Highlights
RUL/CIC 421 - Refractoriness Under Load and CreepCreep describes a time and temperature dependent plastic deformation under a constant force. When a constant force is applied to a rubber compound, the initial deformation obtained due to the application of the force is not fixed. The deformation will increase with time.Creep in Compression
Refractoriness under load (RUL, according to ISO 1893) is a measure of the deformation behavior of refractory ceramic products subjected to a constant load and increasing temperature. The temperature range in which the softening occurs is not identical with the melting range of the pure raw material; however it must be reliably determined with the RUL 421 to check the use of refractory products in high-temperature applications.
Measurements can be conducted in static air using the basic version or with an optional device for inert gas purge within the test piece area. For testing carbon-containing materials, such as magnesia-carbon graphite bricks, a non-oxidizing test atmosphere can be achieved using a gas-tight test chamber (optional). This chamber can be evacuated and purged with protective gas, allowing measurements to be carried out at temperatures up to 1600°C.
Optionally, the loading device can be equipped to allow for load variation. The preload can be set up to 300 N, while the verifying load can range from 0 N to 700 N, applied at a rate between 0.3 N/s and 3 N/s.
Generally, identical test piece dimensions of 50 mm in diameter and 50 mm in height are used for both the RUL and CIC tests. The high-precision differential measuring system used for determining expansion and deformation requires the cylindrical test piece to have a coaxial bore of 12.5 mm. The ground faces must be plane, parallel, and perpendicular to the cylinder's axis (ISO/DIN). Other test piece dimensions, such as 36 mm (GOST 4070-20000), are also possible.
The testing of refractories – clearly an essential process – includes the following applications:
- election of material
- Characterization of new materials
- Prediction of service conditions
- Quality control of the process and the product
- Failure analysis
- Mathematical modeling for product improvements
Method
Refractoriness Under Load and CreepCreep describes a time and temperature dependent plastic deformation under a constant force. When a constant force is applied to a rubber compound, the initial deformation obtained due to the application of the force is not fixed. The deformation will increase with time.Creep in Compression
Refractoriness under load (RUL) is a measure of the resistance of a refractory product to subsidence when subjected to the combined effects of load, rising temperature at a predefined heating rate. The range in which softening occurs is not identical with the melting range of pure raw materials, but it is influenced by the content and the degree of distribution of low Melting Temperatures and EnthalpiesThe enthalpy of fusion of a substance, also known as latent heat, is a measure of the energy input, typically heat, which is necessary to convert a substance from solid to liquid state. The melting point of a substance is the temperature at which it changes state from solid (crystalline) to liquid (isotropic melt).melting point fluxing agents.
RUL
The RUL test method is described in ISO 1893, Refractoriness under load (RUL, differential – with rising temperature). A cylindrical test piece (50 mm in Ø and height with coaxial bore of 12.5 mm) is subjected to a specified constant compressive load and heated at a specified rate until a prescribed deformation or subsidence occurs. The deformation of the test piece is recorded as the temperature increases, and the temperatures corresponding to specified proportional degrees of deformation are determined.
CIC
The instrument can also be used for the determination of CreepCreep describes a time and temperature dependent plastic deformation under a constant force. When a constant force is applied to a rubber compound, the initial deformation obtained due to the application of the force is not fixed. The deformation will increase with time.creep in compression (CIC) as described in ISO 3187. A cylindrical test piece is heated under specified conditions (see RUL) to a given temperature. While being held at that constant temperature, the deformation of the test piece is recorded and the percentage change is evaluated as a function of time.
Specifications
| Model RUL/CIC 421 E/6 | |
|---|---|
| Temperature range | RT to 1700°C |
| Heating elements | 4 Super-Kanthal 1800 |
| Test atmosphere | Static air; optional inert purge gas |
| Safety switch | Failure of test piece |
| Model RUL/CIC 421 G/6 | |
|---|---|
| Temperature range | RT to 1600°C |
| Heating elements | 4 Super-Kanthal 1800 |
| Protective tube | Al2O3 |
| Ability to evacuate | Up to 10-2 mbar |
| Test atmosphere | Static/dynamic air and inert gas |
| Safety switch | Failure of test piece, cooling water |
| General Data | |
|---|---|
| Test piece | Ø 50 mm, height 50 mm |
| Load range | 1 N to 1000 N; steps of 1 N to 100 N |
| Max. StressStress is defined as a level of force applied on a sample with a well-defined cross section. (Stress = force/area). Samples having a circular or rectangular cross section can be compressed or stretched. Elastic materials like rubber can be stretched up to 5 to 10 times their original length.stress | 0.5 N/mm2 |
| Measuring range | 20 mm; resolution 4,000,000 steps |
| Measuring system | Differential |
| Digital resolution | 5 nm |
| Thermocouples | Type B |
| Power Supply Electronics |
|
| Dimensions |
|
| Weights |
|
Brochures and Data Sheets:
Proven Excellence in Service
At NETZSCH Analyzing & Testing, we offer a comprehensive range of services globally to ensure the optimal performance and longevity of your thermoanalytical equipment. With a track record of proven excellence, our services are designed to maximize the effectiveness of your devices, extend their lifespan, and minimize downtime.
Unlock the full potential of your equipment with our tailored solutions, backed by years of industry expertise and innovation.
Software
State-of-the-Art Software Including Various Evaluation Routines
The RUL/CIC runs under Proteus® software on Windows® for the fully automatic test run, data acquisition, storage and off-line evaluation.
The analysis process includes both graphic and tabulated results calculated according to ISO/DIN standards. Key features of this process involve the correction of measured data using calibration curves and the determination of characteristic data tailored to user requirements. The system provides automatic detection of the softening point and derives curves for determining temperature- or time-dependent linear expansion rates.
There are options for temperature control, allowing for up to 96 IsothermalTests at controlled and constant temperature are called isothermal.isothermal or dynamic temperature program steps. The measurement values are presented either temperature- or time-scaled for Refractoriness Under Load (RUL) and time-scaled for the CreepCreep describes a time and temperature dependent plastic deformation under a constant force. When a constant force is applied to a rubber compound, the initial deformation obtained due to the application of the force is not fixed. The deformation will increase with time.Creep in Compression (CIC) test. The process also includes the determination of the absolute maximum in the length dilatation spectrum for RUL and the sample temperature 2.5 hours after the start of the IsothermalTests at controlled and constant temperature are called isothermal.isothermal phase for CIC.
Additionally, the system can determine relative length changes at preset times, calculate CreepCreep describes a time and temperature dependent plastic deformation under a constant force. When a constant force is applied to a rubber compound, the initial deformation obtained due to the application of the force is not fixed. The deformation will increase with time.creep rates within preset time intervals, and perform simultaneous analysis of up to 8 curves or temperature segments for curve comparison. It also allows for the calculation of single values of physical or technical expansion coefficients and provides the calculation and graphic display of the first and/or second derivative, including peak determination.
Related Devices
Consultancy & Sales
Do you have further questions about the instrument or the method and would like to speak to a sales representative?
Service & Support
Do you already have an instrument and need technical support or spare parts?
