Q.
With diagrams, explain the various types of water trap in the residential drainage system.
A.
Main function of water traps here.
Types of Traps:
The three types of traps are P-trap, Q-trap and S-trap as shown in below. A trap essentially consists of U-tube, which retains water, acting as a seal between the foul gases (inside the pipe) and outside atmosphere. They are largely used for baths, sinks and laboratories. In all such needs, they are made with enlarged mouth, so that the waste pipe may be thoroughly flushed out.
P Trap
Q Trap
S Trap
Floor Trap
Gully Trap
Intercepting Trap
- Floor traps,
- Gully trap, and
- Intercepting trap.
Floor traps : These traps are generally used to admit sullage from floors of kitchen and bathrooms. These are invariably provided with CI or GI stainless steel gratings at the top so as to prevent the entry of solid matter into drainpipe. Fig. shows the features of floor trap.
Gully traps : A gully trap is often provided at the junction of a room or a roof drain and other drain coming from bath, kitchen etc. The foul sullage from bath will enter through side inlet and the non- foul washings from room or rainwater from roof will enter from top and discharging into drains. Gully trap may either have a S-trap or P-trap. Fig. shows the features of gully trap.
Intercepting traps : An intercepting trap is often provided at the junction of a house sewer and a municipal sewer, so as to prevent entry of foul gases from of the municipal sewer into the house drainage system. It has a high water seal of 100 mm depth. Fig. shows the intercepting trap.
Ref:
Traps from The Water Treatment, available from