Подберите к каждому предложению похожее по смыслу предложение, данное справа. Переведите их на русский язык

 

1) Vent holes allow the gases to escape from the mold. 2) The two halves of the mold are easily disjoined when we apply the parting sand over the parting surface. 3) Vent holes are sometimes not required if the sand mold is properly rammed. 4) The molten metal flows into the mold cavity through the gating system. 5) One of the final operations in the foundry is cleaning the casting from risers and gates.

1) Pouring basin, runner, gate sprue and gates are formed in the sand mold for the flow of the metal to the mold cavity. 2) Some small openings made in the sand help the gases to come out the mold. 3) In the cleaning department gates and riser are removed from the casting. 4) It is not necessary to make vent holes when the sand had been packed in the correct way. 5) The parting sand on the joint will not allow the mold halves to stick.

 

 

30. Закончите предложения, выбрав соответствующий вариант,\. Переведите

 

1) Parting sand is usually in the form of ….

2) The purpose of the riser is to compensate for ….

3) An opening on the top of the mold for pouring the metal is called ….

4) The gating system includes the pouring basin, the gate sprue, the gate and the ….

5) Vent holes are made in the sand ….

6) The gating system must be produced in the mold ….

___________ _

runner; properly; the pouring basin; the shrinkage of the metal during the solidifying process; fine powder; in several places.

 

31. Соедините две части предложения союзом цели «in order to …» – для того чтобы; чтобы. Запишите полученные предложения. Переведите их

 

f.e. Ladles of different sizes are used in the foundry, … to pour the molten metal into molds.

Ladles of different sizes are used in the foundry in order to pour the molten metal into molds.

 

1) Clay is mixed with silica sand, … to make the molding mixture strong.

2) Facing material is applied for the mold cavity, … to prevent the sand from sticking to the hot metal.

3) The molding sand must be refractory, … to withstand high temperature of the poured metal.

4) Gating system is produced in the sand mold, … to supply the molten metal to the mold cavity.

 

Прочтите текст D, переведите его и скажите о каком процессе (формовке, заливке, трамбовке) идет речь

 

Text D

Ramming of the sand is necessary in order to make the sand retain its position (заставлять землю удерживать свое положение) in the mold. The sand is rammed around the pattern. Long practice is necessary for proper ramming. The proper ramming depends upon the molding sand used, the metal poured, and other factors. Ramming too hard will close up openings (vents) in the sand, so that steam and gases produced during pouring process cannot readily escape. This may cause blowholes in the casting. Too soft ramming will not give sufficient strength to the sand and mold surface. This may alloy the flow of molten metal to make the casting larger than the pattern or may cause other casting defects.

The joint and the bottom parts of the mold must be rammed harder than the upper portions.

 

Unknown words to the text D:

hard – плотно, плотный

soft – слабо, слабый

readily – быстро, легко

to cause – вызывать

blowhole – раковина.

 

33. Используя текст D, ответьте по-английски на следующие вопросы

 

1) Where is the sand rammed?

2) Is long practice an important factor for producing proper ramming?

3) What other factors does the proper ramming depend upon?

4) What defects may too hard ramming and too soft ramming cause?

5) What parts of the mold must be rammed harder?

 

34. Распределите пункты плана в последовательности, соответствующей содержанию текста D

 

a) Purpose of ramming.

b) Ramming of different parts of the mold.

c) Defects in ramming.

d) Requirements to ramming.

 

Озаглавьте по-английски текст D.

 

PART IV

TYPES OF MOLDS