The RPA meets the full range of testing requirements of the complete manufacturing process:
Incoming polymer characterization
Incoming raw material test
Master batch testing
Final compound testing
Cured compound testing
The RPA measures the viscoelastic properties of polymers and elastomeric compounds providing comprehensive data on key parameters such as:
Processability
Cure characteristics
Final cured properties
The high sensitivity of the RPA enables detection of small changes in types and levels of ingredients and subsequent variations in compound properties, with routine operation by factory personnel. The overall range and flexibility of the RPA allows rationalization of traditional laboratory tests and equipment, reducing testing complexity, testing time and costs.
RPA 2000 benefits
This advanced system can be configured to determine a wide range of product properties through all stages of rubber production.
Rapid test sequences enable:
Increased testing frequency compared to traditional techniques
Faster batch release, improving productivity
The RPA `s unique programmable testing capabilities permit much higher and faster discrimination between polymers and compounds than is possible by conventional methods.
Replace numerous traditional techniques:
Increase test efficiency and quality
Reduce testing costs
Eliminate many downstream production problems:
Increase production efficiency
Significantly reduce scrap and rework
Quality control (and development) of new generation compounds which cannot be effectively analyzed by conventional methods.
Major features
Advanced instrumentation
The RPA is designed with a range of variable test parameters to enable a wide range of physical properties to be measured.
The variable test parameters are:
Temperature
Oscillation frequency
Strain/angle of oscillation
Time
The RPA is delivered with a pre-programmed series of tests allowing the user to rapidly exploit this powerful tool.
This user friendly, flexible system enables the operator to obtain quality control data on processability, curing characteristics and final properties from a single sample. No complex sample preparation is required.
The sample is loaded into a sealed test cavity pioneered by Alpha Technologies. Two directly heated low mass biconical dies give fast, accurate thermal response. The required starting temperature for the test is set automatically and controlled by heating and/or forced air-cooling. The temperature can be varied up or down during a test, or maintained at a constant value to within +/-0.3 ºC.
The RPA is equipped with a direct drive servo motor system that can vary the oscillation angle (0.05 º to 90 º deg arc) and frequency (0.03 to 33 Hz) with high accuracy over a wide range of conditions.
The torque is transmitted via the sample from the oscillating lower die to the highly sensitive torque transducer positioned in the upper die. The measurements made by the torque transducer are fed into the system computer. This calculates the selected sample properties, displays the results and stores the data for further analysis.
The advanced software control eliminates operator intervention from sample loading until the test sequence is complete and the required data produced.
Further productivity increases are obtained when the automation option is fitted. This option allows up to 100 samples to be measured without operator involvement, and consists of a rotary tray staging system; sample loading arm, film transport system and controller. Alpha Technologies has pioneered the use of polyester for polyamide films for sample testing and transport, which give additional benefits in respect of reduced die contamination and increased seal life. The unit comes complete with Alpha Technologies` RPA software, computer, and color monitor and color printer.
Enhanced testing
The reaction of the sample to the preset conditions is measured and the sample properties determined as follows.
Variable strain
Strain is applied, via the oscillating lower die, under full computer control. The strain angle can be precisely varied between 0.05º and 90º in 0.01º increments. Torque, modulus and viscosity are measured at a pre-programmed frequency and temperature.
Variable frequency
The oscillation frequency of the applied strain can be varied precisely between 0.03 and 33Hz.Torque, modulus and viscosity are measured at a pre-programmed strain and temperature.
Variable temperature
The temperature can be precisely varied during a test between 40 ºC and 230 ºC. Torque, modulus, and viscosity are measured under pre-programmed frequency and strain.
Multiple test sequences
The RPA enables a series of tests to be performed on a single sample in a programmed sequence providing complete data on the viscoelastic and rheological properties of the sample, before during and after cure.
Additional features:
Stress relaxation - Modulus and torque are measured against time after the sample is subjected to pre-programmed strain.
Delay -Sample ageing and conditioning at programmable time, frequency, strain and temperature.
Matrix -Specialist applications. A combination of modulus, torque and viscosity are measured under programmable strain, temperature and frequency.
Cure -Modulus and torque are measured against time under isothermal conditions at pre-programmed strain and frequency.
Sample cutter 2000R
This robust cutter is recommended to minimize sample preparation time and maximize productivity. The dual action pneumatically operated press provides rapid, precise preparation of constant -volume samples for testing, thereby optimizing repeatability and reproducibility.
System options
Automation -The system is under full computer control allowing different, complex test sequences to be performed on up to 100 different samples, without operator intervention
Pressure -enables the blowing characteristics of sponge materials to be measured at the same time as cure properties
Low viscosity -The RPA is available with a torque transducer specifically designed to measure the characteristics of low viscosity materials, including thermoplastics (PVC, polyolifins, ABS, polystirene, polyamides) and thermoplastics rubbers (TPR, TPV, TPU, TPE)