Threaded Rubber Expansion Joints
A threaded rubber expansion joint is a flexible connector that absorbs vibration, noise transmission and small misalignment on small-bore lines with its twin-sphere rubber body and union ends.
It is used on threaded connections of pumps, booster sets and air conditioning units. The product range includes 8 sizes from 1/2″ to 3″; the twin-sphere design gives wide angular and lateral movement.
Main Applications
- Pump inlet and outlet connections
- Booster sets and small pressure groups
- Fan coil and AC unit connections
- Small-bore boiler room lines
- Supply lines to vibrating machines
- Systems needing noise isolation
Technical Data
| Type | Twin-sphere threaded rubber expansion joint |
|---|---|
| Sizes | 1/2″, 3/4″, 1″, 1 1/4″, 1 1/2″, 2″, 2 1/2″, 3″ (product range) |
| Connection | Union, Rc thread |
| Bellows | Special synthetic rubber (manufacturer sheet) |
| Movement | Axial −22/+6 mm · lateral ±22 mm · angular 30° (DN15–DN80) |
| Length | 165 mm (DN15) … 260 mm (DN80) |
| Operating temperature | −10 … +90 °C (parent group sheet) |
| Pressure | Falls with temperature; depending on model |
| Restriction | Not suitable for oily fluids such as oil, petrol and grease |
Material Options
| Part | Threaded · twin-sphere | Flanged · PN16 |
|---|---|---|
| Bellows | Special synthetic rubber | EPDM |
| Reinforcement | Depending on model | Nylon fabric + hard steel wire |
| Connection | Union (Rc) | Mild steel floating flange |
| Size | DN15 – DN80 | DN32 – DN300 |
Which material? Values are taken from the rubber expansion joint manufacturer sheet. The joint works efficiently when the pipe on both sides is anchored; for hot water above 90 °C and steam, braided metal hose should be preferred.
Advantages
Vibration Damping
- Cuts pump vibration
Noise Isolation
- Reduces structure-borne sound
Wide Angular Movement
- Up to 30°
Easy Installation
- Union threaded ends
Construction and Design Features
- Twin-sphere rubber bellows
- Inner fabric and wire reinforcement
- Union at both ends
- Alignment by swivel nut
Send the thread size, fluid, temperature and quantity; we will confirm a threaded rubber expansion joint from stock.
How to Choose?
- Determine size and connectionChoose the thread size of the line.
- Check the pressureAssess working pressure together with temperature.
- Fluid and temperatureConfirm water, glycol or air below 90 °C.
- MaterialRequest NBR bellows for oily fluids.
Complementary Products
Why ORFA?
Other Rubber Expansion Joints
Flanged Rubber Expansion Joints
Flanged rubber expansion joints absorb vibration, noise and small misalignments in pump and pipe lines.
Details →
Marine Type Rubber Expansion Joints
Marine type rubber expansion joints are long-body rubber bellows used to absorb vibration in ship and marine applications.
Details →Get a quote for your project
Our sales team will prepare the best solution for your needs.