Types of Traps in Plumbing

A trap is a device which is used to prevent sewer gases from entering the buildings. The traps are located below or within a plumbing fixture and retains small amount of water. The retaining water creates a water seal which stops foul gases going back to the building from drain pipes. Therefore all plumbing fixtures such as sinks, washbasins, bathtubs and toilets etc. are equipped with traps. This article tells you the features of traps, various types of traps and water seal.   

A trap has following features. It may be manufactured as an integral trap with the appliance as in some models of European WC, or it may be a separate fitting called an attached trap, which is connected to waste or foul water outlet of appliances. The traps should be of a self-cleansing pattern. Traps for use in domestic waste should be convenient for cleaning. A good trap should maintain an efficient water seal under all conditions of flow.                     Various Types of Traps

1. Gully Trap:

These traps are constructed outside the building to carry waste water discharge from washbasin, sinks, bathroom etc. and are connected to the nearest building drain/sewer so that foul gases from sewer do not come to the house. These are deep seal traps, the depth of water seal should be 50 mm minimum. It also prevents the entry of cockroach and other insects from sewer line to waste pipes carrying waste water.

                                                        ( Gully Trap )

2. P. Trap:

This trap is used with Indian water closet (ORISSA Pattern). The traps are made from cast iron or UPV sheet. This trap also has water seal and prevents entry of foul gases to the house.   

                                                              ( P Trap)

3. S. Trap:

This trap is similar to P. trap and is used for fixing water closets in toilets. The only difference between P trap and S trap is that P. trap is used for outlet through the wall whereas S. trap is used for outlet through the floor. 

                                                                 ( S Trap )

4. Floor Trap or Nahini Trap:

This trap is provided in the floor to collect waste water from washbasin, shower, sink and bathroom etc. These are available in cast iron or UPVC material and have removable grating (JALI) on the top of the trap. The minimum depth of water seal should be 50 mm. 

                                                              ( Floor Trap )

5. Intercepting Trap:

this trap is provided at the last main hole of building sewerage to prevent entry of foul gases from public sewer to building sewer. It has a deep-water seal of 100 mm.

6. Grease Trap:

this trap is a device to collect the grease contents of waste and can be cleaned from the surface. This is generally used in food processing unit.

                                                              ( Grease Trap )

7. Bottle Trap:

This trap is used below washbasin and sinks to prevent entry of foul gases. 

                                                            ( Bottle Trap )

8. Q Trap:

This trap is used in toilet under water closet. It is almost similar to S trap and is used in upper storey other than ground floor.

Water Seal

Water seal in a trap is the depth of water which should be removed from a fully charge trap before gases at atmospheric pressure may pass from the waste pipe through trap into a building. The tape is useless unless they retain their seals at all times. The seal may be broken due to air compressor, momentum and evaporation. The trap in fittings in range is liable to siphonic action and each trap should be ventilated.   

The depth of water seal in various sanitary appliances is given below.
• Water closet 50 mm
• Floor trap 50 mm
Other fixtures are directly connected to the stack through branch waste pipe of diameter = 75 mm and 40 mm
• Hand-pour flushed type 20 mm

Original Thread :  http://www.gharexpert.com/articles/Waste-Water-Drainage-1790/Traps--Types-Uses_0.aspx

Meaning of DYN 11 on transformer nameplate

What does Dd0, Dyn11, YNd5 etc. mean?

First symbol/symbols, capital letters: HV winding connection.
Second symbol/symbols, small letters: LV winding connection.
Third symbol, number: Phase displacement expressed as the clock hour number.


Winding connection designations

High Voltage Always capital letters
Delta - D
Star - S
Interconnected star - Z
Neutral brought out - N

Low voltage Always small letters
Delta - d
Star - s
Interconnected star - z
Neutral brought out - n


Phase displacement
Phase rotation is always anti-clockwise. (international adopted convention)
Use the hour indicator as the indicating phase displacement angle. Because there are 12 hours on a clock, and a circle consists out of 360°, each hour represents 30°.
Thus 1 = 30°, 2 = 60°, 3 = 90°, 6 = 180° and 12 = 0° or 360°.
The minute hand is set on 12 o'clock and replaces the line to neutral voltage (sometimes imaginary) of the HV winding. This position is always the reference point.
Because rotation is anti-clockwise, 1 = 30° lagging (LV lags HV with 30°)and 11 = 330° lagging or 30° leading (LV leads HV with 30°)



To summarise:
Dd0
Delta connected HV winding, delta connected LV winding, no phase shift between HV and LV.
Dyn11
Delta connected HV winding, star connected LV winding with neutral brought out, LV is leading HV with 30°
YNd5
Star connected HV winding with neutral brought out, delta connected LV winding, LV lags HV with 150°

What is the meaning of GI pipe?

GI pipes (IS No: 1239; Part 1- 1990) are made from hot rolled coils of specified thickness. The pipes are fully galvanized. GI pipes are available in three grades depending on the thickness of the sheet used in the pipe. The three grades are as follows.


Thickness will differ for different type "A", "B" , and "C" GI pipe.

1. Light- Class A: The pipe is marked in yellow color for identification

2. Medium- Class B: The pipe is marked in blue color for identification.

3. Heavy - Class C . The pipe is marked in red color for identification.

 Therefore, Class A GI pipe is thinest GI pipe than other.

                                                                        GI Pipe

In the Compound Lighting Layout Plan drawing, It will note that all road crossing cable shall be laid in 150MM ( diameter) class "C" GI Duct. Since GI pipe can support the high stress, underground cable that cross road will laid inside GI pipe for protection of high press from heavy transport that pass through everyday.

http://jagvirgoyal.com/content/view/121/8/