Specification for preservative-treated plywood

IS 5539: Scope - Key Specifications & Tables

Scope Summary:

• IS 5539 covers plywood dimensions, tolerances, and mechanical properties.
• Amendments rename Appendices to Annexes and update clause/table references.

Key Formulas & Tables:

1. Dimensions & Tolerances (Clause 8.3)

Edge straightness and squareness tested as per Annex C.

2. Static Bending Strength (Clause 9)

Tested as per IS 1734 (Part 11):

• MOE = Modulus of Elasticity
• MOR = Modulus of Rupture

Notes:

• Testing method refers to IS 1734 (Part 11) for static bending.
• Clauses 8-11 renumbered as 10-13 in amendments.
• Annex A and Annex B replace previous Appendices.

flowchart LR
  A[Plywood Sample] --> B[Measure Dimensions]
  B --> C{Check Tolerances}
  C -->|Within Limits| D[Accept]
  C -->|Outside Limits| E[Reject]
  A --> F[Static Bending Test (IS 1734 Part 11)]
  F --> G[Calculate MOE & MOR]
  G --> H{Compare with Table 1 values}
  H -->|Meets Criteria| D
  H -->|Fails Criteria| E

This summary provides essential tolerance limits and mechanical property requirements

IS 5539: Types of Preservatives

3. TYPES OF PRESERVATIVES (Clause 3.1)

Key Notes:

• Net absorption of preservative must meet purchaser's specification (Clause 10.1).
• Net retention can be verified by weight difference before and after treatment or service tank readings (Clause 9.2.1).
• Refer IS: 401-1967 for detailed preservative descriptions.

Typical Net Retention Formula:

[ \text{Net Retention (kg/m}^3) = \frac{\text{Weight after treatment} - \text{Weight before treatment}}{\text{Volume of timber}} ]

flowchart LR
    A[Preservative Types] --> B[Type 1: Oil Type]
    A --> C[Type 2: Organic Solvent Type]
    A --> D[Type 3: Water Soluble Non-fixing]
    A --> E[Type 4: Water Soluble Fixed]

This classification aids in selecting preservatives based on timber use and environmental exposure.

IS 5539: Preparation of Plywood for Preservative Treatment

Key Specifications (Clauses 4.1, 5.2.1.1, 5.2.3.2)

• Moisture content: ≤ 16% before treatment.
• Surface condition: Clean, free from oil/dirt.
• Cutting/finishing: Should be done before treatment for uniform penetration (esp. method 5.2.3).

Treatment Process (Full-cell Pressure Impregnation)

Preservative Types (Clause 3.1)

Notes:

• Full-cell process ensures uniform preservative distribution; no post-treatment on cut/drilled surfaces needed (5.2.3.2).
• Concentration & pressure depend on species and thickness for required retention.

flowchart TD
    A[Plywood Preparation] --> B[Stacking (Vertical/Horizontal with spacers)]
    B --> C[Apply Vacuum ≥ 56 cm Hg (20-30 min)]
    C --> D[Introduce Preservative Without Breaking Vacuum]
    D --> E[Apply Pressure (2-12.5 kg/cm²)]
    E --> F[Maintain Pressure Until Absorption]
    F --> G[Break Pressure + Apply Vacuum (10-15 min)]
    G --> H[Remove Plywood - Treated Uniformly]

This summarizes IS

IS 5539 – Choice of Treatment (Clause 5.1)

• Governing factors (5.1.1):

  • Timber species in plywood
  • Sapwood content
  • Intended use of plywood after treatment

• Modes of Treatment (5.2):

  • Methods specified in 5.2.1 to 5.2.3 (e.g., pressure treatment, dipping, brushing)

• Preservative Treatment Recommendations (5.1.3):

  • Details on preservative type, absorption amount, and penetration depth are in Appendix A.

Key Specifications from Appendix A (Typical)

Summary:

• Choose treatment based on timber species & sapwood content.
• Use pressure treatment for deep preservative penetration.
• Follow Appendix A for absorption and penetration criteria.

flowchart TD
    A[Timber Species & Sapwood Content] --> B[Choice of Treatment]
    B --> C{Mode of Treatment}
    C --> D[Pressure Treatment]
    C --> E[Dipping]
    C --> F[Brushing]
    B --> G[Preservative Type & Dosage]
    G --> H[Absorption & Penetration per Appendix A]
    H --> I[Durable Treated Plywood]

For detailed values, always refer to Appendix A of IS 5539.

IS 5539 - Methods of Preservative Treatment: Key Points

Types of Preservatives (Clause 3.1)

Refer IS:401-1967 for detailed preservative descriptions.

Treatment Methods (Clause 5.2.2)

• Soaking or Surface Application after manufacture.
• Pressure treatment (Clause 5.2.1) or veneer treatment (5.2.3) recommended depending on service.

Recommended Preservative & Treatment for Various Service Conditions (Clause 10.1)

IS 5539: Conditioning After Treatment - Key Points

1. Conditioning Purpose

• Ensures uniform preservative dispersion in plywood thickness.
• No further treatment needed on cut/drilled surfaces after veneer treatment (Clause 5.2.3.2).

2. Moisture Content Consideration

• Moisture content of veneers before treatment affects soaking duration (Clause 4.1.3).

3. Treatment Methods (Clause 5.2.2)

• Soaking or surface application after manufacture.
• Pressure process or veneer treatment methods as per service condition.

4. Recommended Preservative Types & Minimum Retention (From Appendix A, Clause 10.1)

5. Notes on Conditioning

• Conditioning after treatment stabilizes moisture and preservative distribution.
• Ensures durability and service life per intended use.

Summary Diagram of Treatment & Conditioning Process

flowchart TD
    A[Veneer Preparation] --> B[Moisture Content Check]
    B --> C[Preservative Treatment]
    C --> D{Treatment Method}
    D -->|Pressure Process| E[Conditioning]
    D -->|Veneer Treatment| E
    D -->|Soaking/Surface Application| E
    E --> F[Uniform Preservative Dispersion]
    F --> G[Ready for Use - No Further Surface Treatment]

References: IS 5539 Clauses 4.1.3, 5

IS 5539 - Dimensions and Physical Requirements Summary

1. Standard Dimensions (Clause 8.1)

• Length × Width (mm):
  • 2400 × 1200
  • 2100 × 900
  • 2100 × 1200
  • 1800 × 900
  • 1800 × 1200

2. Thickness Options (Clause 8.2)

• Thickness (mm): 3, 4, 5, 6, 8, 9, 12, 15, 19, 22, 25
• Other dimensions allowed if agreed by manufacturer and purchaser.

3. Tolerances on Finished Boards (Clause 8.3)

Edge straightness and squareness tested as per Annex C.

4. Mechanical Properties - Static Bending Strength (Clause 9)

Test as per IS 1734 (Part 11): Static Bending Strength.

flowchart LR
    A[Dimensions] --> B[Length & Width]
    A --> C[Thickness]
    B --> D[Standard sizes]
    C --> E[Thickness options]
    F[Tolerances] --> G[Length & Width]
    F --> H[Thickness]
    F --> I[Edge straightness & Squareness]
    J[Mechanical Properties] --> K[MOE & MOR values]

This concise summary aids in specifying plywood dimensions, tolerances, and

IS 5539: Sampling and Testing Key Points

Sampling

• Samples are taken from a batch per IS 303:1960 guidelines (Clause 9.1).
• Finished plywood must be clean and free of stains except preservative color (Clause 8.1).

Dimensional Tolerances (Clause 8.3)

Edge straightness and squareness tested as per Annex C.

Static Bending Strength (Clause 9)

Test specimens per IS 1734 (Part 11):

• MOE = Modulus of Elasticity
• MOR = Modulus of Rupture

flowchart LR
    A[Batch of Plywood] --> B[Sampling as per IS 303]
    B --> C[Dimensional Checks]
    C -->|Length, Width, Thickness| D[Tolerance Limits]
    B --> E[Static Bending Test]
    E --> F[MOE and MOR values]
    F --> G[Conformance Check]

This summary aids quality control and compliance with IS 5539 for plywood.

IS 5539: Requirements for Absorption of Preservative

Key Points from IS 5539 & Related Codes:

• Extent of Penetration (Clause 9.2.2):

  • Test by taking random samples at least 15 cm from edges.
  • Use methods from Appendix C of IS 401-1967 (boring, cutting, chemical tests) to determine penetration depth.

• Net Absorption (Clause 10.1 & 9.2.1):

  • Absorption depends on purchaser's specifications and use conditions (see Appendix A).
  • Net retention can be checked by:
    • Service tank readings
    • Weight difference before and after treatment
  • Maintain an absorption log book and provide certification.

• Recommended Practice (Clause 5.1.3):

  • Choice of preservative, amount absorbed, and penetration depth are detailed in Appendix A (refer for specific values).

Typical Formula for Net Absorption:

[ \text{Net Absorption (kg/m}^3) = \frac{\text{Weight after treatment} - \text{Weight before treatment}}{\text{Volume of plywood}} ]

Summary Table (Indicative from Appendix A):

flowchart LR
    A[Start: Plywood Treatment] --> B[Measure Weight Before Treatment]
    B --> C[Treat with Preservative]
    C --> D[Measure Weight After Treatment]
    D --> E[Calculate Net Absorption]
    E --> F{Is Absorption as per Spec?}
    F -- Yes --> G[Maintain Log Book & Certify]
    F -- No --> H[Re-treat or Reject Batch]

Note: Always refer to the latest version of IS 5539 and IS 401 for detailed procedures and values.

IS 5539 - Marking of Plywood Sheets

Key Marking Requirements (Clause 11.1)

Each plywood sheet must be marked legibly and indelibly near the edge with:

• Manufacturer's name, initials, or trademark
• Year of manufacture
• IS number and treatment mark (see Appendix A)
• Type of plywood (conforming to IS: 303-1960, IS: 710-1957, IS: 1328-1958)

ISI Certification Mark (Clause 11.1.1)

• Use governed by Indian Standards Institution (Certification Marks) Act.
• Indicates compliance with quality, inspection, and testing standards.
• License required for use.

Appendix A: Treatment Mark & Preservative Specifications

IS 5539: Durability & Treatability of Timber Species for Plywood

Key References:

• Durability & treatability data per IS 401:1967 Appendix B.
• Timber species listed with:
  • Relevant Indian plywood standard/class (A, B, C, etc.)
  • Durability class (I, II, III)
  • Treatability class (a, b, c, d, e)

Durability Classification (Clause B-2.2)

Treatability Classification (Clause B-3.1)

• a, b, c, d, e indicate ease of preservative treatment (a = easiest, e = difficult).

Sample from Table 1 (Clause B-1.1)

Notes:

• A = IS 303 (General plywood)
• B = IS 710 (Marine plywood)
• C = IS 1328 (Decorative plywood)

flowchart TD
    A[Timber Species] --> B[Durability Class]
    B -->|≥120 months| C(Class I)
    B -->|60-119 months| D(Class II)
    B -->|≤59 months| E(Class III)
    A --> F[Treatability Class]
    F --> G[a-e scale: a = easiest, e = hardest]
    A --> H[Plywood Class (A,B,C...)]

IS 5539: Recommended Practices for Preservative Treatment of Plywood

Key Table: Service Conditions and Preservative Types (Excerpt)

Additional Notes:

• Preservative Types:
  • Type 1: Creosote or creosote-fuel oil mix
  • Type 2: Water-soluble preservatives (non-color imparting)
  • Type 4: Copper-Chrome-Arsenic or Acid Copper-Chrome compositions
• Treatment Modes:
  • Pressure Process: Forced impregnation under pressure (Clause 5.2.1)
  • Soaking: Immersion for absorption (Clause 5.2.2)
  • Veneer Treatment: Surface treatment of veneers (Clause 5.2.3)
• Retention Measurement: Net retention calculated by weight difference before and after treatment (Clause

IS 5539: Edge Straightness and Squareness Testing

Edge Straightness (Clause 1.1, 8.3, Annex C)

• Use a straight edge at least equal to full plywood length.
• If edge is convex, hold straight edge to give equal gaps at ends.
• Measure the maximum gap (mm) between edge and straight edge.
• Tolerance:
  • 2 mm per 1000 mm length (0.2%)

Squareness (Clause 8.3, Annex C)

• Measure squareness between edges using a square or equivalent.
• Tolerance:
  • 2 mm per 1000 mm (0.2%)

Dimensional Tolerances (Table 8.3)

Summary Table for Edge Straightness & Squareness

flowchart LR
    A[Plywood Edge] --> B[Straight Edge]
    B --> C[Measure Max Gap]
    A --> D[Check Squareness]
    D --> E[Measure Deviation]
    C & E --> F{Within Tolerance?}
    F -->|Yes| G[Pass]
    F -->|No| H[Fail]

Note: Testing must follow Annex C procedures for accuracy and repeatability.

IS 5539 - Static Bending Strength of Plywood

Key Specifications (Clause 9 & Table 1)

• Test Method: As per IS 1734 (Part 11) - Determination of static bending strength.
• MOE and MOR values are average and minimum individual values required for plywood samples.

Important Notes:

• MOE measures stiffness; MOR measures maximum bending stress before failure.
• Values differ along and across grain due to plywood anisotropy.
• Test specimens must be taken in both directions for compliance.

Formula for Bending Stress (MOR):

[ \sigma = \frac{3PL}{2bd^2} ]

Where:

• ( \sigma ) = bending stress (N/mm²)
• ( P ) = load at failure (N)
• ( L ) = span length (mm)
• ( b ) = width of specimen (mm)
• ( d ) = thickness of specimen (mm)

Summary:

• Ensure plywood meets minimum MOE and MOR values in both directions.
• Use IS 1734 (Part 11) for test procedure.
• Check tolerances and edge straightness per Clause 8.3 and Annex C.

flowchart LR
    A[Test Specimen] --> B[Load Application]
    B --> C{Measure Deflection}
    C --> D[Calculate MOE]
    C --> E[Calculate MOR]
    D --> F[Compare with IS 5539 Values]
    E --> F
    F --> G{Pass/Fail}

IS 5539 Amendment No. 4 (1969) primarily updates terminology and references related to Annexes and Appendices:

Key Changes:

• Appendix A renamed as Annex A
• Appendix B renamed as Annex B
• Table 1 renamed as Table 2
• Clause references updated to:
  • Clauses 5.1.3, 5.1.4, 12.1, 13.1(c) refer to Annex A
  • Clauses 5.1.4 and 5.2.1 refer to Annex B
• All mentions of "Appendix" replaced by "Annex" in clauses 5.1.3, 5.1.4, 10.1, and 11.1(c)
• Table references updated from Table I to Table 2 in Annex B clauses B-1.1 and B-3.1

Summary Table:

Practical Impact:

• Use Annex A and Annex B for all design data or supplementary info.
• Refer to Table 2 for tabulated data previously in Table 1 or Table I.
• Clause cross-references updated accordingly for clarity and consistency.

This amendment ensures uniform terminology and avoids confusion between appendices and annexes in IS 5539 documentation.