Making —English Translation of the Bafang Three-roll Mill Manual

Notice from Drapak:
Use this manual at your own risk. There could easily be translation errors in this document. I scanned the original Chinese instruction booklet that came with my three-roll mill. Then I put the images through optical character recognition. The resulting Chinese was put into Google Translate, and then lightly cleaned up by myself. So expect plenty of opportunities for mistakes to happen. Mind you, this is better than nothing!

Original scans: Cover, Pages: 1 2 3 4 5 6 7 8 9 Machine diagrams: S150 S260 S315 SM405 SM405 extended

BAFANG - S Series Three-roll Mill

Changzhou Caibao Machinery Co., Ltd.
Changzhou Wujin Bafang Machinery Factory

Address: South of Gujiabu Bridge, Hengshan Bridge Town, Wujin, Changzhou City, Jiangsu Province

Text: 0519-88601535

True: 0519-88606310

Mobile: (0) 13906118370



In order for you to better understand and operate the device correctly, we have carefully compiled this instruction manual, please read it carefully before you start the device.

Read it, and place it close to the equipment. At the same time, the operator must follow the items and operating methods listed in the manual to ensure small, medium, and large-scale production is successful.

1. Safety Information

You should always follow the following basic safety precautions to reduce the risk of damage to the machine and personal injury:

  1. Read and understand all instructions.
  2. Use common sense when using mechanical and electronic equipment.
  3. Follow all warnings and instructions in the materials attached to the machine.
  4. If the operation manual conflicts with the safety information, please pay attention to the safety information. If you are missing the operating instructions, please contact a sales representative or service for help.
  5. Before cleaning the machine, please turn off the power switch of the machine and unplug it. Do not use corrosive liquid and aerosol cleaners to clean the rollers.
  6. This machine is not suitable for grinding corrosive or hard materials (except for stainless steel rolls and non-metal rolls).
  7. After processing water-based materials or storing the machine, please apply anti-rust oil or anti-rust grease on the surface of the rollers.
  8. You must operate the machine with the water cooling system running, except for heating type machines.
  9. Do not squeeze or bend the wires of the machine, the electrical box, nor the emergency stop switch wire - otherwise it will cause a fire or electric shock.
  10. Do not pierce or penetrate the machine’s outer casing or chassis. This could contact dangerous voltage, fuel tanks, water tanks, leading to fire, electric shock, damage to the transmission gears, blockage of the cooling system, or roller damage.
  11. In order to avoid accidents, please do not disassemble or put pressure on the machine. If you want to repair it, please contact professional technical service personnel to open or disassemble the machine covers. Disassembly can expose you to dangerous voltages or other dangers. Incorrect reassembly can cause danger when the equipment is used later.
  12. Before using the S65, S200, S315, SM405 and SM405 extended three-roll mills, please inject #3 lithium base grease into the gearbox, and the grease nipples. (Drapak’s note: I could not find #3 lithium grease in North America, so I used normal #2 lithium grease. I also cleaned out the existing grease on the gears and in the two bearing covers before using it because there was some metal dust still in the machine. Yes, this contradicts the advice given above. but a tidy machine is a happy machine!)
    After running the machine normally for 1 week, inject an appropriate amount of lithium-based grease. Before using S100 and S150, add #68 hyperbolic gear oil up to the oil mark position. After 1 month of standing unused, inject an appropriate amount of #3 lithium-based grease into the grease nipples.
  13. There are clear markings on the inlet and outlet pipes. Don't connect them incorrectly. The outlet water must flow downwards. (Drapak’s note: on my S65, the inlet had a 10mm (⅜”) hose barb, and the outlet had a 20mm (¾”) hose barb.)
  14. Place the machine flat and level. Turn on the power, pay attention to the direction of rotation and ensure that the discharge roller is running outward correctly.
  15. DO NOT run the machine dry without material in the rollers. This will cause serious damage to the surface of the rollers!

2. Uses and performance characteristics

The S series three-roll grinder is mainly used to grind various paints, inks, inks, oil paints, coatings, adhesives, food, for cosmetics and other fine-grained materials. Materials that are not suitable for grinding are those that would cause corrosion of the rollers. In recent years, cable materials, artificial leather, plastic are also used. There has also been a great development in the production of soap and aluminum core materials. This machine has become the main processor of fine materials for manufacturing these.


The three-roller of this machine uses a chilled carbide centrifugally-cast roller. The thickness of the chilled alloy layer is between 15 ~ 35 mm. The surface hardness is between HS68 ~ 72. The three rollers are manufactured by using a special medium-height grinder to precisely grind the rollers. The effective working surface of the three-roller is slightly convex. The three-roll mill grinds the fine material using the stiffness of the roll and thermal expansion and contraction. The rollers automatically compensate for this, improving the service life of the rollers, and at the same time improving the grinding efficiency and fineness of the material. In general, materials should be processed two or three times through the mill, depending on the original fineness and toughness of the material. After grinding several times, the fineness required for the product will be reached (usually about 3 ~ 18 microns, measured by a fineness plate).

3. Main technical parameters

Model S65 S100 S150 S200 S260 S315 SM405  SM405 Extended 
Roller diameter (mm) 65 100 150 200 260 315 405 405
Roller length (mm) 125 250 300 500 695 755 810 1000
Motor power (kW) 0.75 1.1 2.2 4.0 7.5 11 15 22
Roller speed ratios  1:2.8:7.8   1:2.6:6.6   1:2.5:6   1:2.8:8.1   1:2.8:8.1   1:2.8:8.1   1:3:9   1:3:9 
Weight (kg) 60 300 400 700 2000 2800 5000 5200

4. Working principle of the three-roll mill

When working, you can seperately adjust the gap between the the middle roller and the fast and slow rollers to suit the fineness requirements you need. Leave at least 0.1 mm between the rollers to avoid friction damage.

Start the machine, adding material between the two baffles between the middle roller and the slow roller.

Adjust the roller gaps for precision 1-2 times at the start of the processing run.

While working, the material to be processed is squeezed by the surface of the middle and slow rollers and is brought through friction to the middle and fast rollers for further grinding.

The processed material is scraped off by the discharge apron knife close to the surface of the fast roller and the material can flow into a container.

Schematic diagram of the working principles of a three-roll mill

Arrows show the rotating direction of the rollers

5. Structure of the machine

This machine mainly has a chassis, upper covers, roller sleeves, bearing seat, baffle plates, discharge hopper, cooling devices, gears, pulleys, etc.

The two guide rails of the chassis support six bearing seats of the fast, middle and slow rollers. Among them, the middle roller is fixed solidly to the base, while the fast roller and slow roller bearing seats move along on the two guide rails of the chassis.

The hand wheels adjust the screw and compression spring back and forth to determine the roller gaps and the final fineness of the material to be processed.

Schematic diagram of machine structure

5.1 Transmission system

The transmission system is driven by the motor in the chassis to the drive shaft through a V-belt. The fast roller gear is driven by the drive shaft gear, and then the fast roller gear is driven by the fast roller gear. The other gear on the roller supports the middle roller gear, and finally the slow roller gear is driven by the other gear of the middle roller, completing the transmission system.

5.2 Roller Simple Parts

The roller sleeve is made of chilled alloy centrifugal casting (S65/100 type is Gr15 material), and the shaft heads at both ends are assembled with an interference fit, making them sturdy and stable.

5.3 Feeding parts

The infeed is mainly composed of two baffle plates and their adjustment brackets. They are installed on the working arcs at both ends of the slow and middle rolls. These baffles prevent the material from overflowing the ends of the rollers. The brackets anchor the baffle plates and adjust the contacting arc of the baffle plates on the roller. The baffles do not affect the material while they contact the surfaces of the rollers. The baffles are able to be removed for cleaning.

5.4 Cooling components

Heat has to be removed from rollers so that it does not affect the gap between them. Heat is generated by the material being squeezed and rubbed between the roller's working surfaces. The water coolant pipe is installed the back of the machine. You should adjust the flow of water, so that the rollers can work properly. Maintaining the best alignment during of rollers during use improves the fineness and efficiency of grinding. The water flows out of the rollers and can be stored in a reservoir or recycled.

5.5 Adjustments

The machine mainly has four handwheels to rotate, adjusting the spacing between the rollers. This controls the fineness of the material to be ground. There is a spring between the handwheel screws and the bearing seats that is compressed, eliminating backlash.

5.6 Discharge parts

The discharge apron is installed on a bracket. The mouth of the discharg apron is equipped with a scraper blade. Use the screws to adjust the pressure on the outfeed roller, making the blade close to the surface of the fast roller. Make sure the position of the knife edge is slightly higher than the center of the roller, so that it is easy to scrape the material onto the apron.

6. Installation and commissioning

6.1 Installation

First make a concrete foundation according to the drawing of your selected model. Leave square holes in the concrete for the anchor bolts, and wait until the concrete is close to dry. After drying, lift the machine off the ground, then insert the anchor bolts into the screw holes of the machine. Align the bolt with the square holes in the concrete, and slowly lower the machine on the foundation, using a level to make vertical and horizontal corrections. Finally, pour cement and finish the surface layer of the foundation. After the cement is completely dry, tighten the screws. Note: The machine must be installed with a grounding wire to avoid accidental electric shock. Put the machine flat on the anti-vibration pad without using anchor screws.

6.2 Test run

First, thoroughly remove all anti-corrosion grease and debris attached to the machine and do all the preparations listed above before the test run. To avoid hidden dangers that may affect the test run, adjust the baffle plates and the discharge apron so they are separate from the surface of the rollers before testing.

Run the machine, making sure the temperature rise of the bearings are normal, the transmission gear mesh well, there are no impact sounds, and the rotation of parts are normal, etc. Turn on the cooling water, adjust the fast and slow rollers to the appropriate gap with the middle roller, and put in a small amount of a fine, dark material to process. Aim for a flat surface of material on the rollers by slowly adjusting the gap. Generally speaking, the color of the surface of the rollers will appears uniform or slightly lighter. After measuring the fineness of the material and checking that everything is normal, the mill can be put into normal production.

7. Machine operation

After the machine has been set up and run empty, and you have confirmed that there is no fault, pay attention to the following:

7.1 Before work

Check whether the surface of the roller is clean, whether there is enough grease to lubricate the parts, whether the fast and slow rollers are loose from the middle roller, the discharge scraper is normal, and so on.

7.2 Using the machine

7.2.1 Turn on the water cooling pump, and after starting the motor, slowly adjust the fast and slow rollers to the correct position for the material to be processed. For soap and aluminum core materials, generally adjust the gap between the fast and slow rollers and the middle roller to about 0.5mm. Then add the materials to be processed, and then make a precise and meticulous adjustment according to the fineness you need. When the material to be processed is a high-colored substance (such as oil, lacquer, ink, paint, pigment, etc.), generally speaking, the surface color of the rollers will be the same if the gaps are adjusted correctly. After the roller is adjusted, put the discharge apron on the item.

7.2.2 The grinding of the material happens mostly from the pressure and friction between the rollers. The roller speed also plays a role in bringing out the finely ground materials. Because the rotation speed of the three rollers is different, so is their linear speed and the surface of the roller could be badly abraded if they touch. The damage would also be different for each roller. Therefore, never have the rollers touch without having material to process.

7.2.3 If the middle of the roll is thinner and the ends are thicker when working, you can increase the cooling water flow to adjust. After the roller expands from heat due to surface friction, it will become flat after a short period of time. Appropriately reduce the flow of cooling water. In short, adjust the flow of water according to the actual situation. It must be noted running the machine without cooling water is absolutely NOT allowed, because of the risk of damage to the rollers. When the heat on the surface of the roller rises to a certain level, the surface of the roller is peeled off or badly deformed, resulting in permanent damage.

7.2.4 Avoid grinding corrosive materials (except stainless steel rollers, ceramic rollers, and granite rollers).

7.2.5 Pay attention to the adjustment of the gaps between the rollers at all times. Due to the thermal expansion of the rollers, it is easy for the gap to change, and the rollers could swell, and even stall or break the motor, causing an accident.

7.2.6 The baffle plates should not be pressed too tightly. Add lubricant in the contact arc at any time. Depending on the run, the baffle can be adjusted along the length of the working surface of the roller. If the two ends of the roller get hot from contact with the baffles, use paper shims placed between the baffle supports and the upper cover in order to reduce the amount of contact. Normally, the friction between the plate and the rollers reduces the temperature at both ends of the rollers.

7.2.7 Note that during normal operation, the temperature rise of the bearing shall not exceed 45 degrees.

7.3 After work

First loosen the contact between the scraper blade on the baffle plates and the roller, and then relax the roller, and then clean and use rust preventative on the equipment parts one by one.

8. Lubrication and maintenance

8.1 Open the oil cap of the gearbox, and add grease or oil as appropriate to lubricate the mating surfaces of the gears.

8.2 The bearing housing has been filled with lubricating grease before leaving the factory. It is not necessary to refill it before using it. After 120 hours of use, lubricate the machine again through the oil cup or grease nipples.

8.3 The drive shaft must be lubricated through the grease nipple every time it is used.

8.4 The adjusting screws, the bearing seat of the fast and slow rollers, and the two guide rails should be filled with lubricating oil at all times to avoid wear and gouges.

8.5 After using the machine continuously for half a year, conduct a major overhaul, removing and washing the movable parts. Replace with clean lubricating grease, and carefully check the oil circuit for obstruction. Then make any corrections needed.

8.6 If the roller is stuck in the middle, peeling off parts of the surface or if it deformed, it must be taken out of service. The roller will have to be repaired and reground.

8.7 After being reground too many times, the diameter of the roller will become smaller than its nominal roller diameter, resulting in a gap between the gear transmission. Too large a gap between the rollers makes it impossible to grind fine materials. If this happens, the gear must be corrected to reduce its pitch diameter or you can simply replace the roller.

8.8 The cutting edge of the discharge apron blade should be carefully ground before installation. It should be polished and smooth, with no sharp burrs or cracks allowed. After using it for a short time, you can loosen the screw of the pressing blade, move it forward and use it again. After the blade is used up, pay attention when adding a new blade to make sure that the hardness of the selected blade material is between 30HRC ~ 40HRC.

8.9 When the machine will be shut down for a long time, the surface of the rollers and related parts should be coated with anti-corrosion grease to avoid pitting and rust on the surface of the rollers, which would make them unusable. Before unpacking and using the machine again, carry out a major overhaul of the machine to avoid accidents.

8.10 If cooling water flows into the machine, the cooling water pressure is too high. Reduce the water inlet and loosen the water bolt at the same time. If water accumulates in the gearbox, enlarge the water outlet pipe.

9. Maintenance and disassembly procedures

9.1 Disassembly and Assembly of Roller Bearings

9.1.1 First loosen the adjustment handwheels, and take off the belt slip and the upper cover.

9.1.2 Loosen the bolts of the discharge apron bracket. Then loosen the bolt of the discharge apron and take it out.

9.1.3 Loosen the upper cover bolts and remove the upper cover from the internal cooling water pipes.

9.1.4 Use a three-jaw puller to remove the gears from the roller shafts. Loosen the roller shaft seat pressure plates and take out the washers. Use a three-jaw puller to remove the bearing seat from the roll shaft.

9.1.5 Use a sleeve of pipe or tubing to remove the bearing from the bearing housing. Note: When assembling the bearing and the bearing seat to the roller shaft, the outer ring of the bearing should be inserted evenly inline with the bearing seat. If this is too much, use a three-jaw puller to pull the bearing seat out of the roll shaft a little bit.

9.2 Disassembly and assembly of the drive shaft bearings

9.2.1 First loosen and remove the adjusting handwheels and the roller. Then remove the belt cover and upper covers.

9.2.2 Loosen the bolt of the stopper bracket to take out the stopper, amd loosen the bolt of the discharge apron to take it out.

9.2.3 Loosen the upper cover bolts and remove the upper cover. Then remove the plastic pipes on the cooling pipes and loosen the cooling pipe brackets to take out the rollers and internal cooling water pipes.

9.2.4 The rollers should be removed in the order from slow, medium, to fast.

9.2.5 Remove the belt and press out the upper pulley.

9.2.6 Loosen the bearing plate at both ends of the drive shaft and take out the bushing ring.

9.2.7 From the outside of the machine, use a sleeve to hold the drive shaft bearing and knock out the drive bearing.

9.2.8 Use a puller to hold the drive shaft and pull out the bearing.

10. Common faults and troubleshooting

10.1 Surface damage on the roller

Check the roller surfaces before running for damage due to improper operation, running without material, or foreign matter falling into the rollers.

Repair the surface damage of the roller sleeve. First, cut off the power supply of the equipment, open the cover, and remove all the connecting parts on the bearing housing (mark the dismantled parts). Take out the damaged roller and place it on a wooden frame, disassemble and press out the bearing seat. Refer to 9.1.1-9.1.5 for the dismantling method. Then, the surface of the roll should be polished with the position of the bearing installed on the shaft head of the roll as a reference.

10.2 Safety bolt breaks

The equipment should be stopped quickly in the case of improper operation, poor roll adjustment, or due to foreign matter falling into the rollers while working. If this happens, check the equipment carefully. To replace the safety bolt, refer to the instructions in the complete device diagram.

10.3 Leakage on both sides of the roll

After a lot of use, the roller surface wears the bronze end baffles, which increases the gap between the baffle and the rollers, causing material leakage. You can eliminate this by adjusting the positioning bolt on the end baffle support.

11. Packing list