self-closing taps for water supply purposes

IS 1711 Scope & Key Specifications Summary

• Scope: Covers materials, design, and testing of self-closing taps with emphasis on material standards and rounding off test results per IS 2-1960.

• Rounding Off (Clause 0.5):
  Final test values must be rounded to the same significant figures as specified, following IS 2-1960.

• Materials for Components (Clause 4.1, Table 1):

Important Notes:

• Material grades ensure durability and corrosion resistance.
• The standard revision includes updates on materials and finishes.
• Testing results must be consistent with IS 2-1960 rounding rules.

flowchart TD
    A[Self-Closing Tap Components]
    A --> B[Body, Cover, Lever]
    A --> C[Spindle]
    A --> D[Spindle Spring]
    A --> E[Cage & Valve]
    A --> F[Washers]
    A --> G[Gasket]

    B -->|Material| H[Grey Cast Iron, Malleable Iron, Brass, Leaded

IS 1711 - Definitions & Materials for Self-Closing Taps

Key Definitions (Clause 2.0)

• Defines terms used in the standard for clarity and uniformity.
• Final test values rounded per IS 2-1960 rules (Clause 0.5).

Materials for Components (Clause 4.1, Table 1)

*Note: Mild steel spindles only for cast iron/malleable iron push-button taps.

Rounding Off Values (Clause 0.5)

• Round test/calculated results to the same decimal places as specified values per IS 2-1960.

Summary Diagram

graph TD
A[Self-Closing Tap Components] --> B[Body, Cover, Lever/Button]
A --> C[Spindle]
A --> D[Spindle Spring]
A --> E[Cage and Valve]
A --> F[Brass Washer]
A --> G[Seat Washer & Others]
A --> H[Gasket]

B --> I[Grey Cast Iron, Malleable Iron, Cast Brass, Leaded Tin Bronze]

IS 1711 - Nominal Size for Self-Closing Taps

• Definition (Clause 3.1.1):
  Nominal size refers to the nominal bore diameter of the inlet connection of the tap.

• Nominal Sizes Covered (Clause 3.1):
  Self-closing taps are specified by their nominal sizes, typically matching standard pipe diameters such as:

  • 15 mm (1/2 inch)
  • 20 mm (3/4 inch)
  • 25 mm (1 inch)

• Lot Grouping (Clause 9.1):
  All taps of the same nominal size manufactured under similar conditions form a lot for quality control.

Summary Table of Nominal Sizes (Typical)

Key Notes:

• Nominal size is directly linked to the inlet bore diameter, affecting flow capacity.
• Ensure compatibility of tap nominal size with pipework for proper fitting and performance.

flowchart LR
    A[Pipe Nominal Bore] --> B[Tap Nominal Size]
    B --> C[Flow Capacity]
    B --> D[Lot Grouping for QC]

This ensures standardized sizing and quality in self-closing taps per IS 1711.

IS 1711 - Materials for Self-Closing Taps (Clause 4.1)

Notes:

• Mild steel spindles are suitable only for cast iron and malleable iron push-button taps.
• If the body is leaded tin bronze, the outside surface shall be polished bright (Clause 7.2).

This table summarizes key materials and their IS standards for various tap components ensuring durability and compliance.

flowchart TD
    A[Self-Closing Tap] --> B[Body, Cover, Lever]
    A --> C[Spindle]
    A --> D[Spindle Spring]
    A --> E[Cage and Valve]
    A --> F[Brass Washer]
    A --> G[Seat Washer & Others]
    A --> H[Gasket]

    B -->|Materials| I[Grey Cast Iron, Malleable Iron, Cast Brass, Leaded Tin Bronze]
    C -->|Materials|

IS 1711: Manufacture and Workmanship - Key Specifications

Materials for Components (Clause 4.1, Table 1)

Workmanship (Clause 7.2)

• If the body is leaded tin bronze, the outside surface shall be polished bright.

Summary:

• Use specified IS grade materials for each component to ensure durability and compatibility.
• Maintain surface finish quality especially for leaded tin bronze parts.
• Springs must have minimum tensile strength as per phosphor bronze wire standards.

graph TD
A[Self-Closing Tap Components] --> B[Body, Cover, Lever]
A --> C[Spindle]
A --> D[Spindle Spring]
A --> E[Cage & Valve]
A --> F[Washers & Gaskets]

B --> B1[Grey Cast Iron (IS 210)]
B --> B2[Malleable Iron (IS 2108)]
B --> B3[Cast Brass (IS 

IS 1711: Constructional Requirements for Self-Closing Taps (Clause 4.1)

Key Material Specifications (Table 1)

*Note: Mild steel spindles are suitable only for cast iron and malleable iron push-button taps.

Additional Specifications

• Rounding off test results: Follow IS 2-1960 for rounding values to maintain significant digits.
• Material grades ensure durability and corrosion resistance critical for tap components.

Summary Diagram: Material-Component Relationship

graph TD
  A[Self-Closing Tap] --> B[Body, Cover, Lever/Button]
  A --> C[Spindle]
  A --> D[Spindle Spring]
  A --> E[Cage and Valve]
  A --> F[Brass Washer]
  A --> G[Seat Washer & Other Washers]
  A --> H[Gasket]

  B -->|Grey Cast Iron, Malleable Iron, Cast Brass, Leaded Tin Bronze| M1
  C -->|Mild

IS 1711: Machining and Finishing - Key Points & Specifications

Clause 7.1: Machining Requirements

• Machining must ensure parts are true to shape and correctly adjusted when assembled.
• All machined surfaces should have a smooth finish to ensure proper functioning.

Clause 7.2: Surface Finishing

• For bodies made of leaded tin bronze, the outside surface shall be polished bright.

Materials & Specifications for Components (Clause 4.1, Table 1)

Additional Notes:

• Mild steel spindles are suitable only with cast iron and malleable iron pushbutton self-closing taps.
• Machining tolerances and surface finish quality should comply with general engineering good practice ensuring fit and function.
• Refer to IS 4346-1982 for detailed specifications on washers and gaskets.

Summary Diagram: Machining & Finishing Flow

flowchart TD
    A[Raw Casting] --> B[Machining]
    B --> C[Check Shape & Adjustment]
    C --> D{Material Type}
    D -->|Leaded Tin Bronze| E[Polish Outside Surface Bright]
    D -->|Others| F[Smooth

IS 1711: Performance Requirements Summary

Key Specifications & Tests

• Endurance Test (Clause 8.3):

  • Tap must withstand 50,000 operations (open-close cycles) without leakage or spring failure.

• Sampling for Conformity (Clause 9.3):
  Number of taps to be selected from a lot for testing:

• Material Specifications (Clause 4.1):
  Components must conform to IS standards; e.g.,
  • Body, cover, lever: Grey cast iron (IS 210-1978), Malleable iron (IS 2108-1977), Cast brass (IS 292-1983), Leaded tin bronze (IS 318-1981)
  • Spindle: Mild steel (IS 280-1978), Leaded tin bronze (IS 318-1981)
  • Springs: Phosphor bronze or spring steel wire (IS 7608-1975)
  • Washers and gaskets: As per IS 410-1977, IS 4346-1982

Rounding Off (Clause 0.5)

• Final test values must be rounded according to IS 2-1960, maintaining the same significant digits as the specified values.

Quick Reference: Endurance Test Criterion

Number of Operations (N) = 50,000  
No leakage or failure allowed.

Mermaid Diagram: Sampling Process

flowchart TD
    A[Lot of Taps] --> B{Lot Size?}
    B -->|≤200| C[Select 2 taps]
    B -->|201-300| D[Select 3 taps]
    B -->|301-500| E[Select 4 taps]
    B -->|501-800| F[Select 5 taps]
    B -->|>800| G[Select 7 taps]
    C --> H[Test for conformity]
    D --> H
    E --> H

IS 1711: Sampling and Criteria for Conformity (Clauses 9.3 & 9.4)

Sampling Plan (Clause 9.3)

Endurance Test (Clause 8.3)

• Each selected tap must withstand 50,000 operations (handle/pushbutton actuations).
• No leakage or failure of springs/working parts allowed.

Criteria for Conformity (Clause 9.4)

• If all sampled taps pass, the lot is accepted.
• If 1 or 2 taps fail, double the sample size and retest:
  • If all retested taps pass, accept the lot.
  • If more than 2 fail initially or any fail in retest, reject the lot unless every tap is individually tested.

Additional Notes

• Results must be rounded per IS 2-1960.
• Sampling should be random to ensure representativeness.

flowchart TD
    A[Select Sample as per Lot Size] --> B[Conduct Endurance Test (50,000 cycles)]
    B --> C{All taps pass?}
    C -- Yes --> D[Accept Lot]
    C -- No --> E{Failures ≤ 2?}
    E -- No --> F[Reject Lot or Test All Taps]
    E -- Yes --> G[Double Sample Size & Retest]
    G --> H{All retest taps pass?}
    H -- Yes --> D
    H -- No --> F

This ensures quality control by statistically verifying durability and functionality of taps.

IS 1711: Marking of Taps (Clause 10.1)

Key Specifications for Marking:

• Each tap shall be clearly and permanently marked with:

  • Manufacturer's name or trade-mark
  • Nominal size of the tap

• Taps may also carry the ISI Certification Mark, indicating compliance with IS standards and quality control.

Notes on ISI Certification Mark:

• Governed by the Indian Standards Institution (Certification Marks) Act.
• Ensures products meet defined inspection, testing, and quality control.
• Continuous conformity checks by ISI.

Summary Table for Marking Requirements

Additional Reference:

• For rounding off test values, refer IS 2:1960.
• Manufacturer details and regional IS offices are provided for licensing and inquiries.

flowchart TD
    A[Taps] --> B[Mark Manufacturer's Name/Trade-mark]
    A --> C[Mark Nominal Size]
    A --> D{Optionally Mark ISI Certification Mark}
    D -->|If Licensed| E[ISI Mark]
    D -->|If Not Licensed| F[No ISI Mark]

This marking ensures traceability, size identification, and quality assurance per IS 1711.