Frequently asked questions
What is HDPE ?
HDPE stands for High Density PolyEthylene. It’s a polymer produced from crude oil and is used for manufacturing plastic bottles, containers, pipes, etc.
Can HDPE items be recycled ?
HDPE pipes, containers, bottles, etc can be recycled, although recycled HDPE is prohibited for use in manufacturing pipes for drinking water supply or any other items which is related to storing food or any other items for direct consumption by humans.
What’s the use of HDPE Pipes ?
HDPE pipes are used for transporting cold potable drinking water, sewerage distribution, Gas distribution, etc.
What are the standards for HDPE Pipe ?
HDPE Pipes are manufactured in India as per standards / specifications approved by the Bureau of Indian Standards, while in other countries different standards are used, Like many countries follow ISO standards, Britain follows BS-EN standards, USA follows AWWA standards, etc.
Some of the standards applicable for manufacturing HDPE Pipes are as follows:
- HDPE Pipes for Drinking water: IS 4984:2016, ISO 4427, etc.
- HDPE Pipes for Sewerage: IS 14333:1996, etc.
- HDPE Pipes for Gas Distribution: IS 14885:2001, ISO 4437, etc.
- HDPE Pipes for Irrigation: IS 12786:1989
What is the material Grade for HDPE Pipes ?
HDPE Pipes are manufactured by resins of Grade PE 63 or PE 80 or PE 100. These different grades of resins have the following characteristics.
Minimum Required Strength (Mpa)
PE 100, Minimum Required Strength of 10 MPa, Design Stress of 8 MPa
PE 80, Minimum Required Strength (Mpa) of 8 MPa, Design Stress of 6.3 MPa
PE 63, Minimum Required Strength of 6.3 MPa, Design Stress of 5 MPa
Due to these, HDPE pipes manufactured from these resins have the wall thickness in the following order for the same PN rating:
Wall thickness of pipe manufactured from PE 63 > PE 80 > PE 100
In simple terms, it means that to withstand a particular water pressure, Pipe manufactured from PE 100 resin is less thick (and hence lower weight) than the pipe manufactured from PE 80 and similarly Pipe manufactured from PE 80 resin is less thick than the pipe manufactured from PE 63 resin.
What does SDR in context of HDPE Pipes mean ?
SDR stands for Standard Dimension Ratio. It’s the ratio of the nominal outside diameter of a pipe to its nominal wall thickness.
What is pipe series ?
ipe series, designated by ‘S’, is derived by the following formula: S = (SDR – 1) / 2
What does PN rating in HDPE Pipes mean ?
For plastic piping systems conveying water, it corresponds to the maximum continuous operating pressure, expressed in bar, which can be sustained with water at 20 °C, based on the minimum design coefficient.
Can HDPE Pipes be manufactured from recycled / reprocessed material ?
HDPE Pipes can be manufactured from recycled / reprocessed material but they cannot be used for drinking water supply. ISO 4427 clearly states that
“Clean, reprocessable material generated from a manufacturer's own production and works testing of products according to ISO 4427 may be used if it is derived from the same compound as used for the relevant production. Reprocessable material obtained from external sources and recyclable material shall not be used.”
What’s the difference between IS 4984:1995 & IS 4984:2016 ?
From 1 May 2018, BIS has withdrawn IS 4984:1995 and has replaced it with IS 4984:2016. HDPE Pipes manufactured and tested after 30 April 2018 are to abide by the specifications and norms mentioned in IS 4984:2016. Manufacturers are not allowed to use ISI mark on pipes manufactured as per IS 4984:1995 from 1 May 2018 onwards. IS 4984:2016 has introduced some additional test and stringent norms to ensure better quality of HDPE Pipes. The wall thickness for HDPE Pipes has also changed in IS 4984:2016.
What is DI Pipe?
Ductile iron pipe is a pipe made of ductile cast iron commonly used for potable water transmission and distribution. This type of pipe is a direct development of earlier cast iron pipe, which it has superseded.
How long does ductile iron pipe last?
An expected lifespan of 100 years is likely for ductile iron pipe, based on test results, field inspections and in-service operations over 50 years.
What are Benefits of Ductile Iron Pipe?
What is k7 DI pipes?
DI pipe K7 means, 7 is the pressure class of the DI pipe and 7 represents the pipe's internal pressure withstanding capacity. ... DI K7 pipes specifications would vary and this would be based on the basic dimension and the thickness of the ductile iron pipes.