Injection Moulded/Machined High-Density Polyethylene (HDPE) Fittings for Potable Water Supplies, Part 2: Specific Requirements for 90° Bends

IS 8008 Part 2: Scope & Key Specifications

This part covers specific requirements for 90° bends in HDPE pipes for potable water.

Key Dimensions for 90° Bends (All in mm)

Tolerances

• Diameter for manufacturing reference (DI): ± 2 mm
• Welding length (K): ± 3 mm

Additional Notes

• Rounding of values must comply with IS 2:1960 rules.
• The standard mark usage is governed by BIS Act, 1986.
• Refer to IS 8008 Part 1 for general requirements.

flowchart LR
    A[Nominal Diameter (D)] --> B[Diameter for Manufacturing Reference (DI)]
    B --> C[Welding Length (K)]
    C --> D[Laying Length (Z)]
    D --> E[90° Bend Fabrication]

This concise scope ensures proper dimensional control for 90° bends in HDPE potable water systems.

IS 8008 Part 2: Key References, Tables & Specifications

1. Reference Standard

• IS 8008 (Part 1): 2003 — Specifies general requirements for injection moulded/machined HDPE fittings for potable water.

2. Dimensions for 90° Bends (Clause 3.2.2)

• Tolerances:
  • Diameter for manufacturing reference (DI): ±2 mm
  • Welding length (K): ±3 mm

3. Certification & Marking

• Use of BIS Standard Mark governed by Bureau of Indian Standards Act, 1986.
• Licensing details available from BIS.

4. Rounding Off

• Follow IS 2:1960 for rounding off numerical values to maintain significant digits consistent with specified values.

Summary Diagram of 90° Bend Dimensions

graph LR
A[Nominal Diameter (D)] --> B[Diameter for Manufacturing Reference (DI)]

Manufacture Specifications from IS 8008 Part 2 (Clause 3.2)

• Material & Methods:

  • Conform to IS 8008 Part 1 for material, grade, sizes, testing, and inspection.
  • 90° bends (20 mm to 160 mm) are manufactured by injection moulding and machined if required.

• Key Dimensions for 90° Bends (Table 1, Clause 3.2.2):

• Tolerances:

  • Diameter for manufacturing reference (D): ± 2 mm
  • Welding length (K): ± 3 mm

• Certification & Marking:

  • Use of BIS Standard Mark follows BIS Act 1986 and related rules (Clause 4.2.1).

Summary Diagram of 90° Bend Dimensions

graph LR
A[Nominal Diameter (D)] --> B[Diameter for Manufacturing Reference (DI)]

IS 8008 Part 2: Manufacturing Methods - Key Points

• Material & Manufacture: As per Clause 3.1, all materials, grades, sizes, and performance requirements must conform to IS 8008 (Part 1): 2003.

• Manufacturing Method for 90° Bends:

  • Size range: 20 mm to 160 mm
  • Method: Injection moulding
  • Machining applied as required for finishing or dimensional accuracy.

• Reference Table 2 links to IS 8008 Part 1 for detailed specifications on:

  • Material properties (HDPE)
  • Testing methods
  • Sampling and inspection procedures

Summary Table: Manufacturing Method for 90° Bends

Notes:

• Injection moulding ensures uniformity and strength in bends.
• Machining improves dimensional accuracy and surface finish.
• Always verify with the latest edition of IS 8008 Part 1 for updated material and testing requirements.

flowchart LR
    A[Raw HDPE Material] --> B[Injection Moulding]
    B --> C[90° Bend Formation (20-160 mm)]
    C --> D{Machining Required?}
    D -- Yes --> E[Machining Process]
    D -- No --> F[Finished Product]
    E --> F

This diagram illustrates the manufacturing flow for 90° bends per IS 8008 Part 2.

IS 8008 Part 2: Injection Moulded 90° Bend Key Points

• Material & Manufacture: Injection moulded bends from 20 mm to 160 mm diameter, HDPE grade as per IS 8008 Part 1.
• Dimensions: Refer to Fig. 1 (Clause 3.2.1) for typical bend geometry—generally, the bend radius is 1.5 to 3 times the nominal diameter (D).
• Performance: Must meet pressure and leak-tightness tests as per Part 1.
• Machining: Allowed for precise fitting surfaces.

Typical Dimensional Table (Example)

Key Formula for Bend Radius:

[ R = k \times D ] where

• ( R ) = bend radius
• ( D ) = nominal diameter
• ( k ) = 1.5 to 3 (typical range)

flowchart LR
    A[Injection Moulded HDPE Pipe] --> B[90° Bend]
    B --> C{Bend Radius}
    C -->|1.5 × D| D[Minimum Radius]
    C -->|3 × D| E[Maximum Radius]
    B --> F[Machined Ends (if required)]

For exact dimensions and tolerances, always refer to IS 8008 Part 2 Fig. 1 and Part 1 specifications.

IS 8008 Part 2: Laying Length and Dimensions for 90° Bends

Key Dimensions (Table 1, Clause 3.2.2)

Tolerances

• Diameter for manufacturing reference (DI): ± 2 mm
• Welding length (K): ± 3 mm

Notes

• Laying length (Z) is the overall length of the bend including weld ends.
• Dimensions and tolerances ensure proper fit and welding quality.
• Refer to Fig. 1 (90° Bend) for dimensional illustration.

flowchart LR
    A[Nominal Diameter (D)] --> B[Diameter for Manufacturing Reference (DI)]
    B --> C[Welding Length (K)]
    C --> D[Laying Length (Z) ± Tolerance]
    D --> E[Installation & Welding]

This concise data is essential for manufacturing and installation of 90° bends as per IS 8008 Part

IS 8008 Part 2: Outside Diameter & Wall Thickness for Pipe Fittings

Key Points:

• Clause 3.2.3: Outside diameter and wall thickness of fitting ends must comply with Clause 8 of IS 8008 Part 1.
• Part 6 (2003): Specifies additional requirements for pipe ends (not detailed here).

Table: Dimensions for 90° Bends (Clause 3.2.2)

Tolerances:

• Diameter for manufacturing reference (D): ± 2 mm
• Welding length (K): ± 3 mm

Summary:

• Use IS 8008 Part 1 Clause 8 for exact outside diameter and wall thickness.
• Refer above table for 90° bend dimensions.
• Ensure tolerances are maintained for reliable fitment and welding.

flowchart LR
    A[Pipe Nominal Diameter] --> B[Check IS 8008 Part 1 Clause

IS 8008 Part 2: Marking Specifications for 90° Bend Fittings

Marking Requirements (Clause 4.1 & 4.2)

Each 90° bend fitting shall be clearly marked at a prominent place with:

• Source of manufacture (manufacturer's identification)
• Size of the fitting (Nominal Diameter)
• Grade of material
• Class (working pressure) corresponding to the pressure rating

Additionally, the fitting may bear the BIS Standard Mark as per Clause 4.2, governed by BIS Act 1986.

Dimensions & Tolerances for 90° Bends (Clause 3.2.2)

Tolerances

• Diameter for manufacturing reference (DI): ± 2 mm
• Welding length (K): ± 3 mm

Summary Diagram of Marking Elements

graph LR
A[90° Bend Fitting] --> B[Manufacturer ID]
A -->

Mandatory Marking Details as per IS 8008 Part 2 (Clause 4.1 & 4.2)

Each 90° bend fitting shall be clearly marked at a prominent place with:

• Identification of the manufacturer/source
• Size of the fitting (Nominal Diameter)
• Grade of material
• Appropriate class (working pressure) corresponding to the pressure rating

Additionally, each 90° bend fitting may carry the BIS Standard Mark as per Clause 4.2.

Key Table: Dimensions for 90° Bends (Clause 3.2.2)

Tolerances:

• Diameter for manufacturing reference, D: ± 2 mm
• Welding length, K: ± 3 mm

Summary Diagram of Marking Location on 90° Bend

flowchart LR
    A[90° Bend Fitting] --> B[Prominent Marking Location]
    B --> C{Marking Details}
    C --> D[Manufacturer Identification]
    C --> E[Size (Nominal Diameter)]
    C --> F[Material Grade]
    C --> G[Working Pressure Class]
    C --> H[BIS Standard Mark (optional)]

For licensing and use of the BIS Standard Mark, refer to the Bureau of Indian Standards Act, 1986 provisions.

BIS Certification Marking (IS 8008 Part 2: 2003)

• Clause 4.2: Each 90° bend fitting may be marked with the BIS Standard Mark.
• Clause 4.2.1: Use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986. Licensing details are available from BIS.

Key Dimensions for 90° Bend Fittings (Table 1, Clause 3.2.2)

• Tolerances:
  • Diameter for manufacturing reference (DI): ± 2 mm
  • Welding length (K): ± 3 mm

Notes:

• BIS mark indicates compliance with Indian Standards.
• Licensing and permission for use of the BIS mark must be obtained from BIS.
• Dimensions ensure interchangeability and quality control of fittings.

flowchart LR
    A[Manufacturer] --> B[Apply BIS Standard Mark]
    B --> C{License from BIS?}
    C -- Yes --> D[Mark fitting with BIS Mark]
    C -- No --> E[Cannot use BIS Mark]
    D --> F[Product meets IS 8008 Part 2]

For licensing, contact the BIS regional office nearest you (e.g., New Delhi, Kolkata, Chennai).

IS 8008 Part 2: Tables of Dimensions and Tolerances for 90° Bends

Key Table: Dimensions for 90° Bends (Clause 3.2.2)

Tolerances on Dimensions

• Diameter for manufacturing reference (DI): ± 2 mm
• Welding length (K): ± 3 mm

Notes:

• Laying length (Z) is critical for installation fit and includes specified tolerances.
• Welding length (K) is fixed at 15 mm for all sizes.
• Refer Fig. 1 in IS 8008 Part 2 for the 90° bend geometry.

Summary Diagram of 90° Bend Dimensions (Conceptual)

flowchart LR
    A[Nominal Diameter D] --> B[Diameter for Manufacturing Reference DI]
    B --> C[Welding Length K = 15 mm]
    C --> D[Laying Length Z ± tolerance]
    style A fill:#

IS 8008 Part 2: General Notes and Compliance Guidelines

Key Specifications:

• Dimensions for 90° Bends (Table 1)

  Nominal Diameter (D)	Diameter for Manufacturing Reference (DI)	Welding Length (K)	Laying Length (Z)
  20 to 160 mm	27 to 170 mm	15 mm (±3 mm)	35 to 170 mm (±1 to 3 mm)

• Tolerances:

  • Diameter (DI): ± 2 mm
  • Welding Length (K): ± 3 mm

Compliance Guidelines:

• Use BIS Standard Mark under Bureau of Indian Standards Act, 1986.
• Follow IS 2:1960 for rounding off numerical values; retain same significant figures as specified.
• Refer to IS 8008 Part 1 for general requirements of HDPE fittings.
• Always check for the latest edition of referenced standards.

Summary Diagram: Compliance Flow

flowchart TD
    A[Start: Design/Manufacture] --> B[Check IS 8008 Part 2 Dimensions]
    B --> C{Are Dimensions within Tolerances?}
    C -- Yes --> D[Apply BIS Standard Mark]
    C -- No --> E[Modify to Comply]
    D --> F[Round off values as per IS 2:1960]
    F --> G[Final Product Compliance]
    E --> B

Note: Always verify amendments and latest editions from BIS for updated compliance.