Injection Moulded/Machined High-Density Polyethylene (HDPE) Fittings for Potable Water Supplies, Part 3: Specific Requirements for 90° TEES
2003 Edition

IS 8008 Part 3 does not directly specify distinct material grades for HDPE 90° tee fittings but refers to the general material requirements outlined in IS 8008 Part 1. These include guidelines on material manufacturing, grade classifications, and performance criteria. The fittings, sized 20 mm to 160 mm, are produced by injection moulding and machining from HDPE suitable for potable water use, conforming with IS 8008 Part 1 and compatible with HDPE pipes as per IS 4984.

Although IS 8008 Part 3 does not explicitly list dimensional tolerances within its clauses, it relies on the general tolerance guidelines presented in IS 8008 Part 1. Typical tolerances include diameter deviations of ±1% to ±2% of nominal size, wall thickness variation up to ±10%, and length tolerances around ±2 mm or based on manufacturing capabilities. These tolerances ensure consistent fit and function for tees ranging from 20 mm to 160 mm.

Every 90° tee fitting must be distinctly marked with the manufacturer's identification (name or trademark), the nominal size of the fitting, the material grade used, and the pressure rating class indicating its working pressure capacity. Additionally, the BIS Certification Mark may be applied if the manufacturer holds the appropriate BIS license. This marking ensures traceability, material conformity, and pressure rating transparency for quality assurance.

Yes, IS 8008 Part 3 encompasses both injection moulded and machined HDPE fittings intended for potable water supply systems. Fittings from 20 mm up to 315 mm diameter are primarily produced by injection moulding with machining applied as necessary, while larger sizes (355 mm and above) are typically machined from thick-walled extruded pipes or compression moulded slabs.

This standard ensures compatibility by specifying that 90° tee fittings are designed for welding connections to HDPE pipes compliant with IS 4984:1995. It mandates matching material properties, dimensions, and manufacturing processes (injection moulding and machining) that align with the thermal and mechanical characteristics of IS 4984 pipes. Standardized dimensional tolerances and pressure ratings further ensure seamless integration and leak-proof joints within potable water supply networks.