converted timber for lorry bodies

IS 2179 - Scope: Key Specifications & Tables

1. Scope Summary

IS 2179 covers specifications for timber used in vehicle bodies, including body sides, floors, front, and tailboards. It defines permitted timber species, dimensions, surface quality, and preservative treatments.

2. Permissible Timber Species (Clause 2.1, Table A-2)

*Subject to preservative treatment per Clause 8.1.

3. Dimensions (Clause 6.1)

• Dimensions of planks and scantlings are as ordered.
• Refer to detailed project specifications or client requirements.

4. Surface Cracks Allowance (Clause 7.3.8, Table 7.3.3.2)

*Cracks on any surface except ends are permissible within these limits.

5. Preservative Treatment

• Timber species marked with * require prophylactic treatment (Clause 8.1).
• Treatment ensures durability and resistance to decay.

Summary Diagram: Timber Selection & Quality Checks

flowchart TD
   

IS 2179: Species of Timber for Cross-Bearers and Longitudinal Runners

Key Table (Clause 1.1, Appendix A)

Specifications Summary:

• These species are recommended for cross-bearers and longitudinal runners in lorry body manufacturing.
• Timber should be converted to planks and scantlings as per IS 2179.
• Selection is based on strength, durability, and workability suitable for vehicle structural components.

Additional Notes:

• Use Teak (TEA) and Sissoo (SIS) for higher durability.
• Species like Aini (AIN) and Padri (PAD) are also commonly used.
• Ensure timber is seasoned and free from defects for structural integrity.

graph LR
A[Cross-Bearers & Longitudinal Runners] --> B[Aini (AIN)]
A --> C[Bijasal (BIJ)]
A --> D[Deodar (DEO)]
A --> E[Hathipaila (HAT)]

IS 2179: Species of Timber for Lorry Body Components

Key Timber Species for Body Sides, Floor, Front, and Tailboard (Appendix A)

Notes:

• These species are selected for their strength, durability, and suitability for different lorry body parts.
• Body sides, floor, front, and tailboard require timber with good load-bearing and wear resistance.
• Refer to Appendix A of IS 2179 for detailed specifications on timber quality, seasoning, and treatment.

Typical Use Summary

This ensures durability and safety in lorry body construction per IS 2179 standards.

IS 2179: General Requirements and Defects

1. Measurements (Clause 6.3)

• Length (m): Measured at midline; fractions rounded down to nearest 0.05 m.
• Width (cm or mm): Measured at narrowest point; rounded to nearest cm.
• Thickness (cm or mm): Measured at narrowest point; rounded to nearest cm.
• Volume (m³): Computed from accepted sizes, accurate to 3 decimal places.

2. Permissible Defects (Clause 7.3)

• Defects in 7.3.1 to 7.3.8 are permissible collectively, not individually.
• Surface cracks (Clause 7.3.8): Allowed on any surface except ends.

Summary:

• Measure dimensions carefully and round as specified.
• Surface cracks allowed within limits depending on thickness.
• Defects are considered in totality, not individually.

flowchart TD
    A[Measure Length] --> B[Round down to nearest 0.05 m]
    A --> C[Measure Width & Thickness]
    C --> D[Round to nearest cm]
    D --> E[Calculate Volume (m³)]
    E --> F[Check Defects]
    F --> G[Surface Cracks Allowed?]
    G -->|Yes| H[Check Crack Depth Limits]
    H --> I[Accept if ≤ Specified Depth]
    G -->|No| J[Reject]

This ensures quality control per IS 2179 standards.

IS 2179: Moisture Content for Timber

Key Specifications (Clauses 5.2 & 5.3)

• Tolerance: +3% moisture content allowed during rainy/humid seasons (e.g., Assam, Malabar).

Important Notes:

• Moisture content is critical for durability and strength.
• Values refer to timber at initial supply.
• Moisture content limits vary by climatic zones (see IS 287-1973 for zone-wise details).
• Moisture content is measured by weight loss on drying or moisture meters.

Moisture Content Calculation Formula:

[ \text{Moisture Content (%)} = \frac{W_{wet} - W_{dry}}{W_{dry}} \times 100 ]

• (W_{wet}) = weight of the sample before drying
• (W_{dry}) = weight after oven drying (usually at 103 ± 2°C until constant weight)

flowchart LR
    A[Timber Sample] --> B[Measure Wet Weight (W_wet)]
    B --> C[Oven Dry at 103°C]
    C --> D[Measure Dry Weight (W_dry)]
    D --> E[Calculate Moisture Content %]

This ensures timber meets IS 2179 moisture criteria for structural reliability.

IS 2179: Dimensions, Tolerances, and Measurements for Timber

Key Points:

• Moisture Content Tolerance (Clause 5.3):
  +3% permissible during rainy season or in humid areas (e.g., Assam, Malabar).

• Dimensions (Clause 6.1):
  Dimensions of planks and scantlings shall be as ordered.

• Tolerances on Unplaned Cut Sizes (Clause 6.2):

  • Width: Tolerance applies irrespective of piece width (exact tolerance values not provided in excerpt).

Timber Species for Body Sides, Floor, Front, Tailboard (Clause 2.1, Table A-2):

(Subject to prophylactic treatment as per Clause 8.1)

Units & Symbols (SI Units):

Summary Table: Moisture Content Tolerance

For exact dimensional tolerances on width/thickness, refer to full Clause 6.2 in IS 2179.

flowchart LR
    A[Timber Dimensions] --> B[Ordered Size]
    A --> C[Tolerances]
    C --> D[Width: ± as per Clause 6.2]
    C --> E[Thickness: ± as per Clause 6.2

IS 2179: Permissible Defects Summary

Key Points from Clause 7.3 (Permissible Defects)

• Defects are permissible collectively, not individually (Clause 7.2).
• Defects specified in Clauses 7.3.1 to 7.3.8 are allowed within limits.

Surface Cracks (Clause 7.3.8)

• Cracks are not allowed on ends, only on other surfaces.
• Measurement of thickness is at the narrowest point (Clause 6.3c).

Measurement Rules (Clause 6.3)

• Length: Measured at midline, rounded down to nearest 0.05 m.
• Width & Thickness: Measured at narrowest point, rounded to nearest cm.
• Volume: Computed in m³, accurate to three decimals.

Practical Notes:

• Always check combined defects for acceptance.
• Use these limits to assess timber quality before preservative treatment (Clause 8).

flowchart LR
  A[Measure Thickness] --> B{Thickness Range}
  B -->|<=5 cm| C[Max Crack Depth = 1.5 mm]
  B -->|>5 & <=10 cm| D[Max Crack Depth = 3 mm]
  B -->|>10 cm| E[Max Crack Depth = 6 mm]
  C & D & E --> F[Check cracks only on surfaces excluding ends]
  F --> G[Accept if within limits]

This ensures structural integrity and durability per IS 2179 standards.

IS 2179: Preservative Treatment Key Points

1. Prophylactic Treatment (Clause 8.1)

• All sapwood-containing timber and those marked * in Appendix A must be treated as per Group 7, Table 2 of IS 401-1967.
• Pressure treatment is mandatory for unlimited sapwood (Clause 7.3.6.1).

2. Surface Crack Limits (Clause 7.3.8)

3. End Coating Materials (Clause 9.1)

Anti-splitting-cum-preservative composition (parts by weight):

Summary Diagram: Treatment Process Flow

flowchart TD
    A[Timber with Sapwood] --> B{Marked with * in Appendix A?}
    B -- Yes --> C[Prophylactic Treatment (IS 401-196

IS 2179 - Marking and Identification of Timber

Key Specifications (Clause 10.1)

Each timber piece shall be legibly and indelibly marked on a broad face about 30 cm from the end with:

• a) Species Abbreviation: Use symbols from Appendix A (see table below).
• b) Size: Dimensions in which timber is accepted.
• c) Supplier Identification: Name, initials, or recognized trademark.
• d) Year of Supply

Species Abbreviated Symbols (Excerpt from Appendix A)

(Refer full Appendix A for complete list)

Optional Marking (Clause 10.1.1)

• ISI Certification Mark may be added, indicating compliance with ISI quality control and inspection.

Summary Diagram: Marking Location on Timber

graph LR
A[Timber Piece] --> B[Marking on Broad Face]
B --> C[Approx. 30 cm from End]
C --> D[Species Symbol, Size, Supplier, Year]

Note: Marking must be durable and clear for traceability and quality assurance as per IS 2179.

IS 2179: Testing and Compliance - Key Points

1. Timber Species for Vehicle Bodies (Clause 2.1, Table A-2)

• Permitted species include:
  • Amari (AMA) - Amoora spp.
  • Benteak (BEN) - Lagerstroemia lanceolata
  • Chickrassy (CHI) - Chukrasia velutina (subject to treatment as per 8.1)
  • Others like Gurjan (GUR), Sal (SAL), Piney (PIN), etc.

2. Moisture Content & Seasoning

• Timber must conform to moisture content limits as per zones (introduced in this revision).
• Seasoning provisions are mandatory to ensure durability and dimensional stability.

3. Testing & Compliance

• Final test values must be rounded off according to IS:2-1960.
• Compliance is based on observed or calculated values matching specified limits.

4. Units & Symbols (SI Units)

• Force: ( N = kg \cdot m/s^2 )
• Pressure: ( 1 Pa = 1 N/m^2 )

Summary Diagram: Compliance Workflow

flowchart TD
    A[Select Timber Species] --> B[Seasoning & Moisture Check]
    B --> C[Physical & Mechanical Testing]
    C --> D{Test Results}
    D -->|Within Limits| E[Compliance Confirmed]
    D -->|Outside Limits| F[Reject or Reprocess]

Note: Refer Clause 8.1 for specific prophylactic treatment requirements.

IS 2179 Annexures & Appendices: Key Timber Species & Units

Timber Species (Appendix A)

• Cross-bearers & Longitudinal Runners (A-1.1):

  • Examples: Teak (TEA), Sissoo (SIS), Deodar (DEO), Aini (AIN), Safed-siris (SSI).

• Body Sides, Floor, Front & Tailboard (A-2.1):

  • Examples: Amari (AMA), Benteak (BEN), Chickrassy (CHI), Sal (SAL), Kail (KAL).
  • Note: Some timbers require prophylactic treatment (Clause 8.1).

Units (SI Units)

• Force: ( N = 1,kg \cdot m/s^2 )
• Pressure: ( Pa = N/m^2 )

Summary Diagram of Timber Use

graph TD
  A[Cross-bearers & Longitudinal Runners] -->|Species| B(Teak, Sissoo, Deodar, etc.)
  C[Body Sides, Floor, Front & Tailboard] -->|Species| D(Amari, Sal, Chickrassy, etc.)
  E[Prophylactic Treatment] --> C

Use these tables and species lists for selecting timber as per IS 2179 Annexures.