What are the grades of timber specified for packing cases?

Two grades are specified: Grade I and Grade II (Clause 3).

What is the maximum allowed moisture content in the timber?

The moisture content shall not exceed 20 percent at the time of inspection (Clause 4.2).

Are knots allowed in timber for packing cases?

Yes, but their size is restricted based on the grade. For Grade I, the diameter must not exceed 1/3 of the face width; for Grade II, it's 1/2 the face width (Table 1).

Is decay or rot permitted?

No, the timber must be free from any kind of rot, decay, and insect attack, except for certain limited stains in Grade II timber (Clause 4.1 and Table 1).

IS 5247

: 2000

converted timber (coniferous): Part 2 Packing cases and crates

CurrentSpecializedSpecificationMaterials Science · Timber and Timber Stores

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This standard specifies the requirements for converted coniferous timber intended for manufacturing packing cases and crates. It categorizes the timber into two grades, Grade I and Grade II, and defines the acceptable limits for various natural defects like knots, splits, wane, and decay, as well as setting a maximum moisture content to ensure durability.

converted timber (coniferous): Part 2 Packing cases and crates

Quick Reference Values

Maximum permissible moisture content20 percent

Number of grades specified2 (Grade I and Grade II)

Grade I - Maximum permissible knot diameter1/3 of the width of the face

Grade II - Maximum permissible knot diameter1/2 of the width of the face

Grade I - Maximum permissible length of splitEqual to the width of the piece

Grade II - Maximum permissible length of splitOne and a half times the width of the piece

Practical Notes

This standard is critical for quality control when procuring timber for bulk packaging, ensuring the crates have adequate strength and durability for shipping goods.

Pay close attention to moisture content (Clause 4.2); timber with more than 20% moisture can be prone to fungal attack and dimensional instability during transport and storage.

The choice between Grade I and Grade II directly impacts the cost and performance of the packing case; select the grade based on the value, weight, and fragility of the items to be packed.