The pellet compression testing machine is mainly used for pressure crushing test of various coking ore, and it can also be used for pressure test of other brittle materials. Comply with GB/T14201 "Method for Determination of Compressive Strength of Iron Ore Pellets", ISO4700 blast furnace and iron ore pellets for direct reduction feedstock---Determination of compressive strength, etc.
1. Introduction and application of testing machine
l Adopting precise auto control and data acquisition system to realize fully digital adjustment to data acquisition and control process. It can test max. bearing tensile, compression, tensile strength, deformation, elongation and other technical specifications;
l After test, the above parameters can be calculated automatically through main controller according to the test parameters, which are set before test and meantime display the corresponding test results. All test parameters can be saved and inquired after test, also can be connected with printer to print test reports.
2. Main functions of testing machine:
l with function of automatic return to original position, intelligently, efficiently, quickly;
l with limit protection function of any working position and overvoltage, over current protection functions, reliable, safe;
l With strong test data, which can save, inquire and retrieve test data anytime.
l with many control modes of constant speed control to force, stress, deformation, strain, stroke, load, elongation, displacement and low cycle and user self-programming control;
l Switch among many test curves: stress-strain curve, load-time curve, deformation-time curve, load-displacement curve. Partial enlargement, overlap and comparison.
3. Introductions of test method
Definition
Crushing strength: the applied maximum compressive load at which an iron ore pellet is broken completely, and which is expressed as the mean value of all measurements of test sample.
Taking of sample
The test sample (test pieces) for determining the crushing strength shall by obtained at random, for example by the use of a random selection plate, on about 1kg of the sample for physical testing. The test sample shall be oven dried at 105±5℃ and cooled to room temperature before testing.
Number of test pieces (iron ore pellets)
Sixty or more test pieces, or as agreed upon between the interested parties, shall be tested for each sample.
Test procedure
Place a test piece (single pellet) at the approximate centre of the surface-hardened portion of the lower platen. Apply the load at a constant rate between 10 and 20mm/min throughout the test period.
Record the maximum load, at which the test piece undergoes complete breakage, to at least one decimal place, in decanewtons.
Note: complete breakage is ensured by continuing to apply the load until the platen gap has closed to 50% of the average test piece size.
Clean the platens thoroughly before the next test piece(single pellet) is tested.
Repeat the procedure on the remaining test pieces.
4. Main technical specifications of testing machine:
No. | Inspection items | Technical specifications |
1 | Max. load | 10KN |
2 | Precision class | Class 1 |
3 | Measuring range of load | 1%-100%FS |
4 | Relative error of indicating value | ±1.0% |
5 | Min reading value of deformation | 0.01mm |
5 | Resolution of test force | 1/300000F.S (with constant resolution within the whole stroke) |
6 | Adjusting range of control rate of load | 0.005%-5%FS/s |
7 | Adjusting range of deformation rate | 0.005-5%FS/s |
8 | Control precision of deformation rate | When rate<0.05%FS/s, the precision is within ±1% of setting value; When rate ≥0.005%FS/s, the precision is within ±0.5% of setting value |
9 | Adjusting range of displacement rate | 0.01-500mm/min |
10 | Control precision of displacement rate | Within 0.2% of setting value |
11 | Effective test span | 360mm |
12 | Effective compression space | 400mm |
13 | Control mode | Computer |
14 | Power supply | 220V, 50Hz, 400W |
15 | Dimension of main machine | 410x660x820mm |
16 | Weight of main machine | 80kg |