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Technical parameters

Parameters and use characteristics of hulling roller and the Technical Notes

  The first chapter hulling roller Profile

  Since the rubber roller hulling machine to replace sand tray hulling machine and iron roll rice mill, rice milling industry became specialized equipment for rice shelling, with its high production capacity, shelling rate, low broken rice, power consumption, and easy operation are the major Mega factories widely used. With the increasing development of the rice milling industry, rubber roller hulling machine constantly strive to improve and increasingly sophisticated. Such as: single transmission gearbox hydraulic tight roller hulling machine appears, it is undoubtedly a replacement product, but no matter how it tends to complex structures, how to improve performance, always remain the same, the basic principle is the same , that is, by means of reverse next two rubber roll is not constant rotation, so that the rolling of rice by squeezing, rubbing and other effects of the tear, to achieve the purpose of the shelling. So hulling roller hulling machine is the essential consumable parts.

 

  The basic characteristics of the second chapter hulling roller and the performance
  Cots classification, structure and type:

  At present, China and hulling roller comprises three major international, also known as the three major series, were named: Wheel, sets, take the formula.
  Wheel: The center flange hole location, three or four bolt holes fixed on two hulling machine spindle.
  Nested: both ends 46o cone positioned to tip ends of the sub-groove within the cone, fixed on two hulling machine spindle taper and the cap is secured.
  Take the formula: take the child to both ends of the hole positioned to take the top ends of the screws should be fixed on the two hulling machine spindle.

 Hulling roller old model specifications table

Series

Specifications

Old Specifications

length mm

An outer diameter mm

Effective adhesive thickness mm

LGL63

21/2''

63

152

14.5

L series

LGL100A

小4''

100

182

18

LGL100B

4''

100

222

19.5

Wheel

LGL152

6''

152

222

19.5

LGL178

7''

178

222

20.5

LGL200

8''

200

225

25

LGL220

9''

220

225

30

LGL254

10''

254

255

24.5

LGL300

12''

300

270

30.5

T series of nested

LGT355

14A''

355

227

29.5

LGT457

18A''

457

232

30.5

LGT508

20A''

508

255

30.5

LGT635

25A''

635

255

30.5

  Cots outer color: brown, white two kinds, as well as in foreign countries, beige, blue and gray.
  Cots outer rubber hardness (Shore A Tai-type) have 90o, 95o.

  Basic performance hulling roller:

    Basic performance hulling roller (grinding grain level of the number) depends on the external rubber physical and mechanical properties, can be described as follows:

  (1) Tensile strength: strength refers to the ability to produce material to resist damage under external force, the intensity is defined as the rubber test piece is stretched to a ratio of the initial test piece and the relay of the cross-sectional area of ??the fracture with the unit is MPa ( kg / Cm2). for Cots, this is an important mechanical properties, rubber roller rice mill in the course of action to be with a variety of external forces, and high speed severe mechanical motion, thus requiring the compound must have a high strength, otherwise it will reduce the value of the use of rubber roller.
  (2) Flexible: is the rubber material of the most important properties, it refers to the deformation of the rubber occurs in the external force, the external force is removed after restitution performance. Many indicators to measure the elasticity, such as: given stress elongation, elongation at break and generate heat and other permanent deformation of hulling roller terms require elastic medium. Although the high elasticity can improve the ability to peel, reducing fissuring, less broken rice and so on, but the flexibility is too high, easy to produce large elastic deformation, increase the generation of heat, so that the rubber roller temperature increase, decrease other mechanical rubber physical properties . Such as: hardness decreases, it can not be used. Elasticity is too low, too high hardness, wear resistance is poor, could easily lead to injury break.
  (3) Hardness: Hardness refers to the ability to resist deformation of the rubber compression invasion by external force. In general, Shore A hardness measured value of the rubber roller In general, the hardness of the more stringent requirements. Too high will increase the consumption of plastic and rubber roller broken rice husking rate will be reduced more than low. Hulling roller should be equipped with different hardness values ??according to different regions, seasons and other conditions (such as rice, temperature, etc.). Usually rubber roller hardness of 85o, 90o, 95o are three kinds of tolerance within ± 3 degrees, also to point out the hardness of the above is not a fixed value, with the production of different seasons, its value at standard temperature (23 ℃ ± 2o) and the standard the sample under measurement, hardness values ??and ratings and rubber roller rubber roller when the actual work is different, usually reduced.
  (4) anti-aging properties: the so-called aging refers to the rubber in the long-term storage and use, due to physical and chemical effects of fatigue oxygen in the air, smell, heat, light, radiation line, so that the deterioration of the quality of the rubber, it is important physical and mechanical properties decline, retirement, aging performance after hulling roller is hard and brittle, cracking and mildew phenomenon, elastic strength compound properties dropped significantly, seriously affect the results, even though the production of rubber rollers when taken many anti-aging measures, but do a good job aging work is still very important.
  (5) Balance: Balance refers to the rubber roller to maintain a fixed rotational axis capability in the rotation, strictly speaking, is a dynamic equilibrium, but because Cots are not precision machinery parts, and balancing difficult to measure, so in fact using static balance with the notion that through each part of the quality of work with respect to the axis of symmetry, commonly known as "biased", Cots balance is good or bad for husking rate, the rate of brown rice, rubber consumption and functioning are hulling machine have a significant impact.
  The third test chapter hulling roller
  Enterprise Standard: ministerial standards and foreign standards
  Enterprise standard: enterprise standard higher than the general ministerial standards
  Rubber physical and mechanical performance requirements:
  Tensile strength: MPa 19 (190K / cm2) above
  Elongation at break: 200% or more
  Energy consumption reduction cm3 / 1.61km <0.5
  :( Hardness Shore A) 85o 90o 95o
  Tolerances ± 3o, the same rate of hard rubber roller on the highest and lowest difference is greater than 2o.
  1 with SBR rubber rollers do
  Rubber specimens: Tensile strength: MPa 23-25
  Elongation at break 290-350%
  Abrasion loss Cm3 / 1.61km 0.19-1.05
  :( Hardness Shore A) 95o-96o
  2, nitrile rubber made of brown rubber roller
  NBR: N230; N220; 41 etc.
  Rubber specimens: Tensile strength: MPa 24-26
  Elongation at break 300-360%
  Abrasion loss Cm3 / 1.61km 0.08-0.15
  :( Hardness Shore A) 95o-97o
  3, with the small plastic do stupid white cot
  Rubber specimens: Tensile strength: MPa 22-24
  Elongation at break% 280-300 × 320
  Abrasion loss Cm3 / 1.61km 0.15-0.10
  :( Hardness Shore A) 94o-95o
  4, with the nitrile rubber and PVC made white cot
  NBR: N230; N220; 41 etc.
  PVC: suspension PVC-SG4-6 type
  Rubber specimens: Tensile strength: MPa 24-25
  Elongation at break 300-350%
  Abrasion loss Cm3 / 1.61km 0.06-0.1
  :( Hardness Shore A) 96o-98o
  Proper use of Chapter IV hulling roller
  First, the plastic shell of rice processing conditions:
  Grain husking process typically go through three basic steps: extrusion, rub tear, peel, which is the key to shelling tear rub, rub tear size depends on two important factors: First, the size of the friction, and friction the size and the size depends on the pressure between the two rollers; the second is the length of the reverse friction in grain relative roles of the time, and the length of time this effect in turn depends on the relative speed of the two rollers, the line speed difference related . Easy to see: the difference between the pressure roller and the line speed is important process parameters rice shelling, its choice is correct or not directly affect the husking rate, also affects the consumption of rubber rollers.
  Second, the process parameters of the general principles:
  Milled rice the amount of rubber roller is actually a comprehensive reflection of the husking rate and the rubber consumption, the interaction between the two and both mutual restraint, the so-called optimum state refers to both a higher rate of shelling there lower glue consumption, this is the choice of the general principles of the process parameters.
  1. The line speed difference selection: line speed difference is too large, it can enhance the rub tear strength, improve the husking rate, but also increases power consumption and wear rubber roller. Line speed difference is too small, shelling rate, less consumption off the back hulling increase the total amount of crushed rice is not high, visible select line speed difference must be balanced against the husking rate and gum consumption two aspects, one-sided pursuit of any indicators are wrong. In my many years of experience, the line speed difference select 2.4-3 m / s as well, when the line speed difference is less than two meters when the shelling was significantly decreased (hulling machine fast roller speed of 1350 rev / sec, slow roll speed 1150 rev / sec; ratio of 1: 1.17), rice huller rubber roller constantly at work wear, the line speed difference time narrowing, and a faster roll staggering, to guarantee a certain technical effect, you have to maintain a certain line speed difference, when the fast slow roll diameter smaller than the diameter of the roll, they immediately replace the fast roll. Usually fast roll diameter greater than the slow roll diameter 2-10mm, in practice, the line speed difference and selected on the basis of many factors, such as rice varieties, chaff thickness, tightness, moisture content and weather conditions Wait.
  2. Choose between roller pressure: pressure between rolls also tear force size pickup one of the key process parameters on the pressure roller hulling machine pressure by the pressure between the rollers to adjust the lump weight, in principle, easy to light weight is not easy, balanced on both sides , with the rubber roller can increase pressure gradually wear appropriate lump weight; for manual tight roll hulling machine, the distance between the rolls of a width equal to the thickness of a grain of rice is appropriate, and generally 0.5 (indica) -0.8 (japonica) mm, should adhere to the ground less into the tight, parallel feed principle.
  Third, improve the methods and hulling roller life precautions:
  1. Cots reasonable choice: Black, brown, white, Shore hardness 90o, 95o of a roll to be a reasonable choice, according to rice varieties in the region, climate, season and other specific circumstances, with a reasonable, preferably fast choose some of the high rollers hardness, low hardness more slowly roll the election, to avoid a single species of rollers.
  2. Control Working temperature: Cots actual work during grind rice Shore 78 o-82 o more appropriate. According to the determination: working temperature of 50 ℃ is appropriate (when the temperature above 60 ℃, the hardness of the rubber roller drop 4-8 degrees).
  3. The implementation of more than just rubber roller used interchangeably: this approach can improve the life of rubber roller and grind rice amount. Its advantage is that each has a work Cots intermittent time, help eliminate fatigue stress, restore rubber material performance, ease of use of different diameter adjustment line speed difference, but also effectively control the operating temperature.
  4. Strengthening custody Cots: good anti-aging work. Cots effective storage period is defined as one year, so plans to purchase adequate reserves, do a good job keeping the work, specific storage requirements are as follows:
  (1) should avoid direct sunlight and rain and erosion from the heating device is not less than 1.5 meters.
  (2) prohibition with acid, alkali, salt, oil and organic solvents and other substances affect the quality of rubber in contact, should be kept clean.
  (3) warehouse storage temperature is maintained at 10o? Between -30o, relative humidity at 50 o-80 o between.
  (4) Vertical rotation should not be placed horizontally or heap pressure other substances. Not allowed to strike, to avoid deformation and damage.
  Fourth, the rubber roller in the course of the irregularities and the causes:
  1, the size of the head to produce rubber roller;
  Reason: 1 two pressure lump uneven weight;
  2 rolling from improperly adjusted;
  3 rice or eliminate uneven flow deflection plate;
  4 two roll axes are not parallel.
  2. Cots middle convex or concave in the middle:
  Reason: 1 concentrated stream layer or uneven;
  2 drip plate uneven;
  3 gate wear or crescent;
  4 Cots size of the head, just pay attention to tight bulk.
  3. The rubber roller surface from the bad:
  Reason: 1 Net valley containing hard impurities;
  2 line speed difference is too large, too small or roll from pressure lump too heavy;
  3 hulling machine shake seriously;
  Note that only 4 or high moisture paddy husking rate adjustment roll away without paying attention to adjust line speed difference.
  4. The rubber roller Working temperature:
  Reason: a poorly ventilated;
  2 line speed difference is too large between the rolling pressure, rolling distance is too small;
  3 Press hulling containing too rough;
  4 in direct contact with the two rollers
  5. From the aspect corrugated roller surface:
  Cause: dirty rice 1 poor;
  2 line speed difference or rolling from improper selection;
  3 Cots loose;
  4 static balance allowed.
  6. Cots excessive wear and tear:
  Reason: 1 two roller line speed difference is too large, the husking rate is too high;
  2 rolls pressure is too large, rolling away from tight;
  3 rice containing impurities and moisture is too high;
  4 rubber roller temperature is too high;
  5 Cots selection of high hardness.
  7. The rubber roller deformation:
  Cause: 1 improper placement of storage, aging or partial melting;
  2 static balance correction allowed counterweight wrong location;
  3 Cots and high operating temperatures
  4 rice husking difficult time, continuous long working hours.
  8. Cots blistering, peeling:
  Reason: 1 Cots good quality water
  2 Cots aging;
  3 direct friction between the rolls for too long;
  9. The rubber roller off the core, burst, collapse glue:
  Reason: 1 Cots poor quality;
  2 long time storage.
  10. The rubber roller from the edge:
  Reason: 1 Cots itself does not length;
  2 two-roll installation length misaligned.