Tag Archives: Vibratory Tubs

Mass Finishing Machine Settings Series, Part 2 – Determine Imbalance Weight Settings for Consistent Results

Specific mass finishing applications are developed through processing trials. Once defined, users should not deviate from the determined machine settings unless necessitated by work piece or process changes.

Rosler partners with clients to provide testing in our global Customer Experience Centers to demonstrate our capabilities on a specific work piece and to calibrate machine settings. Determining the exact machine settings requires considering and testing multiple factors.

Vibratory Systems

The most common drive systems in mass finishing are vibratory. This refers to actual finishing machines such as rotary, tub, and linear continuous flow vibrators as well as auxiliary equipment like screening systems, vibratory conveyors, buffers, etc.

In all of these cases, the speed of the vibratory motor or the electric motor driving the imbalance unit(s) may have to be adjusted as well as the setting of the imbalance weights.

Vibratory weight plates

The angle between the upper and lower imbalance weights determines the movement of the media and work piece mix within the machine.

The number (mass) of imbalance weights determines the processing intensity (amplitude). More weights produce higher intensity while fewer weights deliver lower intensity.

Cutaway diagram detailing vibratory motor parts including upper and lower imbalance weights and the electric motor
Vibratory motor diagram

Setting Imbalance Weights

The movement of the media/work piece mix is always opposite to the motor direction. Typically, the motor runs clockwise and the media/work piece mix runs counter clockwise.

In some instances, the motor can run clockwise and counterclockwise including the Rosler “R” machines and gate clearing in Rosler “Euro” machines.

Half-circle metal plate weights on the top and bottom of the motor must be positioned with respect to each other. For a basic setting, the bottom weight plate must be turned 90 degrees forward of the top weight plate, in a basic setting.

Imbalance weights locations and settings within a vibratory motor
Imbalance weights locations and settings within a vibratory motor

When setting imbalance weights, it is important to understand the impact of changes. For example, increasing the lead angle will make the media/work piece mix travel around the work bowl faster. Decreasing the lead angle will have the opposite effect, slowing movement.

Typical lead angles range from 70 to 120° and can be observed by checking the gauge on the top of the motor shaft.

image showing vibratory motor lead angle gauge
Vibratory motor lead angle gauge

Within the imbalance weights, the top weight controls the travel speed of the media/work piece mix around the work bowl. Adding additional weights to the top will increase the travel speed while decreasing the spiral speed in the work bowl.

The top imbalance weight controls media and workpiece speed around the work bowl as represented by the red arrow while the bottom imbalance weight controls the spiraling speed of the work bowl contents.
The top imbalance weight controls media and workpiece speed around the work bowl as represented by the red arrow while the bottom imbalance weight controls the spiraling speed of the work bowl contents.

The bottom weight controls the spiral speed of the media/work piece mix in the work bowl. Conversely to the top weight, adding additional weights to the bottom will increase the spiral speed but also decrease the travel speed around the work bowl.

Action Points

Regularly checking a mass finishing machine’s settings including motor speed(s), setting of imbalance weights, work station angles, etc. to ensure they are as initially established will produce better results and protect the systems ROI.

A vibrocope sticker on the work bowl allows for a quick check of the processing intensity. Additional information can be found in our Using Vibrascope to Measure Amplitude v. Frequency in Vibratory Bowls blog post.

photo of a vibroscope sticker
Virboscope sticker

Additionally, if repairs require drive motors to be disconnected, make sure that they are rewired correctly and are not running in the wrong direction.

If the machine settings must be changed, carefully follow the instructions in your operator’s manual or consult the manufacturer for assistance.

If not already integrated, installation of a frequency inverter for precise setting of the drive speed of your machine may be available as an upgrade, providing additional control and oversight.

The Rosler Way

Rosler goes beyond developing mass finishing machines to provide operational insight and guidance for the lifetime of our machines as well as consumables and service. Contact us to discuss your needs and our capabilities.

The Mass Finishing Machine Settings Series also includes Part 1 – Improve Machine Function with Proactive and Responsive Observation, Calibration.

Monitor Wear Linings to Maintain Process Efficiency, Increase Equipment Longevity

Mass finishing machinery is a major investment for most companies. Proper maintenance and preventative repairs over the life of these useful and necessary machines will greatly improve the return on such investments, drive productivity, and extend the working life of the equipment itself.

Rosler stresses the need to regularly inspect the linings of vibratory tubs and troughs to identify repairable issues before permanent damage occurs.

Media-Induced Wear

To effectively finish work pieces, media must be matched to the specific finishing task and initial state of a work piece. For example, media used for deburring/edge radiusing and surface grinding can be very abrasive. If not properly protected by a suitable wear lining, the steel construction of a work bowl would be completely worn through in a few hours by contact with the media and work pieces.

Continue reading Monitor Wear Linings to Maintain Process Efficiency, Increase Equipment Longevity

Automotive Crankshafts, Part 3 – Typical Mass Finishing Machines Used for Crankshafts

Crankshafts are an integral automotive component. Utilized to convert piston movement into rotational motion, these work pieces must provide reliable stability and withstand tensile, compressive, and shear stresses.

Rosler Metal Finishing has extensive experience finishing crankshafts and other automotive work pieces with specially designed shot blasting and mass finishing equipment.

Let’s take a closer look at mass finishing machines offering outstanding processing for crankshafts.

Typical Machines

Built with specific work pieces in mind, Rosler designs several machines to process crankshafts and other automotive work pieces.

Due to their considerable size and weight, the only mass finishing machines capable of handling the deburring of crankshafts after machining are mid- to large-sized tub vibrators or linear, continuous flow vibrators.

Selecting one machine type over the other largely depends on the work piece’s size.

Continue reading Automotive Crankshafts, Part 3 – Typical Mass Finishing Machines Used for Crankshafts

Aerospace, Part 1 – Cost-Effective, Mechanical Finishing for Large, Structural Aircraft Components

To this day, the surface of large structural aircraft components is frequently finished by hand. This process is not only costly, but extremely inefficient and hard to replicate with absolute conformity.

Airplane Landing Gear

Rosler Metal Finishing is changing the notion that suitable mechanical finishing equipment is not available for large, structural aerospace components by offering mass finishing technology capable of solving this problem and providing fully automatic finishing of work pieces up to 30 feet long.

We kick off our Aerospace Series with an overview of the cost-effective and mechanical finishing options Rosler offers for the Aerospace industry.

Vibratory Tubs Offer a Solution

Thanks to the development of large, powerful vibratory tubs manual deburring and grinding of large aircraft components can now be eliminated. The development of perfectly controlled mechanical finishing systems offers finishing solutions for applications where the biggest rotary vibrator, because of the size of the parts, might still be too small.

Continue reading Aerospace, Part 1 – Cost-Effective, Mechanical Finishing for Large, Structural Aircraft Components

Using Vibrascope to Measure Amplitude v. Frequency in Vibratory Bowls

When it comes to mass finishing, amplitude and frequency require balance and careful consideration.  Amplitude is a measure of movement and intensity while frequency refers to the rate of repetition.

The wrong amplitude, for example, if  it’s too low, can create a lackluster finishing results and longer processing times. If too high it can cause unnecessary wear and tear on the machine.

Creating Vibratory Energy

Whether rotary or tub style, mass finishing vibrators always include these two key components; a work bowl containing the finishing media and the work pieces. Firmly attached to this work bowl is a vibratory drive system generating the energy to put the mass of media and work pieces in motion. The work bowl with attached vibratory drive system sits on a number of coil springs – in some cases on air cushions – which in turn sit on a machine base. The springs, respectively, air cushions allow the work bowl to “free float” up and down within a certain distance.

vibratory drive
Example of vibratory drive 

The force from the vibratory drive system puts the mass of finishing media and work pieces contained in the work bowl in motion. Depending on the type of finishing machine this force is generated by vibratory motors or electric motors driving a shaft with one or multiple imbalance units attached to it.

Imbalance units are made up of a rotating shaft with out-of-balance counterweights at each end of the shaft. Due to its imbalance, the rotating shaft causes an intensive wobbling effect.

Common drive systems in vibratory bowls and tubs include foot motors for small tub vibrators, flange motors for rotary vibrators, and multiple imbalance units with electric drives for large tub vibrators.

Continue reading Using Vibrascope to Measure Amplitude v. Frequency in Vibratory Bowls

Part 2 – Aerospace Applications for Vibratory Finishing

Vibratory tub finishing is a great alternative to manual surface finishing for the aerospace industry.

From engine components and wings to landing gear, properly designed vibratory tubs can accommodate unwieldy work pieces, reduce production times and back logs, and produce a more consistent finish than manual finishing processes.

Our last blog post provided an overview of vibratory finishing’s role in the aerospace industry.

We now turn to specific applications and machine reports to demonstrate Rosler Metal Finishing’s vibratory finishing offerings and capabilities.

What We Offer

Vibratory tub finishing machines from Rosler can be customized to meet your unique aerospace finishing challenges.

Our most useful features include:machine2

  • Unload gates with external screening units.
  • Automatic media return.
  • Integrated rinse stations for finished work pieces.
  • Gantry systems for easy material handling of heavy, bulky parts.
  • Ergonomic equipment designs.

All Rosler tub vibrators are equipped with special vibration dampers to prevent the transfer of vibrations to the immediate environment. In order to keep the noise level below 80 dB(A), the machines are placed in special noise
protection cabins.

Continue reading Part 2 – Aerospace Applications for Vibratory Finishing

Part 1 – Vibratory Finishing Replaces Manual Finishing in Aerospace Industry

The aerospace industry  demands precision and high quality. The processes used to finish aerospace work pieces should adhere to the same rigorous demands.

Gone are the days when the surface of large structural aircraft components is frequently finished by hand. Thanks to the development of large, powerful vibratory tubs, costly manual deburring and grinding of large aircraft components can now be eliminated by highly controlled mass l finishing systems.

Finding A Better Way

Manual deburring and grinding are tedious and costly. Attempting these types of mass finishing by hand usually causes large quality fluctuations with relatively high scrap rates. Above all, manual processes demand highly skilled labor, which is especially hard to find in today’s economy and tight labor markets.

The lack of skilled labor and manual inefficiencies can lead to severe bottle necks in production and long lead times.

Continue reading Part 1 – Vibratory Finishing Replaces Manual Finishing in Aerospace Industry