A production halt due to a broken roller or bushing is a classic scenario that results in lost time and money. Parts made from traditional rubber or steel often fail to withstand impacts, abrasion, or repetitive loads, leading to frequent replacements. Polyurethane significantly extends the service life of components and reduces unscheduled downtimes. This article explores the strength of polyurethane parts, how to select the right material for the task, and why TIMOL produces parts that truly last longer.
How Does Polyurethane Ensure High Strength and Load Resistance?
Polyurethane, with its combination of elasticity and high tensile strength (25-60 MPa), can simultaneously absorb impacts and withstand prolonged static and cyclic loads. This enables parts to maintain their shape and functionality even in high-dynamic assemblies, such as conveyor rollers, guides, bushings, or screens. Unlike rigid plastics, polyurethane products do not crack or crumble under repeated impacts or bends.
In the mining and metallurgical industries, polyurethane scrapers, bushings, and linings encounter large masses of material moving at high speed. In such conditions, it is crucial that the part not only withstands the load’s weight but also dampens impacts and vibrations. Polyurethane effectively absorbs these loads, maintaining the assembly’s geometry and protecting the equipment’s body from transmitted impulses.
A wide range of hardness (from 50 Shore A to 70 Shore D) allows for optimizing properties for specific tasks: from elastic seals to structural supports and bearing elements. This versatility makes polyurethane applicable in 12 key industries, from mechanical engineering to the food industry.
Strength and Wear Resistance Comparison: Polyurethane vs. Rubber, Steel, Plastics
In industrial assemblies, polyurethane excels due to its unique balance of properties: abrasion resistance, impact strength, elasticity, and stability across a wide temperature range. For decision-making, chief engineers need precise numbers, not general terms. Below is a comparison table for key assembly materials:
| Material | Abrasion DIN 53516, mm³ | Tensile Strength, MPa | Hardness | Working t, °C |
|---|---|---|---|---|
| Polyurethane (TIMOL) | 20-45 | 25-60 | 50A - 70D | -60…+100 |
| SBR Rubber | 100-200 | 8-20 | 40A - 80A | -40…80 |
| NBR Rubber | 80-150 | 10-25 | 40A - 90A | -30…100 |
| Natural Rubber (NR) | 60-130 | 20-30 | 30A - 80A | -50…70 |
| Caprolon (PA6/PA66) | 30-90 | 60-85 | 75D - 85D | -40…100 |
| Carbon Steel | , | 370-700 | 120-250 HB | -40…500 |
| Wear-resistant Steel Hardox | , | 1250-1600 | 370-540 HB | -40…250 |
Polyurethane (20-45 mm³) outperforms caprolon (30-90 mm³) by 2-5 times and SBR rubber (100-200 mm³) by 5-10 times in wear resistance. Its tensile strength (25-60 MPa) surpasses all types of rubber and is only slightly lower than caprolon (60-85 MPa) and steels, while retaining elasticity (rebound resilience 35-65%), which rigid plastics lack.
The key advantage is that polyurethane is not only strong but also elastic: it absorbs impacts, cushions abrasives, and does not transmit vibrations to the machine body. This significantly extends the component’s lifespan, reduces noise levels, and lessens the load on other structural components. In products like wheels, rollers, bands, or linings, this is critical for stable equipment operation.
How to Choose the Right Polyurethane Hardness for Loaded Assemblies?
Selecting the hardness of polyurethane determines not only the service life but also the behavior of the assembly under real conditions. For parts with abrasive or impact loads (screens, linings, scrapers), the optimal hardness is 80-95 Shore A: this is the upper limit of a still elastic material that absorbs impacts and repels abrasives, preventing them from cutting the surface. For seals, gaskets, and o-rings, 70-90 Shore A combines sealing with load resistance.
Parts that bear constant high pressure or must maintain precise shape (such as plates, supports, guides) are made in the range of 60-70 Shore D. Here, geometric stability is key, not impact absorption. It’s important not to confuse: Shore D hardness is not suitable for abrasive wear, as elasticity is lost and the risk of chipping increases.
TIMOL manufactures cast polyurethane products according to customer drawings, considering not only the type of assembly but also the nature of the loads: axial, radial, combined, taking into account temperature and working environment. This allows achieving maximum resource and reliability of the assembly.
Engineer Tip: The hardness of polyurethane critically affects the service life of the assembly. For parts working under abrasion or impact, choose hardness at the upper Shore A limit, ensuring elasticity and cushioning, minimizing chips and cracks. Do not chase maximum rigidity: Shore D is suitable only for stable, load-bearing products.
Polyurethane Behavior Under Static, Dynamic, and Impact Loads
Polyurethane parts demonstrate resistance to all major types of loads. Under static loads, such as in rollers or supports, polyurethane does not exhibit residual deformation, maintaining size and shape even after prolonged pressure. This is crucial in assemblies where fit accuracy determines machine reliability.
Under dynamic and cyclic loads, typical for conveyor systems, transport rollers, bands, and screens, polyurethane retains integrity, does not crack or delaminate even after hundreds of thousands of work cycles. In concrete mixer linings and scrapers, the material absorbs impacts and vibrations, not transmitting them to the metal body. This reduces fatigue failure and noise.
In particularly challenging conditions, with impacts from large material fractions or foreign objects, polyurethane does not crumble or chip but absorbs the impulse, returning to its original shape. No other elastomer or rigid plastic provides such behavior. Therefore, polyurethane is advantageous for use in gravity equipment, hydrocyclones, scrapers, and guides in mining and metallurgical assemblies.
Where Does Polyurethane Truly Outperform Steel, Rubber, and Plastic in Assembly Reliability?
Assemblies subjected to a combination of abrasion, impact, vibration, and deformation are often weak points in traditional materials. Rubber wears quickly (100-200 mm³ per DIN 53516 for SBR), steel corrodes, transmits impacts and vibrations to the structure, and caprolon is brittle under sudden impacts. Polyurethane demonstrates a lifespan 10 times greater than rubber, resists corrosion, retains properties at low temperatures, and does not crack under impacts.
In mining, metallurgical, transport, and pipe rolling lines, polyurethane buckets, guides, screens, scrapers, and plates truly last longer, reducing maintenance and repair costs. For gravity equipment and linings, polyurethane provides not only service life but also operational stability, with assemblies requiring less frequent inspection and replacement.
In light industry and food sectors, polyurethane also excels due to its chemical resistance and lack of product contamination. In rollers and bands, polyurethane ensures smooth operation, lower noise levels, and less load on equipment bearings.
Custom Manufacturing of Polyurethane Parts and Installation Features
TIMOL operates using free casting technology, allowing the production of parts of any complexity, from simple bushings to complex geometries of screens and scrapers. Each part is cast in a mold, ensuring precise dimension reproduction and uniform hardness distribution throughout the product mass. For abrasive and impact assemblies, the choice of hardness, layer thickness, and fastening scheme is agreed upon individually with the customer.
Installation of polyurethane parts is carried out using standard methods: through flanges, bolts, press fits, adhesive or mechanical connections. For linings, it is important to properly prepare the surface for adhesion, ensuring fastening strength and long service life. All products are marked for further identification and service.
TIMOL engineers assist in selecting material, hardness, thickness, and type of installation for each assembly, from screen to roller band. To familiarize yourself with the factory’s products, view the catalog of polyurethane products and study the reference information on polyurethane.
Temperature Stability and Operation in Various Conditions
TIMOL polyurethane reliably operates in a range from -60 to +100 °C, sufficient for most industrial processes. The material does not harden in the cold, does not become brittle with sudden temperature changes, and does not soften when working with hot flows. This allows the use of polyurethane bushings, rollers, linings, and seals in railway transport, pipe rolling production, mining equipment, and food lines.
If the assembly operates outdoors or experiences short-term overheating, polyurethane retains its properties and shape, not degrading under UV or moisture exposure. Compared to rubber, which ages quickly in the sun or at low temperatures, polyurethane demonstrates stable performance regardless of season and external conditions.
Conclusion: When to Choose Polyurethane and How to Order a Part
Polyurethane is the optimal choice for assemblies requiring high wear resistance, tensile strength, impact damping, and a wide temperature range. In 12 industrial sectors, polyurethane parts overcome the shortcomings of rubber, steel, and plastics, ensuring stable operation of assemblies without unnecessary downtimes. For resource calculation, hardness selection, and custom part manufacturing, contact TIMOL engineers via contacts or leave a request on the website. Engineering support, individual material selection, and quality execution guarantee a long service life for your equipment.