Specification for 2-Way And 3-Way Suction Collecting Heads For Fire Fighting Purposes

IS 903: Scope - Key Specifications & Tables

Scope Summary:

• Covers delivery hose couplings of two sizes: 63 mm and 70 mm.
• Dimensions and tolerances are strictly defined (±0.5 mm where not specified).
• Applies to fire-fighting hose couplings and related fittings.

Key Dimensions (Clause 2.5 & 5.3)

*Note: For 70 mm size, B is reduced to 53 mm over 5 mm length at washer, then tapered smoothly.

Tolerances:

• ±0.5 mm unless otherwise specified.

Hydraulic & Deflection Test Requirements (Clause 2.5 & 62.7)

Rounding Off (General Rule)

• Follow IS 2:1960 for rounding numerical values.
• Retain the same number of significant figures as the specified value.

Referenced Indian Standards (Annex A)

• IS 291, 292, 304, 318, 617, 937, 1264 etc. for materials and coatings.
• IS 2643 for pipe thread dimensions.
• IS 1570 for wrought steels.

flowchart LR
    A[IS 903 Scope] --> B[Two Sizes: 63 & 70 mm]
    B --> C[Dimension Tolerances ±0.5 mm]
    B --> D[Hydraulic Test: 120-125 mm]
    B --> E[Deflection Test: 62-62.7 mm]
    A --> F[Material & Coating Standards]

IS 903 - References: Key Specifications and Tables

Rounding Off (Clause None)

• Follow IS 2:1960 for rounding numerical results.
• Retain the same significant digits as specified values.

Dimensional Tolerances

• Unless specified, tolerance = ±0.5 mm.
• Important for hose couplings, nozzles, and fittings.

Hydraulic Test Requirements (Clause 2.5, Table 7.3)

• Dimensions for Female Half Coupling (Size 63 & 70 mm):

  Size	A (ø)	B (ø)	C (ø)	D (ø)
  63	63	53 +0.00/-0.5	63	53 +0.00/-0.5
  70	70	60 +0.00/-0.5*	70	60 +0.00/-0.5

  *For size 70, B reduces to 53 mm over 5 mm length with smooth curve.

Parallel Threads (Clause 1.5)

• Threads per IS 2643 (Part 1), G 1 3/4 standard.
• Tolerance ±0.5 mm.

Referenced Indian Standards (Annex A)

• Material specs: Naval brass rods (IS 291), Leaded brass ingots (IS 292), High tensile brass (IS 304), Aluminium alloys (IS 617), Stainless steel wire (IS 6528), etc.
• Coating specs: Hard chromium (IS 1337), Zinc plating (IS 1573).

Summary Diagram: Hose Coupling Dimensions

graph LR
A[Size] --> B[A (ø)]
A --> C[B (ø)]
A --> D[C (ø)]
A --> E[D (ø)]
B -->|63 or 70| C
C -->|Tolerance ±0.5 mm| D

Use IS 2:1960 for rounding and IS 2643 for thread details. Tolerances are critical for interchangeability and performance.

IS 903: Workmanship and Finish - Key Points

• General Quality:

  • All fittings must exhibit good workmanship and finish.
  • Surfaces should be free from burrs, sharp edges, porosity, blowholes, scales, cracks, or other defects.
  • Forgings and castings must be sound and not repaired or filled to hide defects.
  • The water-way inside fittings must have a smooth finish.

• Material Specifications:

  • Aluminium alloys used shall be die cast conforming to IS 617 (Designations 4225, 4450, or 4600).
  • Exposed aluminium surfaces must have an anodized finish.
  • Threaded aluminium parts coated with molybdenum-based grease.
  • Steel castings should conform to Grade 1 or 4 of IS 3444:1987 (corrosion-resistant alloy steel).

• Dimensional Tolerances:

  • Unless otherwise specified, tolerance = ±0.5 mm.
  • Example dimensions for couplings (in mm):

*Note: For size 70, B is reduced to 53 mm over 5 mm length at washer, then transitions smoothly.

Summary Diagram of Workmanship Requirements

flowchart TD
    A[Start: Manufacturing] --> B[Check Material Quality]
    B --> C{Forgings & Castings}
    C -->|Sound, No Defects| D[Proceed]
    C -->|Defects Present| E[Reject or Recast]
    D --> F[Surface Finish]
    F -->|Smooth, No Burrs| G[Apply Coatings/Anodizing]
    F -->|Rough/Defective| E
    G --> H[Final Inspection]
    H -->|Meets

IS 903: Marking and Criteria for Conformity

Key Marking Requirements (Clause 4.1)

Each fitting shall be clearly and permanently marked with:

• Manufacturer's name and trade-mark
• Size (where applicable)
• Year of manufacture

Additionally, fittings may carry the Standard Mark (Clause 4.1.1), which assures compliance with the standard under BIS supervision.

Criteria for Conformity

• Test results should be rounded off as per IS 2:1960 maintaining the same significant figures as the specified values.
• Continuous quality control and inspection are enforced by BIS for license holders using the Standard Mark.

Tolerances & Testing (Clause 62.7)

• Dimensional tolerances where unspecified: ±0.5 mm
• Example: Deflection test requirements (Table 8.4) specify minimum and maximum deflections in mm.

Summary Table: Marking Information

flowchart TD
    A[Fitting] --> B[Mark Manufacturer Name & Trade-mark]
    A --> C[Mark Size]
    A --> D[Mark Year of Manufacture]
    A --> E{Optional}
    E --> F[Standard Mark (BIS)]

For detailed specifications on materials, coatings, and dimensions, refer to the annexed IS standards listed in IS 903 Annex A.

IS 903: Delivery Hose Coupling Key Specifications

1. Delivery Hose Coupling Components (Clause 5.1)

• Consists of Male Half Coupling and Female Half Coupling assembled with a washer.
• Refer to Fig. 1 & Fig. 2 for assembly details.

2. Dimensions & Tolerances (Clause 2.5)

• All dimensions in mm.
• General tolerance: ±0.5 mm where not specified.
• Hydraulic test requirements per Table 7.3 (not fully provided here).

3. Female Half Coupling Dimensions (Fig. 2 & Table)

• Note: For size 70, dimension B reduces to 53 mm for 5 mm length near washer, tapering smoothly after serration.

4. Male Half Coupling & Nozzle Spanner

• Male half coupling details per Fig. 2.
• Nozzle spanner size: 8 (Clause 2B).

Summary Diagram of Coupling Assembly

graph LR
  FH[Female Half Coupling]
  Washer[Washer]
  MH[Male Half Coupling]

  FH --> Washer --> MH

For detailed hydraulic test pressures and other fittings, refer to Table 7.3 and full IS 903 document.

IS 903: Branch Pipe Key Specifications & Formulas

• Shape & Dimensions:
  As per Clause 6.2, branch pipe shape and dimensions must conform exactly to Fig. 3 of IS 903. (Refer IS 903 Fig. 3 for detailed geometry.)

• Hydraulic Pressure Test:

  • Pressure = 2.1 MN/mm² (21 kgf/cm²)
  • Duration = 2.5 minutes
  • No leakage or sweating allowed (Clause 2.1).

• Washers for Branch Pipe:
  Use washers conforming to Type B of IS 937:1981 (Clause 5.2).

Typical Hydraulic Pressure Test Formula

[ P = \frac{F}{A} ]

Where:

• (P) = Test pressure (2.1 MN/mm²)
• (F) = Force applied
• (A) = Cross-sectional area of the branch pipe

Summary Table

flowchart LR
    A[Branch Pipe] --> B{Shape & Dimensions}
    B --> C[Fig. 3 (IS 903)]
    A --> D[Hydraulic Test]
    D --> E[Pressure: 2.1 MN/mm²]
    D --> F[Duration: 2.5 min]
    D --> G[No Leakage/Sweating]
    A --> H[Washer]
    H --> I[Type B (IS 937:1981)]

For precise dimensions and detailed drawings, always refer to Fig. 3 of IS 903 directly.

IS 903 Nozzles – Key Specifications & Tables

1. Nozzle Sizes (Clause 7.2)

• Permissible diameters: 6, 12, 15, 20, 25, 30 mm
• Dimensions as per Fig. 4 (not shown here)
• Tolerance: ±0.5 mm (where not specified)

2. Hydraulic Pressure Test (Clause 2.1 & 2.5)

• Test pressure: 2.1 MN/mm² (21 kgf/cm²)
• Duration: 2.5 minutes
• Acceptance: No leakage or sweating allowed

3. Coupling Dimensions (Clause 2.5, Table 7.3)

• Note: For ø70, B reduces to 53 mm over 5 mm length at washer, tapering smoothly.

4. Nozzle Spanner (Clause 8.1)

• Material: Steel Grade 35C4 or 40C8 as per IS 1570 (Part 2/Sec 1):1979

graph LR
A[Nozzle Sizes] --> B[6,12,15,20,25,30 mm]
B --> C[Dimension Fig.4]
D[Hydraulic Test] --> E[2.1 MN/mm² for 2.5 min]
E --> F[No leakage allowed]
G[Coupling Dimensions] --> H[Table 7.3]
H --> I[Size 63 & 70 mm details]
J[Nozzle Spanner] --> K[Grade 35C4 or 40C8 Steel]

For detailed dimensional drawings, refer to Fig. 4 and Table 7.3 in IS 903.

IS 903 - Nozzle Spanner Key Points

Material Specification (Clause 8.1)

• Steel Grade: 35C4 or 40C8 as per IS 1570 (Part 2/Sec 1):1979

Nozzle Sizes (Clause 7.2)

• Standard nozzle sizes: 6, 12, 15, 20, 25, 30 mm
• Dimensions conform to Fig. 4 (not provided here)

Dimensional Tolerances (Clause 2.5)

• General tolerance: ±0.5 mm where not specified

Deflection Test (Clause 8.4)

• Spanner fitted on hexagon bar of correct size
• Apply 35 kg weight at 17 cm from centerline (horizontal handle)
• No permanent deflection or damage allowed

Additional Notes

• Parallel threads as per G 13/4 of IS 2643 (Part 1)
• All dimensions in millimeters

Summary Table: Nozzle Sizes and Test Load

flowchart LR
    A[Nozzle Spanner] --> B[Material: Steel 35C4/40C8]
    A --> C[Nozzle Sizes: 6-30 mm]
    A --> D[Deflection Test]
    D --> E[Apply 35 kg at 17 cm]
    E --> F[No permanent deflection]

For detailed dimensions, refer to Fig. 4 of IS 903 and IS 1570 for steel grades.

IS 903 - List of Referred Indian Standards (Annex A)

This annex provides key Indian Standards referenced in IS 903 related to materials and specifications for fire fighting equipment:

Additional Notes:

• All dimensions in mm.
• Tolerance ±5 mm unless specified.
• These standards cover material specifications, coatings, dimensions, and mechanical properties critical for fire fighting equipment manufacturing and testing.

This list ensures compatibility and quality compliance across components used in fire safety systems.

IS 903 - Foreword: Key Points, Tables & Specifications

Foreword Overview:

• IS 903 relates to specifications for fire fighting equipment components.
• It references multiple Indian Standards (IS) for materials and coatings.
• The standard includes dimensional tolerances, test requirements, and committee composition.

Important Specifications & Tables:

1. Dimensional Tolerances

• Unless otherwise specified, tolerance = ±0.5 mm.
• Applies to all critical dimensions in couplings, nozzles, and spanners.

2. Coupling Dimensions (Clause 2.5, Table 7.3)

Key Notes:

• Final test results must be rounded per IS 2:1960 rules.
• Hydraulic and deflection test requirements are specified (e.g., Clause 62.7).
• Nozzle spanner and cam tooth details are dimensioned precisely for compatibility.

Committee Composition:

• Includes representatives from Ministry of Home Affairs, Railways, Defence, Fire Services, and industry experts ensuring comprehensive standardization.

flowchart LR
    A[IS 903 Standard] --> B[Material Specs (Brass, Steel, Aluminium)]
    A --> C[Dimensional Tolerances ±0.5 mm]
    A --> D[Coupling Dimensions Table]
    A --> E[Test Requirements (Hydraulic, Deflection)]
    A --> F[Committee for Fire Fighting Equipment]

Summary: IS 903 sets strict dimensional, material, and test criteria for fire fighting couplings and accessories, ensuring interchangeability and reliability. Use the tables and tolerances for precise manufacturing and testing.