中质盟基础英语培训——课文Unit 2。

Lesson 3

Part 1 Terminal crimping 端子压接

Word Service Station 词语加油站

Sequence ['sikwəns] n.顺序 ｜ Crimp [krimp] v. 压接

Shielding [‘ʃilding] n. 屏蔽 ｜ diagonal pliers [daɪ'æɡənəl] n. 斜口钳

Backward ['bækwərd] adv. 向后 ｜ terminal ['tɜrminəl] n. 端子
 

Article: Terminal crimping 端子压接

Process Step: Cable cutting(断线), Preparing cable end (端部处理), Crimping power wire (压接电源线), Crimping and checking the signal wire (压接并检查信号线)

There are 3 process steps before signal wire crimping: they are the cable cutting, Preparing cable ends and Crimping power wire.

Process Step 1:
In the cable cutting, the operating sequence（操作顺序） is checking the type of raw cable, and broken, scratch and contamination on the jacket in unqualified (护套上的破损、划伤及脏污不可接受） and scrapping the first and last 1 meter in every drum. Choose the right cable cutting specification (断线标准）, on the basis of the production order and relevant drawings (基于生产订单和相关图纸）.

Process Step 2:
In the preparing cable ends, strip the cable ends (剥去电缆端部）, remove the jacket and fillings (除去护套和填充物), push the cable shielding wires backward (向后翻电缆屏蔽), cut shielding wire and wrap the copper foil around shielding wire as below (如下图用铜箔包裹屏蔽丝）.

Push the plastic foil backward (向后翻塑料薄膜), remove the filling yarn, and fit the shrink tube(套上热缩套管). Remove the transparent foil with diagonal pliers (用斜口钳剪去透明薄膜), cut the aluminum foil (铝箔) into 10~15mm. Push aluminum foil and grounding wire backward (向后翻铝箔和地线). Cut the signal wire into 30mm.

Process Step 3:
Strip the power wire on the machine US 2300(用机器US2300来剥电源线), strip the cable insulation from the end of the power wire (从电源线根部开始剥电缆绝缘), and bend and fit the grounding wire between the power wires (弯曲并将地线塞入电源线之间). Wrap the power red & white wires with tape, and wrap the green, black and grounding wires with tape respectively (分别用胶带包裹红/白电源线，绿/黑电源线/地线).

Crimp terminal for Power wires and check the grounding wires, and then remove the tape after crimping terminal.

Process Step 4:
Strip the signal wire and crimp the signal terminal on machine SC200. Check the signal terminal with magnifier (用放大镜检查信号线).
 

Part 2 PCBA soldering 介绍PCBA焊接

注意，Part 2的英文表述并不恰当，在课堂上练习纠错用。

 
attention for the correct stamp size
选择正确的焊接头

attention for the correct solder program
选择正确的焊接程序

place two PCB’s into the PCB holder
在PCB 支撑架中装入2 个PCB

place the PCB holder into the jig
将PCB 支撑架装在夹具底座上

push the pairs down to the PCB using the helping tool
用压线工装将芯线压向PCB

put the jig into the machine
将夹具放入机器中

adjust the wires onto the solder pads using the tweezers
使用镊子将芯线导体调整在焊脚中间

Protruding wires have to be cutted carefully by using a side cutter.
超出的导体用斜口钳小心的剪掉

Part 3 Soldering parameters 焊接参数

 
Temperatures: Setting the temperatures for the pre-heating and heating phase 温度：设置预热温度和加热温度阶段

Pre-heating temperature: 预热温度
This is where a temperature, which should be reached before the actual heating temperature (这是一个在达到实际温度之前的温度) (see chart below, yellow chart), can be set for the soldering iron.
The pre-heating temperature is started in the soldering position (预热温度从焊接位置开始).
This “pre-heating curve” is absolutely imperative for some soldering applicants. 对于一些焊接应用，预热曲线相当重要。

For example, a soldering point that was first covered with soldering paste cannot or should not be heated up immediately to the melting temperature (被焊锡膏所覆盖的第一个焊点，不能也不该被立即加热到熔化温度); the flux content would evaporate immediately if the soldering iron was heated up very quickly (如果焊头加热过快，助焊剂将立即蒸发）. There is a danger that soldering balls are formed on the soldering point and/or the circuit board (可能会有在焊盘或者电路板上形成焊珠的危险).

Heating temperature:加热温度
This is where the temperature for the soldering iron, which should be reached after the pre-heating phase, can be set (see chart, red area). If the process is programmed without preheating, the heating process starts directly from the respective temperature of the soldering iron.(如果过程中未设置预热，加热过程将直接从焊头的预期温度开始)
The heating temperature is monitored (监控) during the soldering and/or heating process.
The curve shown above shows the temperature behaviour of the soldering iron and is not the same as the temperature curve measured on the product! (以上曲线展示了焊头的温度特性，它和产品上测得的温度不相同)。

Pre-heating time 预热时间
A time for the soldering iron, which should be pass before the actual heating starts (在实际加热开始前必须经过的), can be set here in seconds. In this phase the soldering iron heats up to the pre-heating temperature set in the previous menu (在这个阶段，焊头加热至前一菜单所设置的预热温度).
The pre-heating time determines how long the soldering iron should be pre-heated and at what temperature (预热时间决定了焊头被加热多久以及在什么温度). The pre-heated time is started in the soldering position. Pre-heating time and heating time are added together.

Heating time 加热时间
This is where the heating time is set in seconds. The heating time define the time in which the temperature controller heats the soldering iron to the defined heating temperature (加热时间决定了温度控制器加热至设定温度的时间) and holds the soldering iron to the defined heating temperature and holds the set temperature (以及保持焊头至设定温度和保持设定温度的时间).

Lesson 4

Overmolding process 注塑工艺

Word Service Station 词语加油站

impedance [im'pidəns] n. 阻抗 ｜ terrible [ˈterəbl] adj. 令人极不愉快的

scrap [skræp] v. 报废 ｜ brainstorming ['brein.stɔrmiŋ] adj. 集思广益的

solution [sə'luʃən] n.方案 ｜ attribute [ˈætriˌbjuːt] v. 把…归因于

abnormal [æbˈnɒrm(ə)l] adj.异常的 ｜ PA= polyamide 聚酰胺

pressure ['preʃər] n. 压力｜experience [ik'spiriəns] n. 经验

frequency ['frikwənsi] n. 频率｜ injection [in'dʒekʃ(ə)n] n. 注射

moisture [ˈmɔɪstʃə(r)] content n. 含水率｜ insulation [.insə'leiʃ(ə)n] n.绝缘

approach [ə'proʊtʃ] n. 方法｜confirmation [.kɑnfər'meiʃ(ə)n] n. 确认

Verification [ˌverifi'keiʃ(ə)n] n.验证｜Hypothesis [hai'pɑθəsis] n. 假设

Contrary [ˈkɒntrəri] n. 反面 ｜ vital ['vait(ə)l] adj.至关重要的

Fantastic [fæn'tæstɪk] adj. 极好的 ｜ immediately [i'midiətli] adv. 立即

Abundant [ə'bʌndənt] adj. 丰富的
 

Overmolding process 注塑工艺

 
Scene 1

Mr. Zhang asked Brent to his office for talking about the high scrap rate in products.

Zhang: We’ve got to come up with a way to solve this problem!(我们得想出个办法来解决问题！) You know how many Elisonstack assemblies we’ve scrapped every day, because of its terrible impedance failure?

Brent: Well, Mr. Zhang. Actually only a few of them was scrapped (只有一小部分被报废) and most we can rework.

Zhang: Don’t you think over the reworking time on it? (你难道没有考虑过返工时间吗?) Don’t you know how much we should pay each operator? Nearly 8 Euros per hour!

Brent: Yes, I know. We need to do some brainstorming to come up the solution for our products (我们需要进行集思广益，以想出对于我们产品的办法).

Zhang: Exactly! Just do it.

 
Scene 2

**Zhang: **Caspar, could we have your comments on the impedance failure? Edward, please write it down on the white board.

Caspar: All right. I think one of the main causes of low impedance in Elisonstack is (造成Elisonstack阻抗过低的原因之一是...), some new operators are hired in this period of time. As you know, from our statistic before, some mistakes often came from the new guys.

Dennis: Sorry, I can’t agree with you. Even if we hire some new employees in the last month, we still can’t attribute the low passed yield to the new operators(我们仍不能将低合格率归因于新员工). What we should focus on is the machine rather than man(我们要聚焦于机器而不是人). The wrong set-up overmolding parameter would lead to the abnormal pressure on the PA material in shaping process (错误的注塑设定参数，将导致成形过程中对PA材料的不当压力).

Edward: That’s true; in terms of this I have experience in my last job (从我上一份工作的经验来看). The impact of high temperature will be more obvious if the bulk cable works in much higher frequency. That is reason that our raw cable is sold at slightly high prices (这是我们的原电缆售价如此之高的原因).

Zhang: Well, what do you suggest?

Edward: Basing on the Overmolding principle, the following 3 aspects are the foremost on the Overmolding performance(在注塑表现方面，以下三个方面最重要): injection temperature, injection pressure and moisture content of plastic particle (注入温度，温度压力和塑料粒子含水率). The injection temperature determines the melting status(熔化状态) of plastic particle, and the flow rate(流动率) will decrease if it is too low. On the contrary (相反的是), the hot temperature will melt the insulation inside the wire, and make it shrink too much.

Dennis: That’s right. I’ve checked the default temperature and make sure it is a little bit higher than the limits of PVC insulation. So from middle shift yesterday, I have already decreased it lower than default value.

Caspar: But didn’t you see the failure statistic last night, we still have some failure parts. How do you explain that?

Dennis: Come on, be reasonable (你得讲点道理). We should work out for it together. How can you say like that!

Zhang: Exactly! Caspar, I’m not interested in the doubt. I’m more interested in the being able to fix the issue. Please keep on (请继续), Edward.

Edward: Thank you. The 2nd factor, the injection pressure is as same important as the injection temperature. The Overmolding will be not full under the low pressure condition (在低压条件下，注塑将不饱满). And the insulation is also pressed heavily under the high pressure.

Zhang: Could we find the most suitable value on the injection pressure and temperature?

Edward: No so easy, the best approach is the DOE, Design of Experiments (最好的方法是试验功能设计). What we need to do is: confirmation of vital processes(关键过程确认), analysis for input and output in process (过程输入输出分析), Matrix analysis (矩阵分析), ***Verification of Hypothesis Testing (假设验证) ***and ….

Zhang: Wait, wait. Could you make a summary and form the report to me?

Edward: Sure, no problem.

Dennis: But for the moisture content in PA particle, it is a good suggestion from Edward. I have had it tested and found a little higher than nominal value. Pre-heating of PA material is a solution to reduce the moisture content (对PA料的预热是降低含水率的方法).

Zhang: Sounds fantastic! Your idea is great. Please carry out the measures immediately; we have an abundance of orders from next month (从下月起我们有大量的订单).

Dennis: With pleasure.