unplasticized polyvinyl chloride (PVC-U)screen and casing pipes for bore/tubewell

IS 12818: Scope - Key Specifications and Tables

This standard covers Metric Trapezoidal Threads and Sealing Elements for pipes DN 100 to 400.

1. Thread Profiles & Dimensions

• DN 100 to 200 (Table 11):

• DN 250 to 400 (Table 12):

2. Sealing Element Dimensions (Table 13)

IS 12818 Key References, Tables & Specifications Summary

1. References (Table 2)

• IS 554: Pipe threads for pressure-tight joints (dimensions & tolerances)
• IS 4669: Test methods for PVC resins
• IS 4985: UPVC pipes for potable water (specification)
• IS 10148 & 10151: Constituents & specs for PVC safe in contact with food/drinking water
• IS 12235: Thermoplastics pipes & fittings test methods

2. Trapezoidal Thread Dimensions

(Refer Tables 11 & 12 for DN 100–400)

3. Sealing Element Dimensions (Table 13)

IS 12818: Terminology and Definitions - Key Specifications & Tables

1. Terminology

• Defines terms related to pipe threads, sealing elements, screen pipes, and acceptance tests for conformity.
• Important for understanding dimensions, test procedures, and acceptance criteria.

2. Key Tables

Table 11 & 12: Trapezoidal Threads Dimensions

All dimensions in mm; refer to IS 12818 for exact values.

Table 13: Sealing Element Dimensions (DN 100 to 400)

Table 10: Slot Dimensions on Screen Pipes

• Defines number of slots (N min), slot width (w), and free passage area (%) for various DN sizes.
• Example: DN 100, RDS pipe, 5 slots minimum, slot width 0.3 mm → free passage area ~5.2%.

3. Acceptance Tests (Clause 10.1.5)

• Lot acceptance based on defectives in sample size per **Table

IS 12818: Material Requirements - Key Formulas, Tables & Specs

1. Trapezoidal Threads Dimensions

(Refer Table 11 & 12 for full range DN 100 to 400)

2. Sealing Element Dimensions (DN 100 to 400)

(See Table 13)

3. Screen Pipe Slots & Passage Area

• Minimum slots on circumference (N) depend on DN.
• Approximate free passage area (%) varies with slot width (w).
• Width between slots (b) tolerance: ±0.5 mm.
• Example

IS 12818: Classification and Designation - Key Specifications

1. Classification (Clause 11.1 - Marking)

• Pipes are marked by color:
  • Red: RMS, PMS, CS pipes
  • Yellow: CM pipe
  • Green: CD and RDS pipes
• Marking includes:
  • Manufacturer source
  • Pipe type code (RMS, RDS, PMS, PDS, CS, CM, CD)
  • Nominal diameter (DN) in mm
  • Slot size in mm
  • Effective pipe length in mm

2. Designation (Tables for Threads & Sealing Elements)

• Metric Trapezoidal Threads (DN 100 to 400):

• Sealing Element Dimensions (DN 100 to 400):

3. Acceptance Testing (Sampling - Table 15)

IS 12818: Dimensions and Tolerances Summary

1. Trapezoidal Thread Dimensions

• DN 100 to 200 (Table 11)

• DN 250 to 400 (Table 12)

2. Sealing Element Dimensions (DN 100 to 400) - Table 13

IS 12818: Screen Pipes — Key Specifications & Tables

1. Slot Dimensions & Free Passage Area (Table 10)

• N = Minimum number of slots on pipe circumference.
• Σα +5% = Total slot length with 5% tolerance.
• Width of slot (w) varies: 0.2 mm to 3.0 mm.
• Approximate free passage area (%) depends on slot width and pipe size (DN).
• Width of material between slots (b) ± 0.5 mm (can be up to +2 mm for max 10 slots/meter).

2. Slot Width Tolerances (Clause 7.5.2)

3. Pipe Dimensions (Examples)

• Ribbed Deep Well Screen (RDS) Pipes (Table 2):
  • DN 100: Mean OD 117 mm, Wall thickness 7.0–7.9 mm
  • DN 400: Mean OD 454 mm, Wall thickness 23.5–26.1 mm
• Plain Medium Well Screen (PMS) Pipes (Table 3):
  • DN 200: OD ~

Threading of Screen and Casing Pipes (IS 12818: Clause 8.3)

• Applicable Sizes: Nominal diameter 100 mm to 400 mm.
• Thread Type: Metric trapezoidal threads as per Clause 8.3.1 and 8.3.2.
• Reference Table: Table 11 (Clause 8.3.1) provides detailed thread dimensions for sizes 100 to 200 mm (not fully provided here).
• Thread Protection: Undercut for sealing ring and thread protection as shown in Fig. 1C to avoid damage during assembly.
• Dimensional Control: Threads are designed considering mean outer diameter over connection (d_c), ensuring proper fit and sealing.

Key Dimensions for Pipes (Selected from Tables 2, 5, 7):

Threading Notes:

• Threads conform to metric trapezoidal profile ensuring strength and sealing.
• Undercuts protect threads and provide space for sealing rings.
• Thread dimensions depend on pipe size and wall thickness; exact pitch and depth are in Table 11 (IS 12818).

flowchart LR
  A[Pipe Body] --> B[Threaded End]
  B --> C[Undercut for Seal Ring]
  B --> D[Thread Profile: Metric Trapezoidal

IS 12818: Physical and Mechanical Properties - Key Formulas and Tables

1. Resistance to External Blows (Clause 9.4)

• Test per IS 12235 (Part 9) at 0°C.
• True Impact Rate ≤ 10%.
• Test on pipe plain/ribbed portion, min 100 mm from socket root.
• Parameters from Table 14: Mass of Striker & Height of Free Fall

Tolerances: ±0.5% mass, ±10 mm height.

2. Trapezoidal Thread Dimensions (Clause 8.3)

• For DN 100 to 200 (Table 11):

• For DN 250 to 400 (Table 12):

| DN | Outside Dia. d (mm) | d2 (mm) | d1 (mm) | D

IS 12818: Sampling and Criteria for Conformity (Clause 10.1 & Table 15)

Key Points:

• Sampling is done in two stages for acceptance tests (Clauses 7, 8, 9.1, 9.2, 9.3, 9.4).
• Acceptance or rejection depends on the number of defectives found in the sample.
• If defectives in the first sample are between acceptance and rejection limits, a second sample is taken.
• The cumulative defectives from both samples determine lot acceptance.

Table 15 Summary (Scale of Sampling & Criteria)

Acceptance Criteria:

• If defectives ≤ Acceptance No. → Lot accepted.
• If defectives ≥ Rejection No. → Lot rejected.
• If defectives lie

IS 12818: Marking and Packaging Key Points

Marking (Clause 11.1)

• Colour Coding:
  • Red: RMS, PMS, CS pipes
  • Yellow: CM pipe
  • Green: CD and RDS pipes
• Marking Details:
  • Manufacturer's source
  • Pipe type (RMS, RDS, PMS, PDS, CS, CM, CD)
  • Nominal diameter (mm)
  • Slot size (mm)
  • Effective pipe length (mm)
• Optional: BIS Standard Mark (Clause 11.2)

Packaging & Testing (Clause 9.4, 10.1.4, 10.1.5)

• Tolerances: ±0.5% mass, ±10 mm height
• Used for impact resistance testing of pipes.

Thread & Sealing Dimensions (Clause 8.3, 8.4)

• Trapezoidal Thread Dimensions for DN 100-400 (select examples):

IS 12818: Testing Methods Key Points

1. Acceptance Tests (Clause 10.1.5 & Table 15)

• Lot testing involves sub-samples from initial tests (Clause 10.1.4).
• Number of defectives in the first sample compared with:
  • Acceptance Number (Ac): max allowed defectives to accept lot.
  • Rejection Number (Re): min defectives to reject lot.
• Sampling sizes and acceptance/rejection numbers are detailed in Table 15 (not fully provided here).

2. Tests under Clause 9.4 (Table 15 reference)

• Number of test repetitions (cols 10-13) indicate times tests are performed, not number of samples or failures.
• Tests include physical and dimensional checks per specifications.

3. Type Tests (Clause 10.2)

• Performed to validate design and manufacturing process.
• Includes mechanical, dimensional, and sealing tests.

Summary Table: Acceptance Criteria (Example format from Table 15)

Additional Notes:

• Refer to Tables 11-13 for thread and sealing element dimensions critical for testing.
• Testing ensures compliance with dimensional tolerances and sealing integrity.

flowchart TD
    A[Start: Lot Sample] --> B{Test 9.3 & 9.4}
    B -->|Defectives ≤ Ac| C[Accept Lot]
    B -->|Defectives ≥ Re| D[Reject Lot]
    B -->|Ac < Defectives < Re| E[Further Testing]
    E --> B

For detailed sampling and acceptance numbers, consult Table 15 in IS 12818.

IS 12818 (Part 4) - Effect on Water Quality: Key Points

• Clause 9.7: Pipes must not adversely affect the water composition flowing through them.
• Testing Standard: Pipes should comply with IS 4985 (Clause 10.3) for water composition effects.
• Test Method: Use IS 12235 (Part 4) for testing pipe material effects on water quality.
• Table 15 (Clause 9.4): Specifies limits for various water quality parameters after exposure to pipe material.
• Sampling & Conformity: Clause 10 outlines sampling methods and acceptance criteria for pipe batches.

Typical Parameters Checked (from IS 4985 & IS 12818 context):

Summary:

• Pipes must pass water quality tests per IS 4985: no harmful leaching or alteration.
• Testing per IS 12235 ensures pipes do not deteriorate water quality.
• Table 15 provides specific parameter limits (refer IS 12818 for exact values).

flowchart LR
    A[Pipe Material] --> B[Test per IS 12235]
    B --> C{Meets IS 4985 Water Quality Criteria?}
    C -->|Yes| D[Pipe Approved]
    C -->|No| E[Reject Pipe Batch]

In brief: Ensure pipes meet IS 4985 water quality criteria through IS 12235 testing, with parameters per Table 15 of IS 12818.

IS 12818 - Certification and BIS Marking Key Points

BIS Certification Marking (Clause 11.2.1)

• Use of the Standard Mark is regulated by the Bureau of Indian Standards Act, 1986.
• Licence for use of the Standard Mark is granted under BIS rules.
• Pipes may be marked with the Standard Mark as a quality assurance symbol.
• BIS holds copyright of all publications; reproduction requires permission except for necessary details in implementation.

BIS Contact & Offices

• Headquarters: Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi 110002
• Regional Offices: Central (Delhi), Eastern (Kolkata), Northern (Chandigarh), Southern (Chennai), Western (Mumbai)
• Multiple branch offices across India.

Important Tables for Pipe Threads & Sealing Elements (for reference)

Summary

• Certification Mark ensures compliance with BIS standards.
• Marking on pipes indicates conformity.
• Contact BIS for licensing.
• Use the provided tables for correct thread and sealing element dimensions.

For detailed licensing conditions, contact BIS directly.

flowchart LR
    A[Manufacturer] --> B{Apply for BIS License}
    B -->|Approved| C[Use Standard Mark on Product

IS 12818 Key Annexes, Tables & Figures Summary

1. Acceptance Tests (Clause 10.1.5)

• Lot testing per Table 15 (sample sizes, acceptance/rejection numbers).
• Defectives ≤ acceptance number → lot accepted.
• Defectives ≥ rejection number → lot rejected.

2. Thread Profiles & Dimensions

3. Sealing Element Dimensions (Table 13, Clause 8.4.1)

• Ring seal diameter, height (Hp), and width (b) specified per DN.
• Example: DN 100 → Diameter = 107.4 ±0.5 mm, Height = 4.2 ±0.15 mm.

4. Figures

• Fig. 3 & 4: Show metric trapezoidal thread profiles for DN 100–200 and DN 250–400 respectively.
• Fig. 2A & 2B: Layout and dimensions of screens (Clause 7.5.1).

Typical Thread Dimension Parameters (for DN 100 to 200)

Acceptance Sampling Concept (Clause 10.1.5)

flowchart TD