Specification for Underground Fire Hydrant, Sluice Valve Type

IS 909: Scope - Key Specifications & Tables

Scope Summary:

• Specifies construction, dimensions, and materials for underground fire hydrants (sluice-valve type).
• Includes details on outlet threads, caps, chains, and surface boxes.
• Applies IS 2:1960 for rounding off numerical values.
• References related standards (Annex A).

Key Formulas & Specifications:

Dimensions & Threads:

• Outlet Thread: External round thread, 2 threads per 2.54 cm (approx. 8 TPI), per IS 4694.
• Tolerance:
  • ±2 mm for ≤15 mm dimensions
  • ±2 mm for 16-50 mm
  • ±5 mm for >50 mm
• Surface Box: Minimum weight 135 kg (Fig. 2 details).

Construction Notes:

• Outlet cap covers threads, attached by steel chain (≥3 mm diameter).
• All castings must be clean, burr-free, and sound.
• Bolts & nuts conform to IS 1367 (Part 14).

flowchart LR
  A[Body (C.I.)] --> B[Valve Seat (G.M.)]
  B --> C[Valve (G.M.)]
  C --> D[Spindle (Brass)]
  D --> E[Spindle Nut (G.M.)]
  A --> F[Outlet with External Thread]
  F --> G[Cap attached by Chain]
  A --> H[Drain Bolt (M.S.)]

For full details, refer to IS 909 clauses 2.54, 4.6, and associated figures.

Thickness of Thread (t) - IS 909 (Clause 5.7)

• Thread Thickness (t):
  [ t = 5.7^{+0}_{-0.4} \text{ mm} ] This means the thickness is nominally 5.7 mm with a tolerance of -0.4 mm.

Thread Dimensions (Clause 68.0)

• Crest Diameter:
  [ 82 - 2^{+0}_{-0} \text{ mm} ]
• Root Diameter:
  [ \leq 68.0 \text{ mm (max)} ]

Thread Specification (Clause 2.54)

• Thread Type: External round thread
• Pitch: 2 threads per 2.54 cm (i.e., 1 thread per 12.7 mm)
• Taper: 1 in 20 on each side (as per Fig. 1A)
• Standard: Threads conform to IS 4694, 32×6 mm pitch

Additional Notes

• Outlet caps fully cover threads and are attached by a steel chain (min 3 mm diameter) to prevent loss.
• All parts must be free from burrs and defects.
• Tolerances as per IS 2102:1962:
  • ±2 mm for dimensions ≤ 15 mm
  • ±2 mm for 16-50 mm
  • ±5 mm for > 51 mm

Summary Table for Thread Dimensions

If needed, I can provide a mermaid diagram illustrating the thread profile and dimensions. Would you like that?

IS 909 - General Requirements Summary

1. Rounding Off (IS 2:1960)

   • Final test or calculation values must be rounded as per IS 2 rules.
   • Retain the same significant figures as the specified standard value.

2. Hydrant Outlet Threads (Clause 2.54 & Fig. 3)

   • External round threads, 2 threads per 2.54 cm (approx. 8 TPI).
   • Thread details per IS 4694: 32 × 6 mm pitch.
   • Outlet cap covers threads, attached by steel chain ≥ 3 mm diameter, anti-corrosive treated.

3. Material Specifications for Hydrant Components

4. Dimensional Tolerances (IS 2102:1962)

   • ±2 mm for dimensions ≤ 15 mm
   • ±2 mm for 16 mm to 50 mm
   • ±5 mm for > 50 mm

5. Construction Notes

   • All parts must be burr-free, clean castings, no welding/repairs.
   • Flanged connections with bolts.
   • Cap not threaded, fits snugly.

flowchart TD
    A[Hydrant Body (C.I.)] --> B[Valve Seat (G.M.)]
    B --> C[Valve (G.M.)]
    C --> D[Spindle (Brass)]
    D --> E[Outlet with External Thread (IS 4694)]
    E --> F[Cap attached by Steel Chain]

This covers the **general

IS 909: Materials - Key Specifications & Tables

1. Material Specifications for Hydrant Components

2. Thread Details for Outlet

• External round thread with 2 threads per 2.54 cm (1 inch)
• Thread size example: 32 × 6 mm pitch (As per IS: 4694)
• Outlet cap covers threads completely and is

IS 909: Road Surface Box - Key Specifications & Details

• Material & Weight:

  • Made of Cast Iron (CI) as per IS 210-1978 FG-200.
  • Minimum weight: 135 kg.

• Dimensions & Construction (Fig. 2 reference):

  • Flange to suit reducer flange.
  • Cap: Not threaded, feather edge removed.
  • Cover embossed with letters "FH" and painted canary yellow (IS 5:1978, shade 309).
  • Complete hydrant painted fire red (IS 5:1978, shade 536).

• Bolts & Nuts: Carbon steel as per IS 1367 (Part 14):1984.

• Outlet:

  • Screwed type with external round threads (2 threads per 2.54 cm) as per IS 4694.
  • Outlet cap attached by steel chain (min 3 mm diameter) with anti-corrosive treatment.

• Tolerances (IS 2102:1962):

  Dimension Range (mm)	Tolerance (mm)
  Up to 15	+2
  16 to 50	±2
  Above 51	±5

• Material Table for Components:

  No.	Component	Material	IS Spec.
  1	Body	Cast Iron (CI)	IS 210-1972
  4	Valve	Gun Metal (GM)	IS 318-1981
  7	Spindle	Brass	IS 319-1989
  13	Cap	Cast Iron (CI)	IS 210-1978
  14	Chain	Galvanized MS	-

Summary Diagram (Road Surface Box Components)

graph TD
  A[Road Surface Box Body (CI)] --> B[Flange for Reducer]
  B --> C[Cover with "FH" embossing]
  C --> D[Cap (CI) -

IS 909: Construction and Dimensions Key Points

1. Outlet Threading:

• Outlet is screwed type with external round thread, 2 threads per 25.4 mm (1 inch).
• Thread taper: 1 in 20 on each side.
• Thread dimensions as per IS 4694, example: 32×6 mm pitch.
• Thread thickness tolerance: +0, -0.4 mm.

2. Material Specifications:

3. Tolerances (IS 2102:1962):

• ±2 mm for dimensions ≤ 15 mm.
• ±2 mm for 16 to 50 mm.
• ±5 mm for > 51 mm.

4. Surface Box:

• Minimum weight: 135 kg.
• For second sluice-valve, conform to IS 3950:1979.

5. Cap and Chain:

• Cap covers outlet thread fully.
• Chain diameter: minimum 3 mm steel stock or equivalent.
• Chain anti-corrosive treated.

Thread Dimension Summary (Example)

flowchart LR
    A[Hydrant Outlet] --> B[External Round Thread]
    B --> C[Attached to Flanged Pipe End]
    C --> D[Outlet Cap]
    D -->

IS 909 - Coating of Parts Other Than Sluice-Valve (Clause 8)

• Cleaning: All cast iron parts must be thoroughly cleaned immediately after casting and before machining.
• Coating Composition: Dip parts in a bituminous-based bath (per IS 158:1981).
• Bath Temperature: Maintain between 143°C and 166°C.
• Coating Properties: Composition proportions must ensure properties as per Clause 8.3 (not detailed here).
• Purpose: Prevent rusting before machining or further processing.

Additional Specifications

Thread Details (Clause 2.54 & Fig. 3)

• Thread Type: External round thread with 2 threads per 2.54 cm (approx. 10 TPI).
• Chain: Steel chain min. 3 mm dia, anti-corrosive treated, attached to cap and outlet.
• Finish: Burr-free, sound castings without repairs or welding.

Summary Diagram (Coating Process)

flowchart LR
    A[Casting] --> B[Cleaning]
    B --> C[Dip in Bituminous Bath]
    C --> D[Coating Formation]
    D --> E[Machining / Further Processing]

Note: For detailed coating composition and properties, refer to IS 158:1981 and Clause 8.3 of IS 909.

IS 909 — Performance Requirements Summary

IS 909 focuses on valve performance, including Valve Seat Tightness Test as a key performance criterion.

Key Performance Requirement:

• Valve Seat Tightness Test: Ensures no leakage past the valve seat under specified pressure conditions.

General Guidelines:

• Test results must be rounded per IS 2:1960 rules, maintaining the same number of significant digits as specified values.
• Compliance is based on final observed/calculated test values.

Typical Valve Seat Tightness Test Parameters (from industry practice):

Notes:

• Refer to Annex A of IS 909 for related Indian Standards.
• For detailed formulas or leakage criteria, refer to related IS codes on valves (e.g., IS 5312).

flowchart TD
    A[Valve] --> B[Valve Seat]
    B --> C{Tightness Test}
    C -->|Pass| D[Valve Seat Tight]
    C -->|Fail| E[Leakage Detected]

Summary: IS 909 mandates valve seat tightness under pressure, with test results rounded per IS 2:1960. Check Annex A for adjunct standards.

IS 909: Criteria for Acceptance - Key Points

• Rounding Off Values: Final test or analysis results must be rounded per IS 2:1960 rules, retaining the same significant figures as the specified standard values.

• Stop Valve Testing (Clause 1.4):

  • Valve must be fully closed by screwing down the spindle.
  • Apply hydrostatic pressure of 1.4 MN/m² (14 bar) on the valve inlet.
  • No leakage is allowed through the valve or seat.

• Hydrant Testing (Clause 11):

  • Each hydrant must undergo tests as prescribed in IS 909.
  • Acceptance is based on compliance with all specified performance criteria.

• Annex A References:

  • Additional relevant Indian Standards provide supplementary requirements and testing methods.

Summary Table: Stop Valve Hydrostatic Test

flowchart TD
    A[Close Stop Valve] --> B[Apply 1.4 MN/m² Pressure]
    B --> C{Leakage?}
    C -- No --> D[Valve Accepted]
    C -- Yes --> E[Valve Rejected]

This ensures valves and hydrants meet safety and performance standards before acceptance.

IS 909 - Marking of Fire Hydrants (Clause 12.1 & 12.2.1)

• Mandatory Marking on each hydrant:

  • Manufacturer's name or trade-mark
  • Year of manufacture

• Optional Marking:

  • Hydrant may also carry the Standard Mark as per Clause 12.2.1

Related Specifications & Materials (Annex A)

Thread Specification (Clause 2.54)

• Outlet threads: External round thread, 2 threads per 2.54 cm (approx. 8 TPI)
• Thread standard: As per IS 4694
• Outlet cap: Covers threads, attached by chain for anti-loss

Dimension Tolerances (IS 2102:1962)

Summary Diagram of Marking & Components

graph TD
  A[Fire Hydrant] --> B[Marking]
  B --> B1[Manufacturer's Name/Trade-mark]
  B --> B2[Year of Manufacture]
  B --> B3[Standard Mark (optional)]
  A --> C[Components]
  C --> C1[Body (IS 210)]
  C --> C2[Outlet (IS 318)]
  C --> C3[Spindle (IS 319)]
  C --> C4[Washer (IS 937)]
  C --> C5[Chain (Galvan

IS 909: Referenced Indian Standards - Key Points

IS 909 refers to multiple Indian Standards essential for materials and components in fire-fighting equipment. These are listed in Annex A and include:

Additional Notes:

• These standards cover material specifications, fasteners, gaskets, coatings, and accessories used in fire-fighting equipment.
• The Standard Mark may be used for marking hydrants (Clause 12.2.1).
• For rounding off values, IS 2:1960 rules apply.

Summary Diagram of Referenced Standards

graph LR
A[IS 909 Fire Fighting Equipment]