1. Pronounce the following words. Pay special attention to the letters in bold.

2. Pay attention to the stress in the following words. □ shows the position of stress.

3. Read the text “Pipe Joints and Fittings”, do the exercises.

Pipe Joints and Fittings

Pipe and fittings are produced in a wide range of materials including: ductile or cast iron, malleable iron, brass, copper, cast steel, plastic and fiberglass. Pipe joints can be permanent or mechanically joined, allowing disconnection. Permanent joints involve welding or crimping metal pipe and cementing plastic pipe. Joints that can be taken apart include threaded,

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flanged and coupled designs. Flanges can be loose, threaded or welded to pipe ends and are used on metal and plastic pipe.

Threaded

Threading is one of the most popular and least expensive methods of joining steel pipes. The tapered male fitting is forced into the tapered female fitting.

Yielding metal creates a seal. Threads other than taper pipe threads can be used for piping connections where tightness of the joint depends on a seal weld or seating surface other than the threads. While threaded joints can be dismantled, it is preferable to use unions. Threaded pipe is available in sizes from 1/16 to 24 in.

Welded

Welded joints are commonly used with steel pipe because these joints are stronger and less prone to leakage than threaded and flanged joints. Also, this method does not add weight to the piping system as flanges do or require a pipe wall thick enough to be threaded.

Pipe up to 2-in. size is generally socket-fitting, fillet welded. Larger pipe 3- 36 in, is usually butt welded. The most common joint is the circumferential butt joint. During the welding procedure, to avoid entrance of welding material into the pipe, backing rings may be used.

Soldered

A soldered joint is a rigid, pressure-type joint made with a filter metal that, when heated to its melting point, is drawn into the annular space between pipes and fitting by capillary action. This type of joint is generally limited to pipe up to 8 in. because of the difficulty of applying heat evenly to the joint. Brazing is similar to soldering except higher heat is required for the filler metal. It is used where higher pressure ratings are required.

Compression

Compression couplings usually can be used with all types of pipe and do not require any pipe preparation. They consist of an inner elastometric gasket and an outer metallic sleeve with integral bolts for compressing the gasket. They are available for pipe up to 144-in. OD.

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Crimped or grooved

The use of mechanical joints in piping systems is becoming popular. A crimped joint is designed to join light-wall steel and copper pipe, metallic or nonmetallic that is capable of being cut or roll grooved up to 2-in.

Cemented

Solvent joining can be used on vinyl pipe and some others, available up to 12-in. Polyolefin and other pipes require heat fusion and are available up to 6-i. Fibreglass pipe requires an adhesive, resin impregnated fabric or threads to make a joint. It is readily available in sizes from 1/2 to 144-in.

(http://www. Wikipedia.org)

4. Find the synonyms to the following words.

Example: 11. procedure – A. method

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5. Solve the following crossword.

7

1

2

3 4

1

2

5

7

6

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6. Complete the table using the terms and fill in the missing gaps in the following passage.

Mechanical

Joining methods

Thermal

Adhesive

Pipes can be joined by three basic methods: 1. mechanical, 2.

_____________ and 3. __________________. Both the mechanical and 4.

_______________ methods can be further divided. The former method includes 5. _____________ and 6. ______________. The latter method can be broken down into

7. ________ and 8. _____________.

7. Match the methods with the description.

Example: 6 – C

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8. Read the mini-text “Metal Properties” and complete the table. Use the symbols √ (yes) and x (no). Use the information from Ex. 3.

Metal Properties

Metals are used for a variety of engineering purposes, depending on the properties of the metals. Certain common metals have malleable and ductile properties. If a metal is malleable it can be hammered or pressed into a new shape. Copper is a good example of this. It is also can be used for sheaths on electrical cables. Lead, like copper and tin, will resist corrosion.

Tin and wrought iron can be stretched, and also have malleable properties. The former is corrosion resistant, but wrought iron easily corrodes. Wrought iron can be used for chains and crane hooks. Neither of these two metals is a good conductor of electricity.

Cast iron is unlike the other metals because its shape cannot be altered by hammering, pressing or stretching and it is not corrosion resistant.

(Basic Technical English, Oxford University Press. 2002)

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9. Complete the table using the information from the text. Compare and analyze.

JOINING PIPES

Materials Properties Method Method Examples Of

Description Uses

10. Discussion: The topic of our discussion is “Pipe Jointings”. The monitoring packet includes four parts. Do the tasks. Afterwards you have 10–15 minutes to make a mini-report and present it.

Part 1 Checking vocabulary by means of reading comprehension

Fill in the gaps.

1.Pipe and fittings are made of different material ___________.

2.Pipe joints allow __________________________.

3.Joints can be ________ or _______________.

4.Flanges can be _________, __________ and _________.

5.Joints that can be taken apart include _____________.

Part 2 Detail reading: questions that ask for specific information

Answer the following questions.

1.Which are the most popular and least expensive methods of joining steel pipes?

2.When is threading used? Why?

3.When welded joints are used? What is the advantage of this method?

4.What is the most common joint in the welded method?

5.What is the difference between soldering and brazing?

6.Why can compression couplings be used with all types of pipe?

7.Why is the use of mechanical joints in piping systems becoming popular?

8.What method is used for fibreglass pipes, vinyl pipes and polyolefin pipes?

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Part 3 Main idea: checks the student’s comprehension of the text.

Fill in the following table.

Part 4 Interpretive questions – analyze and infer the text.

Discuss the following statement and prove your opinion.

Piping connections serve an important role in the operation of the system. Depending on the application, pipe connections can take a variety of forms.

11.  You will hear a man talking about arc welding process. For questions 1-4, choose the answer (A,B,C, or D) which fits best according to what your hear.

1 MIG stands for

AMetal Inner Gas Welding

BMild Inert Gas Welding

CMetal Inert Gas Welding

DMetal Inner Gas

2What is not mentioned as a part of arc welding unit? A gas shield

B power supply

C strength steel wire D drive rollers

3Thickness of wire depends on

Adiameter

Busage

Cpower supply

DMIG gun

4What is a main constituent of the machine? A unit

B gas C gun D bottle

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12. Discuss the following quotation and state your own opinion.

Corrugated pipe is one of the alternatives nowadays. Most importantly, corrugated pipe is durable and flexible enough that it can make it through even in the harshest Alaska winter. The shift in the round here is extreme, our projects need a pipe that can handle it. Corrugated pipe can and does handle it.

(Rick Green)

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UNIT 4

PIPELINE CORROSION

Corrosion is deterioration of intrinsic properties in a material due to reactions with its environment. It is the oxidation of metals reacting with water or oxygen. Weakening of iron due to oxidation of the iron atoms is a well-known example of electrochemical corrosion. This is commonly known as rust. This type of damage usually affects metallic materials, and typically produces oxide(s) and/or salt(s) of the original metal. Corrosion also includes the dissolution of ceramic materials and can refer to discoloration and weakening of polymers by the sun's ultraviolet light.

Lead-in

Pipeline corrosion. Look at this subject from different points of view. Examine the subject from each of the following angles:

•Describe it. (Have you seen it? What does it look like?)

•Compare it. (What is it similar to? What is it different to?)

•Analyze it.

•Associate it. (What does it remind you of? What do you associate it with?)