operating weight

Operating weight is one of the three important parameters of an excavator (engine power, bucket capacity, operating weight).

The operating weight determines the level of the excavator and determines the upper limit of the excavator's digging force.

Digging force≦m.

working weight

m: Coefficient of adhesion between the ground and the track.

If the digging force exceeds this limit, in the case of a backhoe, the excavator will slip and be pulled forward, which is very dangerous. In a shovel situation, the excavator will skid backwards.

Digging force

For the digging force, the digging force is mainly divided into the arm digging force and the bucket digging force.

The action points of the two digging forces are both the tooth roots of the bucket (the lip of the bucket), but the power is different. The forearm digging force comes from the forearm cylinder; the bucket digging force comes from the bucket oil cylinder.

ground pressure

The size of the ground specific pressure determines the ground conditions for the excavator to work.

Ground pressure refers to the pressure exerted by the weight of the machine on the ground, expressed by the following formula:

Ground specific pressure = working weight ÷ total area in contact with the ground

Track shoe

·It is important to install the proper track shoes on the machine. For crawler excavators, the criteria for selecting tracks is to use the narrowest track shoes whenever possible.

·Common track type: toothed track shoes.

Walking speed

For crawler excavators, the walking time accounts for about one tenth of the entire working time.

Generally speaking, two speeds can meet the walking performance of the excavator.

traction

Traction force refers to the force generated by the excavator when it travels, which mainly depends on the travel motor of the excavator.

These two walking performance parameters indicate the mobility of the excavator and its walking ability. It can be reflected in the samples of various manufacturers.

Gradeability

Gradeability is the ability to climb, descend, or stop on a firm, level slope.

Two representation methods: angle, percentage

improving capability

Lift capacity refers to the lesser of the rated stable lift capacity or the rated hydraulic lift capacity.

Rated stable lift capacity: 75% of tipping load

Rated hydraulic lift capacity: 87% hydraulic lift capacity

Swing speed

The slewing speed refers to the average maximum speed that the excavator can achieve during stable slewing when the excavator is unloaded.

This means that the defined slew speed is neither the slew speed at start-up nor the slew speed during braking; that is, not the slew speed for acceleration or deceleration. For general excavation work, when the excavator works in the range of 0° to 180°, the slewing motor accelerates or decelerates, and when it turns to the range of 270° to 360°, the slewing speed becomes stable.

Therefore, in actual excavation work, the rotation speed defined above is unrealistic. That is, the required actual swing performance is acceleration/deceleration expressed in terms of swing torque.

engine power

Gross horsepower refers to the power output measured at the engine flywheel without power-consuming accessories such as mufflers, fans, alternators and air filters.

Net horsepower refers to the output power measured at the flywheel of the engine with all power-consuming accessories such as mufflers, fans, alternators and air cleaners installed.

Determination of noise

The main source of excavator noise comes from the engine.

Two kinds of noise: noise measurement at the operator's ears, noise measurement around the machine.