UPVC pipe fittings to be used with the UPVC pipes in the suction and delivery lines of agricultural pumps

IS 13593 - Scope & Sampling Specifications

Scope Summary:

• Applies to fittings conforming to requirements in clauses 6.1.2 (snow white color), 7.x, 8, 9.2.
• Sampling and acceptance criteria ensure lot conformity per Clause 10.2 and 10.3.1.

Key Table: Sampling & Acceptance (Table 3)

• Acceptance Number (A): Maximum defective fittings allowed for lot acceptance.
• Sampling ensures quality control under BIS supervision.

Additional Notes:

• Each sampled fitting is examined; if defects ≤ acceptance number, lot is accepted.
• Standard Mark usage governed by BIS Act, ensuring compliance and continuous monitoring.
• Fittings must be snow white (Clause 6.1.2).

flowchart TD
    A[Lot of Fittings] --> B[Select Sample Size (Table 3)]
    B --> C[Inspect Sample for Defects]
    C --> D{Defects ≤ Acceptance Number?}
    D -- Yes --> E[Lot Accepted]
    D -- No --> F[Lot Rejected]

This ensures quality assurance per IS 13593.

IS 13593 Key References: Sampling, Dimensions & Acceptance Criteria

1. Sampling and Acceptance (Clause 10.3.1, Table 3)

• Acceptance Number (A): Max defective fittings allowed for acceptance.
• Fittings are accepted if defectives ≤ Acceptance Number (A).

2. Dimensions of Threaded Pieces (Clause 7.4.2, Table 2)

3. Depth of Socket (Clause 7.3, Table 1)

| Type of Fitting | Nominal Size (mm) | Min Overall Length (mm) | Min Depth of Socket (mm) | Length of Flanged Portion (mm) | |-----------------|-------------------|-------------------------|

IS 13593 - Key Definitions & Specifications Summary

Sampling & Acceptance Criteria (Clause 10.3.1 & Table 3)

• Sampling size and permissible defectives depend on lot size.
• Acceptance number A allows some defectives; B is stricter (usually zero).

• A fitting lot passes if defective fittings ≤ acceptance number A.

Physical Specifications (Table 2 - Clause 7.4.2)

Additional Notes:

• Fittings must be snow white in color (Clause 6.1.2).
• Standard Mark usage is governed by BIS rules ensuring quality control.
• Sampling and acceptance are critical for quality assurance.

flowchart TD
    A[Lot of F

IS 13593: Material Requirements - Key Points

Sampling & Acceptance (Clause 10.2, 10.3.1)

• Sampling size depends on lot size (see Table 3, cols 1 & 2).
• Acceptance number (A) in Table 3 col 3 defines max allowable defective fittings.
• Lot is accepted if defective fittings ≤ A.

Dimensions (Clause 7.4.2)

• Minimum overall length, wall thickness, and thread length for threaded pieces are specified in Table 2.

Flanges (Clause 7.5)

• Metallic flanges must comply with IS 1536:1989 for material, dimensions, and drilling.
• Surfaces must be smooth, clean, and free from defects (cracks, pinholes, inclusions).

Typical Table 2 (Example for Threaded Pieces)

Table 3 (Sampling & Acceptance Example)

flowchart TD
    A[Lot Received] --> B{Sample Size from Table 3}
    B --> C[Inspect Samples]
    C --> D{Defective ≤ Acceptance Number?}
    D -->|Yes| E[Lot Accepted]
    D -->|No| F[Lot Rejected]

Summary:
Use Tables 2 & 3 for dimensions and sampling. Check flanges per IS 1536. Accept lot if defects ≤ acceptance number.

IS 13593: Nominal Sizes of Fittings - Key Specifications & Tables

1. Nominal Sizes

• Designated by nominal outside diameter of pipes as per IS 12231:1987.
• Sizes covered: 63, 75, 90, 110, 140 mm.

2. Table 1: Overall Length, Depth of Socket & Flanged Portion

*Lengths for bends are along outer curve.

3. Table 2: Threaded Pieces (Male/Female/Reducers)

IS 13593 - Classification of Fittings: Key Points

1. Classification by Lot (Clause 10.1)

• A lot consists of fittings of the same size, class, and fabrication conditions.
• Sampling and testing are done per lot for quality control.

2. Number of Tests and Acceptance Criteria (Clause 10.3 & 10.3.1)

• Each fitting selected from a lot is tested for specified requirements.
• A fitting failing one or more tests is acceptable only if the number of defective fittings ≤ acceptance number A (from Table 3).

3. Pressure Ratings (Clause 6.1.1)

• Fittings are classified by Class, each with a defined working pressure.
• Example:

(Refer to IS 13593 Table 1 for detailed classes and pressures.)

Summary Diagram:

flowchart TD
    A[Lot: Same size, class, fabrication] --> B[Sampling]
    B --> C{Test each fitting}
    C -->|Pass| D[Conforms]
    C -->|Fail| E{Defective fittings ≤ A?}
    E -->|Yes| D
    E -->|No| F[Lot Rejected]

This ensures systematic classification and quality control per IS 13593.

IS 13593: Dimensions for Threaded Fittings (Clause 7.4)

Key Specifications from Tables 1 & 2

Table 1 (Summary)

• Minimum overall length, socket depth, and flanged portion length for couplers, end pieces, bends, and reducer couplers.

Table 2: Minimum Dimensions for Threaded Pieces

Notes:

• Wall thickness and threaded length increase with nominal size.
• Sockets for reducers are

IS 13593 — Workmanship: Key Specifications & Sampling

1. Sampling & Acceptance Criteria (Clause 10.3.1 & Table 3)

• Acceptance Number (A): Max permissible defective fittings in sample for conformance.
• If defective fittings ≤ Acceptance Number (A), lot is accepted.

2. Dimensional Specifications (Clause 7.4.2 & Table 2)

• Minimum overall length, wall thickness, and threaded portion length must comply with Table 2 (not provided here).
• Ensure fittings meet these minimum dimensions for quality.

3. Workmanship Requirements

• Each fitting is examined for conformance.
• Defective fittings beyond acceptance number lead to rejection.
• Standard Mark usage governed by BIS ensures production under strict quality control.

Summary Diagram: Sampling & Acceptance Process

flowchart TD
    A[Start: Lot of Fittings] --> B[Determine Lot Size]
    B --> C[Select Sample Size from Table 3]
    C --> D[Inspect Sample Fittings]
    D --> E{Number of Defectives ≤ Acceptance Number?}
    E -- Yes --> F[Accept Lot]
    E -- No --> G[Reject Lot]

Note: Refer to IS 13593 Table 2 for exact dimensional values and ensure all fittings comply with workmanship and dimensional requirements before marking and dispatch.

IS 13593: Performance Requirements Summary

1. Number of Tests and Acceptance Criteria (Clause 10.3 & 10.3.1)

• Fittings are sampled and tested.
• A fitting failing one or more tests is still acceptable if defective fittings ≤ acceptance number A (from Table 3, col 3).
• Table 3 (Acceptance Number A) defines permissible defective fittings per sample size.

2. Dimensions of Flanges (Clause 7.5)

• Metallic flange dimensions and drilling per IS 1536:1989.
• Surfaces must be smooth, clean, and defect-free (no cracks, pinholes, inclusions).

3. Performance Requirements (Clause 9)

• Fittings must meet specified mechanical and visual criteria.
• Color: fittings shall be snow white (Clause 6.1.2).

4. Pressure-Temperature Relation

• Maximum continuous working pressure depends on temperature.
• Refer to Fig. 1 graph for coefficient to calculate pressure at temperatures up to 45°C.

Example: Acceptance Criteria Table (Excerpt from Table 3)

Formula for Maximum Working Pressure (P):

[ P = P_0 \times C_t ]

• P0 = Rated pressure at reference temperature.
• Ct = Temperature coefficient from Fig.1 (graph).

flowchart LR
    A[Select Sample of Fittings]
    B[Test Each Fitting]
    C{Number of Defective ≤ A?}
    D[Accept Batch]
    E[Reject Batch]

    A --> B --> C
    C -->|Yes| D
    C -->|No| E

Summary: Use Table 3 for acceptance numbers, IS 1536 for flange dimensions, and Fig.1 for pressure-temperature coefficients.

IS 13593: Sampling and Criteria for Conformity (Clause 10)

Sampling (Clause 10.2)

• Number of fittings to sample depends on lot size.
• Sampling follows Table 3:

  Lot Size (N)	Sample Size (n)	Acceptance Number (A)
  2 - 8	2	0
  9 - 15	3	0
  16 - 25	5	0
  26 - 50	8	1
  51 - 90	13	1
  91 - 150	20	2
  151 - 280	32	3
  281 - 500	50	5

Criteria for Conformity (Clause 10.3 & 10.3.1)

• Each sampled fitting is tested for all specified requirements.
• A lot is accepted if the number of defective fittings ≤ acceptance number (A) from Table 3.
• If defects exceed A, the lot is rejected.

Hydrostatic Test (Clause 9.2)

• Fittings must withstand internal hydrostatic pressure per IS 12235 (Part 8):1986.
• Test parameters (temperature, duration, stress) per Table 2 of IS 12231:1987.
• No bursting allowed during the test.

flowchart TD
    A[Lot of Fittings] --> B[Sample fittings as per Table 3]
    B --> C[Test each fitting for requirements]
    C --> D{Number of defects ≤ A?}
    D -- Yes --> E[Accept Lot]
    D -- No --> F[Reject Lot]

Summary: Sample size and acceptance criteria depend on lot size (Table 3). Hydrostatic tests ensure pressure resistance. Acceptance is based on defect count relative to acceptance number.

IS 13593: Marking of Fittings — Key Specifications & Sampling

Clause 11.1 - Marking Requirements:

• All fittings must be clearly and indelibly marked or embossed at a prominent place with:
  • Manufacturer's name or identification mark
  • Size and class of fitting
• Clause 11.1.1: Each fitting may also carry the BIS Standard Mark.

Clause 6.1.2:

• Fittings shall be snow white in colour.

Sampling & Acceptance Criteria (Clause 10.3.1, Table 3)

• Acceptance Number (A) and (B) define permissible defectives for lot acceptance.
• Sampling ensures quality control under BIS supervision.

Notes on BIS Standard Mark:

• Indicates compliance with IS standards.
• Issued under BIS Act, 1986.
• License for use granted under strict inspection and testing.

flowchart LR
    A[Fittings Lot] --> B[Sampling per Table 3]
    B --> C{Defectives ≤ Acceptance Number?}
    C -->|Yes| D[Lot Accepted]
    C -->|No| E[Lot Rejected]
    D --> F[Mark fittings with Manufacturer's ID, Size, Class]
    F --> G[Optional BIS Standard Mark]

Summary:
Mark fittings with manufacturer ID, size, class, and optionally BIS mark. Use Table 3 for sampling and acceptance criteria to ensure quality compliance. Fittings must be snow white.