steel bookcases

IS 7761: Scope - Key Specifications & Dimensions

Scope: Covers steel book cases with defined dimensions, materials, and quality requirements.

1. Dimensions (Clause 3.1)

• Dimensions are overall external sizes.
• Refer Fig. 1 in IS 7761 for detailed layout.

2. Material & Fabrication

• Back Sheet Thickness: Minimum 1.0 mm steel sheet, full width of cabinet (Clause 4.3).
• Surfaces must be free of burrs, dents, and sharp edges (Clause 6.1.1).
• Components are pickled, scrubbed, and rinsed to remove contaminants.

3. Marking (Clause 10.1.1)

• May bear ISI Certification Mark ensuring compliance with IS standards and quality control.

4. Units

• All dimensions and properties use SI units (metre, kilogram, second, etc.).
• Pressure/stress: Pascal (Pa = N/m²)
• Force: Newton (N = kg·m/s²)

Summary Diagram: Steel Book Case Structure

graph TD
    A[Top Panel] --> B[Side Panels]
    B --> C[Bottom Panel]
    C --> D[Back Sheet (1.0 mm thick)]
    B --> E[Shelves]
    style D fill:#f9f,stroke:#333,stroke-width:2px

References

• IS 7761 - 1983
• Related IS codes for materials and welding practices.

This concise scope ensures uniformity in size, material quality, and marking for steel book cases under IS 7761.

Key Specifications & Formulas for Materials (IS 7761)

1. Material Thickness & Quality

• Back Sheet Thickness: Minimum 1.0 mm steel sheet, free from burrs or dents.
• Steel Grade for Rounds & Flats: Mild steel grade Fe 310-0 (St 32-0) as per IS:1977-1975, conforming to IS:1732-1971 (rounds) and IS:1731-1971 (flats).

2. Dimensional Specifications

• Width of back sheet = Width of cabinet (extends top to bottom).
• Steel flats and rounds dimensions per IS:1731 & IS:1732.

3. Material Standards Referenced

• Structural steel: Ordinary quality (Second revision).
• Cold rolled carbon steel sheets (Second revision).
• Hot rolled carbon steel sheets and strips (Third revision).
• Slotted countersunk head screws (Third revision).

4. Testing

• Stripping Test: Mild steel plate 150×50 mm × 0.315 mm thickness per IS:101-1964, scratch must be free from jagged edges.

SI Units Relevant to Material Properties

Summary Diagram: Material Specification Flow

graph TD
  A[Steel Material] --> B[Grade: Fe 310-0 (St 32-0)]
  A --> C[Thickness ≥ 1.0 mm]
  A --> D[Surface: No burrs or dents]
  B --> E[Conforms to IS:1731 & IS:1732]
  F[Testing] --> G[Stripping Test per IS:101]
  G --> H[Scratch free from jagged edges]

Note: For detailed dimensional tables and mechanical properties, refer to IS:1731, IS:1732, and IS:197

IS 7761: Dimensions and Tolerances for Steel Bookcases

1. Key Dimensions (Clause 3.1)

2. Tolerances (Clause 3.2)

• Overall dimensions shall not vary by more than ± 5 mm.

3. Back Sheet Specification (Clause 4.3)

• Thickness: ≥ 1.0 mm steel sheet.
• Width: Matches cabinet width (840 mm).
• Quality: No burrs or dents; covers full height between top and bottom.

4. Screws (Clause 2.4)

• Must conform to IS 1365-1978 and IS 1366-1968 standards.

Summary Table:

flowchart LR
    A[Steel Bookcase Dimensions] --> B[Height: 1675 mm]
    A --> C[Width: 840 mm]
    A --> D[Depth: 305 mm]
    A --> E[Tolerance: ±5 mm]
    F[Back Sheet] --> G[Thickness ≥ 1.0 mm]
    F --> H[Width = 840 mm]
    F --> I[No burrs or dents]
    J[Screws] --> K[IS 1365-1978]
    J --> L[IS 1366-1968]

This ensures compliance with IS 7761 for steel bookcases regarding size, tolerances, and materials.

IS 7761 - Construction Details for Steel Bookcases

Key Specifications & Dimensions

• Back Sheet:

  • Thickness: ≥ 1.0 mm steel sheet (free from burrs/dents)
  • Width: Equal to cabinet width (840 mm)
  • Extends full height between top and bottom surfaces

• Overall Dimensions (Clause 3.1):

• Sheet Metal Components (Clause 6.1):
  • Remove all burrs, dents, sharp edges
  • Clean by pickling, scrubbing, rinsing to remove grease, rust, scale

Material Specifications Referenced

• Structural steel sheets: cold rolled or hot rolled carbon steel as per IS standards
• Fasteners: slotted countersunk head screws (IS specification)
• Welding: oxy-acetylene, metal arc, or resistance spot welding codes for mild steel

Summary Diagram of Steel Bookcase Dimensions

graph TD
  A[Top Surface] --> B[Back Sheet (1.0 mm thick)]
  B --> C[Bottom Surface]
  style B fill:#f9f,stroke:#333,stroke-width:2px
  D[Width = 840 mm]
  E[Height = 1675 mm]
  F[Depth = 305 mm]

This ensures structural integrity, dimensional accuracy, and quality surface finish as per IS 7761.

IS 7761 - Assembly Key Points

1. Sheet Metal Components (Clause 6.1)

• Use steel sheets ≥ 1.0 mm thick for backs.
• Back width = cabinet width (840 mm).
• Back extends full height (1675 mm) between top and bottom.
• Remove all burrs, dents, and sharp edges.
• Clean components by pickling, scrubbing, and rinsing to remove grease, rust, and scale.

2. Dimensions and Tolerances (Clause 3.1)

3. Material Specifications

• Ordinary quality structural steel sheets (cold/hot rolled).
• Steel bars and flats as per relevant IS specifications.
• Use slotted countersunk head screws for assembly.
• Welding and joining per IS codes for oxy-acetylene, metal arc, and resistance spot welding.

Assembly Workflow (Simplified)

flowchart TD
    A[Cut Steel Sheets] --> B[Remove Burrs & Dents]
    B --> C[Pickling & Cleaning]
    C --> D[Form Components]
    D --> E[Assemble using Screws/Welding]
    E --> F[Final Inspection & Finishing]

This ensures structural integrity and compliance with IS 7761.

IS 7761: Surface Treatment & Finishing - Key Points

1. Phosphating Treatment

• After pickling, mild steel parts must receive phosphating treatment per Class C of IS:3618-1966.
• Application process follows IS:6005-1970.
• Purpose: corrosion protection via phosphate coating.

2. Paint & Primer Specifications

• Putty: Must comply with IS:110-1968 for filling surfaces.
• Aluminium primer: As per IS:5660-1970.
• Paint types include:
  • Ready mixed paint (brushing, grey filler) for enamels.
  • Aluminium red oxide primer.
  • Spraying, finishing, stoving enamel.
  • Exterior enamel undercoating and finishing.

3. Stripping Test (Clause 7.4)

• Sample size: 150×50 mm, thickness 0.315 mm.
• Test per IS:101-1964 (Clause 17).
• Scratch after test must be free from jagged edges.

Summary Table: Key Standards for Surface Treatment

flowchart LR
    A[Pickling] --> B[Phosphating Treatment (IS:3618)]
    B --> C[Putty Application (IS:110)]
    C --> D[Primer Coating (IS:5660)]
    D --> E[Painting & Finishing]
    E --> F[Stripping Test (IS:101)]

This ensures corrosion resistance, surface finish quality, and durability of mild steel components per IS 7761.

IS 7761: Performance Requirements of Finish - Key Points

1. Finish Requirements (Clause 6.2):

• All components must have a color finish mutually agreed by purchaser and manufacturer.

2. Stripping Test (Clause 7.4):

• Sample size: 150 mm × 50 mm, thickness 0.315 mm.
• Test as per IS 101-1964, Clause 17.
• Scratch after test must be free from jagged edges.

3. Paint & Treatment Specifications:

• Phosphate treatment for corrosion protection (IS standards referenced).
• Various paint types specified:
  • Ready mixed paint (brushing, grey filler)
  • Aluminium red oxide primer
  • Spraying, finishing stoving enamel
  • Exterior enamel (undercoating & finishing)
• Enamel paint coats per IS 151-1950, IS 2932-1974, or IS 2933-1975.

4. Order Information (Clause 8.1):

• Purchaser must specify:
  • Colour of finish
  • Alternative construction/finish methods if any.

Summary Table: Stripping Test Sample

flowchart LR
    A[Component] --> B[Surface Preparation]
    B --> C[Phosphate Treatment]
    C --> D[Primer Coating]
    D --> E[Enamel Paint Coats]
    E --> F[Stripping Test (IS 101:1964)]
    F --> G{Scratch Jagged?}
    G -- No --> H[Pass]
    G -- Yes --> I[Fail]

For detailed painting procedures, refer to relevant IS codes for enamel and primers mentioned above.

IS 7761 - Technical Information to be Supplied by Purchaser (Clause 8)

When placing orders, the purchaser must provide the following key technical details:

• Colour of finish: Specify the exact colour required for the product finish.
• Alternative methods: If multiple construction or finishing methods are acceptable, clearly state the preferred option(s).

Additional Relevant Specifications

• Back Panel (Clause 4.3):

  • Material: Steel sheet, minimum 1.0 mm thickness
  • Quality: Free from burrs and dents
  • Size: Width equal to cabinet width; extends fully between top and bottom surfaces

• Corrosion Protection Test (Clause 7.5):

  • Test panel size: 150 mm × 100 mm, thickness 1.25 mm
  • Test standard: IS 101:1964 (Condensation corrosion test)
  • Requirement: No corrosion after test

Summary Table for Purchaser's Information

This ensures clarity and quality compliance in the supply process.

flowchart TD
    A[Purchaser places order] --> B{Provide Technical Info?}
    B -- Yes --> C[Specify Colour of Finish]
    B -- Yes --> D[Specify Construction/Finish Method]
    C & D --> E[Supplier processes order]
    B -- No --> F[Order incomplete, delay possible]

Packaging Specifications from IS 7761 (Steel Book Cases)

Key Dimensions (Clause 3.1):

Material Specification (Clause 4.3):

• Back sheet thickness: ≥ 1.0 mm steel sheet
• Back sheet width: equal to cabinet width (840 mm)
• Back sheet must be free from burrs and dents
• Back extends from top to bottom surfaces

Marking (Clause 10.1.1):

• Steel book cases may bear the ISI Certification Mark as per Indian Standards Institution rules.
• ISI mark ensures compliance with quality, inspection, and testing.

Packaging & Marking Summary

• Steel thickness and dimensions ensure structural integrity during packaging and transport.
• ISI Mark guarantees product quality and conformity.
• Packaging should protect against physical damage (dents/burrs) especially on back sheets.

flowchart TD
    A[Steel Book Case] --> B[Dimensions: 1675x840x305 mm]
    A --> C[Back Sheet: ≥1.0 mm Steel]
    C --> D[Free from Burrs & Dents]
    A --> E[ISI Certification Mark]
    E --> F[Quality Assurance]

For detailed packaging methods, refer to ISI licensing and inspection protocols.

IS 7761 - Marking of Steel Book Cases (Clause 10.1 & 10.1.1)

Key Specifications:

• Manufacturer Identification:

  • All steel book cases must be marked with the manufacturer's name and identification number.
  • The identification number on the key must be unique and not the same as key step numbers.
  • The lock must bear the same identification number as its corresponding keys.

• ISI Certification Mark:

  • Steel book cases may bear the ISI mark indicating compliance with IS standards, subject to licensing by the Indian Standards Institution.

Summary Table for Marking Requirements

Notes on ISI Mark Usage

• ISI mark ensures product quality under ISI supervision.
• Licensing and conditions governed by Indian Standards Institution.

Related Standards & Tests

• Stripping Test: IS 101-1964 for surface finish.
• Surface Treatment: Phosphate treatment for corrosion protection.
• Paints & Enamels: Specifications for primers and finishing coats.

flowchart LR
    A[Steel Book Case] -->|Mark| B[Manufacturer's Name + ID]
    C[Key] -->|Mark| D[Maker's Name + Unique ID]
    E[Lock] -->|Mark| F[Same ID as Key]
    G[ISI Mark] -->|Optional| A

This ensures traceability, quality assurance, and compliance with IS standards for steel book cases.