Unplasticized Non-Pressure Polyvinyl Chloride ( PVC -U ) Pipes for use in Underground Drainage and Sewerage Systems
2003 Edition

Overview of Scope - IS PVC-U Pipes

Coverage: Defines dimensional parameters, joint types, and performance criteria for PVC-U pipes and fittings incorporating elastomeric seals and solvent cement joints.

Essential Dimension Tables (Clause 6.1.4)

1. Solvent-Cemented Joint Dimensions

• Note: Maximum socket taper is 0°30'; manufacturers specify if tapered or parallel.

2. Elastomeric Seal Ring Joint Dimensions

Key Dimensions and References in IS 15328

1. Solvent Cement Joint Dimensions (Table 4, Clause 6.1.4)

• Socket taper limited to max 0°30'. Manufacturer specifies tapered or parallel design.

2. Elastomeric Sealing Ring Dimensions (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 resist a vacuum of 0.03 MPa (0.3 bar) for 15 minutes without leakage.

Definitions and Symbols per IS 15328

1. Definitions (Clause 3.0 & 3.22.2)

• Acceptance Tests: Evaluations on sample pipes from a batch to determine batch acceptance.

2. Common Symbols and Definitions

Note: Symbols A, B, C, H correspond to specific dimensions shown in IS 15328 diagrams.

3. Diameter Tolerances (From Table 1)

Summary

• Use dn as nominal pipe size.
• Verify mean diameter within dem,min and dem,max.
• Wall thickness fluctuates between emin and emax.
• Dimension ratio calculated as DR = dn / emean.
• Refer to Table 1 for tolerance limits based on nominal diameter.

Material Parameters and Dimensional Criteria per IS 15328

1. Symbols & Definitions (Clause 3.22.2)

• dn: Nominal external diameter
• de: External diameter at any point
• dan: Average external diameter
• dem,max / dem,min: Maximum / Minimum average external diameter
• d: Internal diameter of socket
• dsm: Average internal diameter of socket
• DR: Dimension ratio calculated as ( \frac{dn}{e} ) (wall thickness)
• e, emax, emin: Wall thickness (average, maximum, minimum)
• l, H: Length parameters (engagement length, chamfer, etc.)

2. Wall Thickness and Diameter Tolerances

3. Dimension Ratio (DR)

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

• (dn): Nominal outside diameter
• (e): Average wall thickness

4. Acceptance Testing (Clause 3.22.2)

• Samples from production lots must comply with dimensional tolerances.
• Sampling and acceptance criteria outlined in Table 15 (not fully included here).

flowchart LR
    dn[Nominal Diameter] --> e[Wall Thickness]
    e --> DR[Dimension Ratio (DR = dn/e)]
    dn --> dan[Average OD]
    dan --> tol[Max/Min Diameter Tolerances]
    e --> maxmin[Max/Min Wall Thickness]

Dimensions and Tolerance Requirements for Integral Sockets and Spigots per IS 15328

Essential Dimensions (Clause 6.1.4 & Table 4)

• Socket dimensions: dym refers to mean outside diameter; A is minimum diameter; C is maximum socket length.
• Spigot end dimensions: l is minimum insertion length; H is approximate chamfer height.

Tolerances (Clause 3.16)

• Tolerances represent allowable maximum minus minimum values.
• Manufacturer must specify whether the solvent-cemented socket is tapered (max 0°30') or parallel.
• For parallel sockets, the mean diameter dym applies over the full socket length.
• Chamfer dimensions are approximate.

Illustrations

• Figures 2 to 5 demonstrate dimensions, sealing points, wall thickness measurement, and other relevant details.

Summary

• Verify dimensions using Table 4.
• Confirm socket taper or parallel type.
• Apply tolerances as per Clause 3.16.
• Refer to figures for measurement and sealing details.

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

Design and Installation Requirements per IS 15328

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

• Maximum taper of socket is 0°30'. For parallel sockets, mean outside diameter is applicable.

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

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

Mechanical Properties and Testing Procedures in IS 15328

1. Force Measurement Accuracy (Clause 4.5)

• Force measuring devices must have an accuracy within ±2%.
• Forces applied correspond to 1% to 4% diameter deflection during testing.

2. Test Machine and Deflection Rate (Clause 4.1, Table 11)

• Constant rate crosshead movement compression machines are required.

3. Impact Testing (Clause B-4.1.2)

• Striker is a hemispherical polished steel nose as per Fig. 8 and Table 7.
• Mass and drop height per Table 8:

4. Internal Negative Hydrostatic Pressure Test (Clause 10.2.2)

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

5. Elastomeric Seal Ring Dimensions (Table 3)

Marking Specifications for PVC-U Pipes per IS 15328

• Marking Frequency and Location (Clause 12.1):

  • Markings must appear at intervals not exceeding 3 m, with at least one marking per pipe.
  • Ink, paint, or hot embossing on a white background is acceptable.
  • Markings should be clear and readable without magnifying aids.
  • Indentations are permitted if wall thickness reduction does not exceed 0.15 mm.

• Marking Details (Clause 12.2):

  • Manufacturer's identification
  • Outside diameter
  • Stiffness classification
  • Batch or lot number

• Marking Color (Clause 12.3):

  • Must contrast with pipe color for easy visibility.

• Optional Marking (Clause 12.4.1):

  • BIS Standard Mark may be included if applicable.

Marking Summary Table

flowchart LR
    Pipe --> MarkingInterval{Mark every ≤3 m}
    MarkingInterval --> InkOrEmboss[Ink, Paint or Hot Emboss]
    MarkingInterval --> Indentation[Indentation ≤ 0.15 mm]
    InkOrEmboss & Indentation --> MarkingContent[Marking Content]
    MarkingContent --> ManufacturerID
    MarkingContent --> OutsideDiameter
    MarkingContent --> StiffnessClass
    MarkingContent --> BatchNumber
    MarkingContent --> OptionalBISMark
    MarkingContent --> ColorContrast

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

Jointing and Assembly Guidelines per IS 15328

1. Solvent Cemented Joint Dimensions (Table 4, Clause 6.1.4)

• Maximum taper allowed is 0°30'. Manufacturer specifies tapered or parallel socket.

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

Summary of Testing Requirements per IS 15328

Sampling and Conformance

• Sampling and acceptance criteria outlined in Table 15 (Clause 1.7.2) and Table 14 (Clause 1.6.2).
• Type tests require 3 samples as per Table 6 (Clause 2.1.1.2).

Test Specimens (Clause B-5)

• Specimens cut to length of 200 ± 10 mm with square, clean ends.
• For pipes > 40 mm diameter, equidistant lines are marked as per Table 9:

• Pipes ≤ 40 mm diameter receive only one blow per specimen.

Impact Test Procedure (Clause B-6)

• Initial minimum of 25 blows applied.
• Acceptance criteria:
  • 0 failures: pass
  • ≥ 4 failures: reject
  • 1 to 3 failures: further testing to classify in regions A, B, or C based on total impact resistance.

Equipment (Clause 4.1.4)

• Release mechanism with adjustable striker drop height of 2 m ± 10 mm.

Acceptance Decision Flow

flowchart TD
    Start[Impact Test Start (25 Blows)]
    NoFail[Are there 0 Failures?]
    Fail4Plus[Are Failures ≥ 4?]
    Fail1to3[Are Failures between 1 and 3?]
    RegionA[Region A: TIR ≤ Specified Limit]
    RegionB[Region B: Indeterminate]
    RegionC[Region C: TIR > Specified Limit]
    Accept[Accept Batch]
    Reject[Reject Batch]
    Continue[Continue Testing]

    Start --> NoFail
    NoFail -- Yes --> Accept
    NoFail -- No --> Fail4Plus
    Fail4Plus -- Yes --> Reject
    Fail4Plus -- No --> Fail1to3
    Fail1to3 -- Yes --> Continue
    Continue --> RegionA
    Continue --> RegionB
    Continue --> RegionC
    RegionA --> Accept
    RegionC --> Reject
    RegionB --> Continue

Sampling and Acceptance Criteria Overview per IS 15328

Important Clauses

• Sampling and acceptance procedures follow Tables 14 & 15 (Clauses 1.6.2 and 1.7.2).
• Samples are drawn from each production lot separately (Clause 1.3).
• Visual and dimensional sampling is detailed in Table 13 (F-1.5) (Clause 1.4.1).

Table 13: Sampling for Visual and Dimensional Inspection

Sampling Procedure

1. Identify the lot size.
2. Determine sample size from Table 13.
3. Select samples randomly or systematically (every rth pipe, where r = floor(N/n)).
4. Accept or reject based on acceptance/rejection numbers.

Notes

• Tables 14 & 15 specify sampling for other tests.
• This method ensures quality control via statistical validation.

flowchart TD
    Start[Identify Lot Size (N)] --> SampleSize[Determine Sample Size (n)]
    SampleSize --> CalculateR[Calculate r = floor(N/n)]
    CalculateR --> RandomSelection{Use Random Number Table?}
    RandomSelection -- Yes --> SelectSamplesRandomly
    RandomSelection -- No --> SelectSamplesSystematically
    SelectSamplesRandomly --> InspectSamples
    SelectSamplesSystematically --> InspectSamples
    InspectSamples --> Decision{Accept or Reject}

Packaging and Storage Guidelines per IS 15328

1. Conditioning Period (Clause 7.1, Table 10)

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

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

• Minimum 25 blows for initial impact testing; acceptance based on failure count.

3. Internal Negative Hydrostatic Pressure Test (Clause 10.2.2)

• Joints must endure internal vacuum of 0.03 MPa (0.3 bar) for 15 minutes leak-free.

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

Determining Vicat Softening Temperature (VST) per IS 15328 Annex A

Definition (Clause 7.3, Annex A)

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

Test Setup (Clause 5.3, Annex A)

• Specimen positioned horizontally below the indenter.
• Indenter rests on the concave surface of the specimen.
• For wall thickness less than 2.4 mm, the indenter rests on the concave side of a non-flattened segment placed upon a flattened segment.
• Indenter tip must be at least 3 mm away from specimen edge.

Test Apparatus Components (Fig. 6)

• Dial gauge micrometer
• Interchangeable weights to apply 50 N load
• Load distributing plate
• Rod and indenting tip assembly
• Specimen support
• Heated liquid bath for uniform temperature increase

Procedure Summary

flowchart LR
    Specimen --> Indenter
    Indenter --> Load[Apply 50 N Load]
    Load --> Heat[Uniform Temperature Increase]
    Heat --> Measure[Record Temperature at 1 mm Penetration]
    Measure --> VST[Vicat Softening Temperature]

Note: Strict adherence to Annex A is essential for accurate VST measurement.

Test Method for Resistance to External Blows at 0°C per IS 15328 Annex B

Overview (Clause 8.1)

• Objective: Assess resistance of thermoplastic pipes, including unplasticized PVC, to external impacts at 0°C.
• Applicable to isolated production batches.
• Manufacturer provides three pipe samples of various diameters/classes from routine production.

Sampling Plan (Table 15)

• Acceptance number indicates maximum allowable failures to pass.
• Rejection number indicates failure count to reject batch.
• Retesting performed if initial results are borderline.

Test Procedure

• Pipes conditioned at 0°C.
• External blows applied as specified.
• Batch passes if number of failures is less than or equal to acceptance number.

Additional Notes

• This serves as a type test (Clause 2.1.1.1).
• Samples must originate from normal production.
• Ensures impact durability in cold environments.

flowchart LR
    SelectLot --> SamplePipes[Select 3 Pipe Samples]
    SamplePipes --> Condition[Condition at 0°C]
    Condition --> ApplyImpacts[Apply External Blows]
    ApplyImpacts --> FailCheck{Failures ≤ Acceptance Number?}
    FailCheck -- Yes --> Pass[Batch Accepted]
    FailCheck -- No --> Fail[Batch Rejected]

Summary of Sampling Procedures per IS 15328

Essential Tables and Clauses

• Table 13 (Clause 1.4.1) details visual and dimensional sampling.

Random Sampling (Clause 1.4.2)

• Use random number tables (IS 4905) or systematic sampling by selecting every rth pipe, where [ r = \left\lfloor \frac{N}{n} \right\rfloor ]
• N is lot size, n is sample size.

Sampling Steps

1. Determine lot size (N).
2. Identify sample size (n) from Table 13.
3. Select samples randomly or systematically.
4. Apply acceptance/rejection criteria.

flowchart TD
    Start[Identify Lot Size (N)] --> SampleSize[Determine Sample Size (n)]
    SampleSize --> CalculateR[Compute r = floor(N/n)]
    CalculateR --> RandomCheck{Use Random Table?}
    RandomCheck -- Yes --> RandomSelect[Select Samples Randomly]
    RandomCheck -- No --> SystemSelect[Select Every rth Pipe]
    RandomSelect & SystemSelect --> InspectSamples[Perform Inspection]
    InspectSamples --> Decision{Accept or Reject}