Pre-cast Conical Manhole is an innovation in the field of development of customized R. C. C. pre-cast Products. This product is exclusively manufactured for gainful utilization in the field of laying and jointing of underground cables for Power & Telecommunication industrial giants. These can be developed and manufactured as per the specific requirement of the costumer. The concrete used in casting various pieces of frustum of the cones is of M 30 Grade. The height, base and the top dimensions of the complete manhole can be worked out by increasing or decreasing the no of rings required to assemble the manhole. All the elemental rings of the manhole are provided the lifting hole to easily lift and place the rings on site. The wt. of each element is so designed that only 2-3 workers can manage to lift and assemble the manhole on site. The cost of this manhole is almost 2/3rd of the cost of the hand holes cast in setu. And time saving is quit eminent to any person. It is almost 1:20.
Technical Specifications :
Product: Pre-cast Concrete Conical Mahole
Height: 1950 mm (Max for 8/7 rings)
BaseDia: 1650 mm (Max for 8/7 rings)
Top Opening: 770 mm Std.
Height of each ring: 225 mm
Thickness of each ring: 50 mm Std
Materials: Manufactured by using M 30 Grade of Concrete mix
Re-enforcement: As per our Std. drawing
Load Bearing Capacity: Each manhole is tested for 30 tons of ultimate load to crash
Top Cover: Top cover is cladded with M S Plate galvanized to increase the life of the cover for multi use. The cover is provided with 2 Nos. of lifting bars to easily remove and place it
Procedure for Installation of Conical manholes
Location: The location of the manhole is received from the concerned Engineer with reference the requirement of the department.
Digging: After getting the location from the engineer the digging as per the size of the manhole is started. Taking care of the existing utilities under the ground, the final pit is prepared with the help of 4 workers only in 3-5 hrs depending upon the size of manhole and site conditions.
Assembly of the Manhole: After digging pit the cables to be passed through manhole are identified with the support of the concerned engineers and drawings. The PCC is then prepared using the standard aggregates and branded cement within 20 â€“ 30 minutes. Now starts the final assembly of the manhole. The base ring is placed on the PCC and the second ring is placed on the top of the base ring. These rings are easily handled by using the lifting holes in each element. Then the first outer ring is placed and then again the inner and outer rings are placed over each other to complete the manhole assembly. All the joints are the filled with cement mortar to avoid the water seepage inside the manhole. The cables identified to be placed in manholes are taken into the manhole through holes provided in the manholes and then sealed with cement.
Final Finishing: After the manhole is assembled the earth is refilled and compacted to the earth level. The inner surface of the manhole is again finished with the help of cement mortar. After the complete compaction the final tapering on the outer skirt of the manhole is done and the installation is now complete. The total time required to install on manhole is generally 5-7 hrs under standard conditions with the help of 4 workers only.
Reporting: After the installations the final report of the installation with respect to its location is sent to the client as per their standard formats.