Specification for double action floor springs (without oil check) heavy door

IS 7197: Scope - Key Specifications & Material Requirements

Scope: Covers materials and workmanship for floor springs used in door closing mechanisms.

Key Material Specifications (Clause 4.1, Table 1)

IS 7197 - Definitions & Material Specifications for Floor Springs

Key Definitions (Clause 2.0)

• Defines terms related to floor springs such as foundation main body, spring rod, governing pivot, top cover, spring, shoe, and top centre pivot & pin.

Material Specifications (Clause 4.1, Table 1)

IS 7197: Type and Shape - Key Specifications

Material Thickness & Grades (Clause 3 & 4.1)

IS 7197 - Clause 4.1: Materials for Floor Springs

IS 7197 - Performance Requirements: Key Specifications

1. Material Requirements (Clause 4.1, Table 1)

• Foundation main body: Brass sheet (≥1.25 mm, CuZn 40 IS:410), Mild steel sheet (≥1.25 mm IS:226), Cast iron Grade 20 (IS:210), Aluminium die-castings (≥2 mm IS:617), Zinc alloy die-castings (≥2 mm IS:742).
• Spring rod: Mild steel (IS:226).
• Governing pivot: Case-hardened mild steel or malleable cast iron Grade 1 (IS:2708, IS:2108).
• Top cover: Cast brass Grade 3 (IS:292), brass sheet (≥1.25 mm), aluminium die-castings (≥2 mm).
• Spring: Spring steel Grade 1 (IS:4454).
• Shoe: Cast brass Grade 3, mild steel, or cast iron Grade 20.
• Top centre pivot and pin: Cast brass and mild steel (IS:292, IS:226).

2. Performance Criteria (Clause 8)

• Door panel must move smoothly with circular motion.
• Horizontal & vertical adjustments must be possible.
• Door leaf should be removable without frame damage.

3. Sampling & Conformity (Appendix A)

• Manufacturer must provide compliance certificates per IS standards.
• Sampling scale and criteria ensure material and performance conformity.

Summary Table: Material Thickness & Grades

IS 7197: Dimensions and Tolerances for Floor Springs

Key Points from Clause 6.1

• Dimensions and tolerances of floor springs shall be mutually agreed between purchaser and manufacturer.
• No fixed dimensional tolerances are prescribed in the code; customization is allowed.

Material Thickness & Specifications (Clause 4.1 - Table 1)

Summary:

• Thickness generally ranges from 1.25 mm (brass, aluminium sheets) to 2 mm (die-castings).
• Material grades are per relevant IS codes for durability and performance.
• Tolerances are project-specific and must be agreed upon.

Visual Summary of Thicknesses

IS 7197 - Construction: Key Material Specifications for Floor Springs (Clause 4.1)

IS 7197: Performance Testing - Key Points

1. Sampling & Inspection (Clause 8.1, Appendix A)

• Floor springs are sampled as per scale of sampling (A-1).
• Inspection covers manufacture, construction, dimensions, and performance.
• Any failure in these tests deems the floor spring defective.

2. Material Specifications (Table 1, Clause 4.1)

3. Criteria for Conformity (A-2)

• Floor springs must meet all dimensional and performance requirements.
• Failure in any test = non-conformity.

Summary Diagram of Testing Flow

flowchart TD
    A[Select floor springs sample] --> B[Inspect manufacture & construction]
    B --> C[Check dimensional requirements]
    C --> D[Conduct performance tests]
    D --> E{Pass

IS 7197 - Workmanship Key Specifications & Materials for Floor Springs (Clause 4.1)

Additional Workmanship Notes:

• Material certificates must comply with corresponding IS standards.
• Lot acceptance based on permissible defective counts (Clause 2.1).
• Use specified thicknesses to ensure durability and performance.

This table ensures correct material selection and thickness for each component, critical for quality workmanship in floor springs.

IS 7197: Surface Treatment and Finishing Key Points

1. Surface Preparation (Clause 10.2, 10.2.1)

• Remove dents, burrs, sharp edges.
• Components must be pickled, scrubbed, rinsed to remove grease, rust, scale, and foreign matter.
• Applies to mild steel and cast iron parts before painting.

2. Marking (Clause 11.1)

Each floor spring must be stamped with:

• Manufacturer's name/trade-mark.
• Year of manufacture.
• Country of origin.

3. Material Treatment Specifications

• Phosphate treatment for corrosion protection of iron & steel.
• Paste filler for color coats.
• Enamel coatings (exterior, Type 2) for undercoating and finishing.
• Anodic coatings for aluminium.

4. Materials & Thickness (Clause 4.1, Table 1)

Summary Diagram: Surface Treatment Process

flowchart TD
    A[Raw Component] --> B[Remove burrs & sharp edges]
    B --> C[Pick

IS 7197 - Marking & Material Specifications for Floor Springs

Clause 11.1: Marking Requirements

Each floor spring must be stamped with:

• Manufacturer's name or trade-mark
• Year of manufacture
• Country of origin

Clause 4.1: Material Requirements for Floor Springs (Key Table Extract)

Summary:

• **Mark

IS 7197: Accessories and Instructions Key Points

Accessories (Clause 13.1a)

• Manufacturer must supply adjusting steel bars and other necessary accessories with the floor spring.

Instructions (Clause 13.1b)

• Clear fixing instructions must be provided for proper installation.

Packaging & Marking (Clause 12.1)

• Each floor spring packed in cardboard with:
  • Manufacturer's name/trade-mark
  • Quantity
  • Country of origin
  • Year of manufacture

Material Specifications (Clause 4.1, Table 1)

IS 7197: Sampling and Criteria for Conformity (Appendix A, Clauses 8.1 & 15.1)

Key Points:

• Sampling Method: Representative samples are drawn from a lot as per Appendix A.
• Lot Conformity: A lot is conforming if the number of defective floor springs in the sample is less than or equal to the permissible number (Column 3, Table 2).
• Non-conforming Lot: If defective count exceeds permissible number, the lot is rejected.

Table 2: Scale of Sampling & Permissible Defective Floor Springs

Summary:

• Sample size depends on lot size.
• Acceptance criteria: Defective units ≤ permissible number.
• Ensures quality control by statistical sampling.

flowchart TD
    A[Start: Lot Received] --> B[Select Sample Size as per Lot Size]
    B --> C[Inspect Sample for Defects]
    C --> D{Defective Units ≤ Permissible?}
    D -- Yes --> E[Lot Accepted]
    D -- No --> F[Lot Rejected]

This method ensures a standardized, statistically valid quality check for floor springs.

IS 7197: Scale of Sampling & Criteria for Conformity

1. Scale of Sampling (Table 2)

2. Criteria for Conformity

• Lot conformity: The lot passes if the number of defective floor springs in the sample is less than or equal to the permissible number in column 3.
• If defects exceed permissible limits, the lot is rejected.

Summary:

• Sampling size depends on lot size.
• Zero defects allowed for smaller lots.
• Larger lots allow limited defects.
• Sampling ensures quality control per IS 7197.

flowchart TD
    A[Start: Lot Size] --> B{Lot Size?}
    B -->|≤100| C[Sample 5, Max Defect 0]
    B -->|101-150| D[Sample 8, Max Defect 0]
    B -->|151-300| E[Sample 13, Max Defect 0]
    B -->|301-500| F[Sample 20, Max Defect 1]
    B -->|501-1000| G[Sample 32, Max Defect 2]
    B -->|>1000| H[Sample 50, Max Defect 3]
    C --> I{Defects ≤ Max?}
    D --> I
    E --> I
    F --> I
    G --> I
    H --> I
    I -->|Yes| J[Lot Conforms]
    I -->|No| K[Lot Rejected]

This ensures consistent quality assessment of floor springs per IS 7197.