Functional Requirements for 680-1/Min Trailer Pump For Fire Brigade Use

IS 943 - Scope & Key Specifications Summary

The standard covers fire fighting appliances and their recommended equipment for operation and maintenance.

Key Equipment & Quantities (Appendix A, Clause 0.2.1 & 4.5):

Notes:

• Instruction manuals with illustrated spare parts list are mandatory (Clause 6.1).
• Equipment not part of the appliance but required for operation are listed for guidance.
• Rounding off test results follows IS: 2-1960 (Clause 0.3).

Summary Diagram of Equipment Categories:

graph TD
  A[Fire Fighting Appliance] --> B[Mechanical Equipment]
  A --> C[Chemical Agents]
  A --> D[Tools & Accessories]
  B --> B1[Sledge Hammer, Jack Screw]
  C --> C1[Foam Compound, Branch Pipes]
  D --> D1[Oil/Petrol Cans, Funnels, Ropes, Hose Clamps]

This scope ensures the appliance is equipped with

IS 943 General Requirements Summary

Equipment List (Appendix A, Clause 0.2.1 & Table)

• Sledge hammer: 6.5 kg (1 No.)
• Jack screw (lifting): 6 tonne (1 No.)
• Oil can: 2 litres (1 No.)
• Petrol can: 9 litres (1 No.)
• Oil & Petrol filling funnels: 1 No. each
• Foam compound: 20 litres drum (5 Nos.) [IS: 4989-1974]
• Foam making branch pipe FB-2: 1 No. [IS: 2097-1969]
• Two-way suction collecting head: 1 No. [IS: 904-1965]
• Universal branch pipe: 1 No. [IS: 2871-1974]
• Hydrant keys: 2 Nos. [IS: 910-1972]
• Ropes: Long line (30 m), Guy line (30 m), Lowering line (30 m), Short line (15 m)
• Hose clamps: 6 Nos. [IS: 5612 (Part I)-1973]

Rounding Off Values (Clause 0.3)

• Use IS 2-1960 rules for rounding.
• Maintain the same significant figures as specified values.

Key Notes:

• The standard covers material, design, workmanship, finish, and performance tests for 680 l/min trailer pumps.
• Equipment listed supports operational readiness and safety.
• Refer to respective IS codes for detailed specifications of each equipment.

graph LR
A[Fire Brigade Trailer Pump] --> B[Essential Equipment]
B --> C[Sledge Hammer 6.5 kg]
B --> D[Jack Screw 6 tonne]
B --> E[Oil & Petrol Cans + Funnels]
B --> F[Foam Compound & Branch Pipes]
B --> G[Hydrant Keys & Ropes]
B --> H[Hose Clamps]

This structure ensures compliance with IS 943 general requirements for fire brigade pumps.

IS 943: Pump Performance and Testing Key Points

Testing Conditions (Clause 4.3.3)

• Water temperature: 27 ± 2°C (substitute for 16.5°C)
• Atmospheric pressure: 760 mm Hg
• Rated outputs corrected for:
  • Output allowance:
    • -1% per 2.5°C rise in water temperature
    • -4% per 300 m elevation above sea level
    • Humidity: no deduction up to 75%, deduction above 75%
  • Lift allowance:
    • +30 cm per 300 m elevation
    • +1% per 2.5°C rise in water temperature

Pump Performance Table (Clause 4.3.4)

• Max speed: 4000 rpm impeller shaft
• All internal/external strainers fitted (except basket strainer)

Structural & Operational Requirements (Clause 4.3.2 & 4.3.5)

• Impeller dynamically balanced at max speed
• Casing withstands 1.5× shut-off pressure or 2× operating pressure (whichever higher)
• Continuous 4-hour run test at:
  • Rated output
  • 3 m lift
  • 0.7 MN/m² (7 kgf/cm²) pressure
• Engine oil temperature limits must be maintained

Formula Summary for Output Correction:

[ Q_{corrected} = Q_{rated} \times \left(1 - 0.01 \times \frac{T_{actual} - 27}{2.5} - 0.04 \times \frac{h}{300} \right) ]

Where:

• (Q) = output flow rate
• (T_{actual}) = actual water temperature (°C)
• (h) = elevation above mean sea level (

IS 943 Key Points for Trailer Frame and Suspension

Trailer Frame & Suspension (Clause 4.7.1, 4.7.8)

• Springs: Use two semi-elliptic leaf springs as per IS: 1135-1973.
• Tyres: Heavy-duty tyres, 6:00x16 size, 6 ply rating.
• Mounting: Pumping unit mounted to keep the center of gravity low for stability.
• Equipment Carrying: Provision per Appendix B for carrying specified equipment.

Towing Eye & Draw Bar (Clause 4.9, 4.9.2)

• Design must withstand a draw pull of 11 kN (1100 kgf) without overstress.
• Eye and housing must be robust and securely fixed to the chassis frame.

Typical Semi-Elliptic Leaf Spring Formula (IS 1135)

[ \sigma = \frac{6WL}{bt^2} ]

Where:

• (\sigma) = maximum bending stress in the spring
• (W) = load on the spring
• (L) = length of the spring
• (b) = width of the leaf
• (t) = thickness of the leaf

Summary Table

flowchart LR
    A[Trailer Frame] --> B[Semi-Elliptic Springs (IS:1135)]
    A --> C[Heavy Duty Tyres (6:00x16, 6 ply)]
    A --> D[Draw Bar & Eye (withstand 11 kN)]
    B --> E[Load Support & Shock Absorption]
    D --> F[Secure Fixing to Frame]

This ensures a durable, stable trailer frame with reliable suspension and towing capacity.

IS 943: Engine and Cooling System Key Points

Cooling System (Clause 4.1.2 & 4.3.2)

• Type: Indirect open circuit cooling system (water-cooled engine).
• Water Flow: Water discharged to waste after circulating through copper coils in a header tank.
• Water Supply: Fed from main centrifugal pump.
• Max Discharge: ≤ 30 l/min.
• Components: Header tank with copper coils, drain plug, and a cleanable filter operable during pump running.
• Temperature Control: Maintain engine temperature within manufacturer's recommended range.

Pump Performance (Clause 4.3.5)

• Test Duration: 4 hours continuous operation with engine cover closed.
• Pump Output: Rated output at 3 m lift and 0.7 MN/m² (7 kgf/cm²) pressure.
• Cooling Water: No replacement during test.
• Oil Temperature: Engine lubricating oil temperature must not exceed specified limits.

Summary Table

flowchart LR
    Pump --> HeaderTank[Header Tank with Copper Coils]
    HeaderTank --> Waste[Water to Waste ≤ 30 l/min]
    HeaderTank --> Filter[Cleanable Filter]
    HeaderTank --> Engine[Engine Cooling]

This ensures effective engine temperature control and pump reliability per IS 943.

IS 943: Accessories and Equipment Key Points

1. Equipment Lists (Appendices A & B)

• Appendix A: Recommended equipment for use with the appliance (Clause 0.2.1, 4.5)
• Appendix B: Equipment to be provided in trailer pump (Clause 6.3, 4.7.8)

2. Key Equipment from Appendix A (Sample Items)

3. Key Equipment from Appendix B (Trailer Pump)

IS 943 – Towing Eye and Drawbar Key Specifications

• Towing Eye Internal Diameter: 75 mm (Clause 4.9.1)
• Material: High-quality forged steel with minimum ultimate tensile strength of 630 MN/m² (63 × 10² kgf/cm²) or equivalent material.
• Shank: Adequately machined with proper radii at shoulders to avoid stress concentration.

Design Load Requirements:

• The towing eye housing and drawbar must safely withstand a draw pull of 11 kN (1100 kgf) without overstressing (Clause 4.9.2).

Shock Absorption:

• The shank must be mounted to absorb shocks in both forward (tow load) and backward (braking) directions.
• Compensation mechanism should ensure smooth towing at reasonable speeds on average roads (Clause 4.9.3).

Summary Table

flowchart LR
    A[Towing Eye] --> B[Shank with Radii]
    B --> C[Mounted in Housing]
    C --> D{Absorbs Shock?}
    D -->|Forward| E[Tow Load Cushioning]
    D -->|Backward| F[Brake Application Regulation]
    E & F --> G[Smooth Tow at Reasonable Speeds]

This ensures durability, safety, and comfort in towing operations as per IS 943.

IS 943: Stability and Safety Key Points

Stability (Clause 4.8.1)

• The trailer must remain stable on a 25° tilt from horizontal without overturning.
• Stability is checked with the trailer equipped and front supported in towing position.
• Overturning point must not be exceeded on tilting.

Safety & Performance (Clause 4.7.3)

• Fully laden trailer towed at 20 km/h:
  • Cross-country for 2 km
  • Tar road for 10 km
• Trailer must hold the road well; no axle distortion or wheel misalignment.

Equipment (Clause 4.7.8 & 6.5)

• Equipment per Appendix B must be carried on trailer.
• Essential tools:
  • Sledge hammer: 6.5 kg
  • Jack screw: 6 tonne capacity
  • Oil can (2 L), Petrol can (9 L)
  • Oil & petrol filling funnels

Stability Check Formula (General Engineering Knowledge)

[ \text{Overturning condition: } \tan \theta \leq \frac{B}{2h} ]

Where:

• (\theta = 25^\circ) (max tilt angle)
• (B =) track width (distance between wheels)
• (h =) height of center of gravity from ground

Ensure:

[ \frac{B}{2h} \geq \tan 25^\circ \approx 0.466 ]

Summary Table: Stability Parameters

flowchart LR
    A[Trailer Stability] --> B{Tilt Angle ≤ 25°?}
    B -- Yes --> C[No Overturning]
    B -- No --> D[Overturning Risk]
    C --> E[Safe for Towing]
    D --> F[Unsafe - Redesign Needed]

**Note

IS 943: Key Dimensions and Weight Specifications

• Overall Dimensions (Clause 2.2):

  • Length ≤ 3.3 m
  • Height ≤ 1.6 m (including spotlight)
  • Wheel track ≤ 1.4 m

• Mass (Clause 4.10):

  • Total mass of unit ≤ 750 kg (includes water, fuel, oil; excludes equipment in Appendix B)

• Equipment Weights (Clause 6.5):

  • Sledge hammer: 6.5 kg
  • Jack screw (lifting capacity): 6 tonnes
  • Oil can: 2 litres capacity
  • Petrol can: 9 litres capacity

• Additional Specifications:

  • Provisions for carrying equipment per Appendix B on trailer (Clause 4.7.8)
  • Specifications for foam compounds, foam-making branches, suction heads, branch pipes, keys, hose clamps, and leaf springs are referenced but detailed separately.

Summary Table

graph TD
A[Trailer Unit] --> B[Dimensions]
B --> C[Length ≤ 3.3m]
B --> D[Height ≤ 1.6m]
B --> E[Wheel track ≤ 1.4m]
A --> F[Mass ≤ 750kg]
A --> G[Equipment]
G --> H[Sledge hammer 6.5kg]
G --> I[Jack screw 6 tonnes]
G --> J[Oil can 2L]
G --> K[Petrol can 9L]

This concise summary aligns with IS 943 clauses for design and equipment specifications.

IS 943: Marking and Identification - Key Specifications

The code specifies standard equipment and their quantities for fire fighting appliances, ensuring uniformity and ease of identification:

Equipment List & Quantities (Selected Items from Clause 4.5, Appendix A)

Marking & Identification Requirements:

• Instruction Book: Must include operating and maintenance procedures with illustrated spare parts list (Clause 6.1).
• Standard Paint Colors: Ready mixed paints colors as per IS specifications for easy identification.
• Equipment Marking: Each item should be marked with its capacity, IS number, and manufacturer details for traceability.

Summary Diagram of Equipment Identification Flow:

flowchart TD
    A[Fire Appliance] --> B[Equipment List]
    B --> C[Sledge Hammer - 6.5 kg]
    B --> D[Jack Screw - 6 tonne]
    B --> E[Oil Can - 2 litres]
    B --> F[Petrol Can - 9 litres]
    B --> G[Instruction Book]
    G --> H[Operating Procedure]
    G --> I[Spare Parts List]
    B --> J[Marking & Paint Colors]

Note: For detailed marking dimensions or label

IS 943: Maintenance & Operation - Key Specifications

Essential Equipment (Clause 4.5 & Appendix A)

Maintenance & Operation Guidelines (Clause 6.1)

• Instruction Book: Must include detailed operating and maintenance procedures.
• Spare Parts List: Illustrated, itemized with reference numbers.
• Mass Limit: Complete unit mass ≤ 750 kg (incl. water, fuel, oil; excl. equipment).

Additional Notes

• Use specified paints and enamel for exterior protection.
• Follow IS codes for each equipment type (e.g., IS: 2878 for CO2 extinguishers).
• Regular inspection and lubrication using oil cans, grease guns.
• Use proper tools listed for maintenance (sledge hammer, jack screw, spanners).

Summary Diagram: Maintenance Equipment Setup

graph LR
A[Fire Appliance] --> B[Oil Can (2L)]
A --> C[Petrol Can (9L)]
A --> D[Sledge Hammer (6.5kg)]
A --> E[Jack Screw (6 tonne)]
A --> F[Foam Compound (20L drums

IS 943: List of Recommended Equipment for Trailer Pump

Key Equipment to be Provided in Trailer Pump (Appendix B, Clause 6.3)

Recommended Equipment for Use with Appliance (Appendix A, Clause 0.2.1)

• Fire extinguisher, CO2 type, 4.5 kg (IS: 2878-1976)
• Fire buckets (IS: 2546-1974)
• First aid box (for 10 persons)
• Rubber gloves (IS: 4770-1968)
• Fireman axe (IS: 926-1970)
• Shovels (IS: 274 Part I-1966)
• Pick axe, 1 kg (IS: 273-1973)
• Crow bar with chisel and claws, 1 m length (IS: 704-1968)
• Hand rip saw, 65 mm (IS: 5098-1969)
• Adjustable spanner, 30 cm (IS: 6169-1971)
• Fire hook (IS: 927-1964)
• Shears or bolt clippers (IS: 5200-1969)
• Asbestos gauntlets

Additional Equipment (Appendix B)

IS 943: Equipment to be Provided in Trailer Pump

Key Specifications (Clause 2.1)

• Pump capacity: ≥ 680 l/min at 0.7 MN/m² (7.0 kgf/cm²) pressure
• Drive: Internal combustion engine
• Mounting: Permanently on a trailer, pump at rear
• Mobility: Towable by a standard vehicle

Equipment List (Clause 4.7.8 & Appendix B)

Additional Accessories (Clause 6.2)

• Electric tail-light with number plate plug at front
• Essential tool kit for maintenance
• Headlight (≤ 150 mm diameter)

Summary Diagram of Trailer Pump Setup

graph LR
A[Internal Combustion Engine] --> B[Pump (≥680 l/min @ 7 kgf/cm²)]
B --> C[Suction Hose (100 mm)]
C --> D[Suction Strainer & Wrenches]
B --> E[Branch Pipes (63 mm)]
A --> F[Trailer Frame with Tail-light & Headlight]
F --> G[Tow Hitch for Vehicle]

This ensures compliance with IS 943 for trailer pumps used in firefighting or related applications.