---
title: "Polyurethane Hardness on the Shore Scale: How to Choose the Right One for Your Unit"
description: "Learn how to choose polyurethane hardness on the Shore scale for industrial units. Comparison with rubber and plastic, tips from a TIMOL factory engineer."
lang: "en"
date: "2026-08-09"
canonical_url: "https://timol.com.ua/en/statti/tverdist-poliuretanu-shore"
---
# Polyurethane Hardness on the Shore Scale: How to Choose the Right One for Your Unit

Have you ever faced a situation where a scraper or seal wears out after just a month of use, and the downtime costs more than the part itself? Or a steel lining that only lasts a season due to impact wear? Polyurethane allows for precise hardness selection for a unit, from flexible seals to rigid structural elements, providing a lifespan 10 times greater than rubber. In this article, we explore how to determine and choose the right polyurethane hardness on the Shore scale for a specific task, ensuring the unit operates longer without replacement.

## What is Shore Hardness and How is it Determined

Shore hardness is a key parameter that defines how well polyurethane resists penetration or deformation under load. Hardness is measured using a durometer: the Shore A scale is used for elastomers (soft to medium hardness), and the Shore D scale for rigid polymers. The device presses an indenter against the sample, and the scale shows the result in 'Shore' units.

For TIMOL polyurethane, the working range is **from 50 Shore A to 70 Shore D**. This range covers needs from cushioning elements to rigid parts that operate under high pressure. For example, seals and gaskets are often made with a hardness of **70-90 Shore A**, scrapers, linings, and screens, **80-95 Shore A**. For rollers, bands, and bushings, where shape stability under load is required, the upper limit, **Shore D**, is used.

Hardness not only affects the feel of the material but also its behavior in the unit: how much it deforms under static or dynamic load, whether it will absorb shocks or transfer them to the metal structure.

## How to Choose Polyurethane Hardness for a Unit and Load

The selection of polyurethane hardness depends on the type of load, wear characteristics, temperature, and working environment. It's important to understand that there is no universal value for all units; the optimum varies for each task. For abrasive and wear-resistant parts (screens, linings, scrapers), the optimal hardness is **80-95 Shore A**. This provides elasticity and the ability to absorb impact, preventing material cutting or chipping.

For example, in the mining industry, crusher or chute linings endure constant impacts from ore or coal. Using polyurethane of 90-95 Shore A acts as an elastic buffer, causing particles to bounce off rather than cut into the material, significantly slowing wear. For seals, gaskets, and packings (e.g., in pipe manufacturing or oil and gas), **70-90 Shore A** is chosen: the material is dense enough to press against the shaft but not brittle or quick to wear.

For structural, load-bearing parts like rollers, bands, and bushings, where dimensional stability is key, **Shore D** is selected. Determining the optimum involves analyzing working conditions (temperature, type of load, contact with the environment) and consulting with TIMOL factory engineers.

> Practical tip: For linings and wear-resistant plates in the mining or metallurgical industry, polyurethane of 90-95 Shore A works best. It elastically absorbs abrasive impact, doesn't crack, and lasts longer than rigid plastics or steel.

## Why Choose Shore A, Not Shore D for Abrasive and Wear-Resistant Parts

For working with abrasives, it is crucial to choose the upper range of **Shore A (80-95)** rather than switching to Shore D. Polyurethane's abrasion resistance is based on elasticity: the material prevents abrasive particles from cutting grooves and literally repels them. If too hard a polyurethane (Shore D) is chosen, it loses elasticity and begins to chip or crack under impact.

This is critical for conveyor belt scrapers, vibrating screens, and linings in industries where abrasives are constantly present, such as mining, metallurgy, and agriculture. Practice shows that polyurethane of 90-95 Shore A provides the best balance between wear resistance and elasticity, whereas rigid plastics (e.g., caprolon) quickly chip in such conditions.

Seals and gaskets are also made within the range of 70-90 Shore A: if a softer material is chosen, leakage will occur, while a harder one won't withstand dynamic loads. For structural units where there is no abrasive and geometric stability is needed, Shore D is used.

## Comparative Table of Hardness and Wear Resistance (DIN 53516)

| Material | Hardness (Shore) | Abrasion, DIN 53516 (mm³) |
|----------------------------------|--------------------|---------------------------|
| Polyurethane (TIMOL) | 50A - 70D | 20-45 |
| NBR Rubber | 40A - 90A | 80-150 |
| SBR Rubber | 40A - 80A | 100-200 |
| EPDM Rubber | 30A - 90A | 80-180 |
| Natural Rubber | 30A - 80A | 60-130 |
| Caprolon (PA6/66) | 75D - 85D | 30-90 |
| UHMW-PE | 60D - 70D | 15-30 |
| PTFE | 50D - 65D | 200-500 |

It is clear: TIMOL polyurethane has an abrasion level according to DIN 53516 of **20-45 mm³**, while rubber shows **80-200 mm³**. This demonstrates a wear resistance difference of up to 10 times, and the wide hardness range allows polyurethane to be used for various units, from soft seals to rigid rollers.

## How Hardness Affects the Lifespan and Maintenance of a Unit

As the hardness of polyurethane increases, so does its resistance to constant pressure and its ability to maintain shape, but its ability to absorb shocks and vibrations decreases. For parts operating under dynamic loads, the upper range of Shore A (80-95) is optimal. In this range, polyurethane prevents abrasives from cutting the material, and the unit maintains its operational parameters without frequent stops for replacement.

For seals and gaskets, where it's important to ensure tightness and elastic pressing against the shaft or housing, 70-90 Shore A is used. If a lower hardness is chosen, the seal wears out quickly; if higher, it may not 'grip' the working surface and lose tightness. Structural products (rollers, bushings, bands) that operate under static or cyclic loads are best made from polyurethane with Shore D hardness, where dimensional stability and resistance to wear under pressure are crucial.

With the correct hardness selection, the lifespan of a polyurethane part often exceeds that of a rubber or plastic equivalent by several times. Fewer maintenance stops, easier repair planning, and replacement once a season rather than monthly.

## Where Polyurethane of Different Hardness is Used in Practice

TIMOL factory produces polyurethane parts for 12 industries: from mining to food processing. In each industry, hardness is selected according to the working environment and type of load. For example:

- **Elevator buckets** (hardness 80-95 Shore A), used in grain elevators where wear and impact resistance are needed.
- **Wheels, rollers, bands** (Shore D), used in machinery, conveyors, and transport units.
- **Screens and vibrating screen parts** (80-95 Shore A), withstand abrasive wear and impacts from stones or ore.
- **Linings, sheets, and plates** (90-95 Shore A), for protecting chutes, hoppers, and gravity equipment from wear.
- **Gaskets, seals, packings** (70-90 Shore A), for sealing shafts, pumps, and hydraulic cylinders.
- **Bushings, rods, rings**, hardness is selected based on the part's role and load.

Each product is made by the free casting method according to the customer's drawing or technical specification. This allows for consideration of all the unit's and operating environment's features. You can view the range through the [polyurethane products catalog](/katalog).

## How to Order and Manufacture a Product of the Required Hardness

When ordering a polyurethane part from TIMOL, the customer provides a drawing, a description of working conditions (temperature, environment, load, abrasiveness), and engineers select the optimal composition and hardness of the polyurethane. The range, **from 50 Shore A to 70 Shore D**, allows for the production of both soft seals and rigid rollers.

Products are manufactured by the free casting method: this guarantees the absence of internal stresses, precise geometry adherence, and consistent quality throughout the part's volume. The installation of polyurethane parts depends on the type of unit: seals are pressed or placed in grooves, linings are mounted with bolts or glued with special adhesives. Parts are serviced just like similar rubber or steel ones, but with longer replacement intervals.

Additional materials on the selection, operation, and installation of polyurethane products can be found in the [reference information](/informatsiya) section. You can order a part to size or consult with a factory technologist through [contacts](/contacts).

## Conclusions: Why the Right Choice of Polyurethane Hardness is a Resource Guarantee

Choosing the right polyurethane hardness is a key factor that determines the durability and reliability of a unit. Only properly selected hardness allows for the full potential of the material: achieving wear resistance 10 times greater than rubber, maintaining elasticity or dimensional stability, and avoiding unnecessary stops for repairs. TIMOL factory manufactures polyurethane parts in the full hardness range (from 50 Shore A to 70 Shore D) for 12 industries. Contact us for consultation, hardness selection according to drawings, and product orders on the [contact page](/contacts).