metal chairs for office purposes Specification, Part 2: Revolving and tilting

IS 3499 Part 2 - Scope & Key Specifications

• Scope: Specifies requirements for steel chairs including dimensions, materials, and welding standards.
• Rounding off results: As per IS 2-1960, test results must be rounded to the same number of significant figures as the specified values.

Key Dimensions (Clause 3.1.4 - Table 3)

Related Specifications Referenced

• Filler rods and wires for gas welding
• Covered electrodes for metal arc welding (structural steel)
• Resistance spot-welding electrodes
• Steel tubes for furniture
• Slotted countersunk head screws
• Commercial timber classification and distribution

These ensure material compatibility and structural integrity for steel furniture.

flowchart LR
    A[Steel Chair Design] --> B[Dimensions]
    B --> C[Height: 785 mm]
    B --> D[Width incl. arm rests: 535 mm]
    A --> E[Materials & Welding]
    E --> F[Filler rods & wires]
    E --> G[Electrodes for arc welding]
    E --> H[Spot-welding electrodes]

Summary: IS 3499 Part 2 defines minimum chair dimensions and welding/material standards to ensure quality and safety of steel chairs.

IS 3499 Part 2 (1985) - Materials Key Specifications

1. Mild Steel Sheets

• Shall conform to Grade 0 of
  • IS 513:1973 or
  • IS 1079:1973

2. Aluminium Tubes

• Shall conform to IS Designation 62400, 63400, or 65032 of
  • IS 1285:1975

3. Minimum Overall Dimensions of Chairs (Clause 3.1.4)

4. Metal Components (Clause 6.1)

• Metal parts must comply with relevant IS standards for welding and fabrication, including:
  • Filler rods and wires for gas welding
  • Covered electrodes for metal arc welding (IS Part 1)
  • Resistance spot-welding electrodes

Summary Table of Material Standards

Note: For detailed welding specifications and metal component fabrication, refer to respective IS codes mentioned above.

flowchart TD
    A[Materials] --> B[Mild Steel Sheets]
    A --> C[Aluminium Tubes]
    A --> D[Welding Consumables]
    B --> E[IS 513:1973 Grade 0]
    B --> F[IS 1079:1973 Grade 0]
    C --> G[IS 1285:1975 (62400, 63400, 65032)]
    D --> H[Filler rods & wires]
    D --> I[Covered electrodes]
    D --> J[Resistance spot-welding electrodes]

IS 3499 Part 2 (1985) - Chair Dimensions (Clause 3.1.4)

Key Points:

• These are minimum overall dimensions for chairs.
• Dimensions ensure ergonomic comfort and standardization.
• Width includes arm rests for proper clearance.
• Rounding of dimensions should follow IS 2-1960 rules.

Additional Notes:

• Aluminium tubes used in chair frames must conform to IS 1285-1975 (IS Designations 62400, 63400, or 65032).
• Welding and finishing specifications refer to relevant IS codes for electrodes, filler rods, and surface polish.

Summary Table for Chair Dimensions

flowchart TD
    A[Chair Dimensions] --> B[Overall Height: 785 mm]
    A --> C[Overall Width (incl. arm rests): 535 mm]
    A --> D[Material: Aluminium Tubes per IS 1285-1975]
    A --> E[Welding & Finishing per relevant IS specs]

This ensures chairs meet ergonomic and manufacturing standards per IS 3499 Part 2.

IS 3499 Part 2 - Components for Metal Chairs

Key Specifications from IS 3499 Part 2:

1. Metal Components (Clause 6.1)

• Metal chairs are assembled from components detailed in Clauses 4.1 to 4.8.
• Components include frames, legs, armrests, seat and back supports, and welded joints.
• Welding should conform to relevant IS standards for filler rods, electrodes, and welding processes.

2. Minimum Dimensions (Clause 3.1.4 - Table 3)

3. Assembly & Welding Specifications

• Use filler rods and wires as per IS specifications for gas welding.
• Covered electrodes per IS standards for metal arc welding.
• Resistance spot-welding electrodes as per IS specs.
• All joints must be strong and finished smoothly for durability.

4. Rounding Off Test Results (Clause 0.3)

• Final test values must be rounded per IS 2:1960, maintaining significant figures as per the standard.

Summary Table: Chair Components & Dimensions

flowchart TD
    A[Metal Components] --> B[Frame]
    A --> C[Legs]
    A --> D[Armrests]
    A --> E[Seat & Back Supports]
    A --> F[Welded Joints]
    F --> G[Gas Welding (IS standards)]
    F --> H[Arc Welding (IS standards)]
    F --> I[Spot Welding (IS standards)]

This ensures compliance with IS 3499 Part 2 for durable, dimensionally accurate metal chairs.

IS 3499 Part 2: Welding and Assembly Key Points

• Assembly Methods (Clause 5.1):
  Components can be joined by welding, bolting, or screwing.

• Welding Standards:

  • Aluminium parts welding: As per IS 2812-1964.
  • Gas welding: Follow IS 1323-1966.
  • Arc welding: Follow IS 816-1969.
  • Spot welding: Follow IS 819-1957.

• Electrodes (Clause 2.2):

  • Gas welding electrodes: IS 1278-1972.
  • Arc welding electrodes: IS 814 (Part 1)-1974.
  • Spot welding electrodes: IS 4972-1968.

Typical Welding Parameters (from IS 816-1969 for Arc Welding):

Assembly Considerations:

• Ensure clean, oxide-free surfaces before welding (especially aluminum).
• Use correct electrode type as per IS standards for compatibility and strength.
• Follow recommended welding sequences to minimize distortion.

flowchart LR
    A[Components] --> B{Assembly Method}
    B --> |Welding| C[Gas / Arc / Spot Welding]
    B --> |Bolting| D[Bolted Joints]
    B --> |Screwing| E[Screwed Joints]
    C --> F[Use IS Standards for Welding & Electrodes]

Summary: Follow IS codes for welding methods and electrodes, ensure proper assembly technique, and maintain quality control for durable joints.

IS 3499 Part 2 (1985) - Surface Treatment and Finishing Key Points

1. Surface Preparation

• Phosphating Treatment: Immediately after pickling, apply phosphate coating per Class C of IS: 5618-1966.
• Application process per IS: 6005-1970.
• Putty for filling surfaces must conform to IS: 110-1968.
• Aluminium primer per IS: 5660-1970.

2. Paint Coats (Clause 6.1.3)

• Finish coat with enamels conforming to:
  • IS: 151-1950
  • IS: 2932-1974
  • IS: 2933-1975

3. Testing Requirements

Summary Diagram of Surface Treatment Process

flowchart TD
    A[Pickling] --> B[Phosphating Treatment (IS:5618)]
    B --> C[Putty Application (IS:110)]
    C --> D[Primer Application (Aluminium Primer IS:5660)]
    D --> E[Enamel Paint Coating (IS:151, 2932, 2933)]
    E --> F[Testing: Corrosion & Adhesion (IS:101)]

Use these standards and tests to ensure durable, corrosion-resistant surface finishing of mild steel structural components.

IS 3499 Part 2 - Testing Requirements Summary

• Rounding Off Results (Clause 0.3):
  Test results must be rounded as per IS 2-1960.

  • Retain the same number of significant figures as the specified value.
  • Ensures uniformity in reporting test outcomes.

• Pressure Test (Clause 7.2):

  • Samples: Mild steel plates, 0.315 mm thickness.
  • Preparation: As per Clause 6 (surface finish and dimensions).
  • Test Method: Follow IS 101-1964, Clause 15.2.
  • Acceptance Criteria: No visible metal surface exposure upon separation after the test.

Key Reference Table: Pressure Test Sample Thickness

Notes:

• IS 101-1964 Clause 15.2 details the pressure test procedure (usually involves hydraulic or pneumatic pressure to check joint integrity).
• Ensure test samples conform strictly to preparation requirements for valid results.

flowchart TD
    A[Prepare Sample] --> B[Pressure Test per IS 101-1964, 15.2]
    B --> C{Metal Surface Visible?}
    C -- No --> D[Test Passed]
    C -- Yes --> E[Test Failed]

For detailed test procedures, refer to IS 101-1964 and IS 2-1960 for rounding rules.

IS 3499 Part 2 - Packaging Specifications Summary

• Clause 8.1: All component parts must be packed to prevent damage during transit.
• No detailed formulas or tables for packaging are specified in the standard.
• Packaging should ensure protection against mechanical damage, corrosion, and environmental effects.
• Typical packaging considerations (engineering best practice):
  • Use cushioning materials (foam, bubble wrap) around delicate parts.
  • Employ rigid boxes or crates sized to the component dimensions.
  • Include moisture barriers or desiccants if corrosion is a risk.
  • Secure components to prevent movement inside packaging.

Example Packaging Checklist (based on IS 3499 Part 2 and engineering practice)

Summary Diagram of Packaging Concept

graph LR
A[Component Parts] --> B[Protective Wrapping]
B --> C[Rigid Outer Packaging]
C --> D[Labeling & Handling Instructions]
C --> E[Moisture Control Measures]

Note: For precise dimensions of components like chairs (Clause 3.1.4), refer to the dimensional table in IS 3499 Part 2. Packaging must accommodate these sizes.

IS 3499 Part 2 - Information to be Supplied by Purchaser

Key Information Purchaser Must Provide (Clause 9.1):

• Type of seat (e.g., wooden, cushioned, metal)
• Type of back (e.g., fixed, adjustable)
• Castor unit requirement (yes/no and type if needed)
• Colour of finish
• Alternative construction or finish methods, if any

Marking Requirement:

• All metal chairs must be marked with a manufacturer’s identification.

Minimum Overall Dimensions (Clause 3.1.4):

Packaging (Clause 8.1):

• Components must be packed to prevent damage during transit.

Summary Table:

This ensures clear communication and compliance with IS 3499 Part 2 for chair manufacturing and supply.