Installation, Maintenance, and Troubleshooting Guide for Bonfiglioli 300/300M Series Gearboxes



Bonfiglioli 300/300M series gearboxes: installation, maintenance, and troubleshooting

In heavy industry transmission systems, the installation quality and maintenance level of gearboxes directly determine the operational reliability and service life of the equipment. The Bonfiglioli 300/300M series modular planetary gearboxes are widely used in mining, port, metallurgy and other fields due to their high power density and flexible configuration. However, even the highest quality equipment can still lead to early failure if installed improperly or maintained improperly. This article is based on Bonfiglioli's official "Installation, Operation, and Maintenance Manual for 300/300M Series", providing on-site engineers with full process technical guidance from unboxing inspection to daily maintenance, with a focus on special operating requirements in ATEX explosion-proof environments.

Open box inspection and safe handling

1. Arrival inspection

After receiving the goods, first check whether the shipping list matches the order information, and inspect the gearbox for any transportation damage. If any discrepancies or damages are found, the Bonfiglioli distributor should be contacted immediately. Packaging materials must be disposed of in accordance with local environmental regulations.

2. Lifting and handling

The weight and external dimensions of the gearbox may make manual handling impractical, and appropriate mechanical lifting equipment must be used.

Selection of lifting points: The manual provides detailed lifting diagrams for different series and configurations. For gearboxes that have already been assembled with motors, it is strictly prohibited to use the eyebolts on the motor housing for lifting unless explicitly marked as allowed.

Maximum tilt angle: During the lifting process, the swing of the load in any direction shall not exceed 15 °. If the angle exceeds this, the lifting device should be stopped and readjusted.

Requirements for lifting equipment: Use certified lifting eye bolts, shackles, steel cables, slings, etc., and their rated load must be greater than the weight of the lifted object (see product catalog for weight data).

Installation specifications and key processes

1. Preparation before installation

Confirm that the nameplate data is consistent with the order, including the mounting position. Changing the mounting position without authorization will invalidate ATEX certification.

The installation base must have sufficient rigidity and flatness (flatness error ≤ 0.2mm/100mm during foot base installation).

All mating surfaces should be cleaned and coated with anti micro corrosion protective paste (such as Kl ü berpaste 46 MR 401 or equivalent).

2. Flange installation

Flange installation is the most common configuration. There are clear regulations on the strength grade and tightening torque of installation bolts (see Table 2 in the manual), for example, M10 × 8 bolts are used for the 300 machine base, and the tightening torque is 85 Nm (12.9 level). Torque wrenches must be used to tighten in the prescribed cross sequence, and cannot be estimated based on experience.

3. Shaft mounted installation (shrink disk)

For the hollow shaft installation method using a shrink disc, the installation quality directly affects the torque transmission capacity and disassembly convenience:

Cleaning and lubrication: Clean and degrease the holes inside the gearbox and the outer surface of the customer shaft. The outer surface of the shrink disc can be lightly lubricated, but the use of molybdenum disulfide or other lubricating grease is strictly prohibited to avoid reducing the friction coefficient and affecting the torque transmission performance.

Installation steps (size 300-313): First, pre tighten 3 bolts in triangular order (position 1-5-9), insert the gearbox into the shaft, and then tighten them in a circular manner until all bolts reach the specified torque.

Installation steps (size 314-325): First, tighten 4 bolts in a cross pattern with 50% torque, then tighten the other 4 bolts in a cross pattern with 100% torque, and finally tighten all bolts continuously until there is no looseness.

Disassembly Tip: If disassembly is difficult, you can use the oil pressure injection hole (1/8 "or 1/4" BSP) on the gearbox to inject pressurized oil to assist in disassembly.

4. Replacement of transport plugs and installation of breathable plugs

The gearbox is equipped with a closed transport plug when it leaves the factory. Before formal operation, it must be replaced with the breathable plug that comes with the box, otherwise the internal pressure will increase during operation, which will cause damage to the oil seal and oil leakage.

Special requirements for ATEX explosion-proof environment

For gearboxes designated for use in potentially explosive environments, the following requirements must be strictly followed:

Only synthetic lubricants (PAG or PAO) are allowed, mineral oils are not suitable.

Surface temperature monitoring: The nameplate of ATEX certified models indicates the highest surface temperature (135 ° C for T4 level and 135 ° C for 2D level). During operation, the surface temperature of the casing must be regularly measured (especially at the connection between the motor and gearbox and the least ventilated area), and must not exceed the allowable value.

Dust environment cleaning: Gearboxes installed in zones 21/22 must develop and implement regular cleaning plans to prevent dust accumulation exceeding 5mm.

Oil level check: ATEX gearboxes installed vertically are usually equipped with expansion chambers and dedicated oil level check rods. During inspection, the inspection rod should be placed at the edge of the threaded hole to ensure that the oil level is not lower than 3mm below the overflow port.

Motor installation: Only motors with ATEX rating equal to or higher than the gearbox can be installed, and the compliance of the entire machine after installation is the responsibility of the final assembler.

Lubrication management

1. Lubricating oil selection

Choose the appropriate type and viscosity of lubricating oil based on work schedule and environmental temperature:

Industrial applications: Mineral oil (EP additive), PAO synthetic oil, or PAG synthetic oil can be selected. Specific recommended brands can be found in the manual charts (Shell, Mobil, Total, etc.).

Mobile machinery: Select according to SAE grade (80W/90, 85W/140) and API GL5 grade.

2. Oil filling

The gearbox does not contain lubricating oil when it leaves the factory (unless specifically specified at the time of ordering). Users need to add the corresponding amount of oil according to the installation position on the nameplate and the table in Annex 2 of the manual. The oil level is based on the mark on the oil level plug, and the data in the table is for reference only.

3. Oil change cycle

The oil change interval depends on the type of oil and operating temperature:

Average oil temperature mineral oil PAO synthetic oil PAG synthetic oil

< 65°C 8,000 h 25,000 h 25,000 h

65-80°C 4,000 h 15,000 h 15,000 h

80-95 ° C 2000 h (within 1 year) 12500 h 12500 h

Attention: It is not recommended to operate continuously within the oil temperature range of 80-95 ° C. Oil temperature exceeding 95 ° C is considered a fault state.

Long Term Stock

For gearboxes with an expected storage period exceeding 6 months (up to 2 years), Bonfiglioli offers specialized long-term storage options:

Packaging method: The gearbox is sealed in a VpCI (vapor phase anti rust) bag, and the outside is a BBOX cardboard box or wooden box. The four walls of the box are marked with "OPEN ONLY BEFORE THE INSTALLATION".

Rust proof fluid: Add anti-corrosion protective fluid inside the gearbox instead of standard lubricating oil.

Compatibility:

SLM option: Rust inhibitor is compatible with all mineral oils and PAO synthetic oils.

SLP option: Rust inhibitor is compatible with all PAG synthetic oils.

Pre operation processing:

If the working oil is compatible with the rust inhibitor: simply add the working oil to the specified level and replace the vent plug.

If not compatible: first drain the rust inhibitor, add 20% oil for "cleaning operation", and then add new working oil after draining.

Extended storage period: After 2 years of storage, it needs to be inspected by Bonfiglioli service center before it can be stored for another 24 months.

Installation of hydraulic motor and hydraulic brake

1. Installation of hydraulic motor

There are two sealing methods between the motor installation flange and the gearbox: O-ring sealing or motor built-in sealing.

Clean the positioning stopper and mating surface before installation, apply lubricating grease, install the motor, and tighten the flange bolts (not lower than grade 8.8).

Drain Port: If a leaking oil pipe is connected, the pressure at the shaft seal is equal to the pressure of the leaking pipeline; If closed, the shaft seal pressure is the average of the inlet and outlet pressures. When multiple motors are connected in series, a leaking oil pipe must be connected.

2. Hydraulic brake

The minimum release pressure of the brake is shown in Table 8 of the manual (e.g. about 10 bar for type 4 brake and about 20 bar for type 6 brake), and the maximum pressure does not exceed 320 bar.

The static braking torque (Mbs) is at its maximum value and may decrease slightly under dynamic conditions. The actual value fluctuates between -5% and+15% of the rated value.

Common faults and troubleshooting

Possible causes and solutions for the fault phenomenon

Bearing temperature too high, oil level too low, oil aging, bearing damage, oil replenishment, oil change, contact authorized maintenance

Operating temperature too high, oil level too high, oil aging, impurities in oil. Check oil level, change oil, change oil

Abnormal operation noise, gear damage, excessive axial clearance of bearings, bearing wear, overload, impurities in oil. Contact authorized maintenance, correct load to rated value, oil change

Abnormal noise at the installation site. Loose or worn installation bolts. Tighten and replace bolts according to torque

Oil leakage, high oil level, seal failure, gasket aging. Check the oil level and contact authorized maintenance

The gearbox does not rotate or has difficulty operating. If the oil viscosity is too high, the oil level is too high, the gear is overloaded, or the gear is damaged, replace the recommended oil, check the oil level, redesign the transmission, and contact authorized maintenance

Maintenance plan and safety precautions

1. Regular inspection items

Every 24 hours: Check the oil pressure (if there is a hydraulic circuit), noise, and vibration levels.

Every 720 hours: Check for external seal leaks, oil level, and oil filter contamination indicators.

Every 2000-4000 hours: Check the torque of all fastening bolts, wear of coupling elastic components, and re lubrication of Drywell seals.

Every time the oil is changed: check the alignment status between the gearbox and the coupling equipment.

2. Safety Warning

Before all maintenance work, the power must be cut off and ensure that it is not accidentally powered on, while taking measures to prevent the suspended load from accidentally moving.

When maintaining in potentially explosive environments, it is also necessary to eliminate residual gases or dust in the environment.

Original spare parts must be used during maintenance. Non original parts not only void the warranty, but may also endanger equipment safety.

The disassembled threaded connection must be reapplied with Loctite 510 or equivalent product.

When replacing the seal, a small amount of fluorocarbon grease (such as Fluorocarbon gel 880 ITP) should be applied to the sealing lip.