How to Choose a Cylindrical Rubber Vibration Isolator: Structure, Specs, Selection Tips and Applications
2026/10/13
Cylindrical Rubber Vibration Isolators: A Reliable Foundation for Quieter Machines
Rotating equipment such as motors, pumps, fans and generator sets produce constant vibration. When a machine is bolted rigidly to the floor, that energy travels through the structure, loosens bolts, wears bearings and turns floors into loudspeakers. A cylindrical rubber vibration isolator - also called a cylindrical rubber mount - places an elastic natural-rubber layer between the machine and its base and cuts the vibration path. These mounts are made by JIUFU (Shanghai Songjiang Jiufu Shock Absorber Co., Ltd.) in Shanghai, China.
1. Structure and Working Principle
The mount pairs an elastic natural-rubber (NR) body with white galvanised steel fittings, bonded in a single vulcanised moulding. M6/M8/M10 studs or threaded inserts fix it to both machine and base. Under load the rubber is stressed in compression and shear, converting vibration into a small amount of heat and blocking transmission into the structure.
Section Q&A
Q: How does it reduce vibration?
A: The rubber deforms as the machine moves, turning vibration energy into heat and breaking the path into the floor and frame.
Q: Will the rubber separate from the metal?
A: No - the one-piece vulcanised bond reaches about 40 kg/cm2 adhesion, and grade 8.8 bolts keep the mount firmly assembled.
2. Product Series
- VV: double male stud (male-male) for clamping machine to base
- VD: male-female, for one-sided mounting
- DD: compact female-female for small motors, pumps and instruments
- DE / VE: threaded studs on a rubber body; VE covers M8/M10/M12
Section Q&A
Q: Which series fits my machine?
A: Follow the fixing points - two studs need VV, one stud needs VD, two internal threads in a tight space need DD. Send a drawing and we will confirm.
3. Key Specifications
| Item | Typical value |
|---|---|
| Series | VV (double male stud), VD (male-female), DD (female-female), DE / VE |
| Elastic element | Natural rubber (NR), eco-friendly, ROHS compliant |
| Hardness | Stated in IRHD, selectable by load |
| Moulding | One-piece vulcanised moulding |
| Metal fittings | White galvanised steel to UNI-ISO 2081 |
| Thread sizes | M6 / M8 / M10 / M12 (custom available) |
| Operating temperature | -40C to +80C |
| Rubber-to-metal adhesion | About 40 kg/cm2 |
| Fasteners | Grade 8.8 high-strength bolts |
| Plating salt-spray test | 96 hours (standard is 48 hours) |
| Quality / certification | ISO9001; some models ROHS compliant |
| Origin / brand | Shanghai, China / JIUFU |
Section Q&A
Q: How do I choose the hardness?
A: Balance load and isolation - harder carries more load with less movement, softer isolates better. Choose by your point load.
4. Benefits and Applications
- Lower structure-borne noise and vibration
- Longer life for bearings, seals and fasteners
- Stable from -40C to +80C; resistant to ageing, heat, wear, moisture and oil
- Eco-friendly rubber; no separate damper or lubrication
- Simple bolt-down installation
Typical uses include pumps, fans and air-handling units, generator sets, motors and inverters, compressors and centrifuges, and vibration-sensitive instruments - usually machines running above 1200 rpm.
Section Q&A
Q: How much quieter will it be?
A: It removes the structural route that carries low-frequency rumble into the building. With correct sizing the plant room is clearly quieter, though the exact figure depends on load and installation.
5. Selection and Installation
Convert the equipment weight plus dynamic load into a load per support, then match hardness and size to the running speed and space.
- Size each mount by point load - avoid too soft or too hard
- Confirm thread and height match the mounting points
- Allow for temperature, oil and chemicals
- Keep the system's natural frequency clear of the machine speed
Section Q&A
Q: How do I size the mount?
A: Give us the total weight, number of support points and running speed; we will recommend the right model and hardness.
6. Quality Assurance
JIUFU products meet the ISO9001 quality system, with some models ROHS compliant. The plated finish passes a 96-hour salt-spray test (double the usual 48 hours), rubber-to-metal adhesion is about 40 kg/cm2, and fasteners are grade 8.8. We also support reverse engineering with 3D drawing approval.
Section Q&A
Q: Can you produce to my sample?
A: Yes - send a sample and we will reverse-engineer it, scan its features and draft 3D drawings for approval.
7. Supply and Delivery
| Item | Details |
|---|---|
| MOQ | 10 - 100 pcs depending on model |
| Reference price | From about USD 0.20 each |
| Lead time | About 5 - 8 working days |
| Payment | T/T |
| Packaging | Carton |
| Supply capacity | About 1,000,000 pcs per year |
Section Q&A
Q: What are the MOQ, lead time and payment terms?
A: Typically 10-100 pcs, about 5-8 working days, and payment by T/T; custom orders are quoted individually.
Conclusion
A cylindrical rubber vibration isolator is small but makes a big difference to steady operation and noise control. Choose the right series and rating, install it correctly, and rely on tested quality. Send us your equipment details for a matched recommendation.
