Fabricated PVC-U Fittings for Potable Water Supplies - Specification, Part 1: General Requirements

IS 10124 Part 1: Scope & Key Specifications

• Scope: Specifies dimensions and testing criteria for PVC pipes and fittings with socket joints, including elastomeric sealing ring joints.

Key Formulas for Socket Dimensions (Fig. 1)

[ D_2 = D - L \tan \frac{a}{2} ] [ D_1 = D + L \tan \frac{a}{2} ]

Where:

• (D) = diameter at mid-point of socket length
• (D_1) = diameter at mouth
• (D_2) = diameter at root
• (L) = socket length
• (a) = total included angle of taper

Important Tables Summary

Sampling & Acceptance (Table 3 excerpt)

Notes

• Dimensions in mm.
• Rounding off per IS 2:1960.
• Certification marking governed by BIS Act, 1986.

flowchart LR
    A[Nominal Size] --> B[Socket Length (L)]
    B --> C[Diameter at Mid-point (D)]
    C --> D[Diameter at Root (D2)]
    C --> E[Diameter at Mouth (D1)]
    D & E --> F[Socket Geometry]

This summary helps in design, manufacturing, and quality control of PVC socket fittings as per IS 10124 Part

IS 10124 Part 1: Key References, Formulas, and Tables

1. References (Table 2)

2. Socket Dimension Formulas (Fig. 1)

• ( D_2 = D - L \tan(\alpha/2) )
• ( D_1 = D + L \tan(\alpha/2) )

Where:

• (D) = diameter at midpoint of socket length
• (L) = socket length
• (\alpha) = total included taper angle

3. Socket Dimensions (Table 1)

4. Socket for Elastomeric Sealing Ring Joint (Table 2)

5. Sampling and Permissible Defectives (Table 3)

| Lot Size (No. of fittings) | Sample Size | Acceptance Number A | Acceptance Number

IS 10124 (Part 1): 2009 — Terminology & Key Formulas

Key Terms (Fig. 1 & 2)

• D = Diameter at mid-point of socket length
• D₁ = Diameter at mouth of socket
• D₂ = Diameter at root of socket
• L = Socket length
• a = Total included angle of taper
• m = Minimum depth of engagement (for elastomeric sealing ring joints)
• dim = Mean socket internal diameter at mid-point of depth of engagement

Important Formulas for Socket Diameters:

[ D_2 = D - L \tan \frac{a}{2} ] [ D_1 = D + L \tan \frac{a}{2} ]

Tables Summary:

(Refer Table 1 for full sizes)

(Refer Table 2 for full sizes)

Sampling & Acceptance (Table 3)

• Sample size and permissible defectives depend on lot size.
• For example, lot size 501-1000 fittings: sample 13, acceptance number A=1, B=0.

Note: All dimensions in mm. Use IS 2:1960 for rounding off values.

flowchart LR

IS 10124 Part 1 – Size of Fitting: Key Points

• Fitting sizes correspond to the nominal pipe diameters per IS 4985, ranging from 20 mm to 630 mm.
• The mean inside diameter at the socket midpoint must comply with limits in Table 1 (not provided here, but essential for design).
• Mean inside diameter = arithmetic mean of two diameters measured 90° apart at the socket midpoint.
• Socket taper angle limits:
  • For 63 to 75 mm pipes: max included taper angle = 0° 40'
  • For 90 mm and above pipes: max included taper angle = 0° 30'
• Socket length is a minimum dimension; manufacturers determine exact midpoint for measurements.

Practical Notes:

• Only manufacturers have tooling to accurately measure socket inside diameters.
• Variations exist between manufacturers; hence, fitting dimensions are controlled by standards and manufacturer specs.

Summary Table (conceptual):

flowchart TD
    A[Pipe Nominal Diameter (IS 4985)] --> B[Select Fitting Size (IS 10124)]
    B --> C[Measure Socket Inside Diameter]
    C --> D{Within Tolerance?}
    D -- Yes --> E[Use Fitting]
    D -- No --> F[Reject or Adjust]
    B --> G[Check Socket Taper Angle]
    G --> D

For detailed dimensional values, refer to Table 1 of IS 10124 Part 1.

IS 10124 Part 1: Dimensions of Socket - Key Details

1. Socket Inside Diameter (Clause 5.1.2)

• Mean inside diameter at mid-point of socket depth = average of two diameters measured at 90° to each other.
• Taper limits:
  • Pipe sizes 63–75 mm: max total included taper angle = 0° 40'
  • Pipe sizes ≥ 90 mm: max total included taper angle = 0° 30'
• Refer Table 1 (not provided here) for max/min mean inside diameter values.

2. Minimum Socket Length (Clause 5.1)

• Socket length ( L ) is given by:

[ L = 1.5 \times D ]

where:

• ( L ) = minimum socket length
• ( D ) = nominal inside diameter of fitting (matching pipe OD per IS 4985)

3. Out-of-Roundness Tolerance (Clause 5.1.3)

• Max out-of-roundness = max diameter - min diameter =

[ \max(0.007 \times D, 0.2 \text{ mm}) ]

• Note: Not applicable for fittings with pressure ratings 0.25, 0.4, 0.6 MPa (Classes 1, 2, 3).

Summary Table (Example)

flowchart LR
    A[Socket Length L] -->|L = 1.5 × D

IS 10124 Part 1 (2009) - Tests and Performance Requirements Summary

1. Socket Dimensions for Elastomeric Sealing Ring Joint

• Refer Table 2 & Fig. 2 for key dimensions:
  • Minimum Depth of Engagement (m)
  • Mean Socket Internal Diameter at Mid-Point (dim)
• Formula for socket diameters (Fig. 1):
  [ D_2 = D - L \tan \frac{\alpha}{2}; \quad D_1 = D + L \tan \frac{\alpha}{2} ]
  Where:
  • (D) = diameter at mid-point of socket length
  • (L) = socket length
  • (\alpha) = total included taper angle

2. Sampling & Acceptance Criteria (Table 3, Clause 7.2.2)

3. Short Term Hydraulic Test (Annex A, Clause 6.2)

• Specimens tested after 24h setting.
• On failure, retest after at least 10 days setting.
• Must meet performance criteria in Clause 6.2.

4. Certification Marking (Clause 8.2.1)

• Use of BIS Standard Mark governed by BIS Act, 1986.
• Licensing conditions available from BIS.

Key Points

• Dimensions critical for sealing performance.
• Sampling plan ensures quality control.
• Hydraulic test validates joint integrity.
• BIS certification ensures compliance.

flowchart TD
    A[Manufacture] --> B[Sampling per Table 3]
    B -->

IS 10124 Part 1: Production Routine Test - Key Points

Clause 7.2: Production Routine Test

• Spot tests during manufacture to verify quality of a lot.
• Methods per Clauses 5 (Dimensions) and 6.2 (Short Term Hydraulic Test).

Important Formulas (Socket Dimensions)

Given:

• (D) = diameter at mid-point of socket length
• (D_1) = diameter at mouth
• (D_2) = diameter at root
• (L) = socket length
• (a) = total included taper angle

[ D_2 = D - L \tan \frac{a}{2} ] [ D_1 = D + L \tan \frac{a}{2} ]

Table 3: Sampling & Permissible Defectives for Production Routine Test

Short Term Hydraulic Test (Clause 6.2 & Annex A)

• Conducted on samples from the lot.
• Ensures fittings withstand specified pressure without leakage or failure.
• Test pressure and duration as per product specifications.

Summary:

• Use Table 3 for sampling size and defect acceptance.
• Verify socket dimensions using formulas and Tables 1 &

IS 10124 Part 1 - Marking (Clause 8.1 & 8.2)

Key Marking Requirements:

• Markings must be clear, indelible, and visible after installation.
• Mark to include:
  • Manufacturer's name or ID
  • Size of fitting and class (working pressure) per IS 4985
  • Degree of bend for fabricated bends
  • Colour coding for class identification:

BIS Certification Marking (Clause 8.2):

• Optional Standard Mark usage governed by BIS Act 1986.
• Manufacturer must obtain a license for the Standard Mark.

Additional Notes:

• Marking ensures traceability and correct application based on pressure class.
• Colour coding aids quick visual identification on-site.

flowchart TD
    A[Marking on Fitting] --> B[Manufacturer's Name/ID]
    A --> C[Size & Class]
    A --> D[Degree of Bend (if applicable)]
    A --> E[Colour Coding]
    E --> F[Red (Class 1)]
    E --> G[Blue (Class 2)]
    E --> H[Green (Class 3)]
    E --> I[Brown (Class 4)]
    E --> J[Yellow (Class 5)]
    E --> K[Black (Class 6)]
    E --> L[Pink (Plumbing)]

This concise marking system ensures compliance and safety in pipe fitting applications as per IS 10124 Part 1.

Short Term Hydraulic Test - IS 10124 (Part 1): 2009 (Annex A, Clause 6.2)

Key Specifications:

• Test Pressure: Minimum 4.19 times the working pressure.
• Test Duration: At least 1 hour.
• Test Equipment: Must apply internal hydraulic pressure as above.
• Test Specimen:
  • Fitting solvent welded to a pipe section.
  • Pipe length minimum 250 mm.
  • Pipe must withstand at least 4.19 times the working pressure.
• Setting Time: Allow 24 hours for joint setting before testing.

Summary Table: Short Term Hydraulic Test Conditions

This ensures the fitting and joint integrity under high pressure simulating short-term service conditions.

IS 10124 Part 1: Specific Requirements for Various PVC-U Fittings

Key Formulas for Socket Dimensions

• Given:
  • D = diameter at mid-point of socket length
  • L = socket length
  • O = total included angle of taper
• Calculate diameters at socket ends:
  [ D_2 = D - L \tan \frac{O}{2} \quad \text{and} \quad D_1 = D + L \tan \frac{O}{2} ]

Important Tables

Table 1: Socket Dimensions (mm)

(Full table covers 20 to 630 mm sizes.)

Table 2: Socket Dimensions for Elastomeric Sealing Ring Joint (mm)

Sampling & Quality Control (Clause 7.2.2)