In winter, when using a diesel engine for a truck-mounted crane, in order to achieve fuel savings and reduce energy consumption, installing a preheating device on the diesel engine can be a highly effective measure. Preheating is carried out through the exhaust pipe, which serves to increase the temperature of diesel fuel and reduce its viscosity. When the preheated diesel enters the diesel pump, it exhibits a better atomization effect, ensuring sufficient combustion and resulting in a significant reduction in fuel consumption. There are two specific methods for implementing this preheating process.
Single-layer pipe preheating.
Drill 11-millimeter holes at both ends of the diesel engine exhaust branch pipe. This allows the preheating pipe to pass through the exhaust branch pipe. Both ends of the oil pipe are welded with oil pipe joint screws. One end is connected to the oil outlet pipe of the diesel engine fine filter.
Let’s explore this method in more detail. The single-layer pipe preheating method is a relatively simple and cost-effective way to increase the temperature of diesel fuel. By passing the preheating pipe through the exhaust branch pipe, heat from the exhaust gases is transferred to the diesel fuel flowing through the pipe. This heat transfer process raises the temperature of the diesel, reducing its viscosity and improving its flow properties. As a result, when the preheated diesel enters the diesel pump, it can be atomized more easily, leading to better combustion and reduced fuel consumption.
The choice of a 11-millimeter hole size is important as it needs to be large enough to allow the preheating pipe to pass through without causing excessive restriction to the exhaust flow. The welded oil pipe joint screws ensure a secure connection between the preheating pipe and the diesel engine’s fine filter outlet pipe. This connection allows the preheated diesel to flow smoothly from the preheating pipe into the fuel delivery system.
Using single-layer pipe preheating can generally increase the oil temperature to 56-75°C. This temperature range is crucial for achieving optimal fuel savings. At this temperature, the diesel fuel’s viscosity is significantly reduced, allowing it to flow more easily through the fuel system and atomize better in the combustion chamber. This improved atomization leads to more complete combustion, which in turn reduces fuel consumption by approximately 5-6%.
However, it is important to note that the effectiveness of single-layer pipe preheating depends on several factors. The heat transfer efficiency between the exhaust gases and the preheating pipe can be affected by the insulation of the pipe, the proximity of the pipe to the exhaust source, and the flow rate of the exhaust gases. Additionally, the quality of the materials used for the preheating pipe and the welds can impact its durability and performance.
Double-layer pipe preheating.
Drill 17-millimeter-diameter holes at both ends of the diesel engine exhaust pipe. Insert an iron pipe with a length of 500 millimeters. The iron pipe is firmly welded to the exhaust branch pipe, and then insert the preheating pipe into the iron pipe. Both ends of the oil pipe are welded with oil pipe joint screws. One end is connected to the oil outlet pipe of the fuel fine filter, and the other end is connected to the oil inlet pipe of the fuel pump.
The double-layer pipe preheating method offers an enhanced level of heat transfer compared to the single-layer pipe method. By using an iron pipe inserted into the exhaust pipe and then placing the preheating pipe inside the iron pipe, a greater amount of heat can be transferred to the diesel fuel. The larger 17-millimeter-diameter holes are necessary to accommodate the iron pipe and ensure proper exhaust flow.
The length of the iron pipe, 500 millimeters, is chosen to provide sufficient contact time between the exhaust gases and the preheating pipe. This longer contact time allows for more efficient heat transfer and results in a higher temperature increase for the diesel fuel. The firm welding of the iron pipe to the exhaust branch pipe ensures a stable connection and prevents any leaks or disruptions in the heat transfer process.
Similar to the single-layer pipe method, the oil pipe joint screws on both ends of the preheating pipe ensure a secure connection to the fuel fine filter outlet pipe and the fuel pump inlet pipe. This allows the preheated diesel to flow smoothly through the fuel system.
Using double-layer pipe preheating can generally increase the diesel temperature to 65°C. This higher temperature further reduces the viscosity of the diesel fuel and improves its atomization and combustion efficiency. As a result, fuel consumption can be reduced by 6-10%, which is a significant improvement over the single-layer pipe preheating method.
It should be noted that the optimal temperature for diesel preheating is 65-75°C. If the temperature is too low, the fuel-saving effect will be poor. At temperatures below this range, the diesel fuel’s viscosity remains relatively high, and its atomization and combustion may not be significantly improved. This can lead to suboptimal engine performance and higher fuel consumption.
On the other hand, if the temperature is too high, wear on the engine components can be aggravated. Excessive heat can cause damage to the fuel injectors, piston rings, and other engine parts. This can lead to reduced engine life and increased maintenance costs. Therefore, when installing a preheating device for a truck-mounted crane diesel engine, it is crucial to pay close attention to the temperature requirements and ensure that the preheating system is properly calibrated and regulated.
To achieve the optimal preheating temperature, several factors need to be considered. The design and installation of the preheating system should be carefully planned to ensure efficient heat transfer without overheating the diesel fuel. The insulation of the preheating pipes and the exhaust system can help maintain the desired temperature and prevent heat loss. Additionally, the use of temperature sensors and control devices can help monitor and regulate the preheating process to ensure that the diesel fuel reaches the optimal temperature range.
In conclusion, implementing preheating measures for diesel engines in truck-mounted cranes can be an effective way to save fuel and reduce energy consumption. The single-layer and double-layer pipe preheating methods offer different levels of heat transfer and fuel savings. However, it is essential to pay attention to the optimal temperature range for diesel preheating to achieve the best results while avoiding excessive wear on the engine components. By carefully installing and maintaining a preheating device, truck-mounted crane operators can improve the efficiency and performance of their diesel engines while reducing operating costs.
