Pipes manufactured by The India Hume Pipe Co Ltd are in accordance with IS 458: 2003 and is used as non pressure pipe with NP1, NP2, NP3 and NP4 class.
Precast concrete pipes, popularly known as hume pipes were introduced in India by The India Hume Pipe Co Ltd as early as 1926. This pipe material, because of its inherent properties such as durability, strength, economy, etc. soon found acceptance and still enjoys the confidence of various government departments in their sewerage, irrigation and roadways projects.
These superior quality pipes are produced by the centrifugal spinning process discovered by Walter Hume of Australia and hence popularised as hume pipes.Manufacturing process
These pipes are manufactured in accordance with IS 458: 2003 and is used as non pressure pipe with NP1, NP2, NP3 and NP4 class based on the external load carrying capacity of the pipe. Hume/ RCC pipes are manufactured in diameter range from 80 mm to 2,600 mm. The standard length of the pipe is 2.5 m.
- Hume/RCC pipes offer a variety of joints
- Flush flexible rubber ring joint
- Socket spigot flexible rubber ring joint
- Rigid collar joint
The machinery and equipment used for the manufacture of hume pipe is characterised by an ability to handle and compact concrete which has low water content and rich in cement. The steel reinforcement is shaped into cages, using precision measures to fabricate a steel mesh by cage welding machines. The process adopted for manufacturing are:
- Centrifugal spinning in which the water/cement ratio of concrete is reduced by centrifugal action
- Centrifugal roller Suspension compaction method
- Vertical dry-cast methods using bi-directional rollers to compact the concrete.
Centrifugal spinning process is a conventional process. The water/cement ratio of concrete used in pipes is always less than 0.4. During Centrifugal process water get expelled and final water cement ratio in concrete is in the range of 0.3 to 0.32. This low water/cement ratios and high levels of compaction develop very high concrete compressive strengths up to 40 MPa and above.
In roller suspension process, cylindrical moulds with cast steel end rings are hung and rotated on a heavy shaft. Concrete is fed into the rotating mould and packed against its inside surface by a highly efficient combination of centrifugal force, rolling compression. Compression of very dry concrete (W/C ratio of about 0.28) by this method ensures strength.
In vertical casting process, the pipe is cast in vertical position. Concrete with consistency of earth moist is fed into annular space between the moulds. The concrete is compacted by a vibration core which is called internal core vibration system. Beside this, the pipe is pressed tightly by a hydraulic press which at same time forms the upper end of pipe, the spigot end.
The concrete thus produced by a is practically impermeable to water and has the highest level of durability. Performance tests carried out by the manufacturers to demonstrate compliance of finished Hume pipe are:-
- External load testing
- Hydrostatic Testing
- Water absorption
- Measurement of concrete cover to reinforcement
- Measurement of dimensions other than concrete cover
Advantages of hume / RCC pipe
- High compressive strength
- High external load carrying capacity
- Impermeable property of concrete
- Autogenous healing of minor cracks
- Fast and simple installation
- Service life of around 100 years
Application of hume/ RCC pipes
Hume pipes/reinforced cement concrete (RCC) are generally used for stormwater drain, sewerage, road culverts, irrigation and railway culverts. The other allied applications of hume/RCC pipes are septic tanks, water tanks, cattle troughs, vent shaft and spun poles. For carrying highly acidic sewage or industrial effluent waste, additional lining/ coating can be provided to resist chemical attack and corrosion.Present and future of concrete pipe industry
The industry which started in 1926 progressed very fast in India and now there are lot of hume/ RCC pipe manufacturers from organised and unorganised sectors spread over the length and breadth of country.
The Indian Hume Pipe Company Ltd has specialisation in hume pipe manufacturing of larger diameter hume pipes in the range of 900 mm to 2,600 mm and executing sewerage projects for Major Cities and big Municipal Corporations like Hyderabad Metropolitan Water supply and Sewerage Board (HMWSSB) and Bangalore Water Supply and Sewerage Board (BWSSB).Conclusion
Pipeline is an integral part of modern life. Hume Pipes takes away polluted water to a safe place. It will continue to be the most appropriate material for India for a long time to come.
The continuous improvement in making concrete pipe made the product more reliable. Decades of research and development of many aspects of concrete pipe has enabled concrete pipe producers to implement that can withstand a complete range of underground environments and effluent profiles.
This application of a sound asset management approach to public infrastructure reinforces the choice of concrete pipe for sustainable storm water drainage systems under Swachh Bharat Abhiyan of Govt. of India.
Modern man cannot live without adequate sanitary sewers, storm sewers, and culverts. A drainage pipeline built today with low-maintenance RCC/ Hume pipes would last for over 100 years, if the system is planned and designed with full knowledge of existing and future effluent characteristics and loading.AUTHOR:
Shashank Shah, General Manager, The Indian Hume Pipe Co Ltd