Specification for numerical

IS 10090: Scope Overview

IS 10090 specifies numerical quality control for materials or products, focusing on sampling and conformity criteria.

Key Table: Scale of Sampling and Criterion for Conformity (Clause 9.2)

Interpretation:

• Lot Size: Total quantity in a batch.
• Sample Size: Number of units tested from the lot.
• Permissible Defectives: Maximum allowed defective units for lot acceptance.

This table guides quality control sampling to ensure product conformity with minimal defects.

flowchart LR
    A[Lot Size] --> B[Determine Sample Size]
    B --> C[Inspect Sample Units]
    C --> D{Number of Defectives ≤ Permissible?}
    D -->|Yes| E[Accept Lot]
    D -->|No| F[Reject Lot]

IS 10090 - Materials for Numericals: Key Specifications

1. Material Grades (Table 1, Clause 2.1)

2. Notes on Specifications

• • IS 292-1961: Brass ingots and castings (revised)
• • IS 305-1961: Aluminium bronze ingots and castings (revised)
• $ IS 306-1968: Tin bronze ingots and castings (second revision)
• § IS 28-1975: Phosphor bronze ingots and castings (third revision)
• || IS 617-1975: Aluminium and aluminium alloy ingots and castings for general engineering (second revision)

Summary

• Use Grade 3 Brass for brass numericals.
• For bronze, select from Grade 3 or 4 depending on alloy type.
• Aluminium numericals should use Designation 5230 or 4600 alloys per IS 617.

This ensures durability, machinability, and compliance with IS 10090 standards for numericals manufacturing.

IS 10090: Design and Shape of Numericals

Key Points from IS 10090:

• Clause 3.1:

  • The design and shape of numericals are not standardized in the code.
  • They shall be mutually agreed upon between the manufacturer and purchaser.

• Clause 2.1 & Table 1:

  • Specifies material grades for numericals, important for design considerations:

Practical Design Notes:

• Since shape is customizable, ensure:
  • Adequate thickness for durability.
  • Clear visibility of numerals.
  • Compatibility with mounting surfaces.

Summary:

• No fixed formula or shape in IS 10090.
• Material specifications are provided to guide durability and manufacturing.
• Final design is a collaborative decision.

flowchart LR
    A[Manufacturer] --> C[Design Proposal]
    B[Purchaser] --> C
    C --> D[Agreed Design & Shape]
    D --> E[Manufacturing as per IS Material Specs]

For detailed mechanical design (e.g., thickness, strength), refer to general engineering design standards or manufacturer guidelines.

IS 10090 - Size and Dimensions for Numericals

• Clause 4.1 specifies the standard sizes for numericals as:
  25 mm, 50 mm, 75 mm, 100 mm, 150 mm, and 300 mm.

• Clause 3.1 states the design and shape must be agreed upon by manufacturer and purchaser, allowing flexibility beyond size.

Summary Table of Sizes

Notes:

• No fixed shape or font style is mandated; customization is allowed.
• Dimensions refer to height of numerals.
• Thickness and stroke width depend on visibility and application.

flowchart LR
    A[Manufacturer] -->|Agrees on| B[Design & Shape]
    B --> C[Standard Sizes: 25, 50, 75, 100, 150, 300 mm]
    C --> D[Application-specific selection]

In essence: Use the specified sizes as a baseline and finalize design details through mutual agreement.

IS 10090: Manufacture of Numericals – Key Material Specifications

1. Material Requirements (Clause 2.1 & Table 1)

*Notes on IS Standards:

• IS 292-1961: Brass ingots and castings
• IS 305-1961: Aluminium bronze ingots and castings
• IS 306-1968: Tin bronze ingots and castings
• IS 28-1975: Phosphor bronze ingots and castings
• IS 617-1975: Aluminium and aluminium alloy ingots and castings

2. Manufacture Guidelines

• Materials must strictly comply with the above IS grades to ensure durability and performance.
• Casting quality and alloy composition are critical for the numerical's longevity and precision.

If you need design formulas or shape specifications, IS 10090 refers to separate clauses or standards for those, which are not detailed here. For casting design, consider standard foundry practices and IS 3177 for casting tolerances.

flowchart TD
    A[Material Selection] --> B{Material Type}
    B -->|Brass| C[IS 292-1961 Grade 3]
    B -->|Cast Bronze| D[IS 305-1961 Grade 3]
    B -->|Cast Bronze| E[IS 306-1968 Grade 4]
    B -->|Cast Bronze| F[IS 28-1975 Grade 3]
    B -->|Cast Aluminium| G[IS 617-1975 Designation 5230/4600]

Summary: Use specified IS grades for brass, bronze, and aluminium alloys to manufacture numericals as per IS 10090 Clause 2.1 and Table 1.

IS 10090: Finish Specifications for Numericals

• Brass and Bronze Numericals:

  • Must be finished smooth.
  • Finish types allowed:
    • Bright finish
    • Satin finish
    • Or plated (e.g., nickel or chrome plating).
  • Must be protected against discoloration (e.g., lacquering).

• Aluminium Numericals:

  • Must be anodized.
  • Anodizing quality should be at least Grade AC 10 as per IS 1868:1968.
    • This ensures corrosion resistance and durability.

Summary Table:

Notes:

• Bright finish: Polished to a mirror-like surface.
• Satin finish: Matte, non-reflective surface.
• Anodizing Grade AC 10: Minimum anodic coating thickness and quality ensuring durability.

flowchart TD
    A[Numericals] --> B[Brass/Bronze]
    A --> C[Aluminium]
    B --> D[Finish: Bright/Satin/Plated]
    D --> E[Protection: Anti-discoloration]
    C --> F[Finish: Anodized]
    F --> G[Quality: Grade AC 10 (IS 1868)]

This ensures longevity, aesthetics, and compliance with IS 10090.

IS 10090 - Marking Specifications Summary

• Clause 7.1: Each numerical (e.g., numerical control components or parts) must be legibly and indelibly marked.
• Marking should include:
  • Name of the manufacturer or
  • Trade mark, if any.

Key Points:

• Marking ensures traceability and authenticity.
• Indelible marking methods include stamping, engraving, or durable printing.
• Legibility must be maintained throughout the product's lifecycle.

No specific formulas or tables are provided for marking in IS 10090.

flowchart LR
    A[Manufacturer] --> B[Marking Process]
    B --> C[Indelible Mark]
    C --> D[Name / Trade Mark]
    D --> E[Legible & Durable]

This ensures easy identification and compliance with IS 10090.

IS 10090 Packaging - Key Specifications

• Clause 8.1:
  Numericals must be individually wrapped in polythene or tissue paper to prevent damage.

• Packing:
  Wrapped numericals are packed in multiples inside cardboard boxes for protection and ease of handling.

• Clause 8.2 - Package Marking:
  Each package must clearly display:

  • Quantity of numericals inside.
  • Manufacturer's name or trademark.

• Clause 9.2.1 - Sampling for Quality Check:

  • Random sampling from at least 10% of packages, minimum 3 packages.
  • Equal number of numericals selected from each chosen package for conformity testing.

Summary Table: Packaging Requirements

flowchart LR
    A[Numericals] --> B[Individually wrapped (Polythene/Tissue)]
    B --> C[Grouped in multiples]
    C --> D[Packed in cardboard boxes]
    D --> E[Mark package with Quantity & Manufacturer]
    E --> F[Sampling: 10% packages, min 3, equal numericals]

This ensures protection, traceability, and quality control per IS 10090.

IS 10090: Scale of Sampling & Criteria for Conformity

Key Points from Clause 9.2 & 9.4:

• Sample Size depends on Lot Size as per Table 2.
• Permissible number of defectives defines acceptance criteria.
• A lot is conforming if defectives ≤ permissible number.

Table 2: Scale of Sampling and Criterion for Conformity

Summary:

• Select sample size based on lot size.
• Test samples for defects.
• Accept lot if defectives ≤ permissible number.
• Reject otherwise.

flowchart TD
    A[Determine Lot Size] --> B[Select Sample Size from Table 2]
    B --> C[Test Samples]
    C --> D{Defectives ≤ Permissible?}
    D -- Yes --> E[Lot Accepted]
    D -- No --> F[Lot Rejected]

This ensures quality control per IS 10090 for anodic coatings on aluminium.