When you work with PVC material suppliers, understanding hardness ratings like Shore A and Shore D will help you specify material that matches the demands of the components you’re manufacturing.
If you work in extrusion or moulding, you’ll find that these metrics play a major role in determining flexibility, processability and long-term performance.
Let’s take a look at what these ratings mean and why they’re important.
What Do Shore A and Shore D Actually Measure?
In short, Shore A and Shore D are indicators of hardness.
Hardness testing with a durometer gauges how far an indenter penetrates the surface of a material under a specific force. The scale runs from 0 (very soft) to 100 (very hard).
The “A” scale (Shore A) is used for softer elastomers and flexible plastics, while the “D” scale (Shore D) is applied to harder materials and more rigid plastics.
Both scales may overlap in the mid-range, but you’ll choose the correct scale based on the expected material hardness.
Why Does This Matter for PVC Components From a Supplier’s Point of View?
When your component needs to bend slightly, absorb vibration or seal against movement, you might work in a Shore A range. If it needs to hold its shape under load or endure abrasion, a higher SHA or a SHD rating may be more appropriate.
PVC compounds from IPC are available across both of these ratings, be it flexible, semi-rigid or rigid form factors.
Using the wrong hardness range may lead to warping, cracking or poor service life.
How Will You Decide Which Rating to Ask Your Supplier For?
First, you’ll need to map out the functional demands of your components. To do this, you need to ask yourself whether the part you’re making will need to flex under load or stay rigid and dimensionally stable.
Then check your processing constraints, as some compounds are easier to extrude or mould at certain hardnesses.
You should also look at the environment. Things like temperature, chemical exposure and wear will influence which hardness holds up best for your required application.
What is Some Practical Advice for Talking to Suppliers?
When you speak to your PVC compound supplier, first ask whether they use the correct durometer scale for your target hardness. Then confirm batch-to-batch consistency, as the hardness may be inconsistent if the formula or filler loading shifts.
Always keep track of how material hardness corresponds to outcomes so you can refine your spec for next time, if necessary.
If you’re ready to engage with PVC material suppliers who understand the difference between Shore A and Shore D in compound manufacturing and deliver consistently high-quality material, contact IPC today.
