Environmental Engineering Multiple Choice Questions on “Types of Pipes”.
1. Which of the following is incorrect regarding cast iron pipes?
a) They are non corrosive
b) They are durable
c) They can be produced by centrifugal process
d) Their length varies from 80-100cm
Answer: d
Clarification: Cast iron pipes are resistant to corrosion, has long life, can be produced by the centrifugal process and their length varies from 3-6m.
2. Horizontally cast iron pipes are called _________
a) Mcwane pipes
b) Pit cast pipes
c) Galvanized iron pipes
d) Wrought iron pipes
Answer: a
Clarification: The cast iron pipes which are horizontally cast are called Mcwane pipes while those that are vertically cast are called as Pit cast pipes.
3. Mcwane pipes are ___ stronger in tension than Pit cast pipes.
a) 20%
b) 30%
c) 50%
d) 100%
Answer: d
Clarification: Mcwane pipes are 100% stronger in tension and 50% stronger in rupture than Pit cast pipes.
4. The enlarged end of a cast iron pipe is called ________
a) Lead
b) Socket
c) Hemp
d) Spigot end
Answer: b
Clarification: The enlarged end of a cast iron pipe is called Socket. It accommodates the spigot end.
5. What is the quantity of lead required for a 15cm diameter cast iron pipe?
a) 5kg
b) 10kg
c) 15kg
d) 20kg
Answer: a
Clarification: The quantity of lead required depends on the diameter of cast iron pipe. For 15cm diameter cast iron pipe, it requires 5kg lead, whereas for 120 cm diameter pipe, it requires 55kg lead.
6. Which of the following joint is called run lead joint?
a) Tyton joint
b) Coupled joint
c) Spigot and socket joint
d) Flanged joint
Answer: c
Clarification: Spigot and socket joint is called run lead joint as it contains molten lead, which is heated at 4000C and applied at the joints.
7. In which of the following joint, pipes do not have sockets or spigots?
a) Tyton joint
b) Coupled joint
c) Spigot and socket joint
d) Expansion joint
Answer: b
Clarification: In Coupled joints, pipes do not have sockets or spigots. There are two types of coupling joints- dresser coupling and victaulic coupling joints. These joints are highly flexible.
8. Which of the following joint is highly influenced by temperature?
a) Tyton joint
b) Coupled joint
c) Spigot and socket joint
d) Expansion joint
Answer: d
Clarification: Expansion joints allow the expansion and contraction of the joint due to change in temperature. The space between the socket and spigot in this joint is filled with an elastic gasket.
9. Which of the following is the advantage of cast iron pipes?
a) They are subjected to tuberculation in certain water
b) They are fragile
c) They are heavier
d) They are resistant to corrosion.
Answer: d
Clarification: The cast iron pipes are subjected to tuberculation which reduces their carrying capacity, they are fragile, heavier, resulting in more cost when their diameter exceeds 120cm and they are resistant to corrosion.
10. Which grade of concrete is used in Reinforced concrete pipes?
a) M10
b) M15
c) M20
d) M25
Answer: d
Clarification: M20 grade of concrete is used for making Reinforced concrete pipes with longitudinal reinforcement equal to at least 0.25% of cross sectional area of concrete.
11. The pre-stressed concrete pipes are used for heads ____
a) <8m
b) <61m
c) >60m
d) <35m
Answer: c
Clarification: The pre-stressed concrete pipes are used for heads greater than 60m, plain cement concrete up to 7m and reinforced concrete up to 60m.
12. Which of the following is correct regarding Cement concrete pipes?
a) They are corrosive
b) The maintenance cost is high
c) Unreinforced pipes are liable to tensile crack
d) It is easy to repair them
Answer: c
Clarification: Cement concrete pipes are anti corrosive with low maintenance cost, difficult to repair and the unreinforced pipes are subjected to tensile cracks.
13. The tensile strength of Asbestos cement pipes is _____
a) 200kg/cm2
b) 300kg/cm2
c) 400kg/cm2
d) 600kg/cm2
Answer: a
Clarification: The tensile strength of Asbestos cement pipes is 200kg/cm2 and its compressive strength is 600kg/cm2.
14. Which of the following is a disadvantage of Asbestos cement pipe?
a) They are light weight
b) They have smooth internal surface
c) They are anti corrosive
d) They are soft and brittle.
Answer: d
Clarification: The disadvantage of Asbestos cement pipe is that it is soft and brittle, so they are weak under impact loading due to moving traffic.
15. Lead pipes are used in water supply mains.
a) True
b) False
Answer: b
Clarification: Lead pipes are used in service connection and in internal plumbing, but are not used in water supply mains due to the poisonous effect of lead.