Joining Methods

Question 1

• widely used where the parts may need to be dismantled for repair or replacement and is non-permanent
• manufactured in brass, steel, stainless steel and plastics

Answer 1

Mechanical fasteners: machine screws

Question 2

• used for higher strength applications thus manufactured using high-grade alloy steel with rolled threads

Answer 2

Mechanical fasteners: socket screws

Question 3

• used for fast-assembly work and offer good resistance to loosening through vibration

Answer 3

Mechanical fasteners: self-tapping screws

Question 4

produces its mating thread by displacing the work material and used on softer ductile materials

Answer 4

thread-forming

Question 5

produces its mating thread by cutting the same way as tap

Answer 5

thread-cutting

Question 6

used in conjunction with a nut for heavier applications

Answer 6

bolts

Question 7

used with bolts to fasten parts together

Answer 7

nuts

Question 8

• distribute the tightening load over a wider area than does a bolt head, screw head or nut. It prevents damage and often provides a locking action.

Answer 8

Mechanical fasteners: washers

Question 9

• When inserted in the hole, it ensures that the pin remains securely in position and cannot work loose.
• being used to replace solid hinge pins, split pins, rivets and screws

Answer 9

Mechanical fasteners: spring tension pins

Question 10

• a process of joining metal parts by heating and running a low-melting point alloy between the two surfaces being joined

Answer 10

Soft Soldering

Question 11

are alloys of tin and lead. All the plain tin/lead solders become solid at 183°C. The temperature at which they become completely liquid depends on the composition, the temperature increasing as the lead content increases

Answer 11

Soft solders

Question 12

chemically removes the oxide film, has an acid base, and is highly corrosive. These fluxes are usually hydrochloric acid in which zinc has been dissolved to form zinc chloride, known as ‘killed spirits’.

Answer 12

Active flux

Question 13

used after the oxide film has been removed using emery cloth, to prevent the oxide film reforming.And, are usually resin-based.

Answer 13

Passive flux

Question 14

• process of joining metals in which, during or after heating, molten filler metal is drawn by capillary action into the space between closely adjacent surfaces of the parts being joined.
• used to join any combination of similar or dissimilar metals and results in a high-strength joint of good reliability.

Answer 14

Brazing

Question 15

is a cheap and readily available flux and is widely used for general applications.

Answer 15

Borax

Question 16

• used to establish a permanent bond between two joint surfaces. It is the modern term for glueing, and the technique is used to join metals to themselves and also a wide variety of metallic and non-metallic materials.

Answer 16

Adhesive bonding