Chapter III Inspection standards for Rice mill Rubber Roller

　　(l) Tearing strength:Strength refers to the ability of the material to resist damage under the action of external force. Strength refers to the ratio of the relay to the cross-sectional area of the initial test piece when the rubber test piece is stretched to break, and the unit is MPa( kg/Cm2). For the rubber roller, this is an important mechanical performance, the rubber roller in the process of grinding rice with a variety of external forces, and for high-speed intense mechanical movement, which requires the rubber material must have a high strength, otherwise it will reduce the use of rubber roller value.

　　

　　(2) Elasticity:It is one of the most important properties of rubber materials. It refers to the performance that rubber deforms under the action of external force and returns to its original state after the external force is removed. There are many indicators to measure elasticity, such as: constant stress elongation, elongation, tear-off permanent deformation and heat generation, etc. For husking rubber rollers, moderate elasticity is required. Although high elasticity can improve the peeling ability, reduce the phenomenon of explosion waist, broken rice and so on, but the elasticity is too high, easy to produce large elastic deformation, increase the heat generation, so that the working temperature of the rubber roller increased, reduce other mechanical and physical properties of rubber. Such as: hardness will be reduced, can not be used. The elasticity is too low, the hardness is too high, the wear resistance is poor, and it is easy to cause injury.

　　

　　(3) Hardness:Hardness refers to the ability of rubber to resist deformation when it is compressed by external force. Generally take the Shore A hardness tester to measure its value, the rubber roller in general, the hardness requirements are more stringent. Too high will increase the rubber roller glue consumption and broken rice, too low will reduce the shelling rate. Hulling rollers according to different regions, seasons and other conditions of use (such as rice, temperature, etc.) should be equipped with different hardness values. Generally, the hardness of rubber rollers has three tolerance ranges of 90, 92 and 95 degrees, all of which are within 3 degrees. It should also be pointed out that the above-mentioned hardness is not a fixed value. Depending on the production season, its value is measured at standard temperature (230°C 2) and standard sample. However, the hardness value of rubber rollers in actual operation is different from the rated value of rubber rollers and is generally reduced.

　　

　　(4) Anti-aging dip:The so-called aging refers to the rubber in the long-term storage and use process, due to the oxygen in the air, odor, heat, light amplitude rays and other fatigue physical and chemical effects, so that the quality of rubber deterioration. Important physical and mechanical properties are degraded and scrapped, and the aging of hulling rollers is characterized by hardening, brittleness, cracking and mold growth,

The elastic strength and other properties of the rubber material are greatly reduced, which seriously affects the use effect. Although the rubber roller has taken many anti-aging measures during production, it is still very important to do a good job in anti-aging work.

　　

　　(5) Balance:Balance refers to the ability of the rubber roller to maintain a fixed rotary axis when rotating. Strictly speaking, it is a kind of dynamic balance. However, because the rubber roller does not belong to precision mechanical parts and the dynamic balance is not easy to measure, the concept of static balance is actually adopted. That is, the symmetry of the quality of each part relative to the working axis is commonly known as "partial weight", the balance of the rubber roller has a significant impact on the shelling rate, brown rice rate, rubber consumption and the normal operation of the husker.