high-density polyethene pipes for potable water supplies

IS 4984: Scope Key Points and Tables

Scope Overview

• Applies to High-Density Polyethylene (HDPE) pipes for water supply.
• Dimensional tolerances and ovality correspond to Grade N of ISO/DIS 11922-1.
• Sampling and acceptance criteria for visual and dimensional defects are specified.

Key Tables and Specifications

1. Sampling Plan for Visual and Dimensional Requirements (Table 7)

IS 4984: High Density Polyethylene Pipes for Water Supply - Key References

1. Material Grades & Strength (Table 1, Clause 1.60)

• Max water temperature recommended: +45°C
• Ambient temperature range: -40°C to +45°C
• Apply pressure coefficient (Fig. 1 in code) for temperature adjustments.

2. Pipe Dimensions & Tolerances (Table 2, Clause 6.1)

• Ovality per ISO/DIS 11922-1 Grade N.

3. Wall Thickness (Clause 6.2, Tables 3-5)

• Separate tables for PE 63, PE 80, PE 100.
• Thickness varies with Nominal Diameter (DN) and Pressure Rating (PN).
• Example for PE 100 at PN 16:

4. Test Conditions (Annex C-2.2)

Designation of Pipes (IS 4984)

• Format:
  Material Grade + Pressure Rating + Nominal Diameter
  Example: PE 63 PN 10 DN 200
  • PE 63 = Material Grade
  • PN 10 = Pressure Rating (1.0 MPa)
  • DN 200 = Nominal Diameter (200 mm outside diameter)

1. Material Grades & Strength (Clause 3.2.1, Table 1)

2. Pressure Rating (PN) (Clause 3.3)

• Pressure rating (PN) corresponds to the maximum working pressure in MPa at 20°C.
• Adjust pressure for temperature using pressure coefficient (refer Fig.1 in IS 4984).

3. Nominal Diameter (DN) (Clause 3.4)

• DN is the outside nominal diameter in mm.
• Pipes are classified by DN for standardization.

4. Reworked Material (Clause 5.4)

• Up to 10% of manufacturer's own rework material allowed.
• No other recycled material permitted.

Summary Formula for Pipe Designation:

Pipe Designation = PE [Material Grade] + PN [Pressure Rating in MPa] + DN [Nominal Diameter in mm]

If you want, I can provide the pressure coefficient chart or pipe dimension tables next!

IS 4984: Material Requirements for PE Pipes

1. Grade of Material (Clause 3.2 & Table 1, Clause 1.60)

• MRS = Minimum Required Strength (long-term strength for 50 years)
• Max water temperature recommended: +45°C
• Ambient temperature range: -40°C to +45°C
• Use temperature correction factor (pressure coefficient) from Fig. 1 for higher temperatures.

2. Melt Flow Rate (MFR) (Clause 5.2.2)

• MFR range: 0.41 to 1.10 g/10 min at 190°C, 5 kg load (IS 2530:1963 method).
• MFR must be within ±20% of manufacturer's declared value.

3. Reworked Material (Clause 5.4)

• Up to 10% of manufacturer's own rework material allowed.
• No other recycled/reworked materials permitted.

Summary Diagram: Material Grade vs. Stress Limits

graph LR
    PE63["PE 63\nMRS=6.3 MPa\nMax Stress: 5.0 MPa @20°C"]
    PE80["PE 80\nMRS=8.0 MPa\nMax Stress: 6.3 MPa @20°C"]
    PE100["PE 100\nMRS=10.0 MPa\nMax Stress: 8.0 MPa @20°C"]
    PE63 -->|Higher Temp ↓| PE80
    PE80 -->|Higher Temp ↓| PE100

Use these values for design pressure and material selection per IS 4984.

IS 4984: Physical & Chemical Properties Key Points

1. Material Classification & Strength (Clause 1.60, Table 3.3)

• Note: Max water temp = +45℃; ambient temp range: -40℃ to +45℃.
• Use pressure coefficient (Fig.1) to adjust max working pressure for temperature variations.

2. Test Conditions (Clause 2.2)

3. Anti-oxidant Content (Clause 5.3)

• Max 0.3% by mass of finished resin.
• Must be physiologically harmless as per IS 10141:1982.

4. Hydraulic & Physical Tests (Clause 9.2.4)

• Includes: Hydraulic characteristics, reversion, overall migration, density, melt flow rate (MFR), carbon black content/dispersion.

Pressure Adjustment Formula:

[ P_{adj} = P_{rated} \times C_T ]

Where:

• (P_{adj}) = Adjusted pressure at temperature T
• (P_{rated}) = Rated pressure at 20℃
• (C_T) = Pressure coefficient from Fig.1 (varies with temperature)

flowchart LR
    A[Material Grade] --> B{MRS at 20℃}
    B --> C[Hydrostatic Stress @ 20℃]
    B --> D[Hydrostatic Stress @ 

IS 4984: Dimensions and Tolerances for Thermoplastic Pipes

1. Outside Diameter Tolerances

• No negative tolerances allowed.
• Tolerances on outside diameter calculated as 0.009 × DN rounded to next 0.1 mm, minimum 0.3 mm (Clause A-2.1).

2. Ovality

• Ovality corresponds to Grade N of ISO/DIS 11922-1.
• Ovality values are as per Table 2 in IS 4984 (refer Clause 6.1 and A-2.2).

Summary Formula for Outside Diameter Tolerance:

[ \text{Tolerance} = \begin{cases} \max(0.008 \times DN + 1.0, 1.2) \text{ mm} & \text{if } DN \leq 75 \ 0.02 \times DN \text{ mm} & \text{if } 75 < DN \leq 250 \ 0.035 \times DN \text{ mm} & \text{if } DN > 250 \end{cases} ]

(All values rounded up to next 0.1 mm)

Visual Summary: Diameter Tolerance vs DN

graph LR
A[DN ≤ 75] -->|Tolerance = 0.008DN + 1.0 (min 1.2 mm)| B(Tolerance)
C[75 < DN ≤ 250] -->|Tolerance = 0.02DN| B
D[DN > 250] -->|Tolerance = 0.035DN| B

Note: Refer to IS

IS 4984: Marking Specifications for Pipes

Key Marking Requirements (Clause 10.1 & 10.2)

• Mark Location:

  • On each end of straight pipe lengths
  • On both ends of coils or hot embossed every 1 meter on white base throughout coil length

• Marking Details:

  • Manufacturer's name or trademark
  • Indelible ink/paint or hot embossing
  • Standard Mark (BIS Certification Mark) may also be applied as per Clause 10.2

BIS Certification Mark (Clause 10.2 & 10.2.1)

• Use of the Standard Mark is regulated under the Bureau of Indian Standards Act, 1986.
• Licensing conditions for use of the Standard Mark are provided by BIS.
• Pipes bearing this mark confirm compliance with IS 4984 quality standards.

Additional Notes

• Marking must be clear and legible for identification throughout handling and installation.
• For coils, marking every meter ensures traceability along the length.

Summary Table for Marking

flowchart LR
    A[Pipe Length] --> B[Mark Both Ends]
    C[Pipe Coil] --> D[Mark Both Ends + Every 1m]
    B & D --> E[Manufacturer Name/Trademark]
    E --> F[Optional BIS Standard Mark]

This ensures traceability, quality assurance, and compliance with IS 4984.

IS 4984: Performance Requirements for HDPE Pipes

Key Specifications & Formulas

1. Material Grades & Strength (Clause 1.60, Table 3.3)

• Note: Max water temperature recommended = +45°C; ambient temperature range = -40°C to +45°C.
• Adjust working pressure using pressure coefficient (temperature correction) from Fig. 1 (not shown here).

2. Wall Thickness Testing (Clause 2.2, Annex C-2.2)

• Applies for hydrostatic strength and reversion tests.

3. Performance Tests (Clause 9.2.4 & 9.2.4.1)

• Hydraulic characteristics
• Reversion (thermal stability)
• Overall migration (chemical stability)
• Density
• Melt Flow Rate (MFR)
• Carbon black content and dispersion

Practical Formula for Design Pressure (P):

[ P = \frac{2 \times S \times \sigma}{D} ]

Where:

• (P) = Design pressure
• (S) = Wall thickness (mm)
• (\sigma) = Allowable stress (MPa) from MRS and temperature correction
• (D) = Outside diameter (mm)

flowchart LR
    A[Material Grade] --> B[MRS & Design Stress]
    B --> C[Temperature Correction]
    C --> D[Calculate Max Working Pressure]
    D --> E

IS 4984: Sampling and Testing Key Points

1. Sampling for Dimensional & Visual Requirements (Clause 9.2.3.1)

Use Table 7 for sample size and acceptance criteria based on lot size:

• Acceptance Criteria: Lot passes if defectives ≤ Acceptance No. in cumulative sample.

2. Sampling for Hydraulic & Other Tests (Clause 9.2.4.2)

Use Table 8 for sample size based on lot size:

IS 4984: Certification and Marking Key Points

1. BIS Certification Mark (Clause 10.2 & 10.2.1)

• Pipes may be marked with the BIS Standard Mark.
• Use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986.
• Licence conditions for use of the Standard Mark are obtained from BIS.

2. Sampling for Tests (Clause 9.2.4.2 - Table 8)

• Tests include: Hydraulic characteristics, Reversion, Overall migration, Density, MFR, Carbon black content, Dispersion.

3. Test Procedure (Clause 2.3)

• After oven testing, cool samples in air without movement at ambient temperature.
• Measure the minimum distance between two marks for reversion.

This ensures quality control and traceability of pipes under IS 4984.

IS 4984 - Explanatory Notes on Material & Dimensions: Key Points

1. Outside Diameter, Tolerance & Ovality (Table 2, Clause 6.1)

• Ovality corresponds to Grade N of ISO/DIS 11922-1.
• Tolerances increase with diameter.

2. Wall Thickness for Material Grades (Clause 6.2)

• Grades: PE 63, PE 80, PE 100.
• Thickness varies with Nominal Diameter (DN) and Pressure Rating (PN).
• Tables 3, 4, 5 provide min/max thickness (mm) for each grade and PN.

3. Sample Wall Thickness Range for PE 63 (Table 3)

4. Wall Thickness Test Conditions (Clause 2.2, Annex C)

Summary Formula for Pipe Thickness (approximate for design):

[ S = \frac{P \times D}{2 \times (\sigma - P \times Y)} ]

Where:

• (S) = wall thickness
• (P) = design pressure
• (D\

IS 4984: Hydraulic Characteristics Test Procedure

Key Points from Clause 8.1 & 9.2.4:

• Test: Internal pressure creep rupture test (Annex B)
• Acceptance Criteria: No localized swelling, leakage, weeping, or bursting during test.
• Test Conditions: Temperature, duration, and induced stress per Table 6 (not provided here, refer IS 4984 Table 6).
• Sample Size (Clause 9.2.4.2):

• Lot Testing: Per Clause 9.2.4.1, after dimensional & visual checks, test for hydraulic characteristics and related parameters.

Typical Test Parameters (from IS 4984 and general practice):

Summary:

• Perform internal pressure creep rupture test per Annex B.
• Use sample size based on lot size (see table).
• Pipes must not fail (no leakage, swelling, or burst).
• Follow temperature, duration, stress from Table 6.

flowchart TD
    A[Start: Lot Received] --> B{Dimensional & Visual Check}
    B -- Pass --> C[Select Sample Size]
    C --> D[Conduct Hydraulic Characteristics Test]
    D --> E{No Leakage/Swelling/Burst?}
    E -- Yes --> F[Lot Accepted]
    E -- No --> G[Lot Rejected]

For detailed test setup, refer to Annex B of IS 4984 and Table 6 for exact temperature & stress values.

IS 4984: Longitudinal Reversion Test - Key Points

1. Test Objective:

• Measure the longitudinal reversion (recovery of length after deformation) of pipes.
• Acceptable limit: Longitudinal reversion ≤ 3% (Clause 8.2).

2. Calculation of Longitudinal Reversion (T):

From Annex C, Clause 3.1:

[ T = \frac{L_0 - L_1}{L_0} \times 100 ]

• (L_0) = Original length of test piece (mm)
• (L_1) = Length after test (mm)
• (T) = Longitudinal reversion in %

3. Test Pressure Calculation (Clause 4.3):

[ p = \frac{2 \times s \times d_i}{d} ]

• (p) = Test pressure (MPa)
• (s) = Minimum wall thickness (mm)
• (d_i) = Induced stress from Table 6 (MPa)
• (d) = Outside diameter of pipe (mm)

4. Test Procedure Highlights (Annex C & Clause 4.3):

• Gradually increase pressure to (p) within 10–30 seconds in a temperature-controlled bath.
• Maintain pressure ±2.5% for duration from Table 6.
• No leakage, swelling, or bursting allowed.
• Failures near end caps are disregarded; test must be repeated.

5. Table 6 (Typical Induced Stress Values & Test Duration):

(Refer IS 4984 Table 6 for exact values)

flowchart LR
    A[Prepare Test Piece] --> B[Measure Initial Length \(L_0\)]
    B --> C[Immerse in Temperature Bath]
    C --> D[Increase Pressure Gradually to \(p\)]