Necessary conditions to cause a dust explosion
Rubber is an important raw material in the production of hoses, and the reason why rubber is so popular is that it has some advantages. Next, Orientflex will briefly introduce the physical properties and indicators of rubber.
- High elasticity: Low elastic modulus, large elongation deformation, recoverable deformation, and can maintain elasticity in a wide range of temperature (-50~150℃).
- Viscoelasticity: Rubber material in the deformation and recovery of deformation by temperature and time, show obvious stress relaxation and creep phenomenon, under the action of vibration or alternating stress, produce hysteresis loss.
- 3. Electrical insulation: Rubber and plastic are electrical insulation materials.
- 4. Aging phenomenon: Such as metal corrosion, wood decay, rock weathering, rubber will also be due to the change of environmental conditions and aging phenomenon, so that the performance is deteriorated, life decline.
- 5. Must be vulcanized before use, except for thermoplastic elastomer.
- Complexes must be added.
Other characteristics, such as small specific gravity, low hardness, good softness, good air tightness and so on, are valuable properties of rubber.
Physical and mechanical properties of rubber indicators:
- Tensile strength: Also known as tearing strength and tensile strength, refers to the load borne by the test piece on the unit section when it is stretched to fracture, the unit is Mpa (MPa), formerly kilogram force/square centimeter (KGF /cm2).
- 2. Constant extension stress: the old said constant extension strength, refers to the sample is stretched to a certain length of the unit area of the load.The unit of measurement is the same as tensile strength.Commonly used are 100%, 300% and 500% constant extension stresses.
It reflects the rubber resistance to external deformation ability.
- Tearing strength: The load borne per unit thickness of the special test piece (with cut or right Angle shape) when it is torn, indicating the tear resistance of the material, the unit is kN/m.
- Elongation: When the test piece is broken, the ratio of the elongation part to the original length is called elongation;It’s expressed as a percentage.
- Permanent deformation: the percentage of the unrecoverable part of the standard distance elongation deformation in the original length after the sample is stretched to fracture.After the external force is removed and placed for a certain time (generally 3 minutes), represented by %.
- Resilience: Also known as impact elasticity, refers to the ability of rubber to recover after impact, expressed by %.
- 7.Hardness: refers to the rubber resistance to external pressure into the ability, commonly used to measure Shore hardness tester.The hardness range of rubber is generally between 20 and 100, the unit is Shore A.
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