1. a hollow object or open device that fits or holds an object
1. a small, often standardized, part installed in a larger part (device)
2. a projecting rim or edge, usually drilled with holes to allow bolting to other fittings
2. a substance in which another substance is dissolved
3. a coupling device that allows pipes to be connected
3. join metallic parts by fusion alloys
4. a depression on a surface
4. form metal into a particular shape
5. semisolid or solid complex mixture of organic compounds having no definite melting point
5. bend or mold into shape
6. gradual decrease in thickness or width of an object
6. to solder together using a hard alloy with a high melting point
7. a continuous rib as on a pipe
7. hardened by the action of heat
Complete the table using the terms and fill in the missing gaps in the following passage.
Joining methods
Mechanical
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. _____________.
Match the methods with the description.
Example:6 – C
1.
threaded
A.
joining light-wall steel and copper pipe, metallic or nonmetallic that is being cut or rolled
2.
welded
B.
consist of an inner elastometric gasket and an outer metallic sleeve with integral bolts for compressing the gasket.
3.
soldered
C.
a substance that hardens under heat to bond pipes
4.
crimped (grooved)
D.
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.
5.
compressed
E.
is a metal-joining process wherein coalescence (ñîåäèíåíèå) is produced by heating to suitable temperatures with or without the use of filler metal.
6.
cemented
F.
a continuous helical (âèíòîâîå çóá÷àòîå êîëåñî) has threads on each end, making it possible to screw two pieces of pipe together.
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
Ductile
Malleable
Corrosion resistant
Good conductor of electricity
cast (ductile) iron
malleable (wrought) iron
copper
lead
brass
cast steel
plastic
√
√
√
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)
