Упражнения

Упр. 1.Найдите в тексте английские эквиваленты данных слов и выражений:

1. растворяться, 2. горючий газ, 3. баллон, 4. сжиженный газ, 5. бензин, 6. баллонный газ, 7. нефть, 8. горение, 9. конструкция, 10.теплотворная способность

Упр.2. Вставьте нужное слово или словосочетание:

1. Common fuel gases are used for cutting and welding … state. 2. The gas … should be kept vertical with its valve on top. 3. Acetylene is transported in special cylinders designed to keep the gas … .4. The acetylene … into acetone. 5. At a high pressure acetylene may … . 6. Acetylene gives the highest … of any commonly used gaseous fuels. 7.The gasoline is … from a pressure tank. 8. … is good for underwater welding and cutting. 9. MAPP gas can be used at much higher … than acetylene. 10. Most propane tips are of … design.

Упр. 3. Переведите на АЯ:

1. Кислород химическим способом соединяют с горючим газом, чтобы получить высокую температуру горения. 2.Кислород можно получать из сжиженного воздуха. 3. Пропан обеспечивает быструю и чистую резку при использовании инжекторной горелки. 4. При использовании пропана приходится менять не только наконечник, но и горелку, чтобы получить хорошее качество работы. 5.При использовании пропилена практически не нужно очищать наконечник горелки. 6. Процесс окисления обычно называют горением. 7. Продукт окисления водорода – вода. 8. Кислородно-бензиновые горелки обеспечивают хорошее качество работы, особенно там, где нет баллонного газа. 9. Водород обеспечивает высокую температуру пламени при нагревании большой массы материала. 10. При сжигании в кислороде ацетилен дает температуру до 3500º С.

Упр.4. Найдите синонимы к следующим словам:

Burning, nozzle, housing, adjust, tank

Unit 22. HAZARDS IN OXY-ACETYLELE WELDING

Oxy-acetylene welding can be dangerous: severe and fatal burns, violent building destroying explosions can result from inattention and carelessness. Before using an oxyacetylene set, ensure that flammable materials such as grease, oil, paint, sawdust etc are cleared from the area and workpieces. Oil and grease can spontaneously ignite and burn violently in the presence of pure oxygen. It is important to wear clean clothing free from oil and grease. Do not roll up sleeves or trouser legs as the rolled cuffs could catch sparks. Many operators use a welding cap or a baseball cap put on backwards to stop sparks from lodging in hair or going down the neck of the shirt. Wear shaded goggles with enclosed sides or a shield with a minimum #4 shaded lens to protect your eyes from glare, flying sparks and splatter. Sunglasses are not adequate. Wear leather gloves to protect your hands from burns.

Fluxes, filler rods and base metals heated during welding and brazing release toxic fumes, acetylene gas is highly explosive, so ensure adequate ventilation before welding. Acetylene is often described as having a sweet garlic-like smell. If you can smell it in the air and do not know where it is coming from, evacuate the area immediately. Call the fire department outside of the area as a phone call may start a fire or explosion in vapors. Fuel gases heavier than air, such as Propane, Propylene, MAPP and Butane can pool in lower areas if allowed to escape. In confined spaces respirator masks designed for welding can be used. Never weld on containers that have previously had toxic or inflammable substances. Do not weld inside enclosed spaces or in tanks where the only ventilation comes from above – you might suffocate. Some fuel gases have an anaesthetic-type effect when breathed in.

Before using an oxyacetylene setup, ensure that a fire extinguisher in good working order is present. Water does not work on oil and grease, but a bucket of water can be handy for putting out small wood fires. Sand can also be used to quench fires. It is also generally handy to have at least one pair of heavy pliers around for moving hot things if necessary. Be sure your workpiece is well organized before starting. Have tools laid out where they can be easily reached and make sure there is nothing that you can trip up on. A fireproof surface should be used for welding: steel table tops and firebricks are commonly used. Avoid distractions such as trying to have a conversation or listen to a radio sports commentary as you work.

When using fuel and oxygen tanks they should be fastened securely upright to a wall or a post or a portable cart. An oxygen tank is especially dangerous for the reason that the oxygen is at a pressure of 200 atmospheres when full, and if the tank falls over and its valve strikes something and is knocked off, the tank will become an extremely deadly flying missile propelled by the compressed oxygen. For this reason never move an oxygen tank around without its valve cap screwed in place.

On your oxyacetylene torch system there will be three types of valves: the tank valve, the regulator valve and the torch valve. There will be one of them for each gas. The gas in the tanks or cylinders is at high pressure. Oxygen cylinders are generally filled to something like 2200 psi. The regulator converts the high pressure gas to a low pressure stream suitable for welding.

Never lay an acetylene tank on its side while being used. It contains acetone in which the acetylene is dissolved. If the tank was laid down while being transported, it must be set upright, valve on top, and given enough time ( 30 minutes) for the acetone to settle back into the sorbent. If these precautions are not followed, acetone may be drawn into the gas lines, thus creating a space in the top of the acetylene tank devoid of sorbent and the gaseous acetone in this void space may explosively decompose inside the tank causing damage to life and property

VOCABULARY

Ignite – воспламеняться

Regulator (valve) – редуктор газовый

Tank /cylinder valve – вентиль баллона

Pool - накапливаться

Suffocate - задушить

Fire-extinguisher огнетушитель

Garlic - чеснок

Pliers - клещи, щипцы

Missile – ракета

Quench – тушить, гасить

Fireproof - огнеупорный

Firebrick – огнеупорный кирпич

Sorbent – сорбент, впитывающее, поглощающее вещество

Void space – пустое пространство