An excavator can indicate the characteristics of the machine through a series of parameters, through the parameter comparison users can know the basic performance of an excavator operation.
1. Operating Weight
One of the three main parameters of an excavator is the total weight of the excavator with the standard work unit, driver and a full tank of fuel. The operating weight determines the class of the excavator and the upper limit of the excavator’s digging power.
2. Engine Power
Engine power is one of the three main parameters of an excavator and is divided into gross power and net power, which determines the power performance of excavator.
1. Gross power(SAE 1995) refers to the power output measured at the engine flywheel without power-consuming accessories such as silencers, fans, alternators and air filters.
2. Net power
– means the power output measured at the engine flywheel in the presence of all power consuming accessories such as silencer, fan, alternator and air filter.
– means the power output measured at the engine flywheel when fitted with power consuming accessories necessary for the operation of the engine, generally a fan.
3. Bucket Capacity
One of the three main parameters of an excavator, it is the volume of material that can be loaded in the bucket. An excavator can be equipped with buckets with different bucket capacities depending on the density of the material. Proper selection of bucket capacity is one of the most important means of providing operational efficiency and reducing energy consumption. Bucket capacity is generally divided into two kinds of stacking and leveling bucket capacity, and the commonly used calibrated bucket capacity for excavators is stacking bucket capacity. Stacked bucket capacity according to the different natural angle of repose 1:1 stacked bucket capacity 1:2 stacked bucket capacity two.
5. Operating Range
The inner area of the line connecting the extreme position points that the bucket tooth tips can reach without the excavator rotating. Excavators often utilize graphical representations of the operating range. The operating range of the excavator is usually expressed in terms of maximum digging radius, maximum digging depth, maximum digging height, etc.
6. Transportation Dimensions
Refers to the excavator in the transportation state of the external dimensions. Transportation state generally means that the excavator is parked on a flat surface, the longitudinal centers of the upper and lower bodies are parallel to each other, the bucket cylinders, the bucket cylinder extends the longest length, the moving arm is lowered until the working device touches the ground, and all open parts are in the closed state.
7. Slewing Speed and Slewing Torque
1. Slewing speed: The maximum average speed that excavator can reach when it is unloaded and slewing steadily. The indicated slewing speed does not refer to the slewing speed at either start-up or braking. For general digging condition, when the excavator works in the range of 0°~180°, the slewing motor has acceleration and deceleration, and the slewing speed reaches stability when it turns to 270°~360°.
2. Slewing torque: The maximum torque that can be generated by the excavator slewing system, the size of the the slewing torque determines the ability of slewing acceleration and slewing braking, and it is an important index to measure the slewing performance of the excavator.
8. Traveling Speed and Traction Force
For crawler excavators, walking time accounts for about 10% of the entire working time, the general excavator has a high-speed and low-speed two walking gears, dual-speed can be very good to meet the excavator climbing and level ground walking performance.
1. Traction Force: Refers to the horizontal direction of the excavator walking on the horizontal ground when the pulling force, the main factors affecting the walking motor low-speed gear displacement, working pressure, drive wheel pitch diameter, machine weight and so on. Excavators generally have a large traction force, it is generally 0.7~0.85 times the weight of the machine.
2. Walking Speed: Refers to the maximum walking speed of the excavator when walking on the standard ground. Crawler hydraulic excavator walking speed is generally not greater than 6km/h. Crawler hydraulic excavator is not suitable for long distance walking.
The travel speed and traction force indicate the maneuverability and flexibility of the excavator and its ability to travel.
9. Hill Climbing Ability
The ability to climb, descend, or stop on a firm, level slope. There are two ways to express it: angle and percentage:
1. The angle of climb θ is generally 35°
2. The percentage tanθ = b/a, generally 70%. Miniature machine indicators are generally 30° or 58%.
10. Ground Specific Pressure
Ground specific pressure is the pressure exerted by the weight of the machine on the ground. The size of the ground pressure determines the ground conditions in which the excavator is suitable for work. Ground specific pressure = working weight / total area in contact with the ground.
11. Lifting Capacity
Lifting capacity is the lesser of rated stabilized lifting capacity or rated hydraulic lifting capacity.
1. 75% of rated stabilized lifting capacity for tipping loads
2. 87% of rated hydraulic lifting capacity hydraulic lifting capacity.
12. Productivity
Productivity is one of the main technical and economic indicators of an excavator. However, since productivity is affected by various conditions, it is generally not listed in the table of excavator performance parameters.
1. Theoretical productivity: The productivity of one hour of continuous work under “calculation conditions”. “Calculated conditions” include: skillful operation, common working conditions and working dimensions, and proper location of working and transportation tools.
2. Technical productivity: The productivity of one hour of continuous work under “given conditions”.
3. Actual productivity: The actual average productivity obtained over a period of time when the machine if working. It is based on technical productivity and is influenced by both machine utilization and operating proficiency.
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Post time: Nov-05-2024