1. Cooked grain dryer grain
The harvest of grain because of repeated by the sun, rain, dew, wet thousands, cooked to a certain amount of crack, and its water content is less, according to the normal speed for drying in the drying machine, is bound to make the crack rate further increased. Therefore, should be timely harvesting crops, in the drying process, as the mature degree appropriate to reduce the inlet air temperature, under normal circumstances can use the specifications of various models of lower than 3 ~ 4 ℃.

2. Grain drying machine drying grain case off more or injury
Watchcase stripping grains, drying surface evaporation is not uniform, rice show part of fast drying, easy to crack; high wet material drying machine drying machine at the same time, compared to complete the final drying grain, more general grain drying, forming and drying. So the case injured grain is easy to produce crack. Grain damage is mainly due to the harvest machinery injury, therefore, combine harvester to correctly adjust the cutting table, transportation, threshing unit. During the drying process, should try to adopt low temperature, slow drying.

3. Grain dryer hot air temperature is too high
Various drying machine according to its own characteristics, the inlet air temperature of different grains, reasonable selection of installed capacity requirements, in accordance with the drying speed is controlled in a certain range, to ensure the quality of grain. The operation such as selection of high blast temperature, crack rate will exceed the specified value. Therefore, must choose the parameters according to the requirements of the specification, only control the highest temperature models, inlet air temperature should be in commonly 45 ～ 55 ℃, the temperature in the valley below 40 ℃, and guarantee the dried grain quality.

4. The poor circulation of grain drying machine
Grain circulation, will cause some grain heating time prolonged, the temperature is high, the dehydration rate too fast, at the same time cycle is not uniform, the termination delay some grain drying, dry, cracked and more. The impurity more grain into the drying machine, not only causes uneven circulation, also produces severe overhead (without loops), clogging shut down fault, so the impurity more grains in the machine before you mount Yang Qing machine drying. High moisture grain poor liquidity, in order to prevent the poor circulation, can use a few grains after entering, side into the valley side circulation drying, rapid dehydration grain surface, improved flow properties of corn drying machine. In the process of operation, to check whether the uniform grain down, and make appropriate adjustments when necessary. Stacking type drying machine, in addition to strictly control the inlet air temperature, must according to the requirements of the manual turn over and take the space heating methods.

5. Grain drying machine loading grain too little
Batch type recirculating grain dryer installed capacity in rated grain in the machine, a drying cycle time required is about 1H,about 15min heating, the other 45min not heating (tempering),through its own internal heat, let the water to the surface diffusion equilibrium, the drying temperature can be controlled at the specified temperature. As the grain filling reduced, a cycle time is shortened, and the drying time is the same, therefore, the grain temperature rising speed, drying, tempering time reduced, moisture diffusion balance is not sufficient, the crack rate increase. So when the grain into too little and must drying operation, which should reduce the inlet air temperature and the use of space heating method.

6. Grain dryer uneven grain moisture content
In the same batch of drying grain, moisture content is not uniform requirements of less than 3%. The difference is too large, when the dry end part, or have not yet reached the dry, or dry after all, part of a dry and cracked. If you need the same batch drying, can be performed at room temperature water cycle, reduce the gap, and then into the hot normal drying stage. Or used by the two drying method, the drying to the grain moisture content 18%, stop operation 5h, the grain moisture balance between automatically, and then drying to the end.

7. Excessive drying of grain drying machine
Long term storage requirements of grain, dried to a certain moisture content (such as rice is generally 14%). Drying too, some chemical surface with water is evaporated, cracks, grain quality, and weight reduction, but also a waste of energy, increase the cost, therefore, drying operation close to the requirements, should pay attention to timely determination of moisture content, automatic shutdown device models, bean dregs dryer set correctly stop water ratio or shutdown time, found to have errors, promptly corrected.

9. Grain drier outside dry climate
Dry weather, the air humidity is small. Then drying quickly will cause the crack to increase. When the outside air humidity below 65% when the air temperature is low, the value of 3 ~ 4 ℃ than manual index.

10. Grain drying machine drying grain handling
The drying operation is completed, such as send wind cooling, grain surface suddenly contraction, induced crack. Under normal circumstances, should be avoided.

11. The grain drying machine mechanical injury
Conveying part dryer sloshing, abrasion, impact, will directly damage the case or a grain of rice, resulting in crack. Therefore, conveying part should always check and adjust, collision is removed in time, ladle wear give change, bucket elevator deflection, relaxation, should adjust to the normal state.