What maintenance is most suitable for a three-roll plate bending machine?

Suitable maintenance oils for three-roll plate bending machines + complete graded maintenance plan

Three-roll plate bending machines are divided into mechanical three-roll and hydraulic three-roll types. First, we discuss the suitable oils for each part (general-purpose, cost-effective options for workshops), then we provide detailed daily/weekly/monthly/quarterly/annual maintenance guidelines, covering rust prevention, cleaning, precision, and hydraulic system maintenance.

I. Specialized maintenance greases for each part (applicable and readily available on the market)

1. Rolling bearings, roller journals, grease cups and nozzles (upper and lower roller bearing seats)

Selection: 0#/1# general-purpose lithium-based grease (dropping point ≥180℃)

- For heavy-duty, high-temperature workshops, use extreme pressure lithium-based grease/molybdenum disulfide lithium-based grease, which is impact-resistant and water-resistant;

- Filling method: Use a grease gun to apply grease until there is slight overflow at both ends of the shaft;

- Cycle: Check the grease cup level every shift and replenish grease every 200 hours.

2. Lifting screw, sliding guide rail, and tilting hinge sliding surface:

46# mechanical lubricating oil (medium-load industrial machinery oil)

- Advantages: Good fluidity, penetrates screw threads, prevents dry grinding and seizing;

- Operation: Apply with a brush/drip from an oil can every shift, remove metal filings before applying oil.

3. Main reducer, worm gear, gearbox (core transmission):

Medium-load industrial gear oil 320# (mainstream general use)

- Use 460# for two-shift heavy-duty and high-temperature workshops;

- Standard: Oil level should be between the upper and lower marks on the oil gauge. Replace immediately if the oil turns black or contains metal filings;

- Replacement cycle: Replace every 6 months for continuous production, and every 12 months for single-shift production.

4. Hydraulic three-roll plate bending machine oil station hydraulic oil:

46# anti-wear hydraulic oil (year-round use)

- 32# can be selected for low-temperature workshops in winter, and 68# for high-temperature workshops in summer;

- Matching: Clean the hydraulic filter monthly and replace the filter every six months; completely replace the hydraulic oil once a year.

5. Rust Prevention and Maintenance for Exposed Rollers and Unpainted Metal Surfaces of the Machine Body: Thin-layer rust-preventive oil/dehydrated rust-preventive oil

- Apply a thin layer after cleaning iron filings at the end of the workday. For stainless steel rolling applications, this prevents rust spots from scratching the roller surface.

- For long-term shutdowns: Wrap the entire roller with oil paper and seal with rust-preventive oil.

6. Open Gear Transmission (Exposed Large Gear): Extreme pressure lithium-based grease. Apply monthly by removing the protective cover and rotating the machine around the entire gear shaft to evenly cover the gear surface.

II. Graded Maintenance Details (Practical Implementation, Divided into Four Levels)

(I) Daily Pre-shift/Post-shift Maintenance (Mandatory for Operators, Basic Maintenance)

1. Lubrication

Check and replenish all oil cups; apply 46# machine oil to the lead screw and guide rails; apply a small amount of grease to the roller bearings using an oil gun.

2. Cleaning

Clean the surfaces of the three working rollers, removing iron filings, welding slag, and burrs. Prevent hard objects from directly impacting the roller surface; clean the machine body and base of metal dust.

3. Inspection

For hydraulic presses, check the hydraulic station oil level and for leaks; listen for abnormal noises from the motor and gearbox; check the foundation bolts and bearing seats for looseness; perform two unloaded rotations of the forward and reverse rollers to confirm there is no jamming.

4. Finishing Rust Prevention

Stop the machine, wipe the rollers clean, and apply a thin layer of rust-preventive oil; disconnect the power supply and clean up any debris on the ground.

(II) Weekly Maintenance (1 time/week)

1. Fully fill all bearings with grease nipples;

2. Check the coupling's elastic buffer pads for cracks or aging;

3. Clean dust from the hydraulic station cooling fins and oil tank surface;

4. Tighten all bolts on the machine body, tilting support, and lead screw nuts;

5. Check the limit switches and foot switches for proper wiring.

(III) Monthly Deep Maintenance (Every 30 Days)

1. Remove the gear protective cover, apply lithium-based grease to the open gears, and clean the metal shavings between the teeth;

2. Hydraulic System: Clean the suction/return oil filter element, and check the hydraulic oil for emulsification and impurities;

3. Check the roller surface for dents and scratches; polish minor damage with an oilstone;

4. Check the bearing temperature rise and for abnormal noises; report any excessive clearance immediately;

5. Apply anti-rust oil to all exposed unpainted parts of the machine.

(IV) Quarterly/Annual Overhaul Maintenance

1. Quarterly (3 Months)

Remove the lifting screw cover, thoroughly clean the threaded metal shavings, and reapply lubricating oil evenly; check the wear of the tilting mechanism pins.

2. Annual Maintenance (12 Months, Major Overhaul)

- Drain the old gear oil from the reducer, clean the gearbox, and add new 320# gear oil;

- Replace all hydraulic oil and filter elements in the hydraulic press, and clean the oil tank;

- Disassemble the roller bearings, clean and replace the lubricating grease, and replace bearings with excessive wear;

- Calibrate the parallelism and levelness of the three rollers to ensure rolling accuracy;

- Remove rust and touch up the paint on the entire machine, replace all oil seals and sealing rings, and prevent oil leakage.

III. Key Maintenance Points for Hydraulic Three-Roll Plate Rolling Machines

1. Oil Temperature Control: Normal range 40-55℃. If it exceeds 65℃, stop the machine to cool down and check if the cooler fins are blocked;

2. Prevent Water Ingress: Ensure the oil tank is properly sealed to prevent rainwater and cutting fluid from mixing and causing hydraulic oil emulsification;

3. Hydraulic Cylinder Piston Rod: Wipe it down every shift and apply a thin layer of hydraulic oil to prevent rust and avoid metal shavings damaging the piston rod. IV. High-Precision Roller Maintenance (Directly Determines Rolling Quality)

1. Do not directly roll steel plates with weld slag or burrs to avoid indentations on the roller surface;

2. Clean iron filings from the roller surface before processing stainless steel or aluminum plates to prevent foreign metals from damaging the workpiece;

3. For long-term non-use: Wipe the roller clean with anti-rust oil, place it under cork for insulation, and avoid direct contact with hard surfaces.

V. Maintenance Taboos (Behaviors that Significantly Shorten Equipment Lifespan)

1. Mixing different types of grease and gear oil will cause sludge to form and block the oil passages;

2. Adding oil without changing it will result in long-term wear of bearings and gears due to metal debris in the oil;

3. Dry grinding of the lead screw and guide rail due to insufficient lubrication will cause jamming and lifting difficulties;

4. Continuing to use hydraulic oil that has become emulsified with water will cause valve blockage and unstable pressure;

5. Long-term shutdown without roller rotation or rust prevention will cause the roller and bearings to rust and seize;

6. Overloading the rolling plate and forcibly pressing it down will accelerate the damage of the lead screw and bearings due to overload.

Quick Selection and Maintenance Oil Chart

| Lubrication Points | Compatible Oils | Replacement/Addition Cycle |

|--------|---------|------------|

| Roller Bearings, Grease Nipples | 0# Extreme Pressure Lithium-Based Grease | Top up every shift, complete grease change monthly |

| Lifting Screws, Sliding Guides | 46# Machine Oil | Drip every shift |

| Gearboxes, Worm Gearboxes | 320# Medium Load Gear Oil | Replace every 6-12 months |

| Hydraulic Stations (Hydraulic Presses) | 46# Anti-Wear Hydraulic Oil | Replace annually, clean filter monthly |

| Exposed Roller Rust Prevention | Dehydrating Rust Inhibitor | Apply thinly after each shift |

| Open Exposed Gears | Molybdenum Disulfide Lithium-Based Grease | Apply monthly |