More complex products like I -beams can also be manufactured by rolling.
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Rolling can result in improved mechanical properties and can be automated, which makes it good for large -scale production
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but tooling costs tend to be high
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and it can't be used to produce very complex shapes let's move on to the next category of manufacturing processes casting
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casting involves pouring molten metal into a mold
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and allowing it to solidify it is what we call a
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primary shaping process a secondary process such as machining is typically needed to achieve the desired surface finish.
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Like forming, casting is most commonly used for metals.
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Three common types of casting are die casting, sand casting, and investment casting.
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In die casting, molten metal is forced into reusable metal dies at high pressure.
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Once the molten metal has solidified, it is removed from the mold.
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die casting is mostly used for non -ferrous metals like aluminum
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and zinc which have low melting temperatures it provides an excellent surface finish
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and can achieve very tight tolerances but startup costs tend to be high
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so it is only really suitable for large production runs
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in sand casting a pattern is used to create a single -use mold from damp sand
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the sand is typically contained in two mold boxes called the cope and the drag
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molten metal is poured into the mold through a channel formed in the sand When the metal has solidified, the cast object can be removed from the sand.
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Sand casting can be used for a wide range of metals, including those with high melting temperatures.
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It can produce large and complex parts, and initial costs are very low, making it good for small production runs.
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However, it provides a poor surface finish and is not as accurate as other casting processes.
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The last casting process we will look at is investment casting.
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Several wax patterns of the same object are created and attached to a sprue.
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The wax tree is dipped into a slurry to create a ceramic mold.
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Heat is applied to melt out the wax.
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Molten metal is then poured into the ceramic mold.
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once the casting has cooled the mold is broken off.
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Investment casting is good for parts with complex geometry and can achieve tight tolerances, but it is an expensive and time -consuming process.
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Molding is very similar to casting.
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It involves shaping a liquid or pliable material using a mold.
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Most of the time molding is used for forming plastics.
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Typical molding processes are injection molding, compression molding, and blow molding.
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Let's look at the first two.
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Injection molding is the most commonly used manufacturing method for plastics.
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Polymer granules are fed into the hopper
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and a screw is used to pass the material through a heated cylinder before it is forced at pressure into the mold.
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Injection molding is mostly used for thermoplastics, which are polymers which soften when they are heated and harden when they are cooled.
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It is a very fast process and can be fully automated, meaning labor costs are low.
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But startup costs are very high due to the expensive molds, so it is really only cost effective for large production runs.
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Compression molding involves placing a precise amount of material into a mold.
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The mold is closed and pressure and temperature are applied.
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Compression molding is mostly used for thermosets, which are polymers which irreversibly harden
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when heated tooling costs are relatively cheap making it good for small production runs
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but it is quite a slow process
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and is not well suited for complex designs
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so far we have only looked at material deformation processes machining
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is a material removal process where a tool is used to
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remove material from a larger object it is often used for secondary shaping
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when the part has already been formed using a primary process like casting.
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Machining can be used for a wide range of materials, including metals, plastics, and wood.
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Examples of machining include drilling, turning, and reaming.
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Drilling is the cutting of a normal circular hole by pressing a rotating drill bit through a solid object.
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and turning is the use of a cutting tool to shape a rotating workpiece.
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Let's move on to the next category.
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Joining involves combining multiple separate components into a larger assembly.
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Like machining, joining is a secondary process.
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Welding, riveting, brazing, soldering, and fastening are all different types of joining processes.
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Welding uses extremely high heat to fuse distinct metal parts together.
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Unlike soldering and brazing, the base metal melts during welding.
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The final category is additive manufacturing, which involves adding material to build up the desired object, typically one layer at a time.
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3D printing, selective laser sintering, and VAT polymerization are examples of additive manufacturing techniques.
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For 3D printing, a computer is used to successfully build up an object layer by layer.
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3D printing is a slow process, and the range of materials which can be used is limited.
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As a result, it tends to be used for prototyping rather than for mass production.
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That's it for this introduction to manufacturing processes.
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Please leave a comment to let me know what you think, and don't forget to subscribe if you haven't already.

이 레슨의 어휘와 말하기 포인트

이 C1 수준 말하기 레슨은 영상 “How Things Are Made”을(를) 바탕으로 합니다. 가장 자주 반복되는 단어는 다음과 같습니다: metal, casting, material, mold, process. 이 영상에는 섀도잉할 문장 92개와 단어 1229개가 있습니다. 말하는 구간의 길이는 10:17입니다. 화자는 분당 약 120단어의 일정한 속도로 말해서 섀도잉하기에 편한 속도입니다. 영어에서 가장 많이 쓰이는 3,000단어에 속하는 단어가 73%뿐이라 어휘가 어려운 편입니다.

이 영상의 핵심 어휘

영상에서 가장 어려운 단어 15개를 발음, 뜻과 함께 정리했습니다.

단어발음뜻
mold 명사/moʊld/곰팡이
melt 동사/mɛlt/녹다, 녹이다
forge 명사/fɔɹd͡ʒ/대장간
weld 동사/wɛld/용접하다
injection 명사/ɪnˈd͡ʒɛk.ʃən/주사
drill 명사/dɹɪl/드릴
automate 동사/ˈɔ.təˌmeɪt/자동화하다
solder 명사/ˈsɒl.də(ɹ)/땜납
ceramic 명사/səˈɹæmɪk/세라믹스, 세라믹
geometry 명사/d͡ʒiˈɑ.mə.tɹi/기하학
amorphous 형용사/əˈmɔ(ɹ)fəs/조직이 없는
grasshopper 명사/ˈɡɹæsˌhɑpəɹ/메뚜기
pliable 형용사/ˈplaɪəbəl/유연(柔軟)한
fuse 명사/fjuːz/도화선
damp 형용사/ˈdæmp/축축하다

이 영상의 문법

화자가 가장 많이 쓰는 문형을 영상 속 실제 표현과 함께 정리했습니다.

문형영상 속 표현
수동태 be + 과거분사 — 누가 하는지보다 무슨 일이 일어나는지에 초점are turned · be considered · can be done
관계절 who / which + 절 — 사람이나 사물에 대한 추가 정보processes, which are · objects which are · automated, which makes
현재완료 have/has + 과거분사 — 과거의 일이 지금도 관련이 있을 때have improved · has solidified · has cooled

주의할 발음

화자는 can't, don't, haven't 같은 축약형과 약화된 형태를 4번 사용합니다. 들리는 대로 짧게 발음하세요.

  • “sh”와 “zh” 소리: compression /kəmˈpɹɛʃ.ən/, injection /ɪnˈd͡ʒɛk.ʃən/, deformation /ˌdɛfəˈmeɪʃən/, polymerization /ˌpɒl.ɪ.məɹ.aɪˈzeɪ.ʃən/, automation /ˌɔ.təˈmeɪ.ʃən/
  • 긴 단어 — 강세 위치에 주의: solidify /səˈlɪdɪˌfaɪ/, geometry /d͡ʒiˈɑ.mə.tɹi/, deformation /ˌdɛfəˈmeɪʃən/, polymerization /ˌpɒl.ɪ.məɹ.aɪˈzeɪ.ʃən/, automation /ˌɔ.təˈmeɪ.ʃən/

한국어 화자가 어려워하는 소리:

  • /f/ — ㅍ(/p/)으로 바꾸지 말고 윗니를 아랫입술에 대기: forge /fɔɹd͡ʒ/, solidify /səˈlɪdɪˌfaɪ/, deform /dəˈfɔɹm/, amorphous /əˈmɔ(ɹ)fəs/, deformation /ˌdɛfəˈmeɪʃən/
  • /v/ — ㅂ(/b/)과 구별하기: additive /ˈæd.ɪ.tɪv/, selective /səˈlɛktɪv/
  • /z/ — ㅈ이 아니라 성대를 울리는 /s/: braze /bɹeɪz/, polymerization /ˌpɒl.ɪ.məɹ.aɪˈzeɪ.ʃən/, fuse /fjuːz/, zinc /ˈzɪŋk/

이 영상으로 연습하는 방법

  1. 먼저 말하지 않고 영상을 끝까지 듣고 모르는 단어를 적어 둡니다.
  2. 보통 속도로 한 문장씩 섀도잉하고, 화자의 리듬과 맞을 때까지 반복합니다.
  3. 자신의 목소리를 녹음해 원본과 비교하고, mold, melt, forge 같은 단어에 특히 주의합니다.

쉐도잉이란? 영어 실력을 빠르게 키우는 과학적 방법

쉐도잉(Shadowing)은 원래 전문 통역사 훈련을 위해 개발된 언어 학습 기법으로, 다언어 학자인 Dr. Alexander Arguelles에 의해 대중화된 방법입니다. 핵심 원리는 간단하지만 매우 강력합니다: 원어민의 영어를 들으면서 1~2초의 짧은 지연으로 즉시 소리 내어 따라 말하는 것——마치 '그림자(shadow)'처럼 화자를 따라가는 것입니다. 문법 공부나 수동적인 청취와 달리, 쉐도잉은 뇌와 입 근육이 동시에 실시간으로 영어를 처리하고 재현하도록 훈련합니다. 연구에 따르면 이 방법은 발음 정확도, 억양, 리듬, 연음, 청취력, 말하기 유창성을 크게 향상시킵니다. IELTS 스피킹 준비와 자연스러운 영어 소통을 원하는 분들에게 특히 효과적입니다.

섀도잉 방법: 단계별 전체 가이드 읽기 →