Tower Bolts - Specification Part-2 Non-Ferrous Metals

IS 204 Part 2: Scope - Key Specifications & Tables

• Scope: Covers dimensions, minimum requirements, and conformity criteria for tower bolts used in skeleton towers.

1. Sampling & Conformity (Clause 9.2, Table 4)

2. Barrel Tower Bolts Dimensions (Clause 5.2.1, Table 1)

IS 204 Part 2: Referenced Standards Summary

• Clause 2.1 lists essential Indian Standards (IS) referenced for materials in IS 204 Part 2.
• These standards specify material types, grades, and properties necessary for design and manufacturing.

Key Referenced IS Standards Table (Excerpt)

Notes:

• These referenced IS codes provide detailed specifications for materials used in structural components.
• Always use the latest revision of these IS codes for compliance.
• Dimensions and minimum requirements in IS 204 Part 2 are binding where specified.

Usage Tip:

When designing or specifying materials, refer to the above IS codes for:

• Chemical composition
• Mechanical properties
• Dimensional tolerances
• Surface treatments and finishes

flowchart TD
    A[IS 204 Part 2] --> B[Material Specifications]
    B --> C{Referenced IS Codes}
    C --> D[IS 292: Brass Ingots]
    C --> E[IS 319: Brass Bars & Rods]
    C --> F[IS 410: Brass Sheets]
    C --> G[IS 733: Aluminium Bars]
    C --> H[IS 742: Zinc Alloy Castings]
    C --> I[IS 1285: Aluminium Sections]
    C --> J[IS 1868: Anodic Coatings]
    C --> K[IS 6760: Wood Screws]

This ensures harmonized design and quality control per BIS standards.

IS 204 Part 2: Types and Specifications of Tower Bolts

Types of Tower Bolts (Clause 3.1)

• Barrel Tower Bolts:

  1. Brass barrel with cast brass barrel & rolled/cast brass bolt
  2. Brass barrel with extruded brass sections & rolled/drawn brass bolt
  3. Brass barrel with brass sheet & rolled/drawn brass bolt
  4. Aluminium barrel with extruded aluminium alloy sections
  5. Zinc barrel with die-cast zinc alloy

• Skeleton Tower Bolts: 6. Brass skeleton with cast brass plate & staples, rolled/drawn brass bolt 7. Brass skeleton with extruded brass plate & staples, rolled/drawn brass bolt 8. Aluminium skeleton with extruded aluminium alloy plate, staples & bolt 9. Zinc skeleton with die-cast zinc alloy plate, staples & bolts

Key Specifications (Clause 1.2)

• Sheet thickness ≥ 1.2 mm must have countersunk screw holes (per IS 6760:1972).
• Smooth finish, free from defects.
• Removal of sharp edges.

Dimensions for Skeleton Tower Bolts (Clause 5.2.2, Table 2)

Material Requirements for Tower Bolts as per IS 204 Part 2

• Material Compliance: Manufacturer must provide a certificate of compliance to the relevant Indian Standard (Clause 9.5).

• Materials & Suitable Grades (Table 3, Clause 4.1):

• Note: The shapes in illustrative figures are not binding, but dimensions and minimum requirements are mandatory.

This ensures material quality and standardization for tower bolts used in construction.

IS 204 Part 2: Construction and Design Details Summary

1. Skeleton Tower Bolts Dimensions (Table 5.2.2)

• Tolerances: ±1 mm (length), ±0.5 mm (plate dimensions), +0.25/-0 mm (thickness), etc.

2. Material Specifications (Clause 4.1, Table 9.3)

3. Key Notes

• Dimensions in figures are illustrative; minimum specified dimensions are binding.
• Use specified material grades for durability and compliance.
• Bolt and plate dimensions vary with bolt diameter (D = 10 or 12 mm).

Visual Concept: Skeleton Tower Bolt

IS 204 Part 2 (1992) — Dimensions and Tolerances for Tower Bolts

Key Clauses:

• Clause 6.1: Dimensions & tolerances for Barrel Tower Bolts as per Table 1
• Clause 6.2: Dimensions & tolerances for Skeleton Tower Bolts as per Table 2
• Note: Illustrative shapes; dimensions and minimum requirements are mandatory.

Table 1: Barrel Tower Bolts (Selected Dimensions in mm)

Tolerances:

• Length of Barrel: -1 mm / +3 mm
• Width of Barrel: ±1 mm
• Diameter of Bolt: ±0.3 mm
• Length of Socket: ±0.25 mm
• Thickness of Metal: ±0.15 mm

Notes:

• Thickness varies by material: Brass, Aluminium, Zinc Alloy
• Number of holes for wooden screws is minimum and equally spaced.
• Dimensions apply to types 1 to 5 barrel tower bolts.

Summary Diagram (Conceptual)

graph LR
A[Barrel Tower Bolt] --> B(Length of Barrel B)
A --> C(Width of Barrel C)
A -->

IS 204 Part 2: Finishing and Surface Treatment of Tower Bolts

1. Finishing Specifications (Clause 7.1)

• Barrel Tower Bolts:

  • Brass (Types 1-3): Polished or plated as per purchaser.
  • Aluminium Alloy (Type 4): Anodized (Grade AC 10 per IS 1868:1982), transparent or dyed.
  • Zinc Alloy (Type 5): Oxidized, bronzed, or plated as per purchaser.

• Skeleton Tower Bolts:

  • Brass (Types 6-7): Bright finished.
  • Aluminium Alloy (Type 8): Anodized (Grade AC 10 per IS 1868:1982).
  • Zinc Alloy (Type 9): Oxidized, bronzed, or plated.

2. Material Grades (Clause 4.1, Table 3)

3. Key Dimensions (Excerpt from Table 1, Clause 5.2.1)

IS 204 Part 2: Packaging and Marking - Key Points

1. Packaging:

• The code does not specify detailed packaging dimensions or methods.
• Packaging must ensure protection against damage during transport and storage.
• Manufacturer should follow good industrial practice to maintain product integrity.

2. Marking Requirements (Clause 2.1 & Table 10):

• Marking must include:
  • Manufacturer's name or trademark.
  • IS standard number (IS 204 Part 2).
  • Grade or designation of the product.
  • Batch or heat number for traceability.
  • Any other relevant information as per the corresponding Indian Standard.

3. Certification (Clause 9.5):

• Manufacturer must provide a Certificate of Compliance confirming conformity to the relevant IS standards.

Summary Table: Marking Details

Note:

• The shapes in figures are illustrative; dimensions and minimum requirements are binding.
• Refer to related IS standards (e.g., IS 292, IS 319, IS 410) for material-specific marking and packaging details.

flowchart TD
    A[Manufacturing] --> B[Packaging]
    B --> C[Marking]
    C --> D[Certificate of Compliance]
    D --> E[Dispatch & Storage]

This ensures product quality, traceability, and compliance with IS 204 Part 2.

IS 204 Part 2: Sampling, Testing & Criteria for Conformity

1. Sampling Plan (Table 4 - Clause 9.2 & 9.4)

• Lot: Batch of bolts produced.
• Sample Size: Number of bolts randomly selected for testing.
• Permissible Defective: Maximum allowable defective bolts for the lot to conform.

2. Criteria for Conformity (Clause 9.4)

• A lot conforms if defective bolts ≤ permissible number.
• Otherwise, the lot is non-conforming.

3. Manufacturer's Responsibility (Clause 9.5)

• Must provide a Certificate of Compliance confirming conformity to relevant IS standards.

4. Packaging & Marking (Clause 8.2)

• Non-ferrous bolts must be suitably packed.
• Aluminium alloy bolts individually wrapped in tissue paper or polythene.
• Each packet/carton labeled with:
  • Manufacturer name/trade mark
  • Type
  • Size
  • Quantity

flowchart TD
    A[Lot of Tower Bolts] --> B[Sampling as per Table 4]
    B --> C{Number of Defective Bolts}
    C -->|≤ Permissible| D[Lot Conforms]
    C -->|> Permissible| E[Lot Does Not Conform]
    D --> F[Certificate of Compliance Issued]
    E --> G[Reject or Reprocess Lot]

This ensures quality control and compliance with IS 204 Part 2 requirements.

IS 204 Part 2: Marking - Key Points & Tables

Marking Specifications:

• Clause 10.1.1: Tower bolts may be marked with the BIS Standard Mark to indicate conformity.
• Marking ensures traceability and quality assurance.

Sampling & Conformity Criteria (Clause 9.2)

• This table guides quality control sampling for tower bolts.

Referenced Standards (Clause 2.1)

• IS 292: Leaded brass ingots and castings
• IS 319: Free-cutting brass bars, rods, sections
• IS 410: Cold rolled brass sheet, strip, foil
• IS 733: Wrought aluminium and alloy bars, rods, sections
• IS 742: Zinc base alloy die castings
• IS 1285: Wrought aluminium and alloy extruded hollow sections
• IS 1868: Anodic coatings on aluminium alloys
• IS 6760: Slotted countersunk head wood screws

Summary:
Marking with the BIS Standard Mark is optional but recommended for tower bolts. Quality sampling follows the table above to ensure conformity. Refer to the listed IS standards for material specifications related to marking and manufacturing.

flowchart LR
    A[Manufacture Tower Bolt] --> B{Mark with BIS Standard Mark?}
    B -- Yes --> C[Marking Applied]
    B -- No --> D[No Marking]
    C & D --> E[Sampling per Table 4]
    E --> F{Defective Units ≤ Permissible?}
    F -- Yes --> G[Lot Accepted]
    F -- No --> H[Lot Rejected]

IS 204 Part 2 - List of Referenced Indian Standards

This part of IS 204 references essential Indian Standards for materials used in construction and engineering. These standards specify material grades, properties, and designations.

Key Referenced IS Standards (Clause 2.1, Table):

Notes:

• These standards cover materials commonly used in structural and mechanical applications.
• Material specifications include chemical composition, mechanical properties, and manufacturing processes.
• Refer to each IS for detailed material grades and test methods.

BIS Contact & Regional Offices:

• Manak Bhavan, New Delhi - Central Office
• Regional offices in Kolkata, Chandigarh, Chennai, Mumbai, and others.

Summary Diagram: Referenced Standards Linkage

graph LR
A[IS 204 Part 2] --> B[IS 292: Brass Ingots]
A --> C[IS 319: Brass Bars & Rods]
A --> D[IS 410: Brass Sheets]
A --> E[IS 733: Aluminium Bars & Rods]
A --> F[IS 742: Zinc Alloy Castings]
A --> G[IS 1285: Aluminium Tubes]
A --> H[IS 1868: Anodic Coatings]
A --> I[IS 6760: Wood Screws]

Use these referenced IS codes to ensure material compliance and quality in design and fabrication as per IS 204 Part 2 requirements.