The excavator turns on the air conditioner, and the water temperature is high.

Generally, the cooling fans of excavators are suction type, so let's take suction type as an example. When the engine is working, the crankshaft of the engine drives the fan to rotate through a belt (some models are rigidly connected), which sucks the cold air outside the excavator door into the engine, blows it to the engine body, and then discharges it from the cooling hole at the rear of the engine near the upper part of the hydraulic oil tank.

During this cycle, cold air needs to pass through radiator water tank, hydraulic oil radiator, air conditioner radiator, vehicle with intercooling and supercharging, intercooling radiator, take away the heat of these radiators, then blow them to the engine, take away part of the heat of the engine body from front to back, and finally discharge them from the engine compartment.

In this air circulation process, the sealing of the engine compartment is very important, and the air flow in the sealed engine compartment can flow according to the designed path. If the engine compartment sealing sleeve is damaged or the engine hood is opened, the air sucked by the fan will easily form a vortex in the engine compartment, and the air cannot reach the rear of the engine, which will affect the heat dissipation effect. At present, many users find that the engine likes to open the hood to dissipate heat after high temperature, but this is actually a misunderstanding, which will lead to the volcano getting hotter and hotter because of the lack of heat vents.

Let's talk about the circulation of antifreeze, which is divided into large circulation and small circulation, which is converted by the thermostat. When the engine is started, the antifreeze temperature is low, which can't reach the normal working temperature of the engine. At this time, the thermostat is in the closed state, and the antifreeze only circulates inside the engine under the action of the water pump, without passing through the radiator of the water tank. When the temperature of antifreeze rises slowly and reaches the critical value of the thermostat, the thermostat will slowly open and gradually turn into a large cycle. That is, antifreeze takes away heat through the engine waterway and then returns to the upper part of the water tank. After heat dissipation, it enters the engine through the pipeline at the lower part of the water tank, and so on, taking away the heat of the engine.

Understand the air circulation and anti-freezing circulation of the excavator engine. Let's analyze the solution of high water temperature after the excavator turns on the air conditioner.

Many users said that when the air conditioner is turned on in summer, the water temperature of their excavators will "rub" up and get hot immediately. Then the air conditioner turned off and the water temperature gradually dropped. The air conditioner is not turned on in summer, and the driver does not erupt when he enters the steamer.

In fact, for this kind of excavator, the problem of high water temperature already exists when the air conditioner is not turned on, but it is not particularly serious. The critical value of antifreeze alarm has not been reached. The load of the air-conditioning engine increases, and the influence of the air-conditioning radiator leads to high engine temperature. We can analyze this process in detail.

Take a 20-ton excavator as an example. The rated power of this tonnage excavator is generally around 1 10KW, and the power required by the air-conditioning compressor is around 4.5KW From the data point of view, it should have little influence on the load of an air-conditioning compressor when the engine works, but this is not the case, because the excavator with high engine temperature has been used for a certain number of years, at this stage, the engine power of the excavator will decrease due to wear, and so will the air-conditioning compressor.

We can understand that under one working condition, the 5-grid throttle can work normally. At this time, if the air-conditioning compressor is involved in the work, the engine load will increase and the rotational speed will decrease, resulting in a slight "truck" phenomenon, but at this time, the oil supply of the engine does not decrease with the decrease of the rotational speed, and the calorific value of the engine is basically unchanged. However, due to the decrease of rotational speed, the pump speed and fan speed will also decrease, and the circulation speed of antifreeze will also decrease. At the same time, the air intake of the fan decreases, and the heat dissipation efficiency of the radiator of the water tank decreases. Coupled with the influence of air conditioner radiator, the temperature of engine antifreeze rises at this time, even reaching the temperature alarm of antifreeze.

So how should this situation be solved? The short-term solution is to increase the throttle of the engine to increase its current output power and meet the power demand for driving the air-conditioning compressor. The second method is to improve the engine cooling system and improve the cooling efficiency.

The latest and most comprehensive job-seeking information of construction machinery drivers in China, and the job-seeking information of excavators and loaders is all in the driver market!