Computerized sponge compression strength testing machine
1. introductions
The microcomputer-controlled sponge pressure testing machine is equipped with a compression platen, which can be used to test the compression properties of thermal insulation sponge, thermal insulation sponge, sound-absorbing sponge, sound insulation sponge, sponge scouring pad, fire-retardant sponge, sofa sponge and other products, such as compressive strength, the compressive stress and compressive elastic modulus at 10% deformation, the tensile properties of the material can also be tested when equip with tensile test fixtures.
2. relative test method for sponge compression strength test
GB/T 13480 , ISO 29469 thermal insulating products for building applications – determination of compression behaviour
ASTM D3574 standard test method for flexible cellular materials – Slab, bonded, and molded urethane foams
3. Relevant test methods for design, manufacture and inspection of sponge compression strength testing machine
GB/T2611 general requirements for testing machines
GB/T16491 electronic universal testing machine
GB/T16825.1 verification of static uniaxial testing machines --- part 1: tension / compression testing machines --- verification and calibration of the force measuring system
ISO7500-1 metallic materials--- verification of static uniaxial testing machine --- part 1: tension / compression testing machines --- verification and calibration of the force measuring system
ASTM E4 standard practice for force verification of testing machines
EN 10002-2 tensile testing of metallic materials --- part 2: verification of the force measuring system of the tensile testing machine
4. technical specifications
How to Select the Right Tensile, Compression, Bending, Shear, Peel, and Tear Testing Machine: Calculation Formulas with Examples
Selecting the appropriate testing machine for tensile, compression, bending, shear, peel, and tear tests requires careful consideration of multiple factors, including the force range, specimen dimensions, test standards, and machine capabilities. Below are the key calculation formulas to help determine the necessary machine specifications, along with examples for better understanding.
1. Tensile Testing Machine Selection
Tensile testing machines measure the maximum tensile strength and elongation of materials.
Key Formula:
Fmax=σmax × A
Where:
Fmax = Maximum required force (N)
σmax = Ultimate tensile strength of the material (MPa)
A = Cross-sectional area of the specimen (mm²)
Example: For a steel specimen with σmax =400MPa and cross-sectional area A =100mm²:
Fmax=400 × 100=40,000N (40kN)
A 50 kN tensile testing machine would be suitable.
2. Compression Testing Machine Selection
Compression tests determine a material's resistance to compressive forces.
Key Formula:
Fmax=σc × A
Where:
Fmax = Maximum required force (N)
σc = Compressive strength of the material (MPa)
A = Cross-sectional area of the specimen (mm²)
Example: For a concrete cube with σc =30MPa and A =1502=22,500mm²:
Fmax=30 × 22,500=675,000N (675kN)
A 1000 kN compression testing machine would be ideal.
3. Bending Testing Machine Selection
Bending tests evaluate the flexural strength of materials.
Key Formula for Three-Point Bending:
Where:
σf = Flexural stress (MPa)
F= Applied force (N)
L= Span length (mm)
b= Width of the specimen (mm)
h= Thickness of the specimen (mm)
Example: For a wooden beam with L=500mm, b=50mm, h=25mm, and requiring a stress of 10 MPa:
A 5 kN bending tester would be suitable.
4. Shear Testing Machine Selection
Shear tests determine the shear strength of materials.
Key Formula:
Fmax=τ × A
Where:
Fmax = Maximum shear force (N)
τ= Shear strength of the material (MPa)
A = Shear area (mm²)
Example: For an aluminum sheet with τ=90 MPa and A=200mm²:
Fmax=90×200=18,000N(18kN)
A 20 kN shear testing machine is recommended.
5. Peel Testing Machine Selection
Peel tests measure the adhesion strength between bonded materials.
Key Formula:
Where:
P= Peel strength (N/mm)
F= Measured force (N)
W= Width of the specimen (mm)
Example: For a tape with F=50N and W=25mm:
A peel testing machine with at least 5 N force capacity is required.
6. Tear Testing Machine Selection
Tear tests determine the resistance of a material to tearing forces.
Key Formula:
Where:
Ftear= Tear strength (N/mm)
F= Measured force (N)
t= Thickness of the specimen (mm)
Example: For a rubber sheet with F=100N and t=2mm:
A tear testing machine with 100 N capacity is needed.
When selecting a testing machine, ensure that the maximum force capacity of the machine is at least 1.2 to 1.5 times the calculated force to account for safety margins and unexpected variations. Additionally, consider compliance with relevant test standards (ASTM, ISO, GB, EN, JIS) and machine features such as speed control, data acquisition, and test automation.
By using the above formulas and examples, engineers and manufacturers can accurately determine the appropriate testing machine specifications for their specific material and application requirements.