Polyethylene compression tees are among the most commonly used threaded fittings for creating reliable branches, changing direction, and combining lines in piping networks. With quick assembly, dependable sealing, and the ability to be opened and reassembled multiple times, they are an economical, low-risk solution for irrigation, water supply, and industrial applications.
What is a polyethylene compression tee and what are its components?
A polyethylene compression tee has three outlets—either concentric or eccentric—that lock and seal onto PE pipe via a gripper ring and an elastomeric O-ring. Its structure typically includes the body, insert/spigot, O-ring, gripper ring, and nut.
| Component | Function | Common material | Selection notes |
|---|---|---|---|
| Body | Withstand pressure and hold the assembly | Reinforced PP or POM | UV-stable for outdoor installations |
| Insert/Spigot | Guide the fluid and support the O-ring | PP or POM | Smooth bore for lower pressure drop |
| O-ring | Sealing | NBR or EPDM | Choose by temperature and fluid type |
| Gripper ring | Mechanical lock on the pipe | Reinforced POM/PA | Uniform engagement with the pipe |
| Nut | Apply preload and final lock | Reinforced PP | Intact threads = faster assembly |
Types of polyethylene compression tees
Female compression tee
All three ports have internal threads for connection to threaded fittings, manifolds, and valves; proper thread engagement length and thread sealant (e.g., suitable PTFE tape) are essential to prevent leakage.
Male compression tee
Provides one or more external threaded outlets to connect to metal/polymer threaded fittings. When joining to galvanized parts, ensure coaxial alignment and tighten gradually to avoid excess stress.
Reducing compression tee
Used to change branch size; for example, a 40 mm inlet with two 32 mm outlets. When designing the network, account for pressure loss due to diameter changes and the number of fittings.
Equal compression tee
All three outlets have the same size; the most common choice in pressurized irrigation and rural water-supply networks.
Main applications
- Pressurized irrigation (sprinkler and drip) in farms, orchards, and greenhouses
- Urban and rural water-supply systems and subscriber laterals
- Building services (yards, green roofs, water storage)
- Light industrial wastewater and storm-water collection
- Conveying certain chemicals compatible with the polymer and selected O-ring
- Aquaculture and fisheries, supply to ponds and recirculating systems
Guide to size, pressure class, and temperature
- Pipe size: Match the metric OD series (e.g., 20, 25, 32, 40, 50, 63, 75, 90, 110 mm).
- Pressure class: PN10 and PN16 are common at 20 °C; allowable pressure decreases as temperature rises.
- Fluid and temperature: For chemicals or temperatures above ambient, select the O-ring type (NBR/EPDM) per the manufacturer’s guidance.
- Installation environment: Prefer UV-resistant, dark-colored bodies for outdoor use.
| Size (mm) | Typical pressure class range | Suggested application |
|---|---|---|
| 20–32 | PN10 / PN16 | Irrigation branches and domestic water laterals |
| 40–63 | PN10 / PN16 | Risers, light and medium mains |
| 75–110 | PN10 (sometimes PN16) | Trunk lines, manifold and tank inlets |
The above values are common and may vary with network design, temperature, and manufacturer specifications.
Installation steps on PE pipe
- Shut off and make safe: Drain and dry the line.
- Clean, square cut: Use proper shears/saw; no burrs.
- Light chamfer and mark insertion depth: Slightly chamfer the inner edge and mark the insertion depth to protect the O-ring.
- Disassemble nut and stage parts: Remove the nut and gripper ring and place them on the pipe in the correct order.
- Approved lubrication: If needed, use an elastomer-compatible lubricant (avoid aggressive petroleum oils).
- Insert to depth and tighten the nut: Push the pipe to the mark, hand-tighten the nut, then tighten evenly with an appropriate wrench.
- Seal test: Pressurize the network gradually and check for leaks.
Technical notes and common mistakes
- Over-tightening the nut: Can damage threads or O-ring; even, gradual tightening is better.
- Misalignment: Pipe offset causes intermittent leaks; use proper supports and clamps.
- Skewed cut/sharp edge: Can nick the O-ring; clean cut and gentle chamfer are essential.
- Material mismatch: Wrong O-ring for specific fluids (chlorinated/hot) shortens seal life.
- Mechanical loading: Suspending pipe/valve weight on the tee leads to fatigue and leakage; provide supports.
Maintenance, inspection, and quick troubleshooting
- After commissioning, raise pressure and inspect all joints for moisture.
- Each season, check nut tightness and thread condition.
- Minor leaks are often solved by cleaning the O-ring and re-assembling.
- After severe impact or freezing, inspect the gripper ring and replace if cracked.
Compression vs. electrofusion and butt-fusion
- Compression advantages: Fast installation without fusion machines; re-usable; ideal for repairs.
- Limitations: Not the first choice for very high pressures and temperatures; requires mechanical care during installation.
- Electrofusion/butt-fusion: Uniform, permanent sealing for higher pressures/large diameters; higher cost and time, specialized equipment required.
Factors affecting price
- Size and pressure class; type (female/male/reducing/equal)
- Body resin grade and quality of gripper ring and O-ring
- UV resistance and thread quality
- Packaging, after-sales support, and market availability
Quick selection guide for common scenarios
- Orchard drip irrigation: Equal compression tees in 16–32 mm for branches; UV-resistant bodies.
- Yard/villa water supply: Female compression tees for valves/manifolds; PN16 pressure class.
- Connections to metal: Male compression tees with precise threads and proper thread sealant.
- Branch size reduction: Reducing compression tees while controlling pressure loss and fitting count.
Hydraulic design notes
- Minimize changes in direction and number of fittings to reduce energy loss.
- In long networks, use manifolds and multiple tees instead of very long chains of fittings.
- Where vibration or water hammer is likely, provide anti-vibration supports and suitable air valves.
TamamBaha supplies a wide range of polyethylene compression tees (female, male, reducing, and equal) with verified authenticity and technical advice. While we aren’t the only seller in the market, our goal is to help you choose and install the right parts so projects across your region run with minimal downtime—delivering a clear, professional buying experience for contractors, growers, and facility technicians.
