Compounding
We manufacture a broad range of standard compounds and can offer our own designs to suit your requirements as well custom mix your own formulations. In addition to volume supplies of compounds from common polymers we can provide low volumes of specialist compounds including silicones.
Compound can be supplied as calendered sheet. pip strip, slab or wig-wag sheeting.
Special Belting and Sheeting Products
An extensive range of proprietry and custom designed conveyor belt and sheeting products incorporating a range of specialist elastomers and reinforcement materials . We welcome the chance to design products specifically to match your requirements. We can offer the full range of finishes.
General rubber products
Moulded and fabricated products including press blocks and slave pads, diaphragms, sealing tapes, strip and cut shapes.
Other products include Neoprene aquatapes for use in the fabrication of drysuits, high performance and speciality erasers, bar runners.
Vibration Control
Vibration, shock and noise are important issues in many areas of engineering and product development. We can offer of solutions to your problems including our range of visco-elastic polymers.
These materials have a low creep rate compared to other polymers and offer superior damping coefficient over a very wide temperature range. They can absorb shock efficiently for millions of cycles.
Visco-elastic means that the materials exhibit properties of both liquids (viscous solutions) and solids (elastic materials).
They have the properties of thermoset, polyether-based polyurethane material. They combine shock absorbtion. good memory, vibration insulation and vibration damping characteristics.
In addition it is a very effective acoustic damper and absorber. While other materials can offer one of these characteristics we can combine them all in a stable material with a long fatigue life.
We can assist you from idea generation through to full production and supply these materials in either sheet form or as moulded components.
Sorbothane
Engineered solutions to vibration, shock and noise.
Introduction
Sorbothane is a proprietry, visco-elastic polymer. Visco – elastic means that a material exhibits properties of both liquids and solids.
Sorbothane is a thermoset, polyether-based, 'super-soft' polyurethane. It is ROHS and WEEE compliant.
Sorbothane combines shock absorption. good memory. vibration isolation and vibration damping characteristics. In addition, Sorbothane is a very effective acoustic damper and absorber. While a wide range of materials exhibit one of these characteristics. Sorbothane combines them all in a stable material with a long fatigue life.
- Sorbothane is designed to absorb energy – it converts friction to heat and disperses it.
- Sorbothane has a low creep rate compared to other polymers (rubber, neoprene, silicone etc.)
- Sorbothane has a superior damping coefficient, over a wide temperature range compared to any other polymer.
- Unlike fluid based shock absorbers or foam products Sorbothane absorbs shock for millions of cycles
Note that Sorbothane is used in a range of proprietry sports and medical products including shock absorbing insoles. These products are available from Mobilis Healthcare and details of your nearest stockist can be found at www.mobilishealthcare.com
Custom Solutions
Although a range of standard products is available, Sorbothane can manufacture custom designed solutions to your requirement. Tooling costs where required are relatively inexpensive or you can manufacture your own solution using sheeting, strip. disc and block products listed below.
Electronics
Sorbothane is widely used to isolate delicate electronics - printed circuit boards, LCD’s disk drives and other devices.
Applications include rocket launchers and wind turbines.
Shock Absorbers
Sorbothane is designed to absorb energy. it does not compress and it returns to its natural shape time and time again after contraction. dilation and distortion. A small amount can deliver an improvement.
Acoustics
The Sorbothane hemispheres are used throughout the world in the highest quality audio equipment. In addition we can offer custom designed solutions to improve your system.
Gaskets
Sorbothane is a popular material for gaskets because of its chemical resistance, its ability to conform to irregular surfaces. its low creep and its reusability. Its natural tackiness makes it easy to install. Gaskets can be made from sheet material or produced to order.
Procedure for selecting a vibration isolator.
- Determine the load (weight) of the unit that requires isolation. Divide the weight of the system by the number of isolators to be used to establish the load per isolator.
- Determine the lowest critical frequency (excitation frequency) of the system e.g. the rpm of the motor. the rate at which a cylinder strokes or the output speed of a reducer. Divide minute-based information to by 60 to convert to hertz (cycles per second).
- Select an appropriate isolator by using the information charts shown on the website. Generally an appropriate isolator will create a system natural frequency at least one third lower than the excitation frequency. For instance, if the source of the vibration is an 1800 RPM motor. then the excitation frequency is 1800/60 = 30 hertz. The resultant damped natural frequency should be 20 hertz or less.
- Select the isolator that meets the technical and physical requirement s of your system. In addition to a part number. you must also specify the durometer of the Sorbothane part required to get the specified load rating. Do not oversize isolators. Oversized isolators raise the natural frequency and reduce the effectiveness. Sorbothane will be supplied as black coloured material although for large volume orders we can offer a range of colours.
- Remember: Sorbothane works best in compression and therefore if you have a tension application then bushings are the best option.
Durometer
Durometer is a measure of relative stiffness and is used to compare polymers.
Sorbothane is softer than rubber and most other polymers. Sorbothane is measured on the Shore '00' scale.
Most types of rubber and other polymers are specified using the shore 'A' or Shore 'D' scales. In comparing stiffness, be aware of the scale being used for the material in question.
The softest Sorbothane, 30 durometer, is used for high frequency. highest damping and low temperature (less than -20 degree C). It has been described as having the consistency of wet chewing gum but with the memory of its original shape.
The 70 durometer Sorbothane is used for high performance isolation for low frequencies (less than 500 herz) or where material toughness is a key requirement.
50 durometer Sorbothane is a compromise in strength and isolation with high damping.
The stiffness comparison values in the attached chart are approximate and should be used only as a guide
| A | B | C | D | O | OO |
|---|---|---|---|---|---|
| 100 | 85 | 77 | 58 | ||
| 95 | 81 | 70 | 46 | ||
| 90 | 76 | 59 | 39 | ||
| 85 | 71 | 52 | 33 | ||
| 80 | 66 | 47 | 29 | 84 | 98 |
| 75 | 62 | 42 | 25 | 79 | 97 |
| 70 | 56 | 37 | 22 | 75 | 95 |
| 65 | 51 | 32 | 19 | 72 | 94 |
| 60 | 47 | 28 | 16 | 69 | 93 |
| 55 | 42 | 24 | 14 | 65 | 91 |
| 50 | 37 | 20 | 12 | 61 | 90 |
| 45 | 32 | 17 | 10 | 57 | 88 |
| 40 | 27 | 14 | 8 | 53 | 86 |
| 35 | 17 | 12 | 7 | 48 | 83 |
| 30 | 12 | 9 | 6 | 42 | 80 |
| 25 | 6 | 35 | 76 | ||
| 20 | 28 | 70 | |||
| 15 | 21 | 62 | |||
| 10 | 14 | 55 | |||
| 5 | 8 | 45 |
Bushings
Sorbothane bushings can isolate vibration and absorb shock.
Using two bushings together or a bushing and washer(s), you can create a floating bolt that isolates the unit from any metal to metal contact.
Different durometers allow for different spring rates. Load ratings assume a 10-20% deflection of the material. This deflection is achieved by a combination of the system weight and the connecting bolts.
Do not over tighten the connecting bolts as this defeats the intended vibration isolation and shortens the component life. Use high quality (thread deforming) lock nut or doubled jam nuts to prevent vibration from loosening the bolt.
Unlike other Sorbothane products, bushings may be used in tension connections.
Hemispheres
Sorbothane hemisphere mounts provide a quick, cost effective method of isolating audio equipment and small machinery.
Place the hemisphere under the unit to be isolated with the curved surface upwards. Expect a 20-30% deflection when loaded. Under-loading results in poor isolation. All sizes are available with pressure sensitive adhesive (psa).
Stud Mounts & Bumpers
These products are for applications with lower shear to compression ratios. They are designed for use in compression.
Use high quality (thread deforming) lock nuts or doubled jam nuts to assure your connections do not vibrate loose.
Isolation Rings
Sorbothane isolation rings are ideal for heavy load applications that require a low system natural frequency. Typical applications include pallet isolators, sensitive hardware, and heavy machinery isolators.
Multi-Axis Isolator – Hard Drive Corner pad
The multi axis isolator, part number, was developed for large diameter memory storage devices. The Sorbothane is encapsulated between two brass housings. It provides shock and vibration attenuation in all directions.
Anti-vibration Levelling Mounts
Sorbothane anti-vibration levelling mounts provide both levelling and vibration isolation. They are designed to handle a wide range of loads and varying environmental conditions.
Major benefits of the mounts include their ability to isolate a system from unwanted vibration and resonance by lowering the natural frequency of the system.
The dual urethane compounds compliment each other to provide a high degree of vibration and shock damping.
Sheet products
All sheet and strip products are also available with pressure sensitive adhesive on one or both sides and in either 30, 50 or 70 durometer - contact the factory for prices and advice on which psa you require. Sheets can be cut by knife or scissors and we can offer die cut parts as required but note that die cut materials will have a concave edge.
Water jet cutting is available to provide a clean edge.
Sorbothane is an effective material for gaskets because of its chemical resistance, conformability to irregular surfaces, low creep and re-usability. Its natural tackiness makes it easy to install.
In designing your own anti-vibration products from sheet material note the following;
- A large lightly loaded sheet will have a high spring rate and will not deflect sufficiently to provide good isolation. Over compression will shorten material life. The proper compression range is 5 to 20 percent depending on the shape factor. The shape factor is the ratio of contact surface (one side) divided by perimeter area.
- Small circular circular pieces and rings deform more effectively than squares and rectangles and this deformation improves the isolation.
- The thicker the sheet the lower the natural frequency. You need a sheet at least 25mm thick to take the natural frequency down to 10 hertz.
| Part No | Size |
|---|---|
| SPS5050-2.5 | 500 x 500 x 2.5mm |
| SPS5050-3 | 500 x 500 x 3mm |
| SPS5050-4 | 500 x 500 x 4mm |
| SPS5050-5 | 500 x 500 x 5mm |
| SPS5050-6 | 500 x 500 x 6mm |
| SPS5050-8 | 500 x 500 x 8mm |
| SPS5050-10 | 500 x 500 x 10mm |
| SPS5050-12 | 500 x 500 x 12mm |
| SPS9840-8 | 980 x 40 x 8mm |
| SPS1005-12 | 1000 x 50 x 12mm |
| SPS5035-30 | 500 x 35 x 30mm |
| SPS504-50 | 500 x 40 x 50mm |