Commercial veneers -Specification

IS 14315 - Scope Key Points

• Scope: Specifies dimensions and tolerances for structural elements (e.g., precast concrete blocks).

• Tolerances (Clause 9.4.1, Table 9.4):

• Rounding Off: Final test or calculation results must be rounded per IS 2:1960 rules, retaining the same significant figures as specified.

• Definitions: Terminology follows IS 707:1976.

Summary Diagram of Tolerance Concept

graph LR
A[Specified Dimension] --> B[Measured Dimension]
B --> C{Within Tolerance?}
C -->|Yes| D[Accept]
C -->|No| E[Reject]

This ensures quality control by allowing only slight positive deviations in length and width, avoiding undersizing.

IS 14315 Key References and Specifications

• Tolerances on Dimensions (Clause 9.4.1, Table 9.4):

• Rounding Off (IS 2:1960):
  Final test or analysis values must be rounded off following IS 2:1960 rules, retaining the same number of significant figures as specified.

• Referenced Standards:

  • IS 2:1960 — Rules for rounding off numerical values
  • IS 707:1976 — Applicable for related specifications
  • Annex A of IS 14315 — Lists Indian Standards essential as adjuncts to this code.

This ensures dimensional accuracy and consistency in reporting test results per IS 14315.

IS 14315 - Key Definitions & Specifications

• Definitions: The standard uses specific terms as defined within its clauses for clarity in application (no explicit list provided in your context).

• Dimensional Tolerances (Clause 9.4.1):

• Rounding Off (IS 2:1960):
  Results must be rounded to the same number of significant digits as specified in the standard.

• Permissible Defects:
  Table 2 outlines acceptable defect categories (refer to Clauses 4, 6, 7 for details).

Summary:

• Use +6 mm / 0 mm for length tolerance, +3 mm / 0 mm for width.
• Round results per IS 2:1960 rules.
• Refer to Table 2 for defect limits.

flowchart TD
  A[Measured Dimension] --> B{Check Tolerance}
  B -->|Length| C[+6 mm / 0 mm]
  B -->|Width| D[+3 mm / 0 mm]
  C & D --> E{Is dimension within tolerance?}
  E -->|Yes| F[Accept]
  E -->|No| G[Reject or Rework]

For detailed defect categories and definitions, consult Clauses 4, 6, 7 and Table 2 of IS 14315.

IS 14315: Classification by Appearance for Veneers

Types of Surfaces & Defects Allowed (per m²)

Table 1: Quality Requirements of Veneers

Notes:

• Surface A is for premium quality with stricter limits.
• Surface B allows more defects but still maintains appearance.
• Defects must be scattered and not clustered.

This classification helps in selecting veneer quality based on intended use and visual requirements.

IS 14315: Quality Requirements for Veneers

Key Quality Specifications (Table 1)

Tolerances on Dimensions (Clause 9.4.1, Table 9.4)

Notes:

• All values are per square meter (m²) unless otherwise specified.
• Rounding off of values follows IS 2:1960 rules.
• Joints in surface A veneers must maintain minimum piece width for structural integrity and appearance.

flowchart LR
    A[Quality Requirements] --> B[Surface A: Stricter Limits]
    A --> C[Surface B: Relaxed Limits]
    B --> D[Defects: Discolouration, Dote, In

IS 14315: Preservation Treatment of Veneers - Key Points

Preservation Treatment (Clause 1.25)

• Soaking Solution & Conditions:
  • Soak veneers from non-durable species and sapwood in:
    • 1.25% boric acid or 1.9% borax solution
    • Temperature: 85℃ to 90℃
    • Duration: 10 to 40 minutes (depends on veneer thickness)
  • Alternatively:
    • Dip veneers in 2% boric acid or 3% borax solution for 2 minutes
    • Then block stack for at least 2 hours before drying

Veneer Quality (Tables 1 & 2)

• Face veneer: Type A or B
• Core and crossband veneer: Type B only
• Key defect limits for Type A & B surfaces (Table 1 excerpt):

Additional Notes

• Joints in veneers should be edge-spliced or taped (removable tape).
• Metal clips/staples must be removed.
• Perforated tapes allowed on glue side.

Summary Diagram: Preservation Treatment Process

flowchart TD
    A[Veneer Type: Non-durable or Sapwood] --> B{Choose Treatment}
    B -->|Soak| C[1.25% Boric Acid or 1.9% Borax]
    B -->|Dip| D[2% Boric Acid or 3% Borax]
    C --> E[Temperature 85

IS 14315: Core and Crossband Veneer Requirements

Key Specifications:

• Core and Crossband Veneers: Must be Type B as per Tables 1 & 2 (quality & grading criteria).
• Treatment for Non-Durable Species/Sapwood:
  • Soak in 1.25% boric acid or 1.9% borax solution at 85–90°C for 10–40 min (depending on thickness),
    OR
  • Dip in 2% boric acid or 3% borax for 2 min, then block stack for 2 hours before drying.

Veneer Dimensions & Tolerances:

• Add 50 mm trimming allowance to dimensions specified for general plywood in IS 12049:1987.

Joints in Veneers:

• Edge-spliced (jointed) to form Type A/B surfaces.
• Alternatively, use tape on face (remove later) or perforated tape on glue side.
• Metal clips/staples must be removed after jointing.

Table 1 & 2 (Summary for Type B Veneers)

Veneer Treatment Flow (Simplified):

flowchart TD
    A[Non-Durable or Sapwood Veneer] --> B{Treatment Method}
    B -->|Soak| C[1.25% Boric Acid or 1.9% Borax at 85-90°C for 10-40 min]
    B -->|Dip| D[2% Boric Acid or 3% Borax for 2 min]
    D --> E[Block stack for 2 hours]
    C --> F[Drying]
    E --> F

Summary: Core and crossband veneers must be Type B quality, treated against decay, dimensioned with 50 mm trimming allowance, and properly jointed per IS 14315 and IS 12049.

Joints in Veneers (IS 14315: Clause 8 & related clauses)

• Jointing Method: Veneers for Type A or B surfaces must be edge jointed (spliced).
• Alternative: Face taping is allowed but tape must be removed later.
• Metal clips/staples: If used, must be removed.
• Perforated tapes: Allowed on glue side.

Key Specifications from Table 1 (Quality Requirements)

Veneer Treatment (Clause 1.25)

• Soak in 1.25% boric acid or 1.9% borax at 85-90°C for 10-40 mins (thickness-dependent).
• Or dip in 2% boric acid or 3% borax for 2 mins, then block stack 2 hrs before drying.

Diagram: Jointing Concept

flowchart LR
    A[Veneer Sheets] --> B[Edge Jointing (Splicing)]
    A --> C[Face Taping (Temporary)]
    B --> D[Final Veneer Surface Type A/B]
    C --> D
    D --> E[Removal of Tape/Clips]

This ensures structural integrity and appearance quality for plywood veneers per IS 14315.

IS 14315: Dimensions and Tolerances Summary

• Dimensions of Veneers (Clause 9.2):
  Veneer dimensions = Dimensions for general purpose plywood (IS 12049:1987) + 50 mm (for trimming).

• Permissible Tolerances on Dimensions (Clause 9.4.1):

• Squareness Tolerance (Clause 9.4.2):
  Maximum squareness deviation = 0.2% of the dimension.

• Rounding Off (General):
  Follow IS 2:1960 for rounding numerical values, keeping the same number of significant digits as specified.

Quick Reference Formula for Squareness Tolerance:

[ \text{Max Squareness Deviation} = 0.002 \times \text{Dimension} ]

flowchart TD
    A[Veneer Dimension] --> B[Base Dimension from IS 12049]
    B --> C[Add 50 mm for trimming]
    C --> D[Apply Tolerances]
    D --> E{Check Squareness}
    E -->|Within 0.2%| F[Accept]
    E -->|Exceeds 0.2%| G[Reject]

This ensures veneers conform dimensionally and geometrically as per IS 14315.

IS 14315: Sampling and Conformity - Key Points

1. Sampling Method

   • Follow IS 7638:1986 for sampling general purpose plywood (IS 303:1989).
   • Representative samples must be drawn as per the prescribed method to ensure uniformity.

2. Conformity Criteria

   • Test results must be rounded off according to IS 2:1960 rules.
   • The number of significant digits retained should match the specified value's precision.

3. Edge Straightness Tolerance

   • Maximum allowable edge straightness deviation = 0.2% of the edge length.

4. Defect Limits (Table 1: Quality Requirements of Veneers)

Summary Diagram: Sampling & Conformity Flow

flowchart TD
    A[Draw Samples as per IS 7638] --> B[Test Samples]
    B --> C{Check Edge Straightness ≤ 0.2%}
    C -->|Pass| D[Check Defects per Table 1]
    C -->|Fail| E[Reject Batch]
    D -->|Within Limits| F

IS 14315: Marking and Certification — Key Points

1. BIS Certification Marking (Clause 11.3 & 11.3.1)

• Products may be marked with the BIS Standard Mark.
• Use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986.
• Licence conditions for using the Standard Mark can be obtained from BIS.

2. Rounding Off Results (General Clause)

• Final test/analysis results shall be rounded off as per IS 2:1960.
• Retain the same number of significant places as specified in the standard.

3. Dimensional Tolerances (Clause 9.4.1)

4. Additional References (Annex A)

• Related IS standards for plywood, timber preservation, and wood-based panels are referenced for comprehensive compliance.

Summary Diagram: Certification Process Flow

flowchart TD
    A[Manufacturer Produces Product] --> B[Apply for BIS Licence]
    B --> C{Licence Granted?}
    C -- Yes --> D[Mark Product with BIS Standard Mark]
    C -- No --> E[No Marking Allowed]
    D --> F[Product Certified as per IS 14315]

For detailed licensing conditions, consult the Bureau of Indian Standards directly.

IS 14315: List of Referred Indian Standards (Annex A)

Key Notes:

• For rounding off numerical values, IS 2:1960 rules apply.
• IS 707:1976 defines timber-related terminology used in IS 14315.
• Certification marking follows Clause 11.3.1 under BIS Act, 1986.
• Evaluation of lathe checks (Annex B) uses alcohol-soluble dye for depth measurement as % of veneer thickness.

Practical Use:

• Refer to these IS codes for detailed specifications, sampling, preservation, terminology, and dimensional tolerances related to plywood and wood-based panels.
• Use IS 707 for consistent terminology.
• Use IS 303 and IS 401 for plywood specs and timber preservation methods respectively.

flowchart LR
    A[IS 14315] --> B[IS 303: Plywood Specs]
    A --> C[IS 401: Timber Preservation]
    A --> D[IS 707: Timber Glossary]
    A --> E[IS 7638: Sampling Methods]
    A --> F[IS 12049: Dimensions & Tolerances]

This helps ensure compliance and uniformity in plywood and panel products per Indian standards.

IS 14315: Method of Evaluation of Lathe Checks

While IS 14315 does not explicitly provide formulas for lathe check evaluation, the key points related to dimensional tolerances and quality checks are:

Key Specifications:

• Squareness tolerance: 0.2% (Clause 9.4.2)
• Edge straightness tolerance: 0.2% (Clause 9.4.3)
• Dimensional tolerances (Clause 9.4.1):

Method of Evaluation:

• Draw representative samples as per IS 7638:1986 (General purpose plywood sampling).
• Use IS 2:1960 rounding rules for final test values.
• Lathe checks are typically evaluated visually or by measuring depth and frequency on the veneer surface.

Practical Notes:

• Measure lathe check depth and spacing using a microscope or magnifier.
• Compare with allowable limits (usually specified by veneer quality standards).
• Ensure dimensional tolerances and squareness are within limits to confirm veneer quality.

flowchart LR
    A[Sample Selection] --> B[Visual Inspection of Lathe Checks]
    B --> C[Measure Depth & Spacing]
    C --> D{Within Tolerance?}
    D -->|Yes| E[Accept Sample]
    D -->|No| F[Reject Sample]

For detailed lathe check depth limits, refer to veneer manufacturing standards or IS 303 (Plywood).

IS 14315: Committee Composition Summary

Committee: Wood Products Sectional Committee, CED 20
Location: Annex C of IS 14315

Key Details:

• Chairman:
  Dr. P. M. Ganapathy (Indian Plywood Industries Research and Training Institute, Bangalore)

• Members:
  Representatives from various sectors including:

  • Indian Plywood Industries Research and Training Institute
  • Public Works Department (UP)
  • Forest Departments (Assam, others)
  • Ministry of Defence
  • Plywood Manufacturers Associations (West Bengal, Assam, South India)
  • Directorate General of Technical Development
  • Indian Institute of Packaging
  • Central Public Works Department
  • National Test House
  • Indian Academy of Wood Science
  • Federation of Indian Plywood and Panel Industry
  • Central Building Research Institute (CSIR)
  • Directorate General of Civil Aviation

• Ex-officio Member:
  Shri Vinod Kumar, Director General, BIS

Notes:

• The committee includes technical experts, industry representatives, government officials, and research institute members ensuring comprehensive standard formulation.
• No direct formulas or tables for committee composition; composition is strictly representative and multidisciplinary.

graph TD
    A[Chairman: Dr. P. M. Ganapathy] --> B[Industry Experts]
    A --> C[Government Officials]
    A --> D[Research Institutes]
    B --> E[Plywood Manufacturers]
    B --> F[Packaging Institute]
    C --> G[Public Works Dept.]
    C --> H[Ministry of Defence]
    D --> I[CSIR]
    D --> J[Forest Research Institute]

For detailed member list and affiliations, refer Annex C of IS 14315.