diaphragm type (plastic body) float-operated valves for complex water services

IS 13049: Scope & Key Specifications

• Scope: Specifies materials, workmanship, performance, sampling, dimensions, and tolerances for diaphragm type (plastic body) float operated valves used in cold water services (up to 45°C) such as flush tanks and overhead tanks.

• Materials: As per Table 1 (Clause 5.1), all components must use specified materials ensuring durability and corrosion resistance.

• Performance Test (Clause E-2.2):

  • Valve fitted with HP seat, float removed.
  • Discharge water into container B for 140 ± 5 seconds.
  • Maintain constant pressure at seat: 0.35 ± 0.01 MPa.
  • Measure discharged water volume to verify flow.

• Valve Selection: Use the number of valves from Column 2 of Table 2 (Clause 9.2.3.1) for testing or design.

• Temperature Limit: Valves suitable for cold water up to 45°C.

Summary Table (Conceptual)

flowchart LR
    A[Valve Assembly] --> B[Remove Float]
    B --> C[Discharge Water into Container B]
    C --> D[Maintain 0.35 ± 0.01 MPa Pressure]
    D --> E[Measure Water Volume after 140 ± 5 s]
    E --> F[Verify Performance]

This standard aligns with BS 1212 (Part 3):1979 and emphasizes polymer use for sustainability.

IS 13049 Key References Summary

1. Material Specifications (Clause 5.1, Table 1):

   • Components/parts must use materials listed in Table 1 (refer IS 13049 for exact materials).

2. Valve Selection (Clause 9.2.3.1):

   • Number of valves to be selected as per Column 2, Table 2.

3. Hydraulic Pressure Test (Clause 8.6, Annex G):

   • Test setup: Cold water supply with dynamic pressure = 1 MPa.
   • Procedure: Valve held fully open, pressure increased gradually to 1 MPa, maintained for 6 ± 1 seconds.
   • Check for permanent deformation or separation.

4. Standards & Licensing:

   • BIS governs the use of the Standard Mark under the Bureau of Indian Standards Act, 1986.
   • Products with BIS mark comply with quality, inspection, and testing requirements.

Example: Hydraulic Pressure Test Setup (Annex G)

flowchart LR
    A[Cold Water Supply] -->|1 MPa Pressure| B[Pressure Gauge]
    B --> C[Valve Under Test (Fully Open)]
    C --> D[Discharge Arrangement]
    D --> E[Observe Deformation/Separation]

For detailed tables (Table 1, Table 2) and exact material grades, refer to IS 13049 full text.

IS 13049: Definitions and Key Specifications for Diaphragm Type Float Operated Valves

Key Definitions (from Clause 2.2 and related context)

• Float Operated Valve: Controls water flow by diaphragm flexing, fitted with a discharge arrangement directing water into the cistern.
• Test Pressure: 0.35 ± 0.01 MPa at the valve seat during performance testing.
• Test Duration: Water discharge measured over 140 ± 5 seconds.

Important Specifications:

• Materials: As per Table 1 (Clause 5.1), components must conform to specified materials ensuring durability and performance.
• Number of Valves: Use values from Table 2, Column 2 for valve selection (Clause 9.2.3.1).
• Temperature Limit: Suitable for cold water services up to 45°C.
• Sampling & Testing: Follow IS 2:1960 for rounding off, and IS 2500 series for sampling methods.

Test Procedure Summary (Clause E-2.2):

1. Install valve with HP seat and discharge arrangement.
2. Remove float.
3. Discharge water into container B for 140 ± 5 s at 0.35 ± 0.01 MPa.
4. Record discharged volume.

Typical Table Reference (Material Example from Table 1):

flowchart TD
    A[Water Supply] --> B[Float Operated Valve]
    B --> C[Diaphragm Flexing Controls Flow]
    C --> D[Discharge Arrangement]
    D --> E[Cistern]
    F[Test Setup] -->|Remove Float| B
    F -->|Apply Pressure 0.35 MPa| B
    F -->|Measure Discharge for 140s| G[Container B]

For detailed dimensions and valve numbers, refer to Tables 1 & 2 in IS 13049.

IS 13049 - Materials for Float Valve Components

Key Specifications (Clause 5.1 & Table 1)

• Reworked plastic material: Up to 15% of manufacturer's own clean reworked plastic from the manufacturing process is allowed; no other reworked material permitted.
• Material selection criteria (Clause 5.2): Must ensure mechanical strength, dimensional and chemical stability, and resistance to degradation under normal working conditions.

Quality Control (Clause 9.2.1)

• Valves must be inspected for material, workmanship, and construction.
• Any defect in these aspects renders the valve defective.

Summary:

• Use Polyacetal primarily for valve body and related parts.
• Discharge horn may use a variety of plastics based on application.
• Ensure materials maintain integrity under service conditions.

flowchart TD
    A[Valve Components] --> B[Valve Body, Inlet Shank, Seal, Back Nut]
    B -->|Material| C[Polyacetal]
    A --> D[Discharge Horn (if provided)]
    D -->|Material Options| E[Polyacetal, Polypropylene, Polyethylene, ABS, EVA, Others]
    F[Material Selection] --> G[Mechanical Stability]
    F --> H[Dimensional Stability]
    F --> I[Chemical Stability]
    F --> J[No degradation in normal use]

This ensures compliance with IS 13049 for float valve materials.

IS 13049 — Manufacture and Workmanship: Key Points

• Materials (Clause 5.1, Table 1):

  Component/Part	Material
  Valve body, inlet shank, valve seal, back nut	Polyacetal
  Discharge horn (if provided)	Polyacetal or polypropylene or polyethylene or ABS or EVA or other suitable material

• Use of Reworked Material:

  • Up to 15% of manufacturer's own clean reworked plastic from the process can be added.
  • No other reworked materials are permitted.

• Manufacture and Workmanship (Clause 6.1):

  • Parts must be sound and free from defects like flash, plugging, or other manufacturing flaws.

• Inspection (Clause 9.2.1):

  • All valves must be examined for material conformity, workmanship, and construction.
  • Any valve failing in these aspects is defective.

Summary Diagram: Manufacture & Inspection Flow

flowchart TD
    A[Raw Materials] --> B[Manufacturing Process]
    B --> C[Check for Defects (flash, plugging, etc.)]
    C -->|Pass| D[Assembly of Valve Components]
    D --> E[Inspection: Material, Workmanship, Construction]
    E -->|Pass| F[Approved Valve]
    E -->|Fail| G[Rejected Valve]

This ensures quality and durability of float valves per IS 13049.

IS 13049: Design and Construction - Key Specifications & Tables

1. Materials (Clause 5.1, Table 1)

• Reworked plastic material allowed up to 15% of manufacturer's own clean rework only.

2. Hydraulic Pressure Test (Clause 8.6, Annex G)

• Test Setup: Valve fitted with high-pressure seat and discharge arrangement.
• Test Pressure: Increase cold water supply pressure gradually to 1 MPa.
• Duration: Maintain pressure for 6 ± 1 seconds.
• Observation: Check for permanent deformation or separation of components.

3. Performance Test (Clause 2.2)

• Valve discharged into container under 0.35 ± 0.01 MPa pressure for 140 ± 5 seconds.
• Measure volume discharged to verify flow performance.

Summary Diagram: Test Setup for Hydraulic Pressure

flowchart LR
    A[Cold Water Supply] -->|Dynamic Pressure 1 MPa| B[Pressure Gauge]
    B --> C[Valve Under Test (Fully Open)]
    C --> D[Discharge Arrangement]
    D --> E[Container for Water Collection]

Additional Notes:

• Design ensures polymer use to conserve metal.
• Complies with BIS quality and inspection system.
• Use IS 2:1960 for rounding off test results.

For detailed dimensions and tolerances, refer to IS 2643 (Part 3) and IS 9762 for polyethylene floats.

IS 13049: Performance Requirements Summary

Materials (Clause 5.1)

• Components must use materials listed in Table 1 (refer IS 13049 Table 1 for specifics).

Discharge Arrangement (Clause 7.6.3)

• If discharge point is below valve horizontal centerline:
  • Include constantly open air inlets or backflow prevention devices.

Valve Selection (Clause 9.2.3.1)

• Number of valves to test is per Column 2, Table 2.

Performance Test Setup (Clause 8 & Annex E)

• Test rig maintains 1 m head of water at valve inlet.
• Valve fitted with Low-Pressure (LP) seat.
• Water discharges for 140 seconds from cistern at 1100 ± 1 mm above valve center.
• Measure volume collected at outlet container after test.

Automatic Cycle Test (Annex F)

• Water head: 1.00 ± 0.01 m, temperature ≤ 30°C.
• Closure force: 10 N at float arm end.
• Cycle:
  • Open valve fully ≥ 1 sec.
  • Hold open 2 sec.
  • Close valve fully ≥ 1 sec.
  • Hold closed ≤ 2 sec.
• Cycle duration ≥ 6 seconds.

Key Formula: Volume Flow (V)

[ V = A \times h \times t ]

• (A) = cross-sectional area of outlet pipe
• (h) = water head (m)
• (t) = test duration (s)

flowchart LR
    A[Cistern (Water Head 1m)] -->|Through Gate Valve| B[Valve Under Test]
    B -->|Discharge for 140s| C[Water Container]
    D[Stop Valve] -. Maintains Water Level .-> A

For detailed values, refer to Tables 1 & 2 and Figures 4 in IS 13049.

IS 13049: Performance Tests Summary

1. Endurance Test (Clause 8.5, Annex F)

• Test Setup: Automatic cycle operation of float arm/assembly.
• Water Head: Maintain 1.00 ± 0.01 m water head, temperature ≤ 30°C.
• Force: Apply 10 N closure force at float arm end.
• Cycle:
  • Open valve fully in ≥ 1 second.
  • Keep open for 2 seconds.
  • Close valve fully in ≥ 1 second.
  • Keep closed for max 2 seconds.
• Cycle duration: ≥ 6 seconds total.
• Purpose: Verify valve can withstand repeated operation.

2. Minimum Flow Test (Clause 8.4, Annex E)

• Test Rig: Cistern with 1.1 m water head above valve inlet.
• Duration: Valve discharges for 140 seconds.
• Measurement: Volume collected in container B.
• Setup includes: 15 mm copper pipe, gate valve, LP seat installed.
• Diagram: (Fig. 4 shows arrangement with cistern, valve, container, stop valve)

3. Anti-Siphonage and Endurance Testing (Clause 8.3)

• Frequency: At least once per month per sample.
• If failure: Corrective action + repeat all performance tests.

Key Dimensions & Parameters

flowchart LR
    A[Cistern A - Water Source] -->|15 mm pipe| D[Valve Under Test]
    D -->|Discharge| B[Container B - Collect Water]
    C[Stop Valve] -. Controls water level .-> A
    E[Gate Valve] -. Controls flow .-> D

This ensures reliability and compliance with IS 13049 valve performance requirements.

IS 13049: Sampling and Criteria for Conformity

Key Points from Clause 9.1 & 9.2:

• Sampling: Valves are selected randomly from each lot as per IS 4905:1968 for randomness.
• Testing: Samples from each lot are tested separately to verify conformity.
• Acceptance Criteria: A lot is accepted if defective items ≤ acceptance number from Table 2.

Table 2: Scale of Sampling and Criteria for Conformity

Summary:

• For example, if the lot size is 600, test 20 valves.
• If ≤ 1 valve is defective, the lot conforms.
• If defects exceed acceptance number, the lot is rejected.

flowchart TD
    A[Start: Identify Lot Size] --> B{Lot Size?}
    B -->|<=100| C[Sample 5 valves]
    B -->|101-150| D[Sample 8 valves]
    B -->|151-500| E[Sample 13 valves]
    B -->|501-1000| F[Sample 20 valves]
    B -->|>1000| G[Sample 32 valves]

    C --> H[Count Defective Items]
    D --> H
    E --> H
    F --> H
    G --> H

    H --> I{Defects ≤ Acceptance Number?}
    I -->|Yes| J[Lot Accepted]
    I -->|No| K[Lot Rejected]

This ensures quality control by statistically verifying valve conformity in batches.

IS 13049 — Marking Requirements for Valves

Key Marking Specifications (Clause 10.1)

Every valve shall be permanently and legibly marked with:

• Source of manufacture (manufacturer's name or trademark)
• Nominal size (e.g., 15 mm)
• Entry type (side or bottom entry)
• Valve class/type (e.g., diaphragm type)
• Date of manufacture or lot number

Use of Standard Mark (Clause 10.2)

• Valves may be marked with the BIS Standard Mark.
• This mark assures compliance with IS 13049 under BIS quality control and inspection.
• Use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986.

Testing Reference (Clause 8.6, Annex G)

• Hydraulic pressure test at 1 MPa for 6 ±1 seconds.
• Check for permanent deformation or component separation.

Summary Table for Marking

flowchart LR
    A[Valve] --> B[Marking]
    B --> C[Manufacturer]
    B --> D[Nominal Size]
    B --> E[Entry Type]
    B --> F[Valve Class/Type]
    B --> G[Date/Lot Number]
    B --> H[Standard Mark (optional)]

This ensures traceability, quality assurance, and compliance with IS 13049.

IS 13049: Test for Screw Threads for Inlet and Backnuts Shanks

Key Specifications and Test Procedure (Annex A, Clauses 7.1 & 7.4)

• Inlet Shank Length: Minimum 48 mm.
• Backnuts: Two backnuts with parallel internal threads per IS 2643 (Part 3):1975, same size as float valves.
• Torque Test:
  • Apply a torque of 15 Nm on the backnut using a snug-fitting spanner.
  • Acceptance Criteria: No visible distortion of threads or flats of the hexagon.

Thread Compliance

• Threads on backnuts and inlet shank must conform to IS 2643 (Part 3):1975.
• Must pass the torque test with no damage.

Summary Table: Torque Test for Backnuts and Inlet Shank Threads

flowchart LR
    A[Inlet Shank ≥ 48 mm] --> B[Two Backnuts (IS 2643)]
    B --> C[Torque Test: 15 Nm]
    C --> D{No Visible Distortion?}
    D -->|Yes| E[Threads Pass Test]
    D -->|No| F[Reject/Retest]

Note: This test ensures mechanical integrity and leak-tightness of inlet connections in valves.

IS 13049: Deflection Test for Float Valve Assembly (Clause 7.5.3 & Annex B)

Key Specifications:

• Initial deflection limit: ≤ 25 mm immediately after applying load.
• Additional deflection after 28 days: ≤ 12 mm.
• Total deflection limit: ≤ 37 mm (initial + after 28 days).

Test Setup (Annex B):

• Remove diaphragm; replace with rigid steel disc of same diameter.
• Fix valve assembly into a 19 mm thick rigid wall.
• Position inlet shank so union nut end is 19 mm behind the wall.
• Apply a load of 4.4 N in the closing direction at the float connection.
• Measure deflection immediately and after 28 days under load.

Procedure Summary:

1. Apply 4.4 N load gradually.
2. Record initial deflection.
3. Keep loaded for 28 days.
4. Record deflection again.
5. Ensure deflections meet limits.

Deflection Limits Summary Table:

Diagram: Valve Assembly Deflection Test Setup (Fig. 2)

flowchart LR
    Wall["Rigid Wall (19 mm thick)"]
    Valve["Valve Assembly with steel disc"]
    Load["4.4 N Load Applied at Float Connection"]
    Deflection["Measure Deflection"]

    Wall --> Valve
    Load --> Valve
    Valve --> Deflection

For detailed flow and pressure testing, see Annex E and Annex F for minimum flow and cyclic operation tests respectively.

IS 13049: Shut-Off Test Key Points

• Purpose: Verify valve remains closed under specified minimum test pressures without leakage.

Shut-Off Test Pressures (Clause 8.2):

• Test Setup (Clause 2.1.1 & Fig. 4):

  • Test rig maintains constant pressure: 0.35 ± 0.01 MPa (for LP seat).
  • Valve connected via 15 mm copper pipe and gate valve.
  • Float immersed to half its volume.
  • Water container and pressure regulating valve used.

• Test Conditions:

  • Valve assembled in working condition, no flow restrictions.
  • Valve must remain closed against the test pressure.
  • Duration: As per hydraulic test (Clause 8.1), typically 60 ± 10 seconds at 2.0 ± 0.025 MPa (for hydraulic test).

Summary Table for Valve Testing:

flowchart LR
    A[Test Rig] -->|15 mm Copper Pipe| B[Gate Valve]
    B --> C[Valve Under Test]
    C --> D[Float immersed half volume]
    A -.-> E[Water Container]
    A -.-> F[Pressure Regulating Valve]

Note: Shut-off test ensures valve integrity under pressure without leakage; critical for safety and performance verification.

IS 13049: Low Pressure Seat Minimum Flow Test Key Points

Test Setup (Annex E, Clause 8.4)

• Test rig maintains 1.00 ± 0.01 m water head at valve inlet.
• Valve fitted with Low Pressure (LP) seat.
• Water flows from a cistern (A) through a 15 mm copper pipe and gate valve to the valve under test.
• Water discharged into container (B) for 140 seconds.
• Maintain water level in cistern A at 1.00 m above valve inlet center during test.
• Measure volume collected in container B after 140 seconds.

Test Conditions

Shut-Off Pressure (Clause 8.2)

Typical Test Sequence (Annex F, Clause 8.5)

1. Fully open valve in ≥1 sec.
2. Keep open for 2 sec.
3. Fully close valve in ≥1 sec.
4. Keep closed ≤2 sec.
5. Repeat cycle ≥6 sec duration.

Diagram Summary (Fig.4)

flowchart LR
    A[Cistern (Water at 1m head)] -->|15mm copper pipe + gate valve| D[Valve Under Test (LP seat)]
    D --> B[Water Container (Measure volume)]
    C[Stop Valve] --- A

This test ensures the valve seat allows minimum leakage flow under low pressure (0.35 MPa) and verifies valve operation under controlled flow and pressure conditions.

IS 13049 - Test for Hydraulic Pressure on Discharge Arrangements (Clause 8.6 & Annex G)

Key Specifications:

• Test Pressure: 1 MPa (10 bar) dynamic hydraulic pressure.
• Duration: Maintain pressure for (6 ± 1) seconds.
• Condition: Valve fitted with high-pressure seat and discharge arrangement, held fully open.
• Acceptance: No permanent deformation or separation of components.

Test Setup:

• Cold water supply with a pressure gauge immediately upstream of the valve.
• Gradually increase pressure to 1 MPa.
• Observe and record any permanent deformation or separation.

Summary Table (Annex G):

Important Notes:

• If discharge point is below valve centerline, air inlets or backflow preventers must be incorporated (Clause 7.6.3).
• This test ensures discharge arrangements withstand operational hydraulic stresses without failure.

flowchart LR
    A[Cold Water Supply] --> B[Pressure Gauge]
    B --> C[Valve with Discharge Arrangement]
    C --> D[Hold Valve Fully Open]
    D --> E[Increase Pressure Gradually to 1 MPa]
    E --> F[Maintain Pressure for 6 ± 1 seconds]
    F --> G{Permanent Deformation or Separation?}
    G -- No --> H[Test Passed]
    G -- Yes --> I[Test Failed]

This test is essential for quality assurance of valves under hydraulic load per IS 13049 standards.