injection moulded PVC socket fittings with solvent cement joints for water supplies, Part 4: Specific requirements for 90-degree tees

IS 7834 Part 4: Scope & Key Specifications for 90° PVC Tees

Scope (Clause 1):

• Covers manufacture, dimensions, tolerances, and marking for injection moulded PVC 90° tees used in water supply systems.
• Applies to sizes from 16 mm up to 315 mm diameter (expanded from earlier 160 mm).

Key Table: Laying Length (Z) for 90° Tees (Clause 2.2.2, Table 1)

Notes:

• Laying length (Z) is the critical dimension for installation, ensuring proper fit and solvent cement joint integrity.
• Tolerances are asymmetric, typically allowing more positive deviation.
• The standard complements other parts of IS 7834 covering different fittings (elbows, unions, caps).

flowchart LR
    A[Injection Moulded PVC Socket Fittings

IS 7834 (Part 4) - 1987: Key Requirements for 90° PVC Tees

1. Scope

• Specifies requirements for injection moulded PVC 90° tees used in water supply systems.
• Covers manufacture, dimensions, tolerances, and marking.

2. General Requirements (Clause 2.1)

• Material, manufacture, testing, and sampling must comply with IS 7834 (Part 1) - 1987.

3. Laying Length (Clause 2.2.2 & Table 1)

• The laying length Z and its tolerance must follow Table 1 below:

4. Marking (Clause 3.1)

• Must comply with BIS Standard Marking requirements.

flowchart LR
    A[Injection Moulded PVC 90° Tee] --> B

IS 7834 Part 4 (1987) – Key Specifications for 90° PVC Tees

1. General

• Applies to injection moulded PVC socket fittings with solvent cement joints for water supplies.
• Conforms to IS 7834 Part 1 for general material, manufacture, and testing requirements.

2. Laying Length (Clause 2.2.2 & Table 1)

• Laying length (Z) is critical for installation and must comply with specified dimensions and tolerances:

3. Marking (Clause 3.1)

• Standard Mark details as per BIS guidelines.

Summary Diagram of 90° Tee Laying Length Concept

graph LR
A[Pipe] --> B[90° Tee]
B --> C[Laying Length Z]
C --> D[Dimension + Tolerance]

Note: Always refer to IS 7834 Part 1 for general material and

IS 7834 Part 4 (1987) - Manufacture of 90° PVC Tees

Key Specifications:

• General Manufacture Requirements:
  Follow IS 7834 Part 1 (1987) for material, manufacturing methods, testing, and sampling of injection-moulded PVC fittings.

• Laying Length (Z) for 90° Tees (Clause 2.2.2):
  The laying length and its tolerance must comply with Table 1 below.

Table 1: Laying Length (Z) for 90° Tees (in mm)

Notes:

• Laying length (Z): Distance used for installation, critical for proper jointing.
• Tolerances ensure interchangeability and fit during assembly.
• Manufacturing must ensure dimensional accuracy within these limits.

flowchart LR
    A[Material & Manufacturing] --> B[Injection Moulding per IS

IS 7834 Part 4 - Key Specifications for 90° Tee (Injection Moulded PVC Socket Fittings)

1. Illustration

• Refer to Fig. 1 in Clause 2.2.1 for a typical tee illustration (not provided here).

2. Dimensions: Laying Length (Z)

3. Socket Dimensions

• Inside diameter and socket length must comply with IS 7834 Part 1 (1987).

4. Marking Requirements

• Manufacturer's name or ID mark.
• Size of fitting and class (working pressure rating).

Summary Diagram of 90° Tee Dimensions

graph LR
A[Main Pipe] -- Laying Length Z --> B[Tee Branch]
B -- Socket Length & Diameter --> C[Socket (per IS 7834 Part 1)]

This standard ensures dimensional accuracy and pressure rating traceability for injection moulded

IS 7834 Part 4 - Laying Length for 90° Tees

Key Specification (Clause 2.2.2)

• Laying length (Z) and its tolerance must comply with Table 1 below.

Table 1: Laying Length (Z) for 90° Tees

Additional Notes:

• Socket inside diameter and length follow IS 7834 Part 1 - 1987 (Clause 2.2.3).
• Marking on each tee includes:
  • Manufacturer's name/mark
  • Size and pressure class (Clause 3)

Quick Reference Formula:

• Z = Nominal laying length ± tolerance (from Table 1)

flowchart LR
    A[Pipe Size (mm)] --> B[Laying Length Z (mm)]
    B --> C{Tolerance}
    C -->|Positive| D[Add tolerance]
    C

IS 7834 Part 4 (1987) — Socket Dimensions for 90° Tees

• The inside diameter and socket length of the socket must comply with IS 7834 Part 1 (1987).
• Socket fittings are injection-moulded PVC with solvent cement joints.
• Sizes covered: 16 mm up to 315 mm.

Key Table: 90° Tee Laying Length (Z) in mm

Marking Requirements (Clause 3)

• Manufacturer's name or ID mark.
• Size of fitting.
• Appropriate class (working pressure).

Summary

• Use IS 7834 Part 1 for socket inside diameter and length.
• Refer to the above table for laying length of 90° tees.
• Ensure proper marking as per Clause 3.

If you need socket dimensions for other fittings (like elbows, tees, unions), refer to respective parts (Part 2, 3,

IS 7834 Part 4 (1987) - Marking of 90° Tee Fittings

Key Specifications for Marking (Clause 3):

• Manufacturer's name or identification mark
• Size of the fitting (nominal diameter)
• Class (working pressure rating) of the fitting

Relevant Dimensions (Clause 2.2.2 & Table 1):

Additional Notes:

• Socket dimensions must comply with IS 7834 Part 1 (1987).
• Marking ensures traceability and pressure class identification for safety and quality control.

flowchart LR
    A[90° Tee Fitting] --> B[Marking]
    B --> C[Manufacturer Name/Mark]
    B --> D[Size of Fitting]
    B --> E[Class (Working Pressure)]

This structured marking and dimensional control ensure proper identification and installation compliance per IS