Drafting stools-Specification

IS 4205: Scope Summary

• Scope: Specifies requirements for materials, sizes, construction, finish, and testing of stools/chairs used with drafting and reference tables.
• Applies to design and quality control of such seating furniture.
• Ensures comfort, durability, and safety in use with drafting/reference tables.

Key Specifications:

Rounding Off:
Final test values must be rounded as per IS 2:1960, maintaining the same significant figures as specified.

flowchart LR
    A[Materials] --> B[Size]
    B --> C[Construction]
    C --> D[Finish]
    D --> E[Testing]
    E --> F[Compliance with IS 4205]

This ensures stools/chairs meet functional and safety standards for drafting/reference table use.

IS 4205: Referenced Indian Standards (Annex A Summary)

IS 4205 relies on several Indian Standards as essential adjuncts, mainly covering materials, welding, coatings, and furniture testing. Key referenced IS include:

Important Notes:

• Rounding off: Follow IS 2:1960 for rounding test results to the same significant figures as specified.
• Marking: All stools must be marked to identify the manufacturer (Clause 11.1).
• Standard Mark: Products conforming to these standards carry the BIS Standard Mark, ensuring quality and conformity.

Summary Diagram of IS 4205 Referenced Standards

graph TD
  A[IS 4205] --> B[Paints & Finishes]
  A --> C[Steel & Aluminium Materials]
  A --> D[Welding Codes]
  A --> E[Furniture Testing]

  B --> IS110[IS 110, IS 151, IS 348]
  C --> IS513[IS 513, IS 1079, IS 7138]
  D --> IS814[IS 814 Part 2, IS 816, IS 819, IS 1278]
  E --> IS5416[IS 5416]

This ensures comprehensive compliance with materials,

IS 4205: Key Material Specifications

Aluminium Tubes (Clause 3.2)

• Must conform to IS 1285:1975 Designations:
  • 62400, 63400, or 65032
• Alternative tubes allowed with minimum properties:
  • Tensile Strength (Min): As per IS 1285
  • Elongation (Min): On 50 mm gauge length (specific values per designation)

Aluminium Sheets (Clause 3.1)

• Shall conform to IS 737:1986
• Alloy Designations: NS3, NS4, 31500 to 40800
• Condition: H2

Mild Steel Sheets (Clause 3.5)

• Shall conform to either:
  • IS 513:1986 or
  • IS 1079:1988

Metal Components (Clause 7.1)

• Follow relevant IS standards for metal components used in construction (refer to IS 4205 for detailed requirements).

Summary Table

For detailed mechanical properties, refer to respective IS standards mentioned.

IS 4205: Dimensions and Tolerances for Drafting Stools

Key Dimensions (Clause 4.1 & Fig. 1)

• All dimensions are in millimeters.
• The angle tolerance is implicit within the 95°–105° adjustable range.
• Final measured values should be rounded per IS 2:1960 rules.

Material Specification

• Wood as per IS 399:1963 for furniture.

Summary Diagram of Adjustable Stool Dimensions

graph TD
    A[Seat Reference Plane]
    B[Backrest Reference Plane]
    C[Footrest Detail]
    A -->|Adjustable Seat Height ≤ 700 mm| D[Seat Top Diameter 350 mm]
    B -->|Backrest Height 150-200 mm| E[Adjustable Backrest Height 225-325 mm]
    B -->|Angle 95°-105°| F[Backrest Centerline]
    C -->|Footrest Height 430 mm| G[Footrest Length 370 mm]

Use ±5 mm tolerance for all linear dimensions to ensure compliance with IS 4205.

IS 4205: Key Construction Specifications for Stools/Chairs

• Materials:

  • Aluminium tubes must conform to IS 1285:1975 (Designation 62400, 63400, or 65032).
  • Minimum tensile strength and elongation on 50 mm gauge length are specified (refer IS 1285 for exact values).
  • Wood used shall comply with IS 399:1963 (suitable furniture-grade timber).

• Dimensions & Tolerances:

  • Clause 4 covers dimensions and tolerances but requires reference to the detailed tables in the standard.
  • Typical dimensions relate to seat height, width, and backrest height suitable for drafting/reference tables.

• Finish & Construction:

  • Purchaser must specify color, finish, and any alternative construction methods at order time (Clause 9.1).
  • Surface finish must ensure durability and aesthetic suitability.

Aluminium Tube Properties (per IS 1285)

(Exact values depend on designation)

Summary Diagram of Construction Elements

graph LR
A[Materials] --> B[Aluminium Tubes (IS 1285)]
A --> C[Wood (IS 399)]
D[Dimensions & Tolerances] --> E[Seat Height, Width, Backrest]
F[Finish & Color] --> G[Specified by Purchaser]

For detailed dimensions and test methods, refer to the full IS 4205 standard text.

Welding and Assembly per IS 4205

• Clause 6.1: Assembly of components shall be by welding.

• Welding Methods (Clause 6.1.1):

  • Gas welding → IS 1323:1982
  • Arc welding → IS 816:1969
  • Spot welding → IS 819:1957

• Aluminium Welding (Clause 6.1.2):

  • Follow IS 2812:1964 for aluminium parts.

• Electrodes (Clause 3.3):

  • Gas welding electrodes → IS 1278:1972
  • Arc welding electrodes → IS 814 (Part 2):1974
  • Spot welding electrodes → IS 4972:1968

Key Specifications Summary

Important Notes:

• Welding procedures must comply with the relevant IS codes for quality and safety.
• Electrode selection is critical for weld strength and durability.
• For detailed welding parameters (current, voltage, speed), refer to the respective IS codes mentioned.

flowchart LR
    A[Components] --> B[Welding Assembly]
    B --> C{Welding Type}
    C --> D[Gas Welding (IS 1323)]
    C --> E[Arc Welding (IS 816)]
    C --> F[Spot Welding (IS 819)]
    D --> G[Electrodes IS 1278]
    E --> H[Electrodes IS 814]
    F --> I[Electrodes IS 4972]
    B --> J[Aluminium Welding (IS 2812)]

IS 4205: Surface Treatment and Finish - Key Points

• Preparation (Clause 7.1.1):
  Remove dents, burrs, sharp edges → Pickle → Scrub → Rinse to eliminate grease, rust, scale.

• Mild Steel Treatment (Clause 7.1.2):

  • Phosphating per IS 3618:1966
  • Followed by primer coat (e.g., red oxide)
  • Use putty for surface filling as per IS 110:1988

• Aluminium Treatment (Clause 7.1.4):

  • Anodizing optional, if purchaser requires
  • Must conform to Grade AC 25 of IS 1868:1982

• Order Specification (Clause 9.1):
  Purchaser must specify:

  • Colour and finish
  • Alternative construction/finish methods if any

Summary Table

flowchart LR
    A[Component] --> B[Remove dents, burrs, sharp edges]
    B --> C[Pickling]
    C --> D{Material?}
    D -->|Mild Steel| E[Phosphating (IS 3618)]
    E --> F[Primer coat (red oxide)]
    F --> G[Putty filling (IS 110)]
    D -->|Aluminium| H[Anodizing (IS 1868 Grade AC 25)]

This ensures corrosion resistance and desired finish quality as per IS 4205.

IS 4205: Packaging Specifications (Clause 8.1)

• Objective: Prevent damage to all component parts during transit.
• Requirement: Components must be packed securely to avoid mechanical damage, corrosion, or deformation.
• Packaging Guidelines:
  • Use protective materials (e.g., cushioning, anti-corrosive wraps).
  • Ensure tight and stable packing to prevent movement.
  • Label packages clearly for handling instructions.

Additional Notes:

• No explicit formulas or tables are provided in IS 4205 for packaging.
• Packaging design should consider:
  • Weight and fragility of components.
  • Transportation mode and duration.
  • Environmental conditions (humidity, temperature).

Summary Table for Packaging Considerations

Tip: Follow IS 4205 Clause 8.1 strictly and supplement with good engineering packaging practices for safe delivery.

IS 4205 - Information to be Supplied by the Purchaser (Clause 9)

The purchaser must provide clear details with the order to ensure correct manufacture and delivery:

• Colour and Finish: Specify exact colour shade and surface finish required.
• Alternative Methods: If multiple construction or finishing methods are allowed, clearly state the preferred choice.

Additional Notes:

• Packing (Clause 8.1): Components must be packed to avoid damage during transit.
• Rounding Off (per IS 2:1960): Test values should be rounded to the same number of significant digits as specified in the standard.
• Reference Standards: Annex A lists related Indian Standards necessary for compliance.

Summary Table for Purchaser Information

This ensures clarity in orders, reducing errors and ensuring compliance with IS 4205.

IS 4205: Performance Requirements and Tests for Stools/Chairs

Key Specifications:

• Strength Requirements (Clause 10.1):

  • Stools must pass static strength and fatigue strength tests as per IS 5416 (Part 1):1988, specifically Test Level 4 from Table 2 of that standard.
  • Passing criteria: No defects observed after testing.

• Rounding Off Results (General):

  • Final test or analysis values must be rounded according to IS 2:1960 rules.
  • Number of significant figures retained should match the specified value in IS 4205.

Reference Standards:

• IS 5416 (Part 1):1988 — Details static and fatigue strength testing procedures and levels.
• IS 2:1960 — Rules for numerical rounding.

Summary Table: Test Level 4 (from IS 5416 Part 1:1988)

flowchart LR
    A[Start: Stool Sample] --> B[Static Strength Test]
    B -->|No Defects| C[Fatigue Strength Test]
    C -->|No Defects| D[Pass]
    B -->|Defects| E[Fail]
    C -->|Defects| E

For detailed load values and cycle counts, refer to IS 5416 (Part 1):1988 Table 2.

IS 4205 - Marking of Stools (Clause 11.1)

• Marking Requirement:
  All stools must bear a suitable mark identifying the manufacturer.

• Purpose:
  Ensures traceability and accountability of the product.

• Standard Mark Use:
  Governed by the Bureau of Indian Standards (BIS) Act, 1986.
  The Standard Mark certifies compliance with IS requirements and quality control.

• Additional References:
  Related IS standards for materials and processes (e.g., IS 513 for steel sheets, IS 814 for welding electrodes) are listed in Annex A for comprehensive compliance.

Summary Table for Marking (Clause 11.1)

Note on Rounding (IS 2:1960)

Test results must be rounded off as per IS 2:1960 rules, maintaining the same significant digits as specified.

flowchart TD
    A[Manufacturing] --> B[Marking Manufacturer's ID]
    B --> C[Quality Control & Inspection]
    C --> D[Product Traceability]
    D --> E[Compliance with IS 4205]

In essence: Ensure every stool is clearly marked with the manufacturer's ID to comply with IS 4205 and BIS quality assurance.