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1. Why are forklift brakes the core of the braking system?
In the modern logistics industry and warehousing operations, forklifts are indispensable handling tools, and their safety performance has attracted more and more attention. The braking system is a key component to ensure the safe operation of forklifts, and its performance is related to the working efficiency of the forklift and the prevention of emergencies. Forklift brakes are specially designed to control the deceleration, parking and stationary state of forklifts. They convert kinetic energy into heat energy to achieve vehicle deceleration and stopping. With the advancement of industrial technology, forklift brakes have developed from simple mechanical devices to complex braking systems that integrate mechanical, electronic and hydraulic technologies.
l The role of forklift brakes
As an important part of the vehicle safety system, forklift brakes have many important functions. The basic functions are mainly reflected in three aspects: the deceleration function enables the forklift in motion to reduce speed as needed; the parking function ensures that the forklift can stop completely at the predetermined position; the parking function ensures that the forklift remains stationary when stopped to prevent accidents during movement. The realization of these basic functions is an important prerequisite for ensuring the safety of forklift operations.
In terms of safety performance, forklift brakes play a vital role. A high-performance braking system can reduce the accident rate and protect the safety of operators, surrounding staff and goods. Especially in special environments such as slippery ground and slope operations, a reliable braking system can prevent the forklift from slipping and losing control. According to data, about 15% of forklift-related accidents are related to brake system failures or insufficient performance, which highlights the importance of high-quality brakes.
From the perspective of operation control, today's forklift brakes not only provide basic safety guarantees for operators, but also greatly improve the accuracy and comfort of operation. The progressive braking feel allows the operator to accurately control the parking position, which is particularly critical for precision handling operations in narrow spaces. In addition, good braking performance can also reduce damage to goods caused by sudden braking and reduce the company's cargo damage costs.
l Working principle of forklift brakes
Forklift brakes are mainly divided into three types according to their technical principles: mechanical, hydraulic and electronic. Mechanical brakes are the most traditional form of braking, which transmits pedal force to the brake drum or brake pads through a lever and cable mechanism. When the operator steps on the brake pedal, the mechanical linkage system amplifies the force and acts on the brake shoe, causing it to contact the rotating brake drum to generate friction. This brake system has a simple structure and low cost, but the braking force transmission efficiency is relatively low, and regular adjustments are required to compensate for shoe wear.
The hydraulic brake system is the most widely used in forklifts. It uses the Pascal principle to achieve force amplification and transmission. The system mainly consists of a brake master cylinder, a wheel cylinder, a hydraulic pipeline and a brake pad. When the pedal is stepped on, the brake fluid in the master cylinder generates pressure, which is evenly transmitted to the brake wheel cylinder of each wheel through the hydraulic pipeline, pushing the brake pad to clamp the brake disc. The advantages of the hydraulic system are uniform braking force distribution, rapid response, and automatic wear compensation. A typical hydraulic brake system can establish maximum braking force within 300-500 milliseconds, and the braking distance is about 20% shorter than that of a mechanical system.
The electronic brake system is the latest development in forklift braking technology. It integrates an electronic control unit (ECU), sensors and electro-hydraulic actuators. The system monitors the pedal travel, vehicle speed and load in real time through sensors, and the electronic control unit can calculate the braking force and control the actuator action. This intelligent braking system can realize a variety of advanced functions, such as anti-lock braking (ABS), traction control (TCS) and electronic brake force distribution (EBD). Data shows that forklifts equipped with electronic braking systems can reduce the braking distance on slippery roads by 30%, improving operational safety. In addition, the electronic system can also realize functions such as braking energy recovery and utilization to improve the energy utilization rate of the entire vehicle.
l Application scenarios of forklift brakes
Forklift brakes face various challenges and requirements in different working environments. In indoor storage environments, the ground is usually relatively flat but the space is limited. The braking system needs to provide precise deceleration control to ensure that the forklift can operate accurately in narrow passages. In this scenario, the sensitivity and progressiveness of the brake are particularly important, and the noise and dust generated during braking are required to be as little as possible to maintain a good working environment.
Working in outdoor environments requires higher requirements for the braking system. Uneven roads, slopes and various weather conditions will affect the braking performance of forklift brakes. When running on a slope with a gradient of more than 5%, the braking system must not only provide sufficient braking force to prevent slipping, but also have good heat dissipation performance to avoid performance degradation caused by long-term braking. In the face of dusty, humid or oily working environments, specially designed sealed brakes can effectively prevent pollutants from invading and maintain stable braking performance. Data shows that working in special outdoor environments, high-performance braking systems can reduce the accident rate by more than 40%. In the face of slippery roads, forklift brakes have adopted a number of innovative designs. The anti-skid control system monitors the speed of each wheel in real time through the wheel speed sensor. When it detects that the speed of a certain wheel is abnormally reduced (indicating that it is about to slip), it immediately adjusts the braking force of the wheel. This active safety intervention can shorten the braking distance on slippery roads by more than 30%. At the same time, the specially formulated friction material can still maintain a stable friction coefficient in a humid environment, avoiding the problem of a sudden drop in braking force of traditional materials after contact with water.
Special application scenarios such as cold storage and explosion-proof environments have special requirements for brakes. Forklift brakes for cold storage must be able to work stably at temperatures of -30°C or even lower, using special low-temperature rubber seals and antifreeze hydraulic oil. Brakes used in explosion-proof environments need to eliminate any risk of sparks, and usually use a fully enclosed design and special friction materials. In heavy-duty applications such as ports and container yards, the braking system needs to have good thermal capacity and durability to cope with frequent heavy-duty braking needs.
l Features of forklift brakes
Modern forklift brakes use a number of advanced technologies in terms of safety. The dual-circuit hydraulic system is the standard configuration of current mid-to-high-end forklifts. When one circuit fails, the other circuit can still maintain at least 50% of the braking force, which improves system reliability. The anti-lock braking system monitors the wheel status through the wheel speed sensor and automatically adjusts the braking force during emergency braking to prevent loss of control caused by wheel locking.
Durability and maintenance convenience are important indicators for evaluating brake quality. Good brakes use high-hardness alloy cast iron brake discs and sintered metal friction pads, and their service life can reach more than 3 times that of ordinary materials. The modular design reduces the time for replacing brake pads to less than 30 minutes, greatly reducing maintenance costs. The self-adjusting mechanism can automatically compensate for friction pad wear and keep the brake pedal travel consistent, eliminating the trouble of frequent adjustments.
Intelligence and environmental protection are the main trends in the development of brake technology. The intelligent braking system can work with other forklift systems to optimize the distribution of braking force according to load weight, driving speed and road conditions. The energy recovery system converts the heat energy generated during braking into electrical energy storage, which can improve the energy efficiency of the whole machine by 15%. In terms of environmental protection, copper-free and asbestos-free friction materials have become the industry standard. The use of this material can effectively reduce the emission of harmful dust.
2. Maintenance and care of forklift brakes: key measures to ensure safe operation
As a core component to ensure operational safety, the performance of the forklift brake system is directly related to the safety of operators, equipment and the surrounding environment. According to statistics, nearly 23% of forklift accidents are related to brake system failures or improper operation.
l The importance of forklift brake maintenance
Forklift brakes are important components for the safe operation of industrial vehicles, and the quality of their maintenance is directly related to operational safety and the service life of the equipment. As one of the important safety systems of forklifts, brakes convert the vehicle's kinetic energy into heat energy through friction to achieve the three functions of deceleration, parking and parking. According to statistical data, a properly maintained brake system can reduce forklift-related accidents by more than 40%, while extending the service life of the brake by 2-3 times.
l Three levels of maintenance of forklift brake system
Daily maintenance is carried out by forklift drivers before and after each shift, mainly including cleaning, inspection and simple adjustment; regular maintenance is divided according to the number of operating hours. Internal combustion forklifts generally undergo first-level maintenance after 150 working hours, second-level maintenance after 450 hours, and electric forklifts after 500 hours and 2500 hours respectively; professional maintenance must be performed by certified technicians, involving in-depth disassembly and performance testing of the brake system. This hierarchical maintenance system ensures that the brakes are always in good working condition.
From a technical point of view, brake maintenance mainly focuses on four parts: the wear state of friction parts (brake pads/shoes, brake discs/drums), the sealing of the hydraulic system (brake fluid, oil pipes, slave cylinders), the flexibility of mechanical transmission (pedals, connecting rods, springs) and the accuracy of electronic control (ABS, EBD sensors). The performance of these four aspects determines the overall effect of the brake system.
Table: Main components and maintenance focus of forklift brake system
|
Component categories |
Main components |
Maintenance key points |
|
Friction parts |
Brake pads, brake discs, brake drums |
Wear, cracks, oil stains |
|
Hydraulic system |
Brake master cylinder, wheel cylinder, oil pipe |
Fluid level, leakage, air resistance |
|
Mechanical parts |
Pedals, pull rods, return springs |
Free travel, corrosion, elasticity |
|
Electronic system |
Wheel speed sensor, ABS module |
Signal transmission, line connection |
l Inspection and maintenance points of forklift brake system
Daily inspection of forklift brake system is the core of safety guarantee, and the inspection standards should be strictly implemented by trained forklift drivers before and after work. This preventive maintenance procedure can not only detect potential problems in time, but also extend the service life of brake components. A complete daily inspection should cover three main links: brake performance test, appearance inspection and simple maintenance.
Braking performance test is the core content of daily inspection. After the driver starts the forklift, he drives at a speed of 5-10km/h in a safe area, and lightly presses the brake pedal to test the braking response speed. The hydraulic brake system is required to establish effective braking force within 300-500 milliseconds. Then an emergency brake test is performed to confirm that the braking distance at a speed of 8km/h does not exceed 0.8 meters and the vehicle does not deviate. The parking brake test needs to be carried out on a 15% slope. After tightening the handbrake, the vehicle can remain stable and stationary without slipping. During the test, pay attention to whether there is abnormal friction sound, which is often a signal of brake pad wear or foreign matter entering.
Pedal inspection: The free travel of the brake pedal is the key inspection item, and the standard value is usually 5-10mm. The measurement method is very simple. Press the pedal lightly with your hand until you feel resistance. This distance without resistance is the free travel. Too much travel will cause braking lag, and too little travel may cause drag. At the same time, pay attention to the change in pedal pressure during the inspection. If it feels "softer" than usual or requires deeper pedaling to brake, it may indicate that there is air blockage or leakage in the hydraulic system.
Hydraulic system inspection: The brake fluid level must be between the oil cup mark range. Too low a level will cause brake failure. When checking, pay attention to the color of the oil. Normally it should be clear light yellow. If it turns dark brown or black, it means that it has been oxidized and deteriorated and needs to be replaced immediately. At the same time, carefully check whether there are any signs of leakage at the brake master cylinder, wheel cylinder and various pipeline connections, especially in hidden locations such as the inside of the wheel.
Visual inspection of friction parts: Check the remaining thickness of the brake pad through the brake observation hole or disassemble the wheel. It must be replaced when it is worn to 2mm. Check whether the surface of the brake disc/drum is smooth and whether there are obvious grooves and cracks. If oil is found on the friction surface, it must be cleaned and the cause of the oil leakage must be found out.
Table: Daily inspection items and standards for forklift brake system
|
Inspection items |
Inspection methods |
Qualification standards |
Disposal measures |
|
Brake pedal |
Touch test |
Free travel 5-10mm |
If it exceeds the limit, the connecting rod needs to be adjusted |
|
Braking performance |
Road test |
8km/h braking distance ≤ 0.8m |
If unqualified, repair required |
|
Parking brake |
Slope test |
Stay still on 15% slope |
Adjust wire tension |
|
Brake fluid |
Visual inspection |
Liquid level is within the standard range |
If insufficient, add the same type of |
|
Friction plate |
Thickness measurement |
≥2mm remaining thickness |
Replace immediately if exceeding the limit |
l Cleaning and maintenance are also indispensable
During the cleaning process, use compressed air to remove dust and debris around the brake, especially dust accumulation in the heat dissipation hole area of the brake disc. For metal parts exposed to the external environment, such as pedal fulcrums, handbrake cables, etc., apply an appropriate amount of lithium-based grease to prevent rust, but remember to avoid friction surfaces when lubricating. Check whether each fastener (such as caliper bolts, brake drum fixing screws) is loose, and re-tighten it according to the standard torque. Finally, update the maintenance label to record the inspection date, personnel and problems found, providing a basis for subsequent maintenance.
If any abnormality is found during daily inspections, such as brake pedal sinking, uneven braking force, abnormal noise, etc., the forklift must be stopped immediately and the "fault to be repaired" sign must be hung to notify professional maintenance personnel to handle it. These seemingly simple daily inspection measures can prevent more than 80% of sudden failures in the brake system.
3. Regular maintenance content and technical specifications
Regular maintenance of the forklift brake system is a key measure to maintain its long-term reliability. It can be divided into two levels of maintenance: primary maintenance and secondary maintenance according to the operating time. Internal combustion forklifts usually perform primary maintenance after 150 hours of work and secondary maintenance after 450 hours; electric forklifts perform corresponding levels of maintenance after 500 hours and 2500 hours respectively. This maintenance cycle based on working hours is more scientific than a fixed time interval and can accurately reflect the actual wear condition of the brake.
l Primary maintenance is mainly based on cleaning, lubrication and adjustment --
When maintaining, first clean the entire brake system and use a special brake cleaner to remove oil and friction dust on the brake disc and brake pads. These pollutants will reduce the friction coefficient. For drum brakes, the brake drum needs to be disassembled to clean the brake dust accumulated inside. These fine particles will accelerate the wear of the brake shoe. Check the quality of the brake fluid. If the water content exceeds 3% or the service time exceeds 2 years, it must be replaced completely. It is strictly forbidden to mix different models when replacing. Exhausting the hydraulic system is another key step. According to the principle of "from far to near" (the wheel cylinder farthest from the master cylinder is exhausted first), use special exhaust equipment or two people to step on the pedal to exhaust the air until there are no bubbles in the oil. Brake pedal mechanism: Check the wear of the pedal shaft bushing. Excessive looseness will cause uneven braking force transmission. Lubricate all hinge points, but avoid grease contamination of the friction surface.
Parking brake system: Adjust the wire rope tension to ensure that sufficient braking force can be provided within 70% of the stroke. Check whether the ratchet mechanism is worn to ensure that it can lock reliably.
Wheel cylinder and seals: Check whether the hydraulic wheel cylinder has leakage and whether the dust cover is broken. These rubber parts should be replaced preventively every 2 years to prevent hydraulic oil leakage caused by cylinder aging.
l Secondary maintenance requires disassembly and inspection of the brake system--
Brake disc thickness measurement is the key point. Use an outside micrometer to measure at multiple points. If the thickness difference exceeds 0.01mm or the wear exceeds 10% of the original thickness, it needs to be processed or replaced. Drum brakes need to check the inner diameter roundness of the brake drum. If the roundness exceeds 0.1mm, boring and repair are required. At the same time, check the elasticity of the brake shoe return spring and replace the deformed or weakened spring. The failure of these seemingly small parts will cause brake drag. The deep maintenance of the hydraulic system includes: replacing all brake hoses. These rubber hoses must be replaced every 2 years; disassembling and cleaning the master cylinder and wheel cylinder, and checking whether there are scratches or corrosion on the cylinder wall; testing the working status of the proportional valve to ensure that the front and rear axle braking force distribution meets the standard. For the electronic brake system, use a diagnostic instrument to read the ABS module data, check whether the wheel speed sensor signal is stable, and clean the sensor probe surface.
4. Diagnosis and treatment of common faults in the brake system
Failures in the brake system of forklifts will reduce the safety of operations, and timely and accurate diagnosis and treatment are essential. According to maintenance statistics, brake system failures are mainly concentrated in four categories: insufficient braking efficiency, brake deviation, abnormal noise and drag. Mastering the diagnosis methods and treatment techniques of these common problems can effectively shorten equipment downtime and reduce maintenance costs.
- Insufficient braking efficiency: mainly manifested as too long pedal stroke or need to step hard to slow down. When checking, you should first observe the brake fluid reservoir. Low fluid level usually indicates that there is a leak in the system. You need to carefully check whether there are signs of leakage in each oil pipe joint, wheel cylinder and master cylinder. If the fluid level is normal but the pedal is soft and weak, it may be that air has entered the hydraulic system, and exhaust operation is required: connect a transparent hose to the collection bottle on the wheel cylinder exhaust screw, keep the pedal pressed after continuous stepping, loosen the exhaust screw to discharge the oil with bubbles, and repeat until pure oil flows out. If it is still ineffective after exhausting, it may be that the master cylinder seal has failed, and it needs to be disassembled to check whether the master cylinder leather cup is damaged. Another situation is that the pedal is hard but the braking force is insufficient, which often indicates that the friction pad surface is oiled or the brake pad is excessively worn.
- Braking deviation:refers to the forklift leaning to one side when braking, which is easy to cause a loss of control accident. Pay attention to the tire pressure during the inspection. If the tire pressure difference on both sides exceeds 10%, it will cause uneven distribution of braking force. If the tire pressure is normal, it is necessary to measure the brake clearance on both sides: jack up the wheel, turn and adjust the brake shoe clearance until there is slight friction, and ensure that both sides are consistent. Unilateral leakage of the hydraulic system can also cause deviation. Observe which side of the brake is not sensitive, and focus on checking the wheel cylinder and oil pipe on that side. For models equipped with proportional valves, valve body blockage or malfunction can also cause brake force distribution imbalance, which requires professional maintenance.
- Abnormal brake noise:Hearing a sharp metal friction sound usually indicates that the brake pad wear limit indicator has contacted the brake disc, and the brake pad must be replaced immediately. If there is still abnormal noise after replacing the new pad, it may be that the brake disc surface is uneven (check that the runout exceeds 0.1mm and needs to be turned) or the silencer is improperly installed. The dull knocking sound may come from the loose front wheel bearing or suspension components, and the chassis fasteners need to be fully checked.
- Brake drag:It is manifested as large driving resistance of the forklift and severe brake heating. Common causes include no free travel of the brake pedal, broken return spring or insufficient elasticity, and blockage of the hydraulic system oil return hole. During diagnosis, the wheel can be jacked up. It should be able to rotate easily under normal circumstances. If there is a sense of blockage, adjust the brake clearance first; if it still does not work, disassemble and inspect the caliper or wheel cylinder to check whether the piston is rusted and stuck. For handbrake drag, focus on checking whether the pull wire is rusted and stuck, and whether the adjustment mechanism is too tight.
5. Maintenance precautions
The maintenance of forklift brake systems itself has many safety hazards. Complying with safety precautions can effectively prevent accidental injuries and equipment damage during maintenance. According to statistics, about 18% of forklift maintenance accidents occur during brake system maintenance, mainly due to risks such as improper lifting operations, brake fluid corrosion and accidental release of springs. Scientific safety protection measures are essential to ensure the safety of maintenance personnel.
Personal protective equipment is a safety barrier for maintenance operations. Maintenance personnel must wear a full set of protective equipment: non-slip gloves (to prevent brake fluid corrosion), safety glasses (to prevent high-pressure oil splashing and eye injuries), and steel-toed safety shoes (to prevent heavy objects from hitting them). When disassembling the brake drum, you should also wear a face shield, especially when the brake drum is severely corroded, it may suddenly break and fly out fragments. Use a mask when handling waste brake pads to prevent inhalation of asbestos fibers (some old brake pads contain asbestos). Work clothes should be made of oil-proof materials to avoid contact between the brake fluid and the skin. If contact is made accidentally, rinse immediately with plenty of clean water.
Vehicle fixing and lifting: Before maintenance, the forklift must be parked on a level surface, in neutral gear, with the parking brake engaged, and wheel chocks placed in front and behind the drive wheels. When using a hydraulic jack or lift to lift the vehicle, ensure that the support point is at the designated position of the frame, and do not apply force to weak parts such as oil pipes and connecting rods. Immediately install the safety bracket after lifting, and it is strictly forbidden to disassemble and install the brakes by supporting the vehicle only with the hydraulic system. When removing the front wheel brakes, it is recommended to add additional blocks at the rear wheels to prevent the vehicle from moving forward and backward.
Hydraulic system pressure relief: Before loosening the hydraulic connection, the system pressure must be completely released, the engine turned off, and the brake pedal repeatedly stepped on more than 20 times until the pedal feels hard. When removing the wheel cylinder or caliper, first clamp the flexible brake hose with a special clamp to prevent brake fluid leakage. Use a container to hold the discharged waste fluid, and do not discharge it directly into the sewer (brake fluid is a hazardous waste). The removed hydraulic components should be immediately sealed with a special dust plug to prevent dust from entering the precision valve body. Be aware of the danger of spring energy storage during the disassembly and assembly of the brake. The return spring of the drum brake stores a large amount of energy and must be removed with a special tool (brake spring pliers). It is forbidden to pry with non-special tools such as screwdrivers. Before removal, temporarily fix the spring with a cable tie to prevent accidental popping. When installing new brake pads, ensure that all silencers and shock pads are properly in place. These accessories can reduce more than 80% of brake noise. The caliper guide pins of the disc brake need to be lubricated with special silicone-based grease (conventional butter will corrode the rubber sleeve) to ensure smooth piston return. Brake fluid handling requires special care. Different types of brake fluids are strictly prohibited from mixing. Chemical incompatibility will cause system failure. Use a sealed pressure filler when adding new fluid to prevent air from entering the system. Waste brake fluid should be collected in a special container and handed over to a qualified hazardous waste treatment unit for disposal. It must not be mixed with ordinary waste oil. The maintenance site should be equipped with an emergency treatment kit, including an adsorbent pad (to handle leaks), a neutralizer (to handle brake fluid) and an emergency flushing fluid (for eye flushing).
Table: Hazard sources and control measures for brake system maintenance
|
Hazards |
Potential harm |
Control measures |
|
Hydraulic oil spray |
Eye damage, skin corrosion |
Wear protective glasses and masks |
|
Brake drum rupture |
Flying debris injury |
Use face shield |
|
Spring ejection |
Strike damage |
Special tools, pre-fixation |
|
Asbestos fibers |
Lung diseases |
Use wet disassembly, N95 masks |
|
Brake fluid fire |
Burns |
Keep away from open flames and no smoking |
Post-maintenance testing is the last checkpoint to ensure safety. After completing maintenance, do not install the wheel first, and manually rotate the brake disc/drum to check for abnormal friction. After starting the engine, step on the brake pedal at rest to feel whether its travel and force are normal. Perform a low-speed (within 5km/h) braking test, and gradually increase the test speed after confirming that there is no deviation and abnormal noise. After maintenance of the ABS system, it is necessary to verify whether the ABS starts normally on a slippery test road surface (or simulated low-adhesion road surface) (the pedal should have an obvious pulsating feeling). All tests must be carried out in a safe area, and warning cones must be set up to prevent other people from entering the test area. Maintenance personnel should receive regular safety retraining, especially when new tools and new processes are introduced. The company's safety department checks the compliance of maintenance operations every quarter and reviews the use of personal protective equipment and equipment conditions. By strictly implementing these safety precautions, the risks in the brake system maintenance process can be minimized, ensuring the safety of personnel while ensuring the quality of maintenance.
6. How to choose forklift brakes suitable for different working conditions?
Conventional warehouse environments are common application scenarios for forklifts, which usually have the characteristics of flat ground, limited space, and regular working rhythm. The main requirements for the braking system in this type of working conditions are precise control and durability. In a storage environment, forklifts often need to be precisely positioned in narrow passages, and the brakes must provide progressive and linear braking force to ensure millimeter-level accuracy when stacking goods. According to the JBT 3341-2005 standard, the braking distance of a warehouse forklift should be controlled within 1/10 of the vehicle speed.
Hydraulic disc brakes are ideal for conventional warehouse conditions, with the advantages of fast response and easy maintenance. Disc brakes generate friction by clamping the brake disc with calipers, and have good heat dissipation performance, which is suitable for the frequent start-stop working characteristics of warehouse forklifts. For electric warehouse forklifts, brakes equipped with energy recovery systems can be given priority. This system converts kinetic energy into electrical energy storage during braking, which can reduce the wear of mechanical brake components and extend battery life, achieving the effect of "killing two birds with one stone". It is worth noting that forklift brakes in storage environments should have dust-proof design to prevent packaging material debris and dust from entering the brake system, affecting its sensitivity and service life.
In terms of specific selection parameters, the following technical indicators should be paid attention to forklift brakes:
Pedal force: usually no more than 300N to ensure operating comfort
Durability: brake pad life is generally not less than 2000 working hours
Noise level: should be less than 75 decibels in indoor environments
Braking torque: should meet the braking distance requirements under no load and rated load
For high-position storage forklifts (gantry height exceeds 6 meters), special attention should be paid to stability control during braking to prevent safety hazards caused by cargo swinging. Such applications can consider equipping with an electronic brake force distribution system (EBD) to automatically adjust the front and rear axle braking force ratio according to the load weight to keep the vehicle running stably.
The outdoor working environment places more special requirements on the forklift braking system. Uneven roads, slope operations, windy and rainy weather and other factors will affect the braking performance.
Multi-disc wet brakes are more suitable for outdoor heavy-load conditions, and their heat dissipation performance is more than 50% higher than that of traditional single-disc brakes. This type of brake soaks the friction pair in oil, removes heat through oil circulation, and can work for a long time without thermal decay. At the same time, the oil can also prevent pollutants such as mud, sand, and rain from directly contacting the friction surface, greatly extending the maintenance cycle. For forklifts operating in port container yards, it is recommended to choose a multi-disc brake system with a brake disc diameter of ≥400mm to provide sufficient braking torque to cope with heavy loads.
Ramp operation is another special case of outdoor working conditions, especially continuous braking when going downhill will cause the brake temperature to rise sharply. To address this problem, modern forklifts can use a combined braking system that combines friction braking with a hydraulic retarder or an electromagnetic retarder. When going down a long slope, the retarder can share about 40% of the braking load, effectively avoiding overheating and failure of the friction material. The military standard stipulates that the maximum climbing grade of a 2-ton forklift when fully loaded should be ≥15%, which puts forward clear requirements on the thermal capacity of the braking system.
