The quality of the grinding roller repair quality directly affects the production of various indicators, should strive to achieve excellence. Efforts have been made to catch up with the technical requirements for the introduction of wire-drawing rolls and sandblasting rolls to ensure the smooth completion of production processes and product quality.

1. Purchase and arrangement of polishing wire drawing machine

The purchase of the polished wire drawing machine should be carried out according to the specifications of the mill's grinding machine, and the processing can be slightly larger than the length of the grinding roller of the factory.

The top view of the polished wire drawing machine is like a "convex" word. The installation should be considered at the widest point. The side is not less than 300~500mm away from the wall. It gives the operator room for manoeuvre when the side is fed.

The safety distance between the fixed dust cover and the wall at one end of the work surface should be a minimum of 500mm for easy operation and maintenance.

2, the basis and installation of the polishing wire drawing machine

It is the basis for ensuring the long-term stability of the machine tool. The following are common:

The foundation pit is dug on the ground, and its depth depends on the soil condition, generally 500-600mm, and is compacted with layers of three-layer soil. In order to make the integrity good, the steel bars should be bundled. The machine can be placed in one step or twice. The plane of the machine base should be 50 to 100 mm above the ground.

When installing the machine on the floor of the milling workshop, the secondary beam should be appropriately added according to the weight and vibration requirements of the machine to ensure the normal operation of the machine.

After the machine tool is installed in position, use the ordinary level, combined with the adjustment block at each anchor bolt, to make the vertical and horizontal preliminary leveling, and tighten the nut.

In order to further fine-tune the level of the bed surface, the workbench should be removed, and the horizontal and horizontal levels of the plane guide rail of the machine tool should be verified with a frame level 0.025.

In order to further fine-tune the overall level of the machine tool guide rail, the overall level of the V-shaped groove and the guide rail can be detected by the bridge method to make it within 0.03 mm. At this time, reinstall the workbench and other accessories, install a grinding roller, turn on the power supply for the idle operation test, and after the worktable reciprocates for a period of time, remove the grinding roller and the workbench to check the guide surface of the workbench. The percentage of the contact surface with the pedestal is only qualified if the contact surface reaches 70% or more.

3, the transmission mode of the polishing wire drawing machine

Due to the overall transmission of the shaft, the reciprocating motion of the old drawing machine is driven by a screw forward and reverse. The transmission of the grinding roller is realized by a long cylindrical transmission wheel, and the grinding wheel is also driven by the sun shaft. It is rarely used today.

The domestic hydraulic drawing machine is driven by a hydraulic oil cylinder and a plunger pull rod to drive the countertop. The grinding wheel is driven by a common motor with a V-belt. The grinding roller is also polished by a common motor. Flat belt reduction drive.

In the imported wire drawing machine, the reciprocating motion of the table is hydraulically driven, and the transmission of the polishing roller is realized by a soft connection through a pin-swing reducer. The machine guide rail lubrication fluid is supplied by a small oil pump, and a cutting fluid pump is used for cooling and dust removal when the grinding roller is polished.

4, the control switch of the polishing wire drawing machine

(1) Total control switch.
(2) Main oil pump switch.
(3) Grinder switch.
(4) Grinding roller polishing motor switch.
(5) Cooling liquid pump switch or vacuum cleaner switch.
(6) Guide rail oil pump switch.
(6) Light switch when drawing.

The above control switches are based on the introduction of machine tools. The domestic machine tool has no rail oil supply pump.

5. Specification and quality of grinding wheel

The grinding wheel for polishing is generally a flat grinding wheel. The diameter and thickness should be determined according to the specifications of the machine. Another type of bowl-shaped grinding wheel (for the introduction of Italian machine tools) is relatively rare, which is to use the bowl surface to grind the roller body.

The hardness of the grinding wheel is generally selected to be medium-soft. The grinding wheel of the medium-soft hardness is peeled off together with the iron scraps on the surface of the grinding roller during the grinding process, so that the surface of the grinding wheel is kept in a sharp state, thereby improving work efficiency.

The choice of grinding wheel particle size is generally 36-60. If the particle size is less than 36, the surface of the milled roller body is rough and cannot reach the accuracy of 7 or more. If the particle size is more than 60, the surface precision of the roller body can be improved, but the grinding is improved. Working hours are longer.

The grinding wheel is preferred to green silicon carbide, which has a slightly higher hardness than black silicon carbide and is suitable for chilled alloy cast iron and carbide tools.

The new grinding wheel must first check the appearance of obvious hard scars.

Check the surface of the grinding wheel and the adhesive uniformity. Pick up the grinding wheel and tap it with a hardwood stick to hear if the sound is crisp and consistent.

If it is best to make a dynamic balance test, if the deviation of weight loss is found to be large, it should be considered that there is a quality problem inside the grinding wheel that cannot be used.

In the unconditional balancing, simple static balance detection should also be performed, which is good for reducing the vibration of the machine tool and improving the precision of the surface of the roller.

6. Shaft and bearing of grinder

There are two types of bearings for polishing grinders, namely plain bearings and rolling bearings.

The shafts using sliding bearings are divided into two types, one is a cylindrical shaft, the bearing is made of tin bronze, which is the upper and lower parts of the split type, and needs to be scraped during installation. The bearing clearance is adjusted by using different thickness and thickness of the gasket. Method, the amount of gap is generally controlled within 0.03mm.

The other is a conical shaft. The outer part of the bearing is a cylindrical inner hole of cast iron with a conical copper sleeve. It needs to be ground during installation. The contact surface between the shaft and the sleeve should be more than 70%.

When using rolling bearings, the bearing is a single-row tapered roller with adjustable axial clearance. The amount of clearance can be measured at one end of the grinding wheel shaft with a dial gauge. The control is limited to 0.025mm. If it is less than this value, it will be in high speed operation. Destroy the oil film of the grease, the bearing will heat damage and affect normal operation.

7, the belt of the grinding wheel

The specifications of the grinding wheel drive belt are generally A-type belts, as well as narrow V3 type and jointless parallel ring-shaped nylon belts. If ordinary rubber transmission belts are used, the joints must be made trapezoidal and connected by adhesive.

Regardless of the type of transmission belt used, it should be carefully checked. For example, the bandwidth of the V-belt, the height of the belt, the joint length and the length, and the hardness should be uniform, so as to avoid the grinding wheel jumping during operation, thus affecting the surface precision of the grinding roller. .

8, grinding roller

The standard promulgated by the former Ministry of Commerce stipulates that the surface hardness of the roller body is from 66° to 78° Shore and the depth is 8 to 13% of the diameter of the roller.

When ordering the grinding roller, we should make clear requirements. For example, the hardness value of the toothed roller should be 78° Shore, which can extend the service life, reduce the number of replacements and reduce the roller loss.

The blasting roller used in the heart-grinding system should be selected from Shore 66°. Because of the low hardness value, it is suitable for irritating treatment, and can obtain ideal rough surface, which is also beneficial to the quality of the products in the production process.

9. Lifting tools for grinding and lowering machine tools

The lifting tools used in the upper and lower machine tools of the grinding roller should be selected according to local conditions. The size of the room for the drawing machine is different. The lifting methods are as follows.

1 Light rail single-girder crane is controlled by three motors, that is, driving, the lifting moves in parallel, and the lifting object moves up and down.
2 Single-track fixed type, using I-beam 16#~18# as the track. The hoist is mounted on the I-beam. The tool uses two motors, one for parallel operation and one for the crop body to move up and down.
3 hoisting electric hoist is divided into two types: wire rope winding type and chain type. It can be manually operated by chain type parallel movement, and the object is electric and can be used at will.

10. Precautions when grinding the upper and lower machine tools

When grinding the machine on the machine, the grinding wheel must be raised or retracted to prevent the grinding roller from colliding with the grinding wheel.

When drawing the grinding roller, the number of teeth to be pulled, the angle, the inclination and the number of teeth of the toothed ratchet and the number of teeth to be removed should be clarified and verified during the test run.

When the grinding roller is polished or drawn, the capping nut of the grinding roller bearing can not be pressed too tightly, and it is still not possible to twist.

When grinding the roller up and down the machine, it must be parked in place and the main switch closed to prevent accidents.

11. Inspection after the roller is mounted on the machine

The same flour mill may use different lengths of the roller body, and the diameter of the roller may also have a difference in thickness. Therefore, the roller must be properly adjusted to the center and position of the bearing to ensure the center of the roller body. The grinding wheel is coordinated, otherwise it is impossible to process a qualified grinding roller.

Check the center of the grinding roller. It can be used with a height micrometer or a scribe. The level of the grinding roller can be detected by using a dial gauge with a magnetic seat for paralleling the horizontal and horizontal sides.

12. Work that should be done before the machine is turned on.

Before the machine is turned on, observe whether there are any objects that should not be around the machine and up and down. Check the guide rails on the outer surface of the machine guide for dirt. Check whether the handle and the block are properly and firmly positioned.

After the above inspection, the main switch can be turned on to start the oil pump for a few minutes (ie, preheat). At this time, operate the slow handle to reciprocate the work surface. After stopping, check whether there is abnormality on the surface of the guide rail. If there is no abnormality, it can work normally.

If it is a buffing roller, the grinding wheel should be started first, but the operator should not stand opposite the grinding wheel to prevent accidents.

13. Dust removal problem when the roller is polished

When the roller is polished, a lot of sand dust and fine iron filings will be generated. It is necessary to take practical measures to eliminate it. Otherwise, it will not only pollute the environment, but also shorten the service life of the machine guide rail and transmission components.

Common dust elimination method

Under the grinding roller on the workbench, place a long water tank, inject water, and immerse the lower part of the roller into the water. Sand and fine iron filings from cutting can quickly fall into the sink.

Use the cutting fluid to eliminate dust, put a shallow tray under the roller body, which can receive sand dust and fine iron filings and recover the cutting fluid. The cutting fluid can be used repeatedly after filtering and sedimentation.

Using the vacuum method, a single fan is used to suck sand and iron scraps out of the room, and a centrifugal dust collector is collected centrally.

The most ideal dust removal is to use cutting fluid, which has less pollution and does not corrode the machine tool. The surface of the roller body that is polished with the cutting fluid is less likely to rust.

14, the size of the polished roller body

The reasons for the size of the roller body during the grinding of the roller are: the diameter of the roller shaft is changed by wear; the roller bearing support on the machine tool is displaced; the copper pad supporting the roller shaft is worn... and so on.

Therefore, when the grinding roller is initially ground, as long as the surface of the roller body is completely polished, the diameter of both ends of the roller body should be checked immediately. If inconsistencies are found, adjustments should be made in a timely manner. The test should be repeated several times, so that the diameter of the roller body is basically the same, that is, the error is not more than 0.03 mm in the basic length of the roller body.

The grinding roller thus polished can maintain good uniformity in the width of the top surface of the tooth and the depth of the groove, which is beneficial to the production process performance and the stability of long-term use.

15. When the roller is worn, the roller body appears to work.

The reason for the spotting when the shaft body is polished is that the grinding roller is installed in front of the machine tool, and the oil stain cleaning on the surface of the roller body is not completely cleaned; during the grinding process, the cooling cutting fluid used contains oil stain; when the polishing is close to completion, the inspection is completed. The operator touches the surface of the roller body with a hand with oil or perspiration; when the shaft diameter is refueled during the grinding process, the excess oil enters the cooling cutting fluid;

Spots appear on the surface of the roller body, and the surface of the grinding wheel can be corrected by a diamond trimming knife or a waste grinding wheel block.

16. Chamfering at both ends of the roller body

There are two purposes for chamfering the two ends of the roller body; one is to prevent the cutting edge and the cutting edge of the wire drawing knife from being damaged when the knife is fed; secondly, the end surface of the roller body is prevented from being damaged when the cutting amount is large, thereby causing a defect.

The chamfering at both ends of the roller body is preferably arc-shaped, the radius of the arc is at least R3, and the maximum is not more than R5, and the arc shape is advantageous for both feeding and cutting.

17. Cones at both ends of the roll body

The light roller requires the entire contact surface of the roller body to be straight during the process grinding process. The grinding material causes the roller body to generate a certain temperature, because the shaft at both ends of the roller body is solid, and the middle portion of the roller body is hollow, and the thermal expansion coefficients of the two are inconsistent, which causes the inconsistency of the rolling distance between the two rollers.

In order to meet the grinding requirements, both ends of the roller body are intentionally ground into a cone during polishing. The length of the cone at both ends is generally about 180 to 230 mm. There are two kinds of taper data provided by Buhler, namely: 40 to 45 μm; 30 to 35 μm after heart grinding c4. This is determined according to the principle of coarse and fine material before the material, the nature of the material and the grinding pressure, and the temperature of the grinding roller.

When the roller body is polished, the cylindricity and non-column of the roller body are first ensured, and the accuracy of the surface of the roller body is ensured to be 1.6 or more.

Before grinding the taper of the roller body, loosen the compression nut of the shaft diameter upper cover, place the dial gauge in one end of the roller body, and adjust the pointer of the dial gauge to start the desired taper. Then reach the grinding length requirement, that is, stop the measurement of the diameter change and achieve the design goal.

18, the roughness of the surface of the roller body

In the early 1980s, China announced a technical standard for grinding rolls. The surface roughness of the grinding roll body was 1.6. Since there are many manufacturers of grinding rolls, it is difficult to say whether they can reach this standard, let alone the surface precision of our flour mills when they are polished by old grinding rolls.

At present, there is a portable roughness inspection on the market. For example, if each flour mill purchases one, the surface roughness of the newly purchased grinding roller or the self-polishing grinding roller can be detected.

The quality of the surface roughness of the roller body has a direct relationship with the quality of the flour product and the rate of flour extraction. The finer the surface roughness of the roller body, the less the broken skin, the less fine powder into the flour, and the lower the flour ash. The use cycle of the grinding roller will be extended.

19, repair the tooth roller, replace the polishing with planing

When repairing used grinding rolls, it is not correct to use a grinding wheel to polish the grinding teeth without planing. Only polishing can ensure the cylindricity of the roller body, and can obtain better roughness accuracy, and ensure the width of the tooth top plane, thereby prolonging the service period, reducing the vibration of the mill and the noise of the workshop.

If a planing method is used, a polygonal body will appear on the surface of the roller body instead of a smooth cylinder. If the surface of the polygonal body is drawn, the top surface of the tooth will not be obtained, and the width of the top surface of the tooth is more difficult to ensure.

20. Heavy wire of the toothed roller

The used toothed rollers, especially one skin and two skins, have been worn for a long time, the surface of the roller body has worn out, and there is unevenness between the top of the tooth and the cylindricity is lost, and the plane of the top of the tooth disappears without a trace. Therefore, the surface of the roller body should be ground before the heavy wire to restore the original cylindricity and high quality surface roughness.

However, when polishing, as long as the tip of the roller body has been ground to a certain width, the weight can be started, which can reduce the loss of the diameter of the roller.

A toothed roll can generally be re-wired three times, and two rolls of heavy wire twice. In order to maintain the technical requirements of a certain pitch, the wire drawing cannot be repeated indefinitely to ensure the long-term stability of production.

21, wire drawing knife feeding method and number of loading

Domestic drawing machine (ie hydraulic drawing machine), the drawing knife of the machine is installed directly above the center of the roller body, and only one knife is installed.

The drawing machine is introduced. The wire drawing knife is mounted on the horizontal center side of the roller body. Two knives can be installed at the same time. One knife is in the center of the roller body and the other knife is below the center.

When pulling a toothed roller, two knives can be used at the same time to shorten the drawing time. In order to improve the accuracy of the large plane of the gully, it can be repeatedly pulled 2 or 3 times, which is beneficial to the production of grinding and product yield.

The installation of the wire drawing knife should be carried out in the middle of the roller body. It must not be carried out in the neutral position of the roller body. This is to prevent the wire drawing knife from protruding too long and colliding with the roller body.
22. A straight tooth that appears at the feed end when the toothed roller is drawn.

The reasons for the occurrence of straight teeth on the feed end roller body during drawing are as follows:

(1) The amount of retraction is insufficient, which can be solved by adjusting the position of the collision block.

Domestic wire drawing machine, the maximum length of the grinding roller is 1020mm. In the past, the length of the grinding roller used by us was 800mm. Now, with 1000mm long roller, it is not enough.

(2) The slope track and the slider are worn out in long-term use, resulting in excessive gap, which directly affects the amount of retraction and the buffer distance of the infeed. The gap should be trimmed in time to meet the shortage of retraction.

(3) In the size of the matching gap between the slider hole and the shaft, the size of the meshing gap between the worm and the worm wheel, the meshing clearance of the bevel gear, the matching clearance between the worm wheel hole and the shaft and the key, and the amount of clearance of other fittings, This is the reason for the occurrence of straight teeth at the feed end of the roller body.

23. When the toothed roller is drawn regularly, the uneven tooth pitch is uneven. When the wire is drawn, there is a phenomenon that the regular width of one tooth top is large. It should be checked from the following points.

1 Check if the pitch of the split ratchet is even, or if there are thick dirt on the individual teeth of the ratchet.
2 Check whether the meshing of the bevel gear on the worm is deviated, and whether the locking of the bevel gear hole with the shaft and the key is appropriate.
3 Check if the worm is bent, and check whether the tightness of the nut assembly at the lower end of the worm is moderate.
4 Check the tightness of the worm wheel hole and the shaft and the key.

After the above points are checked, they are indeed in a good state of technology and will not appear. If one item is not found or even assembled, the above problem will occur.

24, when the toothed roller is drawn, the last half of the tooth appears

Before the drawing of the grinding roller is polished, it is necessary to know what kind of tooth is used for the grinding roller. What is the number of teeth per centimeter, and the exact diameter of the roller body is calculated by grinding, as long as it is polished The diameter of the grinding roller eventually reaches this size, which will eliminate the phenomenon of half tooth.

Eliminating half of the teeth is conducive to the work of heavy wires in the future. If half teeth and heavy wires appear on the toothed rollers, a slight disorder will occur and one piece of chaotic teeth will not be used, and it will be forced to be re-polished, resulting in serious roller diameter. Loss, and unnecessary waste such as grinding wheels, electricity, and working hours.

25, the accuracy of the tooth root and the top of the tooth

To achieve high quality roughness accuracy, the root and the tooth plane must start with a ground wire cutter. I have worked as a turner. If the accuracy of the vehicle is higher than that on a machine with higher precision, the cutting edge of the turning tool must be trimmed to the above. The roughness of the edge of the wire drawing knife is trimmed to the above to ensure the roughness of the large plane of the groove can reach the above, otherwise it is empty talk.

When grinding the wire cutter, it is best to carry it on a special simple grinder. The utility model has the advantages that the drawing knife can be pressed on a platform capable of resting on the mold, the platform can be longitudinally oscillated, the angle can be adjusted, and the retracting knife can be moved back and forth to ensure the angle of the grinding is accurate; the cutting edge of the drawing knife is ground on the end surface of the grinding wheel. High surface precision. It is far more reliable than the hand-held wire drawing knife on the outer surface of the grinding wheel.

After the wire drawing knife is ground, the cutting edge part needs to be trimmed with fine stone, and the tip of the angle is trimmed into a suitable arc. This is to meet the needs of the tooth root part, so that the wire drawing knife is ground. A higher quality roughness can be obtained on the large plane of the groove. Only in this way, when the grinding roller is put into use, a large and thin grinding effect of the bran can be obtained. Thereby improving the quality of the flour, reducing the ash content of the flour and the flour content of the bran.

26, the width of the tooth tip plane

The author had done drawing work in the 1950s. Before the mid-1980s, it was said that no one had proposed a plane with a certain width for the tooth top of the tooth roll. Although the technical management personnel paid great attention to the quality of the brush roll, they did not know the tooth. Technical data for top plane width.

After the 1980s, the introduction of milling equipment was used, and the technical requirements of the grinding roller were seen from the process drawing. For example, the Swiss Buhler company has a width of 0.2 mm from the top to the top of the three teeth and 0.1 mm after the four skins. The Italian skin is 0.3mm, and later it is 0.25, 0.2, 0.15mm, etc., which shows the difference in technical requirements between the two companies in the same process.

The plane of the tooth tip of the tooth roll leaves a certain width to ensure the cylindricity of the roller body, reduce the damage of the bran during the production and grinding process, and reduce the vibration and noise during the operation of the mill.

27, the wire drawing machine table appears creep during operation

During the movement of the machine tool, the cause of the creep phenomenon on the work surface is caused by the gas generated in the hydraulic pipeline. The following measures can be taken to eliminate it.

1 Unscrew the oil drain on the hydraulic line to discharge the gas and also discharge some oil. The oil pump should be turned off when exhausting.
2 Check if the amount of oil in the oil storage tank is sufficient, and the oil quantity is also a cause of gas generation in the pipeline.

When refueling, apply 120 mesh copper wire cloth and then add it to prevent impurities from entering and damage the oil pump and other accessories.

28, the wire drawing machine table rises during operation

The work surface elevation during drawing only occurs on machine tools with inclined slope rails.

The reason for causing the work surface to rise during the movement is very simple. The roller is mounted on the bearing housing of the machine tool to cover the upper cover. When the nut is tightened, the pressure is too tight, causing the grinding roller to twist and force the work surface to rise. Phenomenon, as long as the compression nut is loosened to eliminate.

If the above method is invalid, it can be checked whether the sliding plate of the indexing mechanism worm up and down is too tight, which is also a reason for the elevation of the work surface.

29. Polishing the roller body with a special cylindrical grinding machine

The cylindrical grinding machine is a machine tool specially used for grinding cylinders. Its precision is higher than the precision of our domestic polishing machine. In recent years, the flour mill has been used to grind the roller body. The grinding roller processed by the cylindrical grinding machine can obtain high quality rough precision, cylindricity and conicality.

When the roller is mounted on the cylindrical grinding machine, the roller body is supported by a pair of heads and tails. After the grinding roller is fixed and fixed, the dial gauge is used to measure the radial runout of the shaft at both ends of the grinding roller. If the standard tolerance is exceeded, the tip center hole should be removed to ensure the concentricity of the roller shaft and the roller body.

The high precision of the surface of the roller body is beneficial to prolonging the service life of the toothed roller and improving the product quality; the hearth polishing roller is then subjected to sand blasting to make the surface roughness of the roller body more uniform.

30, special sand blasting machine

The sand blasting machine is a special equipment for processing the light roller of the heart-grinding system to roughen the surface of the roller body. It can process the roller of different lengths and different diameters of the roller body to obtain the most ideal rough surface of the roller body.

Sand blasting is the use of a compressed air stream to spray the polyhedral grit sand into the surface of the roller body to make it lose its luster and form a uniform rough surface.

The special sand blasting machine is the first to be found in the Swiss company Buhler. At present, there are products in China, and the effect is basically the same. If there is a difference, it is the quality of the grit and the pressure of the blowing pressure. It takes about 3 to 4 kg of corundum to process one grinding roller.

This special machine has good sealing performance and can also recover used silicon carbide. After screening, the coarse particles are mixed with new sand.

31, substitute sand blasting machine

The grinding roller is supported on the workbench of the C630 lathe, and the nozzle is mounted on the tool holder of the large pallet of the lathe for reciprocating motion. A small air compressor is used as a gas source to spray the gold steel sand onto the surface of the roller body, which is usually sprayed several times to meet the basic requirements of roughening.

This kind of sand blasting is carried out in the machine repair workshop. During the sand blasting process, although there is a brush-like dust cover around the blasting nozzle mouth, the crushed gold slag powder is still splashing everywhere and harming other machine tools, gold and steel. The sand recovery rate is very low, and it is necessary to use 5 to 6 kg of gold steel sand for one grinding roller.

There are 3 kinds of gold steel sand nozzle materials, (1) industrial ceramics; (2) wear-resistant rubber; (3) wear-resistant metal steel, some flour mills use ordinary carbon steel self-made nozzles, low cost but short life, with 1 It is also cost-effective to scrap.

32. Roller sand press

The roller sanding machine can be made according to the actual length of the grinding roller of the factory. Use channel steel or rectangular steel pipe to form a frame, use 4 roller bearing boxes, 2 fixed and 2 movable, and then adjust the rolling distance with two screws. It is driven by a 1:11 geared motor and 2 sheaves. The fast and slow roller drive gear can utilize the heart grinding gear.

Before the roller is pressed, the surface of the roller should be coated with oil to stick the gold sand. The gold steel sand can be directly sprinkled between the two rolls by hand holding the funnel, and it is evenly distributed when sanding. After running for 3 to 5 minutes, the surface roughness of the roller body was observed. Treat 1 pair of rolls with sand for 3kg or more.

1 pair of grinding rolls processed by sand pressing method, the surface roughness of the fast and slow roll body has obvious difference. When used on the grinding machine, the rough surface should be mounted on the fast roll, and the roughness is slightly poor. On the slow roll, there is no bad phenomenon in the grinding efficiency of the production process.

Using this method, the simple sand blasting machine is less costly and pollution-free than the C630 lathe. It is the used old grinding roller, the roller without obvious defects, and the sand is directly pressed without polishing, and the effect is also quite good.

33, mill sand press

China's vast flour mills are widely distributed. In the absence of a dedicated, alternative sandblasting machine and a roller compactor, the problem of smoothing of the roller can also be solved on the mill. It is to use a reducer to drive the fast roller to control the speed at 60 rpm. . However, some parts of the picker and the grinding roller should be removed. Applying oil to the surface of the roller body and starting the reducer, the steel grit can be sprinkled into the grinding zone for a few minutes, and the surface of the roller body can obtain a satisfactory rough surface.

Although this simple method is good, it is time-consuming and laborious to remove the oil stains on the surface of the roller body and the gold steel sand afterwards, and to clean the cones. The cleaning should be carried out carefully and carefully, and one grain of sand should never be left in the machine.

34, grinding roller polishing, wire drawing, sand blasting testing equipment

(1) Micrometer, detecting the outer diameter and shaft diameter of the roller body.
(2) Portable roughness meter to detect the surface roughness value after grinding and sandblasting.
(3) Universal angle ruler and angle model to detect the angle after the tool is ground.
The sample is tested to maintain the center of the wire cutter tip.
(4) For external use, the cylindricity, flatness and radial runout value of the roller body are detected.
(5) Diamond plastic knives, special tools for dressing grinding wheels.
(6) The calculator is a tool for calculating the wire elimination of the half tooth.
(7) Oil stone, trimming the edge of the wire drawing knife and the arc of the corner of the angle, and improving the roughness of the large plane of the groove.
(8) Simple micrometer to measure the width of the top surface of the tooth.
(9) Portable hardness tester, which detects the surface hardness value of the roller body and can detect the hardness value after the diameter of the roller body becomes smaller.
(10) Height vernier caliper, which can measure the grinding roller on the same center line on the machine tool and the center of the indexing head.

35. Handling and storage of grinding rolls

After the repair, the roller roller, the tooth roller, and the blasted roller are processed products, which should be carefully taken care of during handling.

After the repaired grinding roller is removed from the machine tool, it is best not to touch the ground. It should be placed on the wooden board or square bar, and the roller and the roller should not collide. The wooden block is used to separate it. Place it on a herringbone frame or on a single row of shelves against the wall (see Figure 1). This will reduce the footprint.

Figure 1 Schematic diagram of the roller storage rack

When storing the grinding roller for a long time, the surface of the roller should be coated with anti-rust oil to prevent the surface of the roller from rust and corrosion.

When the roller is removed from the storage rack, it should be placed directly on the handling cart. It is absolutely not allowed to drag or roll on the concrete floor to prevent damage to the surface precision of the roller.