BID Document for Guest House with Boundary Wall.pdf - Integrated ...

After placing a length of pipe in the trench the spigot end shall be centered in the socket and the pipe forced
home and aligned to gradient. The pipe shall be secured in place with approved back fill materials tamped on
both sides except at socket.
The socket end should face the upstream while laying the pipe line on ground.
Jointing of D.I. specials with the spigot end adopting the technique of Mechanical and push-on flange joint as
per procedure laid down in approved manufacturer’s specification / instructions using special type of D.I.
fittings conforming to I.S.: 13382-1992, suitable for Mechanical flexible joints may be used.
D.I. pipes may also be jointed by means of flanges as and where required and specified in the drawing or as
directed by the E.I.C.
The gasket used between flanges of pipes shall be of natural or synthetic rubber (Conforming to I.S.: 638 of
latest revision Edition) of thickness between 1.5 mm to 3 mm.
Each bolt should be tightened a little at a time taking care to tighten diametrically opposite bolts alternatively.
The practice of full tightening the bolts one after another is highly undesirable.
2.2.4 Anchor / Thrust Blocks
The contractor shall provide anchor / thrust blocks at all horizontal bends in case of 90°, 45° , 22½° & Tee
for 200 mm to 500 mm dia pipe and in case of 90°, 45° & Tee for 100 mm to 150 mm dia pipe to be placed
both below and above ground. Anchor blocks shall be in cement concrete as per dimensions given in the
approved drawings. The grade of concrete as specified in the relevant drawing shall be strictly followed.
Shuttering shall be as required and to the satisfaction of the Engineer-In-Charge.
The thrust faces of all blocks shall be placed directly against the undisturbed faces of excavations and the
shape and size of the blocks shall be as shown on the drawings or as otherwise determined by the Engineer-In-
Charge having regard to the nature of the ground and the load or thrust to be encountered. The concrete shall
be placed around the fitting in such a way that the coupling are not covered or fixed by it to allow for
flexibility and to provide access to the collars for replacing when necessary. Before casting concrete,
bituminous felt shall be wrapped around the fitting at the interface between concrete and fitting. Where
required, anchor clamps shall be cast into the anchor blocks.
2.2.5 Back Filling:
Back filling shall not be done until the pipe and appurtenances have the proper fit and the pipe is following the
ditch profile at the required depth that shall provide the required cover and has bed which allows the pipe to rest
smoothly and evenly.
Back-filling shall be done with excavated good earth as approved by the EIC.
3.0 Installation of Valves and Fittings
3.1 General:
Valves, fitting, plugs and caps shall be set and joined to pipes in the manner specified above for cleaning,
laying and joining pipes. The contractor shall furnish all components required for construction of valves
chambers and valves control access to buried valves. The valves shall be joined with dismantling pieces as
shown in the drawing to facilitate future maintenance.
3.2 Sluice Valves / Non Return Valves:
The valves shall be installed in accordance with IS: 2685. While installing the contractor shall ensure that all
grit and foreign matters are removed inside of the valves and all the faces are thoroughly cleaned and coated
with a thin layer of mineral grease, the sluice valves shall be installed with spindle vertical. The location of
valves shall be as per drawing. All sluice valves shall be installed on concrete bases. The length of the
operating stem shall properly adjusted depending upon the depth of the valve below operating level. This shall
be done to the satisfaction of the Engineer-In-Charge.
3.3 Air Valves:
Air valves shall be installed at high points using standard tee fittings as shown in the drawings or as directed
by the Engineer-In-Charge.
3.4 Washouts:
Washouts or scour valves shall be installed at low points as shown in the drawings or as directed by the
Engineer-In-Charge Washouts shall be installed by the standard T-piece with the main.
The outlet of the drain must be directed to the lowest ground level in such a way that no back flow to the main
pipe can occur.
The drain pipe of washouts shall not be connected to any sewer, submerged in any stream, or be installed in
all other manner that may permit back siphoning into the distribution system.
3.5 Easy Operation of Valves:
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