Unplasticized Non-Pressure Polyvinyl Chloride ( PVC -U ) Pipes for use in Underground Drainage and Sewerage Systems

IS 15328: Scope - Key Specifications & Tables

Scope: Covers dimensions, joint types, and performance criteria for PVC pipes and fittings with elastomeric sealing rings and solvent-cemented joints.

Key Tables (Clause 6.1.4)

1. Dimensions of Sockets & Spigot Ends for Solvent-Cemented Joints

• Note: Socket taper max 0°30'; manufacturer declares tapered or parallel design.

2. Dimensions of Elastomeric Sealing Ring Sockets and Spigot Ends

IS 15328 Key References: Dimensions & Specifications

1. Dimensions of Solvent-Cemented Joints (Table 4, Clause 6.1.4)

• Note: Socket taper max 0°30'. Manufacturer to specify tapered or parallel.

2. Dimensions of Elastomeric Sealing Ring Joints (Table 3, Clause 6.1.4)

• For da ≤ 200 mm: A min = 0.2 × d + 10 mm
• For da ≥ 250 mm: A min = 0.1 × d + 30 mm

3. Internal Negative Hydrostatic Pressure (Clause 10.2.2)

• Joints must withstand **

IS 15328 - Key Definitions, Symbols, and Specifications

1. Definitions (Clause 3.0 & 3.22.2)

• Acceptance Tests: Tests on samples from a lot to decide lot acceptance.

2. Key Symbols and Their Meaning

Note: Symbols A, B, C, H are illustrated in figures (refer to IS 15328).

3. Diameter Tolerances (Excerpt from Table 1)

Summary

• Use dn for nominal pipe size.
• Check dem,min and dem,max for mean diameter limits.
• Wall thickness varies between emin and emax.
• Dimension ratio DR = dn / emean is critical for design.
• Refer to Table 1 for diameter tolerance limits by nominal size

IS 15328 — Key Material Specifications & Formulas

1. Symbols & Definitions (Clause 3.22.2)

• dn: Nominal outside diameter
• de: Outside diameter at any point
• dan: Mean outside diameter
• dem,max / dem,min: Max / Min mean outside diameter
• d: Inside diameter of socket
• dsm: Mean inside diameter of socket
• DR: Dimension ratio = ( \frac{dn}{e} ) (wall thickness)
• e, emax, emin: Wall thickness (mean, max, min)
• l, H: Length parameters (engagement, lip, chamfer, etc.)

2. Wall Thickness & Diameter Tolerances (from tables)

3. Dimension Ratio (DR)

[ DR = \frac{dn}{e} ]

Where:

• (dn) = Nominal outside diameter
• (e) = Mean wall thickness

4. Acceptance Tests (Clause 3.22.2)

• Samples taken from a lot must conform to the dimensional tolerances above.
• Sampling and conformity criteria as per Table 15 (not fully provided here).

flowchart LR
    A[Nominal Diameter (dn)] --> B[Wall Thickness (e)]
    B --> C[Dimension Ratio (DR = dn/e)]
    A --> D[Mean Outside Diameter (dan)]
    D --> E[Max/Min Diameter Tolerances]
    B --> F[Max

IS 15328: Dimensions and Tolerances for Integral Sockets and Spigot Ends

Key Specifications (Clause 6.1.4 & Table 4)

• Socket dimensions: dym = mean outside diameter, A = minimum diameter, C = max length.
• Spigot end dimensions: l = minimum insertion length, H = chamfer height (approximate).

Tolerances (Clause 3.16)

• Tolerance = Permitted max value - Permitted min value.
• For solvent-cemented sockets, manufacturer must specify if socket is tapered (max taper 0°30') or parallel.
• For parallel sockets, mean diameter dym applies over entire socket length.
• Chamfer applied values are approximate.

Figures (for reference)

• Fig. 2-5: Illustrate dimensions, seal points, wall thickness, and measurement methods.

Summary

• Use Table 4 for dimensional checks.
• Confirm taper/parallel socket type.
• Apply tolerances per Clause 3.16.
• Refer to figures for measurement details and sealing points.

flowchart LR
A[Socket Dimensions] -->|Check dym, A, C| B[Table 4]
B --> C{Socket Type?}
C -->|Parallel| D[Apply dym over length]
C -->|Tapered| E[Max taper 0°30']
F[Spigot End] -->

IS 15328: Key Design & Construction Specifications

1. Dimensions for Joints

Solvent-Cemented Joints (Table 4, Clause 6.1.4)

• Note: Socket taper max 0°30'; mean outside diameter applies for parallel sockets.

Elastomeric Sealing Ring Joints (Table 3)

• For A min:
  • If da ≤ 200 mm: A min = 0.2 × d + 10 mm

IS 15328 Mechanical Characteristics - Key Specifications & Tables

1. Force Measurement (Clause 4.5)

• Force-measuring device accuracy: within ±2%.
• Force required to produce 1% to 4% deflection diametrically across the test specimen.

2. Testing Machine & Deflection Speed (Clause 4.1, Table 11)

• Compression testing machine must be constant-rate crosshead movement type.

3. Impact Testing (Clause B-4.1.2)

• Striker nose: hemispherical, polished steel, dimensions per Fig. 8 & Table 7.
• Striker mass & drop height (Table 8):

4. Internal Negative Hydrostatic Pressure (Clause 10.2.2)

• Joints withstand vacuum of 0.03 MPa (0.3 bar) for 15 min without leakage.

5. Dimensions of Elastomeric Sealing Rings (Table 3)

IS 15328 — Marking of Pipes: Key Specifications

• Marking Location & Frequency (Clause 12.1):

  • Mark at intervals ≤ 3 m, at least once per pipe.
  • Use ink/paint or hot embossing on a white base.
  • Marking must be legible without magnification.
  • Indentation marking allowed if wall thickness reduction ≤ 0.15 mm.

• Marking Content (Clause 12.2):
  Marking shall show:

  • Source of manufacture
  • Outside diameter
  • Stiffness class
  • Batch or Lot number

• Colour of Marking (Clause 12.3):

  • Marking colour must contrast with pipe's base colour for clear visibility.

• Optional Marking (Clause 12.4.1):

  • Standard Mark may be included.

Summary Table for Marking Requirements

flowchart LR
    A[Pipe] --> B{Marking at ≤3m intervals}
    B --> C[Ink/Paint or Hot Emboss]
    B --> D[Indentation ≤0.15 mm]
    C & D --> E[Marking Content]
    E --> F[Manufacturer ID]
    E --> G[Outside Diameter]
    E --> H[Stiffness Class]
    E --> I[Batch Number]
    E --> J[Optional: Standard Mark]
    E --> K[Colour contrasting pipe base]

This ensures traceability, quality control, and easy identification on-site.

IS 15328: Jointing and Assembly Key Specifications

1. Dimensions for Solvent-Cemented Joints (Table 4, Clause 6.1.4)

All dimensions in mm:

• Socket taper: max 0°30'.
• Manufacturer declares if socket is tapered or parallel.

2. Dimensions for Elastomeric Sealing Ring Joints (Table 3, Clause 6.1.4)

All dimensions in mm:

IS 15328: Testing Requirements Summary

Sampling & Conformity Criteria

• Sampling and conformity criteria are specified in Table 15 (Clause 1.7.2) and Table 14 (Clause 1.6.2).
• For type tests, 3 samples are tested as per Table 6 (Clause 2.1.1.2).

Test Specimens (Clause B-5)

• Length: 200 ± 10 mm, cut square and clean.
• For pipes > 40 mm diameter, draw equidistant lines as per Table 9:

• For pipes ≤ 40 mm, only one blow per specimen.

Impact Test Procedure (Clause B-6)

• Initial 25 blows minimum.
• Failures:
  • 0 failures: Pass.
  • ≥4 failures: Reject.
  • 1-3 failures: Continue testing until results fall into:
    • Region A: TIR ≤ specified limit → Accept.
    • Region C: TIR > specified limit → Reject.
    • Region B: Further testing needed.

Apparatus (Clause 4.1.4)

• Release mechanism with striker drop height adjustable up to 2 m ± 10 mm from specimen surface.

Quick Reference: Acceptance Criteria Flow

flowchart TD
    Start[Start Testing (25 blows)]
    NoFail[0 Failures?]
    Fail4Plus[≥4 Failures?]
    Fail1to3[1-3 Failures?]
    RegionA[Region A: TIR ≤ Specified]
    RegionB[Region B: Indeterminate]
    RegionC[Region C: TIR > Specified]
    DecisionAccept[Accept Batch]
    DecisionReject[Reject Batch]
    ContinueTest[Continue Testing]

    Start --> NoFail
    NoFail -- Yes --> DecisionAccept
    NoFail -- No --> Fail4Plus
    Fail4Plus -- Yes --> DecisionReject
    Fail

IS 15328: Sampling and Criteria for Conformity

Key Points from Clauses:

• Sampling & conformity procedures are per Tables 14 & 15 (Clauses 1.6.2, 1.7.2).
• Samples tested from each lot separately (Clause 1.3).
• Visual and dimensional sampling scale is detailed in Table 13 (F-1.5) (Clause 1.4.1).

Table 13: Sampling for Visual Appearance & Dimensional Requirements

Procedure Summary:

• Step 1: Take first sample size from lot.
• Step 2: If acceptance criteria met (≤ Ac), accept lot.
• Step 3: If rejection criteria met (≥ Re), reject lot.
• Step 4: Otherwise, take second sample and apply cumulative criteria.

Notes:

• Tables 14 & 15 (not provided here) specify sampling for other tests and criteria.
• This ensures quality control by statistically validating lot conformity.

flowchart TD
    A[Start

IS 15328: Packaging and Storage - Key Specifications & Tables

1. Conditioning Period (Clause 7.1, Table 10)

2. Test Specimens (Clause B-5, Table 9)

• Length: 200 ± 10 mm, ends square and clean.
• Number of equidistant lines on specimen depends on pipe diameter:

• Minimum 25 blows for initial impact test; acceptance/rejection based on failures.

3. Internal Negative Hydrostatic Pressure (Clause 10.2.2)

• Joints must withstand 0.03 MPa (0.3 bar) internal vacuum for 15 minutes without leakage.

4. Dimensions of Elastomeric Sealing Ring Sockets and Spigot Ends (Table 3)

IS 15328: Vicat Softening Temperature (VST) — Key Points

Definition (Clause 7.3, Annex A)

• VST: Temperature at which a standard indenter penetrates 1 mm into a PVC-U specimen under a load of 50 N ± 1 N.
• Temperature is raised uniformly during the test.
• Minimum acceptable VST: 79°C.

Test Setup (Clause 5.3, Annex A)

• Specimen mounted horizontally under the indenting tip.
• Indenter rests on the concave surface of the specimen.
• For wall thickness < 2.4 mm, indenter rests on the concave surface of the non-flattened segment, placed on a flattened segment.
• Indenter tip must be at least 3 mm from specimen edge.

Apparatus Components (Fig. 6)

• Dial gauge micrometer
• Interchangeable weight (to apply 50 N load)
• Load carrying plate
• Rod and indenting tip assembly
• Test specimen support
• Liquid bath for uniform heating

Summary of Procedure

flowchart LR
    A[Test Specimen] --> B[Indenting Tip]
    B --> C[Load of 50 N]
    C --> D[Penetration Measurement]
    D --> E[Temperature Raised Uniformly]
    E --> F[VST at 1 mm Penetration]

Note: Follow IS 15328 Annex A strictly for specimen preparation, apparatus calibration, and test conditions to ensure valid VST results.

IS 15328: Resistance to External Blows Test Method (at 0°C)

Key Points from IS 15328 Annex B (Clause 8.1)

• Purpose: Determine resistance of thermoplastic pipes (incl. unplasticized PVC) to external blows at 0°C.
• Applicability: Isolated production batches tested at 0°C.
• Sample Selection: Manufacturer supplies 3 pipe samples of different diameters/classes from a regular lot.

Sampling Plan (Table 15: Scale of Sampling for Resistance to External Blows)

• Interpretation:
  • Acceptance number = max allowed failures to accept the lot.
  • Rejection number = failures to reject the lot.
  • Test repeated if initial results are borderline.

Test Method Summary:

• Pipes are conditioned at 0°C.
• External blows applied (details per IS 15328 Annex B).
• Pipes pass if failures ≤ acceptance number.

Additional Notes:

• This is a type test per Clause 2.1.1.1.
• Manufacturer must provide samples from regular production.
• The test ensures pipe durability in cold conditions against impact.

flowchart LR
    A[Select Lot] --> B[Sample Pipes (3 diameters/classes)]
    B --> C[Condition at 0°C]
    C --> D[Apply External Blows]
    D --> E{Failures ≤ Acceptance Number?}
    E -- Yes --> F

IS 15328: Sampling Procedures Summary

Key Tables and Clauses

• Table 13 (Clause 1.4.1): Scale of Sampling for Visual & Dimensional Checks

• Random Sampling (Clause 1.4.2):
  Use a random number table (IS 4905) or systematic sampling by selecting every rth pipe, where
  [ r = \left\lfloor \frac{N}{n} \right\rfloor ]
  • N: Total pipes in lot
  • n: Sample size

Sampling Procedure

1. Identify lot size (N).
2. Determine sample size (n) from Table 13.
3. Select pipes randomly or systematically (every rth pipe).
4. Check acceptance/rejection criteria based on acceptance number.

flowchart TD
    A[Start: Identify Lot Size (N)] --> B[Determine Sample Size (n) from Table 13]
    B --> C[Calculate r = floor(N/n)]
    C --> D{Use Random Number Table?}