Fabricated PVC- U Fittings for Potable Water Supplies - Specification, Part 4: Specific Requirements for Caps
2009 Edition

This section defines the applicability of the standard to PVC-U caps used in potable water systems with pressure ratings of 0.6 MPa and higher. Caps designed for lower classes of 0.25 MPa and 0.4 MPa must be fabricated from pipes rated for 0.6 MPa or above. Detailed dimensions and minimum wall thicknesses are specified to maintain pressure resistance and structural integrity. Key parameters include the mean socket internal diameter (D), effective socket length (L), and minimum wall thickness (t), which is set at 90% of the corresponding pipe wall thickness and rounded to the nearest 0.1 mm. The section includes a comprehensive table listing minimum wall thickness values across nominal sizes and pressure classes.

This part lists the critical standards referenced, including IS 4985:2000 for unplasticized PVC pipes and IS 10124 Part 1 for the general requirements of fabricated PVC-U fittings. It prescribes the rounding method for numerical values according to IS 2:1960, maintaining consistent significant figures. The section reiterates dimensional requirements for caps, emphasizing adherence to specified tables and figures, and clarifies material and thickness parameters for various pressure classes.

Detailed manufacturing guidelines for PVC-U caps are provided, including definitions of critical dimensions such as D (mean socket internal diameter), L (effective minimum socket length), and t (minimum wall thickness). Caps must be produced from PVC pipes with solvent or rod welding techniques and may include fiberglass reinforcement. The minimum wall thickness is calculated as 90% of the pipe's wall thickness for the appropriate pressure class, rounded to the next 0.1 mm, as outlined in the provided thickness tables. This section also covers rounding rules and summarizes the essential manufacturing criteria.

This segment highlights the overarching requirements for materials, dimensions, testing, sampling, and conformity as established by IS 10124 Part 1. It underscores the use of PVC-U material, mandatory hydrostatic pressure testing, dimensional accuracy, and random batch sampling. The section includes information on size tolerances (typically ±0.5 mm for diameters) and marking mandates such as manufacturer identification, sizing, pressure class, and standard references. A pressure rating formula based on tensile strength, wall thickness, and diameter is also presented.

Key dimensional criteria for PVC-U caps are outlined, including the mean socket internal diameter (D), effective minimum socket length (L), and minimum wall thickness (t), which is fixed at 90% of the corresponding pipe thickness, rounded up to the nearest 0.1 mm. A detailed table provides minimum wall thickness values for various nominal sizes and pressure classes ranging from 0.6 MPa to 1.25 MPa. The section specifies that caps for 0.25 MPa and 0.4 MPa pressure classes are to be made from 0.6 MPa class pipes.

This section specifies the marking requirements for fabricated PVC-U caps, mandating clear and permanent inscriptions of the manufacturer’s name or identification mark, cap size, and pressure class as defined by IS 4985. Color coding conventions are detailed for quick identification of pressure categories: green for 0.6 MPa (Class 3), brown for 0.8 MPa (Class 4), yellow for 1.0 MPa (Class 4), and black for 1.25 MPa (Class 5). The use of the BIS Standard Mark is addressed, including licensing requirements regulated under the BIS Act, 1986.

An in-depth description of marking requirements reiterates the necessity of indelible markings featuring manufacturer identification, cap size, and pressure class. It restates the color coding scheme aligned with pressure ratings. The section also references dimensional and thickness standards and discusses the application of the BIS certification mark per regulatory provisions.

This subsection elaborates on the licensing and use of the Bureau of Indian Standards (BIS) certification mark on PVC-U fittings. It explains that manufacturers may display the Standard Mark only under a valid BIS license and provides guidance on obtaining manufacturer details and license conditions. The section reiterates key dimensional and thickness parameters linked to pressure classes and refers readers to contact BIS for official licensing and marking instructions.

Annex A offers typical illustrations and dimensional definitions of PVC-U caps according to IS 10124 Part 4. It defines key parameters such as mean socket internal diameter (D), effective minimum socket length (L), and minimum wall thickness (t). The annex emphasizes the requirement that caps for lower pressure classes (0.25 MPa and 0.4 MPa) be fabricated from 0.6 MPa pressure class pipes or higher. It includes a reference table summarizing minimum wall thickness values and summarizes marking and color coding standards.

This table presents the minimum wall thickness requirements for PVC-U caps across a range of nominal pipe sizes and working pressure classes from 0.6 MPa to 1.25 MPa. It reiterates key parameters including mean socket internal diameter (D), effective socket length (L), and wall thickness (t) calculated as 90% of the corresponding pipe wall thickness, rounded up to 0.1 mm. Notes clarify that caps for 0.25 MPa and 0.4 MPa classes must be produced from 0.6 MPa class pipes, and mention typical manufacturing methods like solvent welding and fiberglass reinforcement.