Method of test for wood particle boards and boards from other lignocellulosic materials, Part 22: Determination of surface glue ability test

IS 2380 Part 22 - Scope Key Points

• Scope: This part deals with test methods for wood particle boards and boards from lignocellulosic materials, emphasizing surface strength determination.

• Surface Strength Formula:

  [ S_{ss} = \frac{63 \times T}{b^{4.8}} ]

  Where:

  • (S_{ss}) = Surface strength (kg/cm²)
  • (T) = Maximum torque (cm·kg)
  • (b) = Side dimension of square specimen (cm)

• Moisture Content: Determined as per IS 2380 (Part III)-1977 on a separate sample.

• Reporting: Individual and average strength values must be reported, rounding as per IS 2-1960.

Summary Table

flowchart TD
    A[Test Specimen] --> B[Measure Max Torque (T)]
    B --> C[Measure Side Dimension (b)]
    C --> D[Calculate Surface Strength \(S_{ss}\)]
    D --> E[Report Individual & Average Values]

Key Formula from IS 2380 Part 22 (Clause 5.1)

For determining surface strength (Sss) of wood particle boards or lignocellulosic materials:

[ \boxed{ S_{ss} = \frac{63 \times T}{b^{4.8}} } ]

• Sss = Surface strength (kg/cm²)
• T = Maximum torque recorded (cm·kg)
• b = Side dimension of square specimen (cm)

Reporting Requirements:

• Report individual and average strength values.

Additional Notes:

• This method is part of the test data and report requirements.
• Moisture content and density determination methods are referenced in IS 2380 Part III.
• The standard aligns with international practices and is specific to Indian conditions.

Summary Table

This formula is critical for evaluating the mechanical performance of wood particle boards under torsional stress.

IS 2380 Part 22: Test Specimen Preparation Key Points

• Specimen Size:

  • Square specimen: 50 mm × 50 mm
  • Thickness: same as finished board thickness
  • Cross-section measured with ±0.3% accuracy

• Loading Blocks:

  • Steel or aluminium alloy blocks, 50 mm square
  • Bonded to specimen faces using polyvinyl acetate dispersion-based adhesive (IS: 4835-1979)
  • Adhesive must ensure failure does not occur at glue line

• Bonding Procedure:

  1. Assemble blocks and specimen in jig
  2. Apply pressure (dependent on board density & adhesive) without damaging specimen
  3. Cure under ambient conditions for minimum 8 hours

• Moisture Content:

  • Determined as per IS 2380 (Part III)-1977 on separate but identical samples

• Surface Strength Calculation:
  [ S_{ss} = \frac{63 \times T}{b^2} ]
  Where:

  • ( S_{ss} ) = Surface strength (kg/cm²)
  • ( T ) = Maximum torque (cm·kg)
  • ( b ) = Side length of specimen (cm) = 5 cm

Specimen and Block Assembly (Fig. 1 Summary)

graph LR
A[Steel/Aluminium Block (50 mm square)] -- Bonded --> B[Test Specimen (50 mm square)]
B -- Bonded --> C[Steel/Aluminium Block (50 mm square)]

Summary:
Prepare 50×50 mm specimens with bonded steel/aluminium blocks, measure dimensions precisely, condition specimens, and calculate surface strength using the torque formula above.

IS 2380 Part 22: Test Apparatus & Experimental Arrangement Summary

1. Specimen & Loading Blocks (Clause 3.1)

• Specimen size: 50 mm × 50 mm square, thickness = board thickness.
• Loading blocks: Steel or aluminum alloy, 50 mm square, bonded to specimen faces.
• Bonding adhesive: Polyvinyl acetate dispersion-based (IS: 4835-1979).
• Bonding method: Assemble in jig, apply pressure (not damaging specimen), cure ≥ 8 hours ambient.

2. Experimental Setup (Clause 4.1)

• Bottom metal block fixed rigidly in vice.
• Top block held with slight vertical pressure to prevent rising during wrenching.
• Torque wrench applied slowly and steadily.
• Read maximum torque (T) in cm·kg at shear failure.

3. Moisture Content (Clause 4.1.1)

• Determine as per IS 2380 Part III (1977) on separate sample.

4. Surface Strength Calculation (Clause 5.1)

[ S_{ss} = \frac{63 \times T}{b^2} ]

5. Test Data Reporting

• Record individual and average surface strength values.

Diagram: Experimental Arrangement (Simplified)

graph TD
    A[Top Block] -->|Torque Wrench| B[Specimen + Loading Blocks]
    B --> C[Bottom Metal Block (Fixed)]
    style C fill:#f9f,stroke:#333,stroke-width:2px

Note: Ensure no failure at adhesive interface; measure specimen dimensions to ±0.3%.

IS 2380 Part 22: Test Procedure Key Points

Moisture Content (Clause 4.1.1)

• Determined as per IS 2380 (Part III)-1977 on a separate sample from the same material.

Experimental Setup (Clause 4.1)

• Bottom metal block fixed securely in a vice.
• Top block held with slight vertical pressure during torque application.
• Torque wrench turned slowly until shear failure.
• Maximum torque (T) recorded in cm·kg.

Surface Strength Calculation (Clause 5.1)

• Formula to calculate surface strength (Sss) in kg/cm²:

[ \boxed{ S_{ss} = \frac{63 \times T}{b^4.8} } ]

Where:

• (T) = Maximum torque in cm·kg
• (b) = Side dimension of square specimen in cm

Reporting

• Record individual and average surface strength values.
• Round off values per IS 2-1960.

Summary Table for Surface Strength Calculation

flowchart LR
    A[Prepare Specimen] --> B[Determine Moisture Content (IS 2380 Part III)]
    B --> C[Fix Bottom Block in Vice]
    C --> D[Apply Vertical Pressure on Top Block]
    D --> E[Turn Torque Wrench Slowly]
    E --> F[Record Maximum Torque (T)]
    F --> G[Calculate Surface Strength Sss = 63*T/b^4.8]
    G --> H[Report Individual & Average Strength]

This procedure ensures consistent and reliable surface glueability testing of wood particle boards.

IS 2380 Part 22: Calculation of Surface Strength

Key Formula (Clause 5.1)

Surface strength (Sss) is calculated from the maximum torque (T) applied on a square specimen of side length b:

[ \boxed{ S_{ss} = \frac{63 \times T}{b^4.8} } ]

• Sss = Surface strength (kg/cm²)
• T = Maximum torque (cm·kg)
• b = Side dimension of the square specimen (cm)

Testing & Reporting

• Record maximum torque during test.
• Calculate individual Sss values for each specimen.
• Report individual and average surface strength values.

Notes:

• The exponent 4.8 on b accounts for the non-linear relationship between specimen size and strength.
• This method applies to wood particle boards and lignocellulosic materials.

Summary Table

flowchart LR
    A[Apply Torque T on specimen] --> B[Measure Maximum Torque T]
    B --> C[Calculate Sss = 63 * T / b^4.8]
    C --> D[Report Individual & Average Surface Strength]

This concise formula and procedure ensure standardized surface strength evaluation per IS 2380 Part 22.

IS 2380 Part 22: Test Data and Reporting

Key Formula for Surface Strength (Clause 5.1)

[ S_{ss} = \frac{63 \times T}{b^{4.8}} ]

• Sss = Surface strength (kg/cm²)
• T = Maximum torque (cm·kg)
• b = Side dimension of square specimen (cm)

Moisture Content (Clause 4.1.1)

• Determined as per IS 2380 (Part III) - 1977 on a separate sample from the same material.

Reporting Requirements

• Record maximum torque (cm·kg).
• Calculate and report individual and average surface strength values.
• Round off results as per IS 2-1960.

Summary Table

flowchart TD
    A[Test Specimen] --> B[Measure Torque (T)]
    B --> C[Calculate Surface Strength Sss]
    C --> D[Report Individual & Average Values]

This ensures consistency and traceability in wood particle board testing per IS 2380 Part 22.

IS 2380 Part 22 — Precision and Accuracy: Key Formulas & Specifications

The code does not explicitly provide precision and accuracy clauses but includes:

Key Formula for Surface Strength (Clause 5.1)

[ S_{ss} = \frac{63 \times T}{b^4.8} ]

• ( S_{ss} ) = Surface strength in kg/cm²
• ( T ) = Maximum torque in cm·kg
• ( b ) = Side dimension of square specimen in cm

Reporting & Rounding (Clause 0.4)

• Final test values must be rounded as per IS 2-1960 (Rules for rounding off numerical values).

Moisture Content (Clause 4.1.1)

• Moisture content to be determined as per IS 2380 Part III (1977) on a separate sample.

Notes on Precision & Accuracy (General Engineering Practice)

• Precision relates to repeatability of test results; report individual and average values.
• Accuracy depends on calibration of equipment and adherence to test methods.
• Use calibrated torque meters and ensure specimen dimensions are measured accurately.

flowchart TD
    A[Test Specimen] --> B[Measure Side b]
    B --> C[Apply Torque T]
    C --> D[Record Max Torque]
    D --> E[Calculate Surface Strength Sss]
    E --> F[Report Individual & Average Values]
    F --> G[Round off as per IS 2-1960]

For detailed precision and accuracy criteria, refer to the relevant testing equipment standards and IS 2-1960 rounding rules.

IS 2380 Part 22 (1981) covers Safety and Handling of glass, but the code text lacks explicit clauses. Based on standard engineering practice and typical IS guidelines:

Key Safety and Handling Guidelines for Glass:

• Handling: Use padded gloves and safety goggles; avoid impact and sudden temperature changes.
• Storage: Store vertically, on padded racks, away from moisture and direct sunlight.
• Transportation: Secure with cushioning materials to prevent glass-to-glass contact.
• Safety Factor: For design, use a safety factor of 3 to 5 on glass tensile strength due to brittleness.
• Load Considerations: Account for wind, live loads, and thermal stresses per IS 875 and IS 456.

Typical Formula for Glass Stress:

[ \sigma = \frac{6 M}{b d^2} ] Where:

• (\sigma) = bending stress
• (M) = moment
• (b) = width of glass
• (d) = thickness of glass

Recommended Thickness (mm) for Safety Glass (Indicative):

flowchart LR
    A[Glass Manufacture] --> B[Packaging with Padding]
    B --> C[Vertical Storage]
    C --> D[Safe Transportation]
    D --> E[Careful Handling]
    E --> F[Installation & Use]

For detailed safety norms, refer also to IS 875 (Loads) and IS 456 (Concrete Structures) when glass is part of composite elements.

IS 2380 Part 22 - Key Notes and Recommendations

Key Formula for Surface Strength (Clause 5.1)

The surface strength (Sss) of wood particle boards is calculated from the maximum torque (T) recorded during testing:

[ \boxed{ S_{ss} = \frac{63 \times T}{b^4.8} } ]

• Sss = Surface strength (kg/cm²)
• T = Torque (cm·kg)
• b = Side dimension of the square specimen (cm)

Testing & Reporting

• Record maximum torque (T) in cm·kg.
• Calculate individual and average surface strength values.
• Moisture content must be determined as per IS 2380 Part III (1977) on separate samples.

Recommendations

• Follow consistent specimen preparation and moisture conditioning.
• Report all test data clearly with specimen dimensions and moisture content.
• Use the above formula strictly for square specimens.

Summary Table for Testing

flowchart TD
    A[Test Specimen] --> B[Measure Torque (T)]
    B --> C[Calculate Surface Strength Sss]
    C --> D[Report Individual & Average Values]
    A --> E[Determine Moisture Content (IS 2380 Part III)]
    E --> D

This ensures reliable and standardized surface strength evaluation of wood particle boards.