Mining machinery damping should start with a defined mechanical task: limit transmitted vibration, control impact, or maintain component position within an allowable movement envelope. These tasks can require different stiffness, damping and geometry. A polyurethane block selected only by hardness may fit the drawing while failing to deliver the required behavior in the machine.
For equipment designers, the objective is to protect the intended load path while preserving the machine’s working motion. This guide explains the inputs to specify, the tradeoffs to review and the evidence to request before approving a custom cast polyurethane component.
Mining Machinery Damping: Define the Function Before Choosing a Part
| Function | Design objective | What to measure |
|---|---|---|
| Vibration isolation | Reduce vibration transmitted between an assembly and its support. | Response at defined locations and frequencies, together with assembly movement. |
| Energy dissipation | Control oscillation or rebound by dissipating mechanical energy. | Dynamic response, recovery and temperature rise under representative cycling. |
| Impact buffering | Manage a transient event within the available stopping distance. | Peak reaction, displacement, rebound and damage. |
| Positioning and support | Maintain alignment and clearance under static and changing loads. | Load–deflection behavior, residual deformation and retention. |
A component may serve more than one function, but the requirements should be stated separately. A vibrating screen needs intentional working motion; reducing that motion indiscriminately can change its process performance. An end-stop buffer, by contrast, must control a defined impact within a limited stroke.
For examples of component locations across the process, see our mining and mineral-processing applications.
Why more damping is not always better isolation
Stiffness determines how much force is required for deformation. Damping describes energy dissipation. They are related through the component’s behavior, but they are not the same property.
In a simplified mounting system, increasing damping can control resonance while reducing isolation effectiveness in another frequency region. Select against the excitation frequencies and movement limits, rather than maximizing damping alone. Parker LORD’s industrial isolation engineering guide explains this tradeoff.
Real mining assemblies can have several vibration modes, impacts and changing payloads. A single material property or simplified model is a screening tool, not approval of the complete installation.
What Should Be Included in the Design Specification?
Describe the load at the proposed component, not only the total machine mass. Unequal support loading, center-of-gravity offsets and forces in multiple directions can change what each part experiences.
| Input | Information to provide | Design implication |
|---|---|---|
| Load case | Static load per support, peak events, load direction and payload variation. | Support area, strain, retention and overload behavior. |
| Excitation | Operating frequency range, impact sequence, startup and shutdown conditions. | Dynamic stiffness, resonance review and cycling requirements. |
| Movement | Installed compression, working displacement, maximum travel and alignment limits. | Geometry, clearances and hard-contact risk. |
| Duty cycle | Run time, pauses, cycling frequency and recovery periods. | Fatigue, heat buildup and long-term deformation. |
| Environment | Part temperature, oil, water, slurry, dust and cleaning exposure. | Formulation screening and combined-exposure testing. |
| Interface | Mounting surfaces, core or inserts, fasteners and bonding requirements. | Local loading, assembly variation and serviceability. |
| Acceptance | Allowed movement, transmitted response, reaction force and replacement trigger. | A measurable decision on prototype suitability. |
Include drawings and an explanation of what the current part does wrong. For dimensional and manufacturing considerations, use our custom polyurethane component design guide alongside the application specification.
Selecting Polyurethane: Review the Material and Geometry Together
Hardness is a starting point, not a damping specification
Two cast polyurethane formulations at the same Shore hardness can have different dynamic response, recovery, tear behavior and resistance to the operating medium. Ask for data relevant to the proposed loading and temperature, rather than assuming that a hardness match creates an equivalent replacement.
Compare candidate materials through a cast polyurethane material selection guide, then define the component-level test. A polyurethane formulation should also be compared with suitable alternatives when its property balance does not meet the required function.
Shape, confinement and mounting change the response
Area, thickness, free surfaces and lateral constraint all affect the behavior of an elastomer block. Changing one dimension to fit the available space can change force–deflection response. Account for installed compression, edge loading and any limit on bulging.
- Provide controlled travel: check clearance at the most demanding displacement and tolerance combination.
- Avoid concentrated strain: review sharp transitions, unsupported edges and uneven contact.
- Design the interface: evaluate bonding or mechanical retention separately from bulk material strength.
- Plan replacement: make wear limits, orientation and access clear to service teams.
Temperature and media belong in the dynamic review
Evaluate the temperature of the part during repeated deformation, not just ambient air. A design that works briefly may behave differently after sustained cycling. Equally, a cold start can produce a different response from warmed-up operation.
Use the polyurethane temperature-range guide to frame the exposure profile. For winter equipment, review polyurethane in cold climates and include cold-conditioned startup behavior in validation.
Three Application Examples for Equipment Designers
These examples illustrate design decisions. They do not report verified customer outcomes, a universal material grade or a guaranteed reduction in vibration.
1. Hydraulic Breaker Support Blocks: Control Movement Without Losing Position
Design task: support and guide the breaker body inside its housing while accommodating the intended movement and repeated loading.
Tradeoff: a support that allows excessive travel can permit unwanted contact or misalignment. A support that is too stiff for the intended arrangement can alter transmitted loads. Top support and lateral guidance should be evaluated for their separate duties, rather than assigned the same hardness automatically.
Review: installed compression, force direction, clearances, edge support, oil exposure and heat generated during the operating cycle.
Validate: measure relative movement and selected housing or bracket responses during a defined test. Inspect permanent deformation, edge damage and retention. Confirm breaker performance under comparable duty so a reduction in one measured response is not achieved by restricting its intended operation.
Image interpretation: a housing cutaway should show where the body is supported, where it is guided and how much movement is allowed. This explains the component’s role more clearly than a mining-site photograph.
2. Vibrating Screen Supports: Preserve Working Motion and Limit Frame Response
Design task: allow the screen body to perform its intended motion while managing vibration transmitted into the supporting frame.
Tradeoff: changing a support changes the dynamic system. Do not treat a polyurethane pad as a direct substitute for an existing coil spring or mount based only on size and load capacity.
Review: loaded and unloaded mass, support reactions, excitation range, motion direction, startup and shutdown response, movement clearance and material discharge requirements. A PU support is a candidate only where its dynamic behavior meets the system requirements.
Validate: measure the screen-body motion and frame response at defined locations under representative feed conditions. Check processing performance, clearances, temperature and support durability. A quieter frame alone does not prove that screening performance has been preserved.
Image interpretation: show the screen body, elastic supports and base frame together, with separate arrows for working motion and transmitted response. A screen-panel close-up would illustrate a different component.
3. Hopper or Chute End-Stop Buffer: Manage Impact Within a Fixed Stroke
Design task: cushion a moving assembly as it approaches a mechanical travel limit.
Tradeoff: too little usable stroke can produce a high reaction or hard contact; an unsuitable recovery response can create excessive rebound. The buffer must be assessed together with its supporting structure.
Review: moving mass, approach speed, available stroke, drive force during contact, event frequency, alignment and the allowed reaction. Include gravity or actuator work where relevant; moving mass alone does not define the complete event.
Validate: reproduce the specified contact sequence and measure reaction and travel. Check rebound, temperature, residual deformation and damage over the required number of events. Set an inspection or replacement limit that maintenance staff can apply.
Image interpretation: use a side view showing available compression travel and the mounting plate. Do not add numerical stress colors or deceleration curves unless they come from a documented analysis or test.
How to Validate a Mining Damper Prototype
- Define the comparison: identify the current or reference assembly, duty cycle, payload and installation conditions.
- Measure the required function: record displacement and reaction for impact duties, or frequency-dependent response at selected points for isolation duties.
- Include operating variation: evaluate startup, shutdown, payload changes and credible transient conditions.
- Track durability: inspect wear, cracking, permanent deformation, interface condition and changes in response during representative cycling.
- Confirm production requirements: document the approved material, geometry, processing, inspection and acceptance criteria.
Use consistent sensor locations, directions and operating conditions when comparing versions. State whether a result concerns force, acceleration, displacement or sound. An acceleration reduction at one point is not automatically the same reduction in transmitted force, airborne noise or operator exposure.
For sourcing decisions, compare cost against an agreed component function and replacement criterion. An unsupported claim of longer life is less useful than a reproducible test and a clear inspection limit.
Frequently Asked Questions
What hardness should a mining damper use?
There is no universal hardness. Specify the load, allowed movement, duty cycle and environment, then compare formulation and geometry together through relevant component tests.
Can polyurethane replace a rubber mount or steel spring?
It may be a candidate, but it is not a direct equivalent based on external dimensions. Recheck dynamic response, alignment, interfaces, temperature and the machine’s intended motion before approving the change.
What is the difference between a damper and an impact buffer?
The names are sometimes used loosely. Specify the duty: managing repeated oscillation, isolating vibration, supporting position or limiting an impact. The required evidence follows the duty, not the product name.
Will a softer part always reduce vibration?
No. It may increase movement or change resonance and alignment. Review the complete operating range and permissible travel.
How should an OEM demonstrate improved performance?
Define the response being improved, use comparable operating conditions and verify that the machine’s working function is preserved. Report measured results with their test conditions and limits.
Discuss Your Mining Machinery Damping Requirements
Kubis Tech manufactures custom cast polyurethane components. To discuss a proposed design, send the drawing, load cases, frequency or impact sequence, available travel, temperatures and the acceptance target.
Browse our custom polyurethane vibration dampers for component examples. Product form alone does not establish suitability for your operating conditions.
Send your drawing and damping requirements to Kubis Tech to discuss material screening, manufacturability and prototype validation.
