How to Warm Up the Self Loading Concrete Truck

 The usual way to warm up the self loading concrete truck is finished when the engine is running. After the hydraulic pump works passively for a period of time, the temperature of the hydraulic oil rises to the specified value, the viscosity of the hydraulic oil reaches the normal working state, and the preheating of the self loading transit mixer is finished.

This recognized preheating operation method seems simple, but it is not. If the preheating operation of the self loading mixer is carried out in the correct state, the wear and failure rate of the hydraulic system of the car body can be effectively reduced. On the contrary, incorrect warm-up behavior will inevitably increase the wear and tear of the equipment.

In the early stage of warm-up, the main oil pump of the self loading concrete mixer must keep running dry. There are generally four types of hydraulic pumps installed in the hydraulic system on self-loading mixer trucks, namely the main oil pump, balance pressure pump, mixing pump and boom pump. In terms of the working principle of the hydraulic pump, except for the mixing pump which belongs to the gear pump, the other three pumps belong to the swash plate plunger pump. In comparison, the performance of the swash plate plunger pump is better than that of the gear pump, and the precision is higher and the price is higher, so more attention should be paid to it.

For self loading concrete mixer truck with different working principles, the operation method of letting the main oil pump run dry is different. In the current common concrete pumping hydraulic system, there are two main types - open system and closed system.

For the self-loading mixer truck of the open system, the pumping displacement can be set at the "zero" position when the top-mounted power take-off is turned on. Depending on the brand and age of your self-loading mixer, the setup method may vary slightly.

For a self propelled concrete mixer with a closed system, the method is relatively simple, that is, when the power take-off of the body is turned on, the pumping is kept in a stopped state.

In the later stage of warm-up, the displacement of the main oil pump gradually increases. During the idling process of the hydraulic pump of the self propelled concrete mixer, the bearings, oil distribution plate and other components will inevitably heat up due to motion friction. The heat is gradually transferred to the surrounding hydraulic oil, so that the temperature of the hydraulic oil gradually increases and the viscosity gradually decreases.

After a period of time, the swash plate of the hydraulic pump can be adjusted to a small angle to make the hydraulic oil flow, so that the hydraulic oil with a higher temperature is sent into the hydraulic circuit.

Due to convection and conduction, the oil in the hydraulic motor and pipeline gradually heats up. The preheating work is not successfully completed until the hydraulic oil of the entire pumping system reaches the working temperature.

Original Source: https://www.self-loading-mixer.com/a/how-to-warm-up-the-self-loading-concrete-truck.html