Compression Set Test Device QualiCST-815
This Compression Set device meets ISO 815, ASTM D395 Method B, and DIN 53 517 standards.
The Compression Set Test device evaluates how well rubber maintains its elasticity after extended compression under constant strain (typically 25%) at specified temperatures and deformation conditions.
For rubber with a nominal hardness between 10 IRHD and 80 IRHD, a 25% strain is typically applied. Harder materials require reduced strain: 15% for hardness levels from 80 IRHD to 89 IRHD and 10% for those between 90 IRHD and 95 IRHD.


How to Perform the Test:
- Place the samples between the test plates.
- Insert the three spacers required to achieve the desired deformation.
- Tighten the bolts until the plates make contact with the spacers, applying the intended deformation.
- Place the entire device in an oven, set to the specified temperature, for the required test duration.
- Remove the device from the oven and measure the permanent deformation using the procedure outlined in the standards.
Optional Compression Set Software: Store Your Results!
This software enables you to record thickness measurements directly from the comparator (connected via USB) and calculate Compression Set test results.
Key features include:
- Identifying specimens
- Selecting the processing method used
- Entering initial and final thickness values, along with spacer thickness
- Calculating Compression Set values in compliance with standards
- Comparing results against tolerance limits and storing data in the SQL database
- Generating reports and statistical analyses
Calibration Report for the Compression Set Device
Each Compression Set device comes with a unique identification label and a Calibration Report, ensuring traceability to the reference instruments used.
The Calibration Report includes:
- Surface roughness measurements, verified according to standard requirements.
- Spacer thickness measurements taken at three points.
Aluminum Handle and Optimized Design for Easy Handling
Compression Set devices require frequent handling and placement in ovens, making one-handed operation a valuable advantage.
The solid anodized aluminum handle enhances grip without increasing the space required inside the oven.
The plates are designed for optimal rigidity while keeping weight low:
- 3-plate device: 11.5 kg
- 2-plate device: 8 kg
3-Bolt Closure for Faster Setup
The device features a 3-bolt closure system, allowing the upper plate to be secured quickly and efficiently. The bolt heads are recessed into the base plate, eliminating the need for two wrenches.
This design reduces preparation time by 25%, improving workflow and ease of use.

Three-Plate Device Construction
The 3-plate model is designed for high-volume testing, allowing up to 24 ISO 815-1 Type A specimens to be tested in a single run.
For greater flexibility, the intermediate plate can be added or removed based on testing requirements.
The total weight of the assembled device is 11.5 kg.
Two-Plate Device Construction
The 2-plate model is a lightweight, versatile option, capable of testing up to 12 ISO 815-1 Type A specimens at once. It is ideal for laboratories where specimens arrive at different times.
The total weight of the device is 8 kg.
Optimized Surface for Maximum Specimen Capacity
The device's efficient design allows testing of up to 12 ISO 815-1 Type A specimens simultaneously.
In comparison, a rectangular device with the same surface area could accommodate only 8 specimens.
Support Base: Fast and Safe Assembly & Opening
Assembling and opening the device can be demanding and pose some risks. The specially designed support base can be securely locked in a vise, preventing movement during operations.
This setup allows the use of an automatic screwdriver, eliminating the need for wrenches—making your Compression Set device as efficient as a pit stop.
Mould for Sample Preparation
- Mold for preparing test samples
- Thickness meter for measuring sample thickness

Interchangeable Silicone Feet: Safer Handling & Lab Protection
The interchangeable silicone feet minimize sharp edges and angular surfaces, reducing the risk of impact and noise during frequent handling. This enhances both safety and workplace comfort in the laboratory.
Equilateral Triangle Construction
The equilateral triangle design, combined with 18 mm thick plates, prevents deformation—even when testing a large number of high-hardness specimens. This ensures uniform deformation across all specimens for accurate and consistent results.
Development & Production
- All mechanical parts are produced in-house using modern CNC machines for precision.
- High-quality components and sensors from trusted brands ensure maximum measurement reliability.
- Skilled in-house personnel oversee every stage, including assembly, startup, calibration, packaging, shipping, and installation.