How does the tractor clutch system work?

The clutch generally exists in the gearbox of the tractor and plays the role of power separation. In a fuel vehicle, the heart of the power is the engine. When the power output from the engine is to be transmitted to the wheels, it must pass through the gearbox and the drive shaft in the middle. We can call this transmission chain the power transmission system. Then the clutch is located at the head end of the gearbox, and when it is engaged, it allows the transmission system to transmit power smoothly; when the clutch disengages, it cuts off the power transmission from the engine to the wheel end.

So why do you need to cut off the power from the engine to the wheel end? This is mainly related to the working characteristics of the engine. Like a normal engine, there will be a minimum speed requirement, that is, the lowest crankshaft rotation speed for the engine to work smoothly. For example, the minimum speed of the four-cylinder engine is about 500 rpm or more, and the three-cylinder engine is about seven or eight hundred rpm. Below this value, the engine is likely to stall. Therefore, when our car is stationary, the engine should also be kept above this minimum speed. At this time, it is necessary to have a power separation device to realize the connection and separation of power.

On the whole vehicle, the tractor clutch system can be roughly divided into two parts: the control system and the clutch. The control system is the clutch pedal that we operate with our feet, plus a set of transmission devices to transmit the action of the clutch pedal to the clutch. The clutch is a device used to realize the transmission and interruption of engine power.

K series

Let’s talk about several forms of the clutch system. Among them, the control system generally has three forms, rod-type control system, zipper-type control system and hydraulic control system.

Like the rod system, which can be seen on previous tractors and old heavy trucks, the transmission device in their middle is composed of connecting rods. The transmission efficiency of this system is relatively low, the arrangement of the connecting rod is also relatively difficult, the space required is relatively large, and the stroke of the entire pedal will be relatively large. Therefore, the application of the stick control system is relatively limited.

The second type is the zipper control system. It transmits the operation of the pedal to the clutch through a zipper in the middle. This is a similar principle to the handbrake braking mentioned in the previous explanation of the braking system. Although the zipper system is more flexible in terms of spatial arrangement, its transmission efficiency is not high, and its service life is relatively short.

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Details can be accessed by clicking here:https://www.syclutch.com/personal/principle-of-tractor-clutch-system.html

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What should I pay attention to when replacing the slewing bearing?

There are various slewing bearing failures in production activities, such as crane slewing bearing maintenance, excavator bearing slewing bearing and crane slewing bearing maintenance, but in order to ensure that the construction period is completed on time, the slewing bearing has to be replaced, and it will return to normal in a short time. Work. So what are the precautions in the process of replacing the slewing bearing, let’s take a look at it in detail.

Precautions for slewing bearing replacement

1. When it is difficult to disassemble the slewing bearing on rotary table equipment such as excavator slewing bearing, crane slewing bearing and crane slewing bearing, it is generally due to the excessive deformation of the base or the base, which leads to distortion, and the bolts are difficult to rotate normally;

Slewing Bearing

2. The sealing loss of the slewing bearing means that the channel of the slewing bearing is blocked;

3. The lubricating oil channel cannot be refueled, and the slewing bearing is stuck;

4. The cracking sound of the slewing bearing means that the isolation block, steel ball, roller or channel loss is large;

5. When the slewing bearing parts are disassembled, if the taper pin is not easy to be taken out, generally speaking, the head is reversed; when the taper pin is difficult to pull out through the threaded hole, the next steps are:

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Details can be accessed by clicking here:https://www.prsbearings.com/a/news/precautions-for-slewing-bearing-replacement.html

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How to maintain the slewing bearing of the truck crane?

The crane slewing bearing is an important “joint” of the crane, so its maintenance is very important. So how to maintain the crane slewing bearing?

When carrying out maintenance work, pay attention to the danger of being dragged into the rotary pinion, crushing and shearing. When performing the following tasks, the relevant personnel shall ensure that when starting the engine to perform the necessary slewing and luffing operations, any maintenance personnel are not in the danger zone between the main boom, the loading vehicle and the roller, or between the vehicle and the roller. Danger zone between crane operators (in the driver’s cab).

Check the bolts of the slewing bearing

1. Visually inspect the bolts on the slewing bearing before each crane operation or at least once a week;

2. After the slewing bearing has worked for 100 working hours, check whether the bolts are loose, and check again after 300 working hours; after that, check every 500 working hours; in severe working conditions, shorten the inspection interval. If the bolts are found to be loose during the inspection, please stop the construction operation, and immediately contact the local after-sales service department, and the factory or industrial technicians will check and decide whether to disassemble and inspect immediately;

crane slewing bearing

3. The slewing bearing should be filled with lithium-based grease before installation;

4. When replacing the bolts, wipe the bolts clean, apply thread tightening glue, and then tighten them; use the crane according to the requirements of the operation manual and the lifting performance table, or check the tightening bolts regularly as required, so as to avoid the fatigue damage of the bolts.

Routine inspection of slewing bearings

1. Regularly check the flexibility of the rotation; if noise or impact is found, it should be stopped immediately for inspection, troubleshooting, and dismantling and inspection if necessary;

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Details can be accessed by clicking here:https://www.excavatorbearing.com/a/bearing-knowledge/truck-crane-slewing-bearing-maintenance.html

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WHAT ARE THE FORGING PROCESSES OF SPECIAL ALLOY FORGINGS?

Special alloy forging is much more difficult than ordinary carbon steel and low-alloy structural steel. To produce special alloy forgings with geometric dimensions and metallurgical quality that meet the requirements, corresponding technical measures must be taken according to different characteristics. These measures are mainly Including process measures, forging and die design measures, quality control measures, testing of forging performance (based on selection of thermodynamic parameters), simulation of forging process, first piece trial forging, etc. Among the above measures, the process measures that need to be taken are described as follows:

1. Reasonably select the temperature, heating speed and holding time of the blank into the furnace

For special alloys with low thermal conductivity (especially large-sized billets), they should be heated at a low speed with the furnace or preheated in the furnace at 800 ° C ~ 850 ° C and held for a period of time, rather than directly heated in the furnace at the initial forging temperature, and then heated It is heated to the initial forging temperature or transferred to a high temperature furnace at the initial forging temperature; the holding time at the initial forging temperature depends on the alloy, which is generally several times longer than that of alloy structural steel.

Other blanks of aluminum, magnesium, copper and their alloys with higher thermal conductivity than steel can be directly put into the high-temperature furnace, the heating speed can be accelerated and the holding time can be appropriately shortened.

Harvester pusher

2. Properly select the degree of deformation

In view of the characteristics of high alloying degree of special alloys, serious macrosegregation of ingots and forgings, low plasticity and wide critical deformation range, in the forging process, it is necessary to strictly control the degree of deformation of each fire and even the degree of deformation of each stroke of the equipment (deformation degree If it is too large, it may be forged and cracked, and if the degree of deformation is too small, it may fall into the deformation zone, resulting in local grain growth and uneven structure).

3. Strictly control the final forging temperature

In view of the characteristics of high recrystallization temperature and obvious cold work hardening tendency of special alloys, it is necessary to increase or greatly increase the final forging temperature. The forging temperature is about 300°C higher.

4. Reasonably choose the working speed of the forging equipment

For some special alloys that are sensitive to strain rate and slow recrystallization speed, hydraulic presses, mechanical presses and screw presses with lower loading speed should be selected for forging; for high-speed steels with serious mesh fractures, in order to completely crush them For two-shaped broken objects, a forging hammer with high working speed and strong impact force should be selected for forging.

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Details can be accessed by clicking here:https://www.gold-emperor.com/forging-process-flow-of-special-alloy-forgings/

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What are the factors that affect the fuel consumption of concrete mixer trucks?

In the operating cost of concrete enterprises, the proportion of fuel consumption of concrete mixer trucks is as high as 53%. How to reduce fuel consumption has become an urgent problem for enterprise managers to improve. In this regard, the tank car sales manufacturers have made a detailed introduction to the important factors affecting fuel consumption, hoping to help you better.

Factors affecting the fuel consumption of concrete mixer trucks:

concrete mixer truck

The fuel economy factor of the mixer truck 1: The use of the mixer truck

The main factors affecting the fuel economy in terms of use are to keep the technical condition of the concrete mixer truck in good condition and the correct driving operation. Mainly as follows:

a. Correct technical maintenance and adjustment

The adjustment and maintenance of the mixer truck will affect the performance of the engine and the driving resistance of the mixer truck, and have a considerable impact on the fuel consumption per 100 kilometers. Therefore, the correct technical maintenance and adjustment will have a great impact on the fuel economy of the mixer truck.

First of all, keep the engine in good technical condition. Maintain and inspect the oil supply system, air intake system and lubrication system to prevent oil leakage, and timely check the precipitation and impurities in the filter. When the air filter is not smooth, the fuel consumption will increase by about 3%. “Three filters” for maintenance to maintain the correct temperature of the engine cooling system.

In terms of chassis, it is necessary to strengthen the maintenance and adjustment of each assembly to maintain proper sliding ability and reduce fuel consumption. The sliding ability of the cement tanker is often evaluated by the sliding distance, and the sliding distance can be used to check the technical condition of the chassis.

The positioning of the front wheel of the mixer truck, the adjustment of the gap of the brake, the tire pressure, the tightness of each bearing, the clearance of the moving friction part and the lubrication quality will have a great impact on the movement resistance of the mixer truck, and must be adjusted and maintained according to regulations.

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Details can be accessed by clicking here:https://www.ly-cimc-linyu.com/a/news/factors-affecting-the-fuel-consumption-of-concrete-mixer-trucks.html

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How to prevent spontaneous combustion of oil tank truck in summer?

Oil tank truck is a special transportation tool for loading oil products. Because one of the characteristics of oil products is that it can ignite and catch fire at high temperature, oil tank trucks are generally made of good materials to ensure that the oil products inside can be avoided. adversely affected by external factors. So how should a oil tank truck prevent spontaneous combustion in the summer when the temperature is very high?

How to prevent spontaneous combustion of oil tanker in summer

oil tank truck

1. Do not modify without authorization

Every part and structure of the tanker has been specially designed, and it has also undergone various tests to ensure safety. However, if the tanker is modified without authorization during use, it may be For example, the modified circuit and equipment used do not match the power and capacitance, which will lead to fire and spontaneous combustion.

2. Do a careful inspection

Because the temperature in summer is too high, especially when exposed to the sun at noon, the ground temperature can even be as high as more than 50 degrees Celsius. In this case, if the oil tanker is loaded with oil products, the driver must do it before leaving the car. It is necessary to conduct a comprehensive inspection to ensure that there are no abnormalities in the electrical appliances and wiring of the tanker, as well as the fuel supply system. In addition, a fire extinguisher that has undergone safety monitoring is also required.

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Details can be accessed by clicking here:https://www.ly-cimc-linyu.com/a/news/summer-oil-tank-truck-spontaneous-combustion.html

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How to choose the right storage shelf?

The role of storage shelves in the logistics warehouse is very important, which not only affects the production efficiency of the enterprise, but also affects the management efficiency of the warehouse. The premise of how to effectively use storage shelves is to choose a racking system that suits you, so how do we choose a suitable storage rack?

First, we need to understand the principles of warehouse shelf design

Mobile carts

1. Design principles of warehouse shelves

1. Increase the storage space and maximize the use of space. Every enterprise warehouse has its fixed cost. How to maximize its economic benefits in this space is an important principle of warehouse shelf design.

2. Cargo-oriented, in line with the principle of storing goods

In the final analysis, warehouse shelves are shelves for storing goods. Naturally, warehouse shelves suitable for storing goods should be designed. Therefore, it is necessary to have a comprehensive understanding of the cargo itself, including data such as shape, size, and weight. The data can be provided by the warehouse or measured on-site by the shelf supplier.

3. Fully understand the warehouse environment and related equipment principles

(1) Warehouse structure: including warehouse area, warehouse type, warehouse channels, warehouse effective total height, warehouse column position, warehouse floor, warehouse fire-fighting facilities, etc.;

(2) Related equipment: forklifts, stackers, elevators, etc. It should be noted that the forklift needs to know the required aisle, turn length, etc.

4. The principle of effective circulation of goods and effective management

(1) The management method of goods: carefully listen to the purchasing enterprise’s management method of goods, and formulate a plan for the reasonable arrangement of warehouse shelves;

(2) Mode of goods circulation: including manual or mechanical handling of goods, aisle position, first-in, first-out, whole-in, whole-out, etc.

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Details can be accessed by clicking here:https://www.etegreen.com/blog/storage-shelf-choose/

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CHARACTERISTICS OF ALUMINUM ALLOY FORGING PROCESS

Aluminum alloy has begun to be used more and more in the electric vehicle industry. At the same time, aluminum alloy material is also the most widely used metal in all walks of life. The output of aluminum alloy is second only to steel. Aluminum alloys generally have processes such as casting, forging and die casting in the industry.

Different processes meet different application requirements. Among them, aluminum alloy forging has a series of excellent characteristics. After forging, the metal structure of the aluminum alloy can be changed, and the performance of the aluminum alloy can be effectively improved.

CHARACTERISTICS OF ALUMINUM ALLOY FORGING

First of all, the internal organization is fine, uniform and defect-free, and its reliability is far away. It can be processed into high-precision forging with complex shapes, and the machining allowance is small, only about 20% of the machining allowance of the aluminum alloy drawing thick plate, which greatly saves man-hours and costs. Second, the thermal conductivity is good.

The forging temperature range is narrow, and the requirements for the forging temperature are always strict. The performance characteristics of heating die forging are that the aluminum alloy does not produce allotropic transformation. It mainly depends on the correct control of the forging mechanical parameters to improve the metal structure, so that the metal streamline is uniformly and continuously distributed along the forging shape. to improve mechanical properties.

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Details can be accessed by clicking here:https://www.gold-emperor.com/aluminum-alloy-forging-process/

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Maintenance of hydraulic excavator slewing bearing

Hydraulic excavators generally use single-row four-point contact ball-type internal gear slewing bearings. During the excavator operation, the excavator slewing bearing bears complex loads such as axial force, radial force and tipping moment, and its reasonable maintenance is very important. The maintenance of the excavator slewing bearing mainly includes the lubrication and cleaning of the raceway and the inner gear ring, the maintenance of the inner and outer oil seals, and the maintenance of the fastening bolts. Now from these seven aspects will be described in detail.

1. Lubrication of raceways

Slewing bearing rolling elements and raceways are easy to damage and fail, and their failure rate is high. During the use of the excavator, adding grease to the raceway can reduce the friction and wear among the rolling elements, the raceway and the spacer. The space of the raceway cavity is small, and the resistance to filling grease is large, so manual filling with a manual grease gun is required. The lubricating oil nozzles of the slewing bearing raceway are generally distributed at the position of the outer wall of the slewing bearing.

The raceway cavity is generally lubricated with 2# file-based grease, and the grease filling cycle is generally 100h. Under special working conditions such as high dust, high temperature, and continuous operation, the filling cycle should be appropriately shortened. When adding grease, it is necessary to rotate the slewing bearing, and add it about once every 15°~25°. When filling, pay attention to observe the outer sealing ring of the slewing bearing. When you see grease seeping out from the outer sealing ring, stop filling.

When the raceway cavity is filled with grease, bad filling methods such as “refueling in static state” and “single-point oiling” should be avoided, because the above-mentioned bad filling methods will cause local oil leakage of the slewing bearing, and even cause the oil seal of the slewing bearing to become permanent. Damaged, resulting in grease loss, impurity intrusion, and accelerated raceway wear. Be careful not to mix different types of grease to avoid premature failure.

When replacing the seriously deteriorated grease in the raceway of the slewing bearing, the slewing bearing should be rotated slowly and uniformly while filling, so that the grease can be filled evenly in the raceway. This process can not be rushed, it needs to be done step by step to complete the metabolism of grease.

excavator slewing bearing

2. Maintenance of the gear meshing area

Open the metal cover on the base of the slewing platform to observe the lubrication and wear of the ring gear of the slewing bearing and the pinion of the slewing motor reducer. A rubber pad should be placed under the metal cover and fastened with bolts. If the bolts are loose or the rubber gasket fails, water will seep from the metal cover into the lubricating cavity (oil collecting pan) of the rotating inner gear ring, causing premature failure of the grease, reduced lubrication effect, and increased gear wear and corrosion.

The method of replacing the grease in the lubricating cavity of the ring gear is as follows: first, use the working device to support the excavator, and the operator goes under the crawler frame of the excavator and opens the metal cover; secondly, drop the excavator to the ground and start the excavator Do the rotating action for about 10 laps, and the failed grease can be exhausted. The lubricating cavity of the ring gear of the slewing bearing is also filled with 2# file base grease. The replacement cycle is generally 2000h, and the filling amount should be determined according to the model of the excavator.

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Details can be accessed by clicking here:https://www.excavatorbearing.com/a/bearing-knowledge/maintenance-of-excavator-slewing-bearing.html

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Analysis of Preloading Method of High Precision Crossed Roller Bearings

The preload of the crossed roller bearing means that after the bearing is installed on the bearing seat and the shaft, certain measures are taken to produce a quantitative pre-deformation between the rolling elements in the bearing and the inner and outer rings, so as to keep the inner and outer rings in the same position. pressed state. The purpose of preloading the crossed roller bearing is to: increase the rigidity of the support; reduce vibration and noise; prevent the sliding of the rolling elements relative to the inner and outer raceways caused by the moment of inertia. Depending on the application, the bearing arrangement must have a positive or negative operating clearance. In most cases, the working clearance is positive, that is, when the bearing is running, there is a certain residual clearance, although it may be a small clearance.

On the other hand, there are many applications that require negative operating clearance—that is, negative preload—to increase the rigidity or rotational accuracy of the bearing arrangement. For example, spindle bearings of machine tools, CNC machine tool turntable bearings, thin-walled cross-roller bearings of robot arms, pinion bearings in automobile transmission shafts, small motor bearings, or bearing arrangements for reciprocating motion, etc. In some applications, if the imported bearing is under no or only small load, and operates at high speed, preload should be carried out on the bearing arrangement, such as by spring to carry out bearing preload. In this case, the role of preload is to provide a small load to the bearing to prevent the rolling elements from sliding and causing damage to the imported bearing.

crossed roller bearing

So what are the preload forms of the bearing?

The preload form can be radial or axial according to different bearing types. For example, cylindrical roller bearings, due to their design, can only be preloaded in the radial direction, while thrust ball bearings and thrust cylindrical roller bearings can only be preloaded in the axial direction. Single row angular contact ball bearings and tapered roller bearings are generally axially preloaded and are usually paired with another imported bearing of the same type back-to-back or face-to-face. And deep groove ball bearings are usually also subjected to axial preloading. In order to achieve the purpose of preloading, a radial internal clearance larger than that of the ordinary group should be used, so that it can have a larger than zero clearance like an angular contact ball bearing. Contact angle.

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Details can be accessed by clicking here:https://www.prsbearings.com/a/news/crossed-roller-bearing-preload-method.html

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