跟讀練習: WELDING DEFECTS!! Porosity, Arc Strikes, Undercut - 通過影片學習英語口語

選擇練習模式

每種模式都會開啟全屏練習室。

139 句

如果句子過短或過長，請點選 Edit 進行調整。

Hola, buenos dias.

Bienvenidos para weld .com.

Oh, wait, sorry.

Hey guys, welcome back to another episode of weld .com.

Today we're gonna talk about discontinuities.

So it's gonna be the first video of a series

and we're just gonna go through and take you step by step and we're gonna address different weld discontinuities, how to avoid them, what they are,

common mistakes involved with them.

Note that a welding discontinuity does not automatically call for a rejection okay

so while all defects are discontinuities not all discontinuities are well defects

so depending on

which code book you're working with you are a lot of a certain amount of undercut per linear inch

you're allowed a certain amount of porosity per diameter and linear inch

so there's just different things and it all depends on

which code you're working with i don't want to get into the specifics of it

because if i say one thing somebody's going to say well that's not how it is in my code

and this is just a general weld discontinuities how to identify them

and then how to avoid them in the future

so we're going to go ahead

and get right into it probably the most we're going to address the three most common today

which is undercut porosity and arc strikes

so we're going to start there they're pretty basic we're going to show you how to avoid them

and what exactly what they are okay

so the first one we're going to talk about is undercut

so undercuts pretty common what that is it's an eroded edge along the toe of one

if not both of the toes of the weld so essentially what

that does is

if i have undercut on both sides of this material this material is 3 8 thick

and i have a 16th undercut on each side i've basically deducted a 16th from the thickness of this material

so i have that's roughly uh 6 16ths

now i'm down to 516 thickness the plate is no longer 3 8 of an inch thick don't know what

that is a metric for you folks across the pond

I do apologize camera guys got

you covered he's gonna put some notes here maybe here somewhere

he'll put some notes in what can cause undercut is improper travel speed

so if I travel down this joint too fast I can get undercut

and that's because I'm not giving that rod or that electrode time to fill in another thing is poor work angle.

Ideally, what I want to have is half of my weld on the vertical part of this plate

and half of it on the horizontal part of this plate.

Now, I want to maintain an even angle between the two, so 45 is roughly where I want to be.

If I start getting too far one way or the other, I'm bound to get undercut.

I'm going to show you that here in a second.

If I have a travel angle, or I'm sorry, a work angle that's too high, I'm going to get undercut along this top edge.

So another thing that can cause undercut is if my arc length is too long.

So ideally I want to keep my arc length no more than the diameter of this electrode.

So if I have eighth inch electrode, I don't want to be any more than an eighth inch off the edge of that puddle.

I like to stay close to the puddle.

That's just me personally.

It's just a habit I've developed, but you don't want to go any further than one eighth.

You start getting outside of that area, you're going to start getting undercut.

You have to think as I pull this rod further away from this plate, my voltage is going to increase.

Okay, this is a constant current process.

Stick welding is a constant current process.

If I pull back far enough, the voltage becomes my variable.

Okay, it'll increase when I pull back too far.

It'll decrease when I get in too close.

Because that additional voltage, it's going to start cutting away in the sides and it's not going to fill in properly.

So we'll go ahead and we'll put all those together and we'll see if we can whip you up some undercut.

So as you can see the work angle that I have here is improper.

It's way too high.

It's a lot higher than what I need.

If you want to bring this down you can bring it down to about a 45 degree angle

and that should be about where you want it.

This weld we're doing everything wrong.

Okay travel speed is too high, work angle is incorrect, amperage is set up you know a little bit above normal just

so I can produce that undercut so I can show those that don't know exactly what it is what to look for.

But because the angle, the speed, I ended up with that undercut on that top edge, which is where I wanted it.

You know, if I was welding vertical, you know, you could get undercut on the left

or the right -hand side just because you're not spending enough time on the sides.

But here, it's going to be more prevalent on the vertical piece

or the top leg or the top toe of that weld that you're going to put in there.

Another thing you see in here because that excessive arc length

when I pulled back is I had excessive spatter on the workpiece as well

so that's just kind of like molten metal that's that's popping off

or because the puddle's too hot you know it's kind of bouncing out there's too much energy in there

and this stuff's going to spray all over the place.

You want to get rid of that also you don't want to leave

that on your plates especially if you know you're getting and weld inspections, you know, the inspectors are gonna look for that.

Go ahead, take your time, clean up your plate.

Next thing we're gonna talk about is arc strikes.

So arc strikes happen for mainly one reason.

and possibly two arc strikes are typically caused due to carelessness recklessness

you're not paying attention accidentally touch the work piece you know with a live electrode

and you scrape down there it's discontinuity

you want to avoid arc strikes in your weld material

they can cause micro cracks outside of the welding area especially

if on a building or a structure that's cyclically loaded

that little micro structure those little cracks in there they can start propagating through the weld metal or the base metal.

So you don't want arc strikes on your material.

It's going to be up to the inspector whether he's going to have you cut that piece out,

remove it, repair it, whatever the case may be.

So you want to avoid arc strikes.

The biggest thing that I see that causes arc strikes, like I said, is carelessness.

But when students are first, well, students and experienced welders, when they strike the arc and they get stuck,

they want to fight the rod back and forth

and just kind of pop it off

there you know versus just disconnecting the stinger letting the electrode sit there for a second cool off

and then snap it what happens is once this becomes stuck

and I start moving back and forth I don't know

100

when it's gonna break free this thing breaks free

101

and then I get arc strike all the way across my plate way outside of my welding zone

102

that's what you want to try to avoid all right next we're going to talk about piracy

103

or tiny little weld bubbles that are in your weld what can cause porosity is

104

if you're welding and it is too windy outside so

105

if you're using a gas metal arc welding process outside

106

and it's too windy

107

you can get porosity using flux core outside up to a certain amount of miles per hour of the wind

108

you can get porosity that way

109

if you're not using the appropriate cubic feet per hour of shielding gas for gas metal arc welding process

110

you can get porosity hydrocarbons such as wd -40 or paint or anything like that that is on the base material

111

If you don't clean that off, that can cause porosity as well.

112

So we're going to go ahead and get into it and show you exactly what porosity looks like.

113

So we're welding along normal.

114

Now Man Cub's going to hit the weld zone with a

115

little bit of compressed air to simulate a big gust of wind coming through or welding outside.

116

So as you can see, everything's pretty unruly.

117

No gas coverage, getting porosity, trailing the weld.

118

It's not a good condition.

119

Very blustery day under here.

120

All right guys, so that's pretty much porosity in a nutshell.

121

You can get porosity with pretty much any welding process that you do.

122

It's all about gas coverage and shielding that weld pool, keeping everything nice and clean in that area, taking off any mill scale,

123

dirt, debris, hydrocarbons, oils, solvents, anything like that.

124

Fluxicore arc welding is also prone to wormhole porosity,

125

so that's a different type of porosity you typically don't get with shielded metal arc welding or gas metal arc welding.

126

Go ahead and check out our previous video, How to Avoid Wormholes, if that's something you're experiencing.

127

That pretty much concludes this episode.

128

Like I said, it's the first of a series.

129

So I hope you guys learned something.

130

Make sure you like and subscribe to the channel.

131

132

Make sure you hit that little bell button down here.

133

You'll get new notifications every Monday, Wednesday, and Friday at 5 .30 Eastern Standard Time when we release new videos.

134

And until next time, make every weld better than your last.

135

Take three. And action.

136

What the .

137

Did you guys see that?

138

That's what I got to put up with.

139

Hello again.

下載應用

流利口語所需的一切

AI 發音評分逐句打分

音標練習掌握每個音

詞彙學習建立你的詞庫

詞彙遊戲邊玩邊學

掃碼

Download on theApp Store Get it onGoogle Play

同頻道

WELDING DEFECTS!! Part 2

Daily ConversationUniversity Students

FOR YOU

本課的詞彙與口語要點

這節口語課以影片“WELDING DEFECTS!! Porosity, Arc Strikes, Undercut”為素材。影片中反覆出現的詞有：arc, weld, undercut, welding, porosity。這段影片共有 139 個句子、1686 個單詞可供跟讀。講話部分時長為 8:29。說話人語速較快，每分鐘約 199 個詞，會出現較多連讀和弱讀。只有 81% 的單詞屬於英語最常用的 3,000 詞，詞彙難度較高。

影片中的重點詞彙

影片中 15 個值得學習的單詞，附發音和釋義：

單詞	發音	釋義
angle 名詞	/ˈæŋ.ɡəl/	角, 角度
shield 名詞	/ˈʃild/	盾, 盾牌
eighth 形容詞	/eɪtθ/	第八
vertical 形容詞	/ˈvɝ.tɪ.kəl/	豎的 /豎的, 垂直
voltage 名詞	/ˈvəʊltɪd͡ʒ/	電壓 /電壓
thick 形容詞	/θɪk/	ху, 厚
crack 名詞	/kɹæk/	裂縫 /裂縫, 裂紋 /裂紋
inspector 名詞	/ɪnˈspɛk.tɚ/	檢查員 /檢查員, 檢驗員 /檢驗員
depend 動詞	/dɪˈpɛnd/	信任, 信賴 /信賴
excessive 形容詞	/ɪkˈsɛsɪv/	過度 /過度, 過分 /過分
linear 形容詞	/ˈlɪn.i.əɹ/	線性
diameter 名詞	/daɪˈæmɪdɚ/	直徑 /直徑
microwave 名詞	/ˈmaɪkɹoʊˌweɪv/	微波
thickness 名詞	/ˈθɪknəs/	厚度
defect 名詞	/ˈdiːfɛkt/	缺點 /缺點, 問題 /問題

影片中出現的短語動詞

單詞	發音	釋義
go ahead 動詞	/ˌɡoʊ əˈhɛd/	請便 /請便
check out 動詞		退房
go through 動詞		通過 /通過
take off 動詞		脫 /脫

值得反覆跟讀的句子

影片中簡短而完整的句子，可以直接用在日常對話裡：

Today we're gonna talk about discontinuities.
It'll decrease when I get in too close.
It's a lot higher than what I need.
This weld we're doing everything wrong.
Did you guys see that?

需要注意的發音

說話人用了 59 次縮略和弱讀形式，例如 we're, you're, don't。請按聽到的簡短形式來說。

“th” 音: eighth /eɪtθ/, thick /θɪk/, thickness /ˈθɪknəs/
“sh” 和 “zh” 音: shield /ˈʃild/, essentially /ɪˈsɛnʃəli/, inspection /ɪnˈspɛkʃən/, notification /ˌnoʊtɪfɪˈkeɪʃn̩/, rejection /ɹɪˈd͡ʒɛkʃən/
長單詞——注意重音位置: diameter /daɪˈæmɪdɚ/, ideally /aɪˈdi.ə.li/, essentially /ɪˈsɛnʃəli/, accidentally /ˌæk.sɪˈdɛnt(ə)li/, apologize /əˈpɑləˌd͡ʒaɪz/

中文母語者容易讀錯的音：

/v/ — 不要讀成 /w/，上齒輕觸下唇: vertical /ˈvɝ.tɪ.kəl/, voltage /ˈvəʊltɪd͡ʒ/, excessive /ɪkˈsɛsɪv/, microwave /ˈmaɪkɹoʊˌweɪv/, versus /ˈvɝsəs/
詞尾子音 — 要讀清楚，後面不要加母音: shield /ˈʃild/, eighth /eɪtθ/, voltage /ˈvəʊltɪd͡ʒ/, thick /θɪk/, crack /kɹæk/
/r/ 和 /l/ 的區別: roughly /ˈɹʌf.li/, linear /ˈlɪn.i.əɹ/, trail /tɹeɪl/, variable [ˈvæɹ.i.ə.bl̩], horizontal /ˌhoɹəˈzɑn.təl/

如何用這段影片練習

先完整聽一遍影片，不要開口，記下不認識的單詞。
先用 0.75 倍速逐句跟讀，熟練之後再回到正常速度。
錄下自己的聲音並與原聲對比，特別注意 angle, shield, eighth 這類單詞。

什麼是跟讀法？

跟讀法 (Shadowing) 是一種有科學依據的語言學習技巧，最初開發用於專業口譯員的培訓，並由多語言者Alexander Arguelles博士普及。這個方法簡單而強大：您在聽英語母語原聲的同時立即大聲重複——就像是一個延遲1-2秒緊跟說話者的影子。與被動聽力或語法練習不同，跟讀法強迫您的大腦和口腔肌肉同時處理並模模擬實的講話模式。研究表明它能顯著提高發音準確性，語調，節奏，連讀，聽力理解和口語流利度——使其成為雅思口語備考和真實英語交流最有效的方法之一。

影子跟讀法: 閱讀完整分步指南 →

跟讀練習: WELDING DEFECTS!! Porosity, Arc Strikes, Undercut - 通過影片學習英語口語

選擇練習模式

下載應用

同頻道

WELDING DEFECTS!! Part 2

推薦影片

OWASP Top 10 Explained

Handy CSS layout patterns, and fun ways to elevate them

Diodes Explained - The basics how diodes work working principle pn junction

The 7 Quality Control (QC) Tools Explained with an Example!

What is IMC (Intermetallic Compounds) part III? Explain Alloy, Eutectic in detail

Database Sharding! Designing Data-Intensive Applications chapter 6

The Anatomy of Fraud

什麼是屏蔽罩(shielding can)？工程師對屏蔽罩的愛恨情仇

What is Docker? Docker container concept explained || Docker Tutorial 1

Architectural Design Process Explained

Other Corneal Disorders - CRASH! Medical Review Series