SANITARY FITTINGS
The sanitary fitting are required in house drainage for the efficient collection and removal of waste water from the house to house drain. The following are some of the sanitary fitting:
1. Traps.
2. Water closets.
3. Flushing cisterns.
4. Urinals.
5. Inspection chambers.
6. Anti-syphonage pipe
Traps
A trap is a depressed or bent sanitary fitting which always remains full of water (water seal). The function of a trap is to prevent the entry of bad smelling gases into the house. The effectiveness depends upon the depth of water seal which varies from 25 to 75 mm.
Requirements of good trap:
1. It should be capable of being easily cleaned.
2. It should be easily fixed with the drain.
3. It should be of simple construction.
4. It should possess self-cleansing property.
5. It should possess adequate water seal to fulfil the purpose of installation
6. It should be free from any inside projection which are likely to obstruct the passage of flow of sewage.
7.
The internal and external surfaces should be of smooth finish.
Types of Traps
1. Classification according to shape as shown in Fig
(a) P-trap (b) Q-trap. (c) S-trap.
2. Classification according to use as shown in Fig.
(a) Floor trap or Nanhi trap:
Made of cast iron and placed in bathrooms kitchens, sinks etc. A floor trap, commonly knowing as nanhi trap is used to collect wash water from floors kitchens and bath rooms. It forms the starting point of waste water floor it is made of cast iron, with gravity at top to exclude entry of solid mater of big size. This cover can be removed to do frequent cleaning of the trap these traps have small water seal.
(b) Gully trap:
These are special types of traps which disconnect sludge drain (collected from the baths, kitchens etc) from the main drainage system it is either made of stone ware or of cast iron. Stone ware gully trap is of square section at the top on which C I grating is fitted. Water seal of 60 to 70 m is usually provided. It may have either a S trap and P trap. A gully trap is provided, at the external face of a wall thus receives waste water from baths, kitchens etc, and pass it on to the house drain carrying excremental discharging from water closets etc Made of stone wave and C.I. grating is provided. It is placed near the external face of wall and kept slightly higher level than ground level
(c) Intercepting trap:
This is a special type of trap is provided at the junction of house drain with the public sewer or septic tank. It is thus provided in the last manhole of the house drainage system. It is thus provided in the last manhole of the house drainage system. t has a deep water seal of 100 mm, so as to effectively prevent the entry of sewer gases from public sewer line into the house drain. The trap has an opening at the top, called the cleaning eye or rodding arm, having a tight fitting plug for frequent cleaning of the trap.
(d) Grease Trap:
Such traps are used only in large hotels, restaurants or industries where large quantities of oily wastes are expected to enter the water flow. If the oily or greasy matter is not separated it will stick to the building drainage system resulting in the formation of ugly scum and consequent obstruction to re aeration. A grease trap is either a masonry or cast iron chamber, with a vent pipe or Tee pipe at the outlet end. Because of sudden increase in the area of flow at entry, the velocity of low is reduced, resulting in the separation of oily and greasy matter from the wastewater.
