Unit 5 manufacture of pipelines

1. Study the vocabulary.

1. arc welding (electric arc welding) 2. butt 3. butt welded 4. collar 5. contraction 6. exert 7. expansion 8. forge 9. forging 10. fusion welding 11. lap weld 12. leaky 13. length 14. overlap 15. oxyacetylene welding 16. plain end 17. pipe coupling 18. pipe tongs 19. punch 20. reheating 21. rolling 22. rotary piercer 23. rough tube 24. scarf 25. screwed connection 26. solid billet 27. threaded 28. welded pipe 29. weldless (seamless) pipe 30. withstand 31. wrench

1. дуговая электросварка 2. стык; соединять впритык 3. сваренный встык 4. манжета 5. усадка труб, сжатие 6. действовать 7. расширение 8. выковывать, ковать 9. ковка; горячая (объёмная) штамповка 10. сварка плавлением 11. нахлёсточный сварной шов 12. неплотный, негерметичный; пропускающий 13. отрезок трубы 14. частично покрывать; заходить один за другой, перекрывать 15. сварка автогенная 16. гладкий, ненарезанный конец (трубы) 17. трубная соединительная муфта; стык трубопровода 18. ключ для труб 19. кернер, пробойник; пуансон; штемпель 20. повторный нагрев, дожигательный 21. катание, прокатка, прокатывание 22. косовалковый прошивной стан 23. гильза (прошитая трубная заготовка) 24. скашивать; отесывать края; делать пазы, выемки; соединять в косой стык 25. винтовое соединение 26. целиковая (сплошная) заготовка 27. с нарезкой, с резьбой, нарезной 28. сварная труба 29. бесшовная (цельнотянутая) труба 30. выдерживать 31. гаечный ключ

2. Find out the pronunciation of the following words.

oxyacetylene to forge pipe coupling

to exert billet

to pierce wrenches coupling

III. Translate the following words.

a) to process - process; to import - import; to export - export; to increase - increase; but: to deposit - deposit;

b) deep - depth; strong - strength; long - lengths; wide - width; to grow - growth;

c) to form - form; to weld - weld; to shape - shape; to thread - thread;

to seam - seam; to line - line; to use - use.

IV Read and translate the following text. Manufacture of pipe lines

Modern tube making is divided into two classes, welded pipes and weldless or seamless pipes. In the former cases the tube is made from plate or strip bent in the circular form and welded along the seam. In the latter the pipe is made from a solid billet forged into the hollow form.

Welded pipes can again be subdivided into three large classes: butt welded, lap welded and electrically welded.

The butt welding process consists in forming the strip into the circular form in such a manner that the edges of the strip meet squarely without overlapping.

In lap welding the strip is scarfed at the edges, so that when bent into shape the two edges overlap, thus giving a comparatively large welding surface as compared with the thickness of the strip.

There are several types of electric welding all of which consist of converting the strip into the circular form and there after welding along the seam by arc or fusion welding.

In the weldless processes the heated billets are pierced by punches, or rotary piercers, thus forming rough thick tubes considerably shorter and thicker than the size required. These rough tubes are extended in length and reduced in thickness by passing through rolling or forging processes. This is generally carried out without reheating.

Welded or seamless pipe lengths are then to be connected to each other by means of screwed connections or by welding.

Screw pipe is threaded on each end and joined by a collar. The threaded pipe is inserted in the collar and drawn as tightly as possible by using pipe tongs which are nothing more than large wrenches. The joint so made is often defected and leaky due to the difficulty in obtaining well matched threads.

Up to the time of the World War II practically all joints of pipe lines were of the screwed and coupled type. The progress made in recent years in the technique of welding, which has resulted in low costs and high efficiency has led to welded joints for pipe line being extensively used. A number of important pipe lines have been constructed by welding the joints with the aid of oxyacetylene or electric arc welding. Welded joints may be as strong as the pipe itself and since the pipe is not weakened by the cutting of threads, it may be somewhat lighter weight than when screw joints are used. Because of this since no collars or other fittings are needed welded pipes are considered to be cheaper. If the welding is properly done, welded lines are also more secure against leakage.

Most lines being laid at present are a combination of the welded and plain end pipes. Plain end pipes are called so because neither end of any section of the pipe is threaded. The joints are connected by couplings. The pipe is welded into lengths usually 130 feet (and even much more) and joined with a plain end coupling. This allows for expansion and contraction in lines. An ideal pipe line would be a continuous pipe able to withstand all common forms of corrosion and all reasonable forces exerted upon it.