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Steps in Preparing a Presentation

Step 1 prepare for the presentation

First, determine your audience: who will attend? How many people will attend?

then define the purpose of the presentation: determine how much information you can present in the time allotted, what you want the audience to learn from your presentation.

Step 2: present the presentation

Strategies to help you do this include the following:

- Presentation of data and facts

- Read quotes from experts

- Contact personal experience

The most important part is spoken language: enthusiasm, clarity, simple presentation… body language: eye contact, facial expressions, walking…use of aids: powerpoint, pictures pictures, graphs…

Step 3: End the presentation

You reinforce the main points you have communicated, you will help the audience remember them, provide materials or gifts, keep in touch with the participants

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Bearing:

Hello, today I will introduce you to some bearings that I have learned: ball bearing, straight roller bearing, tapered roller bearing, thrust roller bearing, rolling contact bearing. At first, I don’t know much about the features and functions of these bearings, but when the sellers explained more carefully, I understood them very well. Ball bearings use spherial roller to support axial and radial motion while straight roller bearings use cylindrical to support radial motion. Meanwhile, tapered roller bearings are for supporting radial forces and moderate thrust forces using conical rollers. Thrush roller bearings serves to support thrust motion using barel shaped rollers. A rolling contact bearing is also called an anti-friction bearing due to its low friction characteristic. That’s all I know.

Coupling:

Hello, today I will introduce you to some couplings that I have learned. There are 2 types of coupling: flexible coupling and rigid coupling. A flexible coupling can help reduce noise and unwanted vibrations. A beam coupling is a flexible coupling that are the most common flexible couplings. They are cut in spiral shape and can accommodate several degrees of shaft offset. Rigid couplings align the shafts with each other. They also maximize performance and efficiency.Sleeve-style couplings are the most common rigid couplings. It is used to link the parts together, making the machine structure easy to open and close, reduce dynamic loads, and prevent overload when operating.

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I would like to compare two types of drives which are chain drives and belt drives. Firstly, belt drive transmits powers from one shaft to another by means of pulleys, but chain drive transmits powers between parallel shafts. Secondly, belt drive is made of rubber and plastic while chain drive is made of metal. Thirdly, belt drive reduces noise and vibration but chain drive causes noise and vibrations. Unlike chain drive, belt drive tension is affected. Belt drive needn’t  to lubricate while chain drive requires frequent lubrication. Last, belt drive has low efficiency while chain drive has high efficiency.

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There are 5 types of gears that we have learned in the lesson. They are spur gear, helical gears, worm and worm gears, rack and pinion gears, bevel gears. Firstly, spur gears are also the most common and simplest type of gears. They are used in low speed applications. It cannot control noise at high speed. Secondly, helical gears have some outstanding features such as stronger and smoother than spur gears. They can reduce noise. Thirdly, worm and worm gears have just one continuous tooth, they can reduce speed. Regarding rack and pinion gears are a circular gear engaging a linear gear to convert rotational motion to linear motion. Lastly, bevel gears have a conical form. They often transmit rotational power through shafts at an angle, normally 90 degrees.

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Today, I would like to compare CAD and manual drafting. CAD is the creation and handing of pictures on a computer to assist engineers in design and drafting. Manual drafting is the practice of creating drawings by hand with pencil or ink on a media such as paper or polyester film using drafting equipment. While CAD is used for the quick layout of a preliminary design and necessary changes,  manual drafting is used for single-detailed drafting.CAD has high accuracy and reduced errors but manual drafting is easy misreading. While CAD is easy using and flexible, manual drafting is very time consuming. That’s all I know.

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Today, would like to describe a specific CAD program.  The name of the CAD program is Auto CAD. Auto CAD is a computer-aided design software developed by the Autodesk company. Its features are drawing and designing 2D and 3D objects, editing pre-existing drawings quickly and accurately, simulation…Its functions are to design and build 2D drawings, car design, and interior design,... its advantages are easy to creat and fix errors, more intuitive, save and reuse drawings more easily with a hard disk or CD, increased accuracy, easy analysis, simulation and testing of 3D models. Its disavantages are time and cost for implementing a CAD system is large, time and cost of training large CAD users, maintence and upgrade costs for CAD software are relatively large. That’s all I know.

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The check valve is made of cast iron.

First, this stage means that hot liquid material is poured into a container and cooled to make the correct shape.

Secondly, the cast iron is turned on a machine called a lathe.

Next, in this step holes are made using a drill.

After drilling, a surface is covered with paint.

When the paint is dry, the part are bolted together using nuts and bolts.

The final step is inspection. The work is checked carefully to make sure that the part has been made properly.

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Good morning. As I know, there are 7 types of plastic with different uses and features including: PET, HDPE, PVC, LDPE, PP, PS, and  OTHER PLASTIC. The first one is PET. Its code is number 1. It is strong and recyclable. We use PET to make manufacture food and drink packaging. The second one is HDPE. Its code is number 2. HDPE plastic is hard resistant to impact and heat, recyclable. So it is used for shampoo bottles, grocey bags, milk jugs. Thirdly, PVC’s code is number 3. PVC its versatile properties, such as lightness, durability, and ease of process ability. PVC is used in the building, cleaning products and sheetings. LDPE’s code is number 4. LDPE is easy and cheap to produce. It is used to make plastic bags, bread bags and plastic films. PP’s code is number 5. PP is a hard and sturdy plastic, and resistant to heat. It is used to make car parts, yogurt containers, straws and hangers. PS’s code is number 6. This is an easy to create plastic, quite expensive, very toxic at high temperatures. It is used to take-away and hard packaging, toys and beverage cups. Finally, PC will be included in group number 7. PC is used to buid strong, tough products, baby bottles, nylon and CDs.

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As you can see in the figure, this is the process of extrusion moulding. There are 6 steps in this process. First, we move the polymer pellets from the hopper to the cylinder. Secondly, an electric motor turns the screw in the extrusion moulder. Third, the cord polymer pellets move along the cylinder. Next, heaters warm the polymer pellets to turn them into a liquid. Beside, the warm, soft molten polymer moves along the cylinder. Finally, the machine pushes the molten polymer out into the mould.

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The common problems of platic injection moulding and give some solutions

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The common problems of platic injection moulding and give some solutions

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Typical problems of plastic injection are: Short shot, Void, Air Trap, . To understand better let's go to each problem one by one.Short shots are a phenomenon in which the mold cavity cannot be completely filled. As a result, parts appear incomplete. To solve this problem we need to ensure sufficient supply of raw materials for the casting process. Next, voids is inappropriate molding pressure to force trapped air out of the mold cavity. This problem we have to increase the pressure of the compression chamber to solve. Finally, Air traps are that air is trapped in the cavity to create bubbles in the part. To solve this problem, it is necessary to install a vibrator so that the bubbles in the melted plastic are removed before being put into the mold.

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Write a paragraph to present a maintenance checklist of a machine tool.

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Write a paragraph to present a maintenance checklist of a machine tool.

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This is a high performance cutter. it can cut with very high productivity and the product output is 3 times that of ordinary cutter. This machine is specialized for cutting solid cylindrical iron ingots. because of operating in conditions with a lot of chips, iron dust, high engine and blade temperature. In order for the machine to function properly and avoid breakdowns, regular maintenance is required. First of all, it is necessary to sweep the chips daily after work to prevent dirty chips from sticking to the engine causing the engine to overheat leading to a short circuit. Check weekly and add enough coolant to prevent damage to the workpiece and cutting edge. working . monthly, check the machine shaft for cracks or open circuit to avoid accidents while working.