Precision Equipment

 

Precision equipment manufacturers, end users and everybody interested in precise production or accurate measuring results find complete solutions at Fabreeka.

 

Whether in metrology with the need for CMM isolation (coordinate measuring machine) or laboratory equipment isolation for microscopes, Fabreeka is a proven and trusted partner in this and many other fields to provide customers with PAL and PLM low frequency vibration and shock isolation systems to maintain the designed accuracy of your equipment.

 

Some applications require custom systems and structural analysis and design of the support structures and frames used in conjunction with the isolation system and integrated in the machine design. Fabreeka’s experts are here to support you in those cases as well. Add their experience from countless successful projects to your task and let their customer-specific solutions together with high-quality products exceed your requirements. With decades of experience in foundation isolation, Fabreeka has all the answers to your questions from initial consultation to complete turnkey solutions.

 

Find out more reasons why Fabreeka can make an important difference in this field in which the degree of accuracy required for precision machine tools is ever-increasing.

 

Precision Manufacturing

 

Precision manufacturing is needed for many different industries such as aerospace, industrial, medical, military, semiconductor and many others. There, the equipment that cuts, turns, polishes and positions with nanotechnology can provide finishes and measurements within microns and even angstroms.

 

To achieve the best results possible with the equipment in every environment, Fabreeka has developed matching isolation and foundation products. Working with and at CNC machines or precision lathes, among many others, can be optimized by incorporating Fabcel pads, Fabcel Lev-L mounts, or Fabcel LeveLers.

 

When it comes to ultra-precision equipment being used in many industries including semiconductor wafer processing, optics and lens manufacturing and non-standard material machining processes, low frequency pneumatic Precision-Aire Leveling isolators (PAL) provide superior low frequency vibration isolation. Customers worldwide rely on Fabreeka PAL isolators, knowing that they meet the critical needs of metrology instruments, electron microscopes, inspection stations and other precision manufacturing equipment.

 

Laboratory

 

Laboratory work is a synonym for precision work where laboratory equipment isolation is a must. Professionals using tabletop microscopes and electron microscopes for biomedical research, semiconductor manufacturing or other tasks want the highest accuracy and the best resolution. To prevent human footfalls and structural vibration from decreasing performance and accuracy of their microscopes, many companies and institutions use PAL low frequency, pneumatic isolation systems which provide attenuation not only in laboratories and clean-rooms but wherever laboratory equipment isolation is on the agenda.

 

Analytical balances and precision scales also need stable work conditions for accurate measuring. Here, Fabreeka offers pneumatic isolation products and active systems for added vibration reduction to rule out that even small oscillations or vibration that can alter weight results go unnoticed by lab personnel. This could be the case when equipment is moved across the laboratory floor, heavy traffic outside affects the building or other activities in other areas of the building create vibration.

 

MRI and NMR become more and more important to study humans and materials. Fabreeka is committed to the science of MRI vibration isolation, working both ways with products that reduce the vibration coming from the environment and also the induced MRI vibration into the building. Thus, Fabreeka has provided customers with vibration isolation solutions for all types of high resolution MRI, NMR and Cryostat equipment ranging in size from 300 MHz to 900 MHz. All pneumatic isolator hardware for NMR applications is made non-magnetic using stainless, aluminum or brass and is designed to interface with the existing magnet support brackets at the desired height. MRI vibration isolation solutions include vibration measurements and the design of the support structures, including structural and dynamic analysis.

 

Metrology

 

Metrology is a fascinating field with steady increases in measuring speed and accuracy of Coordinate Measuring Machines (CMM) and optical equipment. Since vibration is one environmental factor which can compromise a CMM’s accuracy and repeatability, Fabreeka has extensively studied allowable vibration criteria and put a lot of work in developing Vibration Site Survey and Analysis services to help customers determine if they need CMM isolation or not. When it is the case, typically low frequency vibration of less than 50 Hz requires attenuation. Fabreeka pneumatic isolators such as PAL Isolators and PLM Mounts provide significant CMM isolation and for other metrology equipment requiring low frequency vibration control.

 

Along with the standard pneumatic isolation systems that let most CMM function properly, Fabreeka systems can also be custom-made to be integrated into the machine. When larger CMM require foundations, Fabreeka is the number one resource for pneumatic isolators or pad isolators for foundation isolation. Fabreeka can also offer a foundation turnkey solution including project management, demolition, foundation design and construction.
Testing

 

Fabreeka has a leading role in providing vibration isolation systems and design techniques to meet the increasing demands of automotive, aircraft and aerospace testing in simulated environments. The company has been providing vibration isolation and shock control products for the past decade, utilizing combined expertise for customized projects and turnkey solutions.

 

In doing so, the solutions for auto testing include the design of test equipment support foundations and their reaction masses together with structural and dynamic analysis. Applications range from dynamometers, rolling road isolation, road simulators, multi-axis shaker tables to many kinds of other test equipment.

 

To support engineers in aircraft testing, Fabreeka has designed a number of soft support systems using standard and custom pneumatic isolators for ground vibration testing, while the company provides low frequency vibration isolation systems for critical testing applications in the aerospace and defense industry, which require ultra-low frequency isolation and vacuum chamber isolation.

 

Additionally, Fabreeka provides solutions for foundation isolation as well as for material testing machines including tensile, compression and fatigue testing equipment that can create vibration and shock.

 

Aerospace Testing

 

When performing testing of large spacecraft or hardware that will be launched into orbit, it is necessary to conduct testing in a space-simulated environment. To achieve this, a vacuum chamber or thermal vacuum chamber is used which creates an environment to simulate the pressure and thermal effects of launch or space travel in orbit.

 

It is necessary to decouple the spacecraft or payload from the chamber using Fabreeka vibration isolators to attenuate environmental vibration from the testing. In some cases, where feasible, the entire chamber with payload is decoupled from the test facility. In cases where the size of the vacuum chamber, or the existing chamber, does not allow for external isolators the test payload must be isolated inside the chamber. To achieve this, a vacuum compatible isolation system is used. When isolators are used inside a vacuum chamber, they must meet strict material specifications to limit out-gassing and be constructed to fulfill particulate and molecular cleanliness requirements as well. Additionally, in thermo-vacuum applications, the isolators may be required to function in temperature extremes where heater blankets are necessary to keep them at an operable temperature.

 

Applications often include nano-type measurements and can have error budgets within microns or tenths of arc seconds. In this sensitive field, experts cooperate with Fabreeka and use customized stainless steel PAL isolators for vacuum chamber isolation with a special design to keep air permeation to a minimum so the vacuum chamber can achieve deep vacuum levels. The assembly can be done in a clean-room environment, and isolator components can be baked out to minimize out-gassing.

 

Aircraft Testing

 

Fabreeka has designed a number of soft support systems (SSS) using standard and custom pneumatic isolators for ground vibration testing (GVT) of aircraft. To obtain accurate results during GVT, the modal testing of the aircraft requires simulation of a “free-free” condition. To achieve this condition, Fabreeka works with the structural and dynamics testing groups of aircraft manufacturers to design the required SSS for the GVT.

 

The pneumatic isolators support and decouple the aircraft from the ground when the aircraft is undergoing GVT and modal or flutter analysis. The role of the system is especially important in identifying structural resonances and validating flutter models. The SSS can include a mechanical jacking system to lift the aircraft off of its landing gear. Fabreeka’s custom isolator designs can achieve a natural frequency as low as 0.5 Hz.

 

Professionals are well aware that they save time during testing by using a Fabreeka custom system since traditional methods such as bungee cords are very time consuming due to the bungees being changed out for every load condition.

 

Auto Testing

 

Fabreeka is also a leader in providing vibration isolation systems and design techniques to meet the growing demands of vehicle testing in simulated environments where dynamometers, engine test rigs, road simulators and multi-axis shaker tables are in use. Here, Fabreeka’s technical expertise includes the structural design of support structures and reaction masses; static and dynamic analysis and acceptance testing.

 

In many cases when the forces are not extreme and the frame or base of the machine is rigid, Fabreeka's PAL or RLA pneumatic isolators are directly placed under the equipment, namely dynamometers or vibration tables. RLA isolators offer a larger piston stroke to handle larger dynamic loads typically seen in vibration testing applications such as shakers and 4-post-shakers without compromising the natural frequency of the system.

 

PAL or RLA pneumatic isolators are also the right choice for supporting a concrete foundation with the test equipment. Over decades, Fabreeka has gained the expertise to develop all types of vibration isolation projects for automotive testing and can provide a turnkey solution including foundation design, demolition, construction work, bedplate, installation and acceptance testing.

 

Countless successful projects with car and truck manufacturers are also proof of Fabreeka's know-how from concept to the final production model in rolling road isolation.

KEY FEATURES/BENEFITS

  • Natural frequencies from 0.6 Hz, depending on design
  • Virtually constant load-independent vertical natural frequency over a wide load range
  • Can support payloads from 7,700 to 69,300 lbs per isolator
  • Large usable stroke range
  • Resistant to most oils, alkaline or acidic cleaning agents, dust, dirt, ozone, UV radiation, general weathering

Air spring isolators are another part of Fabreeka’s portfolio. Bellows cylinder air springs, also known as rolling lobe isolators or airbag isolators, provide low frequency vibration isolation for applications requiring high dynamic vibration amplitudes and lifting heights.

 

Rubber air springs may have vertical and horizontal natural frequencies from 0.6 Hz, depending on operating height, and belted bellows cylinder design (single, double or pneumatic air bellows). Horizontal spring rate, that is the stiffness of the system, and stability also depend on operating height, so each air cushion type has an ideal operating height.

 

Lower vertical natural frequencies are achievable by increasing air volume, for example with an auxiliary tank. A large usable stroke range is a key feature in Fabreeka’s belted bellows air spring isolators (RLA), with stroke ranges from 2” to 3” possible depending on bellow design – ideal for applications prone to large dynamic deflections.

 

Fabreeka as complete system provider

 

A complete isolation system consists of at least three controlled bellows cylinder air springs for three-point level control. Each air spring isolator made by Fabreeka has an integrated level control valve that functions as a load and position sensor. If larger loads should be carried by the construction, any number of additional air springs can be added. Moreover, when working with Fabreeka, each system comes with a control panel, automatic height control valves, pneumatic tubing and all of the pneumatic accessories necessary for complete system installation.

FAQS

What is the leveling accuracy of the PAL isolators?
The leveling accuracy of the PAL isolators depends on the type of valves used. The standard FLV-4 valve has an accuracy of +/-0.005″, while the optional FLV-7 valve has an accuracy of +/-0.001″.

 

What are the vertical and horizontal damping values for PAL isolators?
The vertical damping value of a PAL isolator is adjustable by 6-20% on all standard sizes, while the horizontal damping is 3-6% depending on the isolator type.

 

Will you explain transmissibility/percent isolation?
The transmissibility of an isolator is a relative measure given as a ratio of output amplitude to input amplitude. The lower this ratio, the greater isolation an isolator provides.

 

Which leveling valve is recommended for my application?
The standard PAL isolators use the FLV-4 valve, which is suitable for most applications. If the isolated mass has a distance between isolators less than three times the vertical center of gravity, is supported by only three isolators or a large moving mass, a FLV-7 valve may be necessary. Large systems may require higher flow valves. Please contact Fabreeka’s Engineering department at 1-800-322-7352 or info@fabreeka.com to discuss your specific application.

 

What size PAL isolators should I use for my application?
PAL isolators are sized based on the total supported mass and the number of isolators used. All isolators have a maximum load capacity at 100 psi, which should not be exceeded. All isolators should have a working pressure within 15 psi of each other for stability.

 

What type of tubing should be used to connect to my air supply?
All tubing and fittings used for our pneumatic systems should be rated for a minimum of 120 psi working pressure. 1/4″ OD tubing is a minimum recommendation. Tubing and fittings are supplied with our systems.

 

What are the major design parameters/calculations when choosing pneumatic isolators to isolate my equipment?
In order to select a pneumatic isolation system, the following information is necessary:

  • Isolator frequency and damping required for isolating equipment (may require a vibration survey)
  • Total weight of isolated mass
  • Number of isolators, based on geometry
  • Center of gravity of isolated mass
  • Any moving mass on equipment

What is the air consumption of a PAL system?
The air consumption is determined by the valves used in the system. The maximum consumption is 16 scfm at 100 psi during the initial filling, but if less is available, it will simply take longer to fill the isolators. During normal operation, the system will consume zero to 4 scfm, depending on how much the isolated mass moves.