Polyethylene compression reducing tee is one of the most economical and reliable fittings for creating a branch while changing size in polyethylene pipelines. Using a compression mechanism (Compression) and O-ring sealing, it installs quickly without welding and is widely used in water distribution, irrigation, low-pressure sewage, and the conveyance of light industrial fluids.
What is a polyethylene compression reducing tee?
A tee with three ports in which the main inlet is usually larger and the two outlets are smaller. Each port includes a nut, bush, split ring (Grip Ring), and O-ring so that, by hand-tightening or using a torque wrench, uniform compressive force is applied to the pipe and a dependable seal is achieved. Its main purpose is to take a branch from the main line while reducing size at the same time—without long shutdowns and without welding equipment.
Components and their roles
- Body: Made from high-quality polyethylene or durable engineering polymers; forms the flow passage.
- Nut (NUT): Tightens the assembly by turning and provides the required pressure.
- Split ring (Grip Ring): Locks onto the pipe and prevents slippage.
- Bush/support ring: Transfers load evenly to the O-ring and body.
- O-ring: Typically NBR or EPDM for leak-tight sealing.
- Internal reducing bushing: In reducing models, used to change the effective bore of the ports.
Features and benefits
- On-the-spot size reduction: Connect a larger main pipe to two smaller branches without extra fittings.
- Easy, fast installation: No electricity, heater, or welding machine required; ideal for mobile projects and quick repairs.
- Reliable sealing: O-ring with a well-designed seat effectively controls leakage.
- Mechanical and chemical durability: Good resistance to impact, abrasion, scaling, and many common agricultural/water chemicals.
- Outdoor safety: UV-stabilized options for sunlight resistance.
- Removable and reusable: Can be disassembled and reused elsewhere.
Standards and recommended operating range
- Common pressure class: PN10 to PN16 for cold water and irrigation.
- Typical service temperature: About 0 to 40 °C for water; pressure capability decreases at higher temperatures.
- Pipe compatibility: Suits PE pipes with standard SDR/outside diameter (typical water-supply series).
Common size combinations for polyethylene compression reducing tees
| Main inlet (mm) | Outlet 1 (mm) | Outlet 2 (mm) | Recommended pressure rating | Example application |
|---|---|---|---|---|
| 32 | 25 | 25 | PN16 | Branching from a field pipe to two drip lines |
| 40 | 32 | 32 | PN16 | Garden and villa water supply |
| 50 | 32 | 32 | PN10/16 | Splitting water to two irrigation blocks |
| 63 | 40 | 40 | PN16 | Sprinkler irrigation network |
| 63 | 50 | 32 | PN16 | Two outlets with different flow rates |
| 75 | 50 | 50 | PN10/16 | Rural trunk lines |
| 90 | 63 | 50 | PN10 | Secondary branching in large farms |
| 110 | 90 | 63 | PN10 | Step-down to lower-demand zones |
Note: Size combinations are highly diverse; always match the pipe’s outside diameter to the fitting catalog.
Selection and sizing guide
- Define branch flow rates: The sum of the two outlet flows must not exceed the hydraulic capacity of the main line.
- Check working pressure: Near-PN16 pressures call for bodies and O-rings with reinforced designs.
- Match pipe SDR: Identical OD alone isn’t enough; ring stiffness and wall thickness affect sealing.
- Fluid type and water quality: For water with fine sand, use proper filtration and periodically inspect the grip ring.
- Installation conditions: Consider space limits, access, and serviceability when selecting size and outlet orientation.
Step-by-step installation
- Shut off flow and secure the work area.
- Cut pipes square with proper shears or saw; lightly chamfer the edge to protect the O-ring.
- Loosen nuts and remove bush and split ring from each port.
- Place parts on the pipe in order: nut → split ring → bush.
- Lightly lubricate the pipe surface (if permitted) to ease passage through the O-ring.
- Insert the pipe to the seat depth mark inside the tee body.
- Tighten nuts first by hand, then with a wrench to the manufacturer’s recommended torque (avoid over-tightening).
- After filling and venting the line, perform pressure/leak testing.
Installation & maintenance checklist
| Item | Notes |
|---|---|
| Proper cutting & chamfering | A sharp edge can cut the O-ring and cause leaks. |
| Clean joint area | Sand/mud under the O-ring disrupts sealing. |
| Insertion depth | Each pipe must bottom out at the body seat. |
| Correct torque | Too loose = leaks; too tight = risk of body cracking. |
| Initial test | After installation, leak-test at project working pressure. |
| Periodic inspection | Outdoors, check nut tightness and O-ring condition. |
Common mistakes and how to prevent them
- Using non-standard pipe: OD mismatch complicates fit; use standard-compliant pipe.
- Skipping chamfering: Sharp pipe edges damage O-rings; a light chamfer is essential.
- Running irrigation without filtration: Abrasive particles shorten grip-ring and O-ring life; install filters.
- Incorrect torque application: Follow manufacturer guidance and use a proper wrench.
- Ignoring thermal expansion: Provide supports and expansion allowance on long runs.
Applications across projects
- Urban and rural water supply: Branching from trunk lines to end users.
- Drip and sprinkler irrigation: Dividing feed lines into blocks/zones.
- Low-pressure sewage & stormwater collection: Creating service branches in networks.
- Light industrial services: Cooling, washing, and non-corrosive fluid transfer.
Comparison with other joining methods
- Versus butt fusion: Faster install, fewer tools; however, for very high pressure and temperature, fusion can be stronger.
- Versus electrofusion: Lower cost and simpler execution; electrofusion is preferred for critical buried lines and higher pressures.
- Versus metal threaded fittings: Less corrosion and better PE compatibility; at high temp/pressure, metal threads may offer higher mechanical strength.
Factors affecting price
- Size and reduction combination: Larger size differences cost more.
- Pressure class (PN): Reinforced materials/designs increase cost.
- O-ring and internal parts quality: Better O-rings and tougher grip rings last longer.
- UV-resistant additives: Recommended for outdoor use and affect price.
- Quality control & certifications: Compliance with recognized standards improves value.
Hydraulic design tips
- Manage head loss: Abrupt reductions increase velocity; check head loss and cavitation risk.
- Avoid bending stress: Install the tee with proper supports and avoid off-axis loading.
- Plan for isolation and repair: Provide a shut-off valve and a repair coupling near the tee.
Safety notes
- Wear gloves and safety glasses during cutting and installation.
- Fully depressurize the line before opening the joint.
- In freezing environments, drain or insulate the lines.
Tamam Baha, as an active supplier of polyethylene compression reducing tees, offers a wide range of sizes and pressure classes suited to irrigation and water-distribution projects in your area. With pre-purchase technical guidance and post-installation support, choosing the optimal size and ensuring proper sealing becomes easier. Please note that Tamam Baha is not the only seller of this product, and you can choose the option that best fits your technical criteria and budget.
