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

Scope of IS 8008 Part 3:

• Applies to dimensions, tolerances, and laying lengths of pipe fittings, specifically 90° tees.
• Final values (test/analysis) must be rounded per IS 2:1960 rules, retaining significant figures equal to specified values.
• Key dimensional tolerances:
  • Diameter for manufacturing reference, D: ± 2 mm
  • Weld length, K: ± 3 mm

Table 1: Dimensions for 90° Tees (Clause 3.2.2)

Notes:

• Laying length Z and tolerances are critical for proper fitting and welding.
• Referenced standards (e.g., IS 4984 for wall thickness) should be checked for complementary requirements.
• Always verify the latest editions of referenced standards for compliance.

This summary ensures correct dimensioning and tolerance adherence for 90° tees under IS 800

IS 8008 Part 3 (2003) Key References and Specifications

Referenced Parts of IS 8008 Series:

Table 1: Dimensions for 90° Tees (Clause 3.2.2)

Tolerances (Clause 122.5)

IS 8008 Part 3 — Manufacture of 90° Tees

Key Specifications (Clause 3.2 & 3.2.2)

• Manufacturing Method: Injection moulding for tees 20 mm to 160 mm diameter, with machining as required.
• Material & Quality: Per IS 8008 Part 1 (materials, tests, inspection).

Table 1: Dimensions for 90° Tees

Tolerances (Clause 122.5)

• Diameter for manufacturing reference, DI: ± 2 mm
• Weld length, K: ± 3 mm

Summary:
Use injection moulding for 20–160 mm tees, maintain laying length (Z) as per Table 1 with specified tolerances, and ensure weld length and diameter references conform to ±2 to ±3 mm tolerances.

flowchart LR
A[Injection Moulding] --> B[

IS 8008 Part 3: Injection Moulded 90° Tee - Key Points

1. Material & Manufacture

• Injection moulded 90° tees are manufactured for sizes 20 mm to 160 mm.
• Material, grade, and performance conform to IS 8008 Part 1.
• Machining is done as required for dimensional accuracy.

2. Typical Illustration (Fig. 1)

• Shows dimensions such as:
  • Diameter (D)
  • Branch diameter (d)
  • Wall thickness (t)
  • Radius of curvature (r)
• These ensure smooth flow and structural integrity.

3. Key Specifications

4. General Formula for Wall Thickness (t)

[ t = \frac{P \times D}{2 \times \sigma \times F} ] Where:

• (P) = Design pressure
• (D) = Diameter
• (\sigma) = Allowable stress of material
• (F) = Design factor

5. Inspection & Testing

• Follow IS 8008 Part 1 for sampling, testing (hydrostatic, dimensional checks), and inspection.

flowchart LR
    A[Injection Moulding] --> B[90° Tee]
    B --> C{Dimensions}
    C --> D[Diameter (D)]
    C --> E[Wall Thickness (t)]
    C --> F[Radius of Curvature (r)]
    B --> G[Machining (if required)]
    B --> H[Testing & Inspection]

Summary: IS 8008 Part 3 specifies injection moulded 90° tees for 20-160 mm diameters, manufactured per Part 1 material standards, with key dimensions ensuring performance and integrity.

IS 8008 Part 3: Laying Length and Tolerances for 90° Tees

Key Specifications (Clause 3.2.2 & 122.5)

Table 1: Dimensions for 90° Tees (All dimensions in mm)

Notes:

• Weld length (K) is kept constant at 15 mm for all sizes.
• Provisions exist for re-welding if welds are rejected.
• Wall thickness corresponds to IS 4984.

graph TD
A[Nominal Diameter] --> B[Diameter for Manufacturing Reference (D)]
B --> C[Weld Length (K) = 15 mm ± 3 mm]
C --> D[Laying Length (Z) with tolerance]

This concise

IS 8008 Part 3: Outside Diameter & Wall Thickness for Tees

• Reference: Clause 3.2.3 mandates that outside diameters and wall thicknesses of tees at ends (for welding) comply with IS 8008 Part 1, Clause 8.

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

• Tolerances (Clause 122.5):

• Wall Thickness: Must correspond to the pipe wall thickness as per IS 4984.

Summary:

• Use IS 8008 Part 1, Clause 8 for exact outside diameter and wall thickness specs.
• Follow Table 1 in Part 3 for manufacturing diameters and laying lengths

IS 8008 Part 3: Marking of 90° Tee Fittings

Key Marking Specifications (Clause 4.1 & 4.2)

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

• Manufacturer's identification
• Size of fitting (Nominal diameter)
• Material grade
• Class/working pressure rating
• BIS Standard Mark (optional, per Clause 4.2, subject to BIS licensing)

Dimensions & Laying Length (Clause 3.2.2, Table 1)

Notes:

• Laying length (Z) is critical for installation and must be within specified tolerances.
• Weld length (K) is fixed at 15 mm for all sizes.
• Marking ensures traceability and compliance with quality standards.

flowchart LR
    A[90° Tee Fitting] --> B{Marking}
   

Marking Details on 90° Tee Fittings as per IS 8008 Part 3

• Location: Marking shall be at a prominent place on the fitting (Clause 4.1).

• Mandatory Marking Information:

  • Source Identification: Manufacturer's name or trademark.
  • Size: Nominal size of the tee fitting.
  • Material Grade: Grade of the material used.
  • Class/Working Pressure: Pressure rating class corresponding to the fitting's working pressure.

• Optional Marking:

  • BIS Certification Mark: May be included to indicate compliance with Indian Standards (Clause 4.2).

Summary Table for Marking Information

Notes:

• The standard does not provide specific formulas or dimension tables for marking but refers to general marking requirements.
• Detailed dimensional and tolerance specifications are covered in other parts of IS 8008.
• Ensure markings are durable and legible after installation.

flowchart LR
    A[90° Tee Fitting] --> B[Marking Location: Prominent Place]
    B --> C{Marking Details}
    C --> D[Manufacturer ID]
    C --> E[Size]
    C --> F[Material Grade]
    C --> G[Class/Working Pressure]
    C --> H[BIS Mark (Optional)]

BIS Certification Marking (IS 8008 Part 3 - Clause 4.2.1)

• Governing Law: Use of BIS Standard Mark follows the Bureau of Indian Standards Act, 1986.
• Licensing: Manufacturers must obtain a license from BIS to use the Standard Mark.
• Copyright: BIS holds copyright on all publications; reproduction requires written permission, except for necessary details used in standard implementation.
• Marking Specification: Each 90° tee fitting shall bear the BIS Standard Mark.
• Contact for Licensing & Queries:

Summary Table: BIS Certification Marking Conditions

Key Notes:

• The Standard Mark ensures product conformity and quality.
• Licensing involves compliance with BIS rules and product testing.
• Marking on fittings confirms adherence to Indian Standards.

flowchart TD
    A[Manufacturer] -->|Applies for License| B[BIS]
    B -->|Grant License| C[Use Standard Mark]
    C --> D[Mark on Product (e.g., 90° Tee)]
    D --> E[Market Product with BIS Certification]

For detailed licensing procedures and mark specifications, contact the nearest BIS regional office.

IS 8008 Part 3: Dimensions and Tolerances for 90° Tees

Key Tolerances (Clause 122.5)

Dimensions for 90° Tees (Clause 3.2.2, Table 1)

Notes:

• Laying Length (Z) is the overall length of the tee.
• Wall thickness corresponds to IS 4984.
• Weld length (K) is constant at 15 mm for all sizes.

This table and tolerances ensure manufacturing consistency and fitment accuracy for 90° tees as per IS 8008 Part 3.

IS 8008 Part 3 does not explicitly list Performance Requirements formulas or tables for fittings like end caps or reducers. However, based on IS 8008 series and general engineering practice, key points include:

Performance Requirements (General Guidance)

• Design pressure and temperature must be adhered to as per the fitting type.
• Stress calculations follow standard pipe design formulas, considering hoop and longitudinal stresses.
• Material specifications and dimensional tolerances are critical for performance.
• Testing: Hydrostatic or pneumatic tests per IS standards to verify integrity.

Typical Stress Formulas for Fittings:

• Hoop stress, σ_h = (P × d) / (2 × t)
• Longitudinal stress, σ_l = (P × d) / (4 × t)

Where:

• P = internal pressure
• d = diameter
• t = thickness

Rounding Off Results:

• Follow IS 2:1960 for rounding test/analysis results, keeping significant figures consistent with specified values.

Reference Table Summary (IS 8008 Series):

For detailed performance specs, refer to the respective part of the series.

flowchart LR
    A[Fitting Type] --> B{Check Part in IS 8008}
    B -->|General| C[Part 1]
    B -->|90° Bend| D[Part 2]
    B -->|Reducer| E[Part 4]
    B -->|End Cap| F[Part 9]
    B -->|Others| G[Other Parts]

Summary: IS 8008 Part 3 lacks explicit performance formulas; use general pipe stress formulas and refer to appropriate parts for specific fittings.

IS 8008 Part 3: Testing and Inspection - Key Specifications

Rounding Off Results

• Final test/analysis values must be rounded as per IS 2:1960.
• Retain the same number of significant places as the specified standard value.

Laying Length & Dimensions for 90° Tees (Clause 3.2.2)

Tolerances on Dimensions (Clause 122.5)

Summary Notes:

• Ensure dimensional tolerances are strictly adhered to during inspection.
• Use specified laying lengths and weld lengths for 90° tees as per Table 1.
• Testing results must be rounded off per IS 2:1960 to maintain

Re-welding Provisions in IS 8008 Part 3

• Weld Length (K): Kept constant at 15 mm for all nominal diameters (20 to 160 mm).
• Tolerance on Weld Length: ± 3 mm (Clause 122.5).
• Diameter for Manufacturing Reference (D): Specified per nominal diameter with ± 2 mm tolerance.
• Laying Length (Z): Given per size with specific tolerances (±1 to ±3 mm).

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

Additional Notes:

• Outside diameters and wall thicknesses at weld ends must comply with IS 8008 (Part 1), Clause 8.
• Rejected welds should be re-welded maintaining the same weld length and tolerances to ensure uniformity.

Summary: For re-welding, maintain weld length **

IS 8008 Part 3: Compliance and Certification Key Points

1. BIS Certification Marking (Clause 4.2)

• Each 90° tee fitting may carry the BIS Standard Mark.
• The use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986.
• Manufacturers must obtain a licence from BIS to use the Standard Mark.
• The Standard Mark ensures conformity to quality and standardization requirements.

2. Rounding Off Rules

• Compliance test results must be rounded off as per IS 2:1960.
• The number of significant digits in the rounded value should match that of the specified value in the standard.

3. BIS Contact & Regional Offices

• For licensing and certification queries, contact the BIS regional offices listed in the standard (Delhi, Kolkata, Chandigarh, Chennai, Mumbai).
• BIS manages quality certification and copyright of standards.

Summary Table: BIS Certification Marking

flowchart TD
    A[Manufacturer] --> B[Apply for BIS Licence]
    B --> C{Licence Granted?}
    C -->|Yes| D[Use BIS Standard Mark on Product]
    C -->|No| E[Cannot use BIS Mark]
    D --> F[Product Certified as per IS 8008 Part 3]

Note: No specific formulas or tables for compliance tests are provided in this clause; refer to respective product or test clauses for detailed technical parameters.