Structural characteristics of hydraulic lock:
Bidirectional hydraulic lock is a double pneumatic check valve that can be used together (see Figure 1). It is usually used in load-bearing hydraulic cylinder or oil circuit to prevent the hydraulic cylinder or motor from falling under heavy load. During operation, fuel must be supplied to another road. Open the check valve through the internal control oil circuit, connect the oil circuit, and operate the hydraulic cylinder or motor.
Bidirectional hydraulic lock and balance valve can be used as blocking parts in some cases, to ensure that the working device will not fall due to its own weight and other external factors, speeding or pulling rope.
However, under certain speed load conditions, they cannot be used interchangeably. Here are some views on the two product structures of loader repair manufacturers.
Due to the structure of the product itself, during the movement of the hydraulic cylinder, due to the weight of the load, there is an instantaneous pressure loss in the main working room, a vacuum is generated, the check valve is closed, and then the oil supply continues to increase the pressure in the working room. Open the check valve. Due to frequent opening and closing actions, the load will cause large shocks and vibrations during the descent. Therefore, bidirectional hydraulic locks are generally not recommended for high-speed heavy-duty operations, but are generally used for longer support times and movements. Low speed latch circuit.
Balancing valve structure characteristics:
Balance valve, also known as speed limit lock (see Figure 2), is an externally controlled internal discharge type one-way sequence valve used by one-way valves and sequence valves. The hydraulic circuit can lock the hydraulic cylinder or motor. The oil in the oil circuit prevents the hydraulic cylinder or motor from falling due to the weight of the load, and at this time it acts as a lock. When the hydraulic cylinder or motor needs to move, the movement is achieved by transferring the liquid to another oil passage and simultaneously controlling the sequence valve to open the circuit through the internal valve of the balancing valve. Since the sequence valve itself is different from the structure of the two-way hydraulic lock, it can be said that a certain back pressure is established in the workpiece circuit during operation. Therefore, the main work of the hydraulic cylinder or the motor generates a negative pressure. Due to the self-weight overspeed drop, there is no impact Vibration is like a two-way hydraulic lock.
Therefore, the balance valve is generally used for high-speed heavy load and circuit, it has certain speed stability requirements.
Combining the structural analysis of balance valve and two-way hydraulic lock, the author suggests:
In the case of low speed light load and low speed stability requirements, in order to reduce costs, you can use a two-way hydraulic lock as a circuit lock. In the case of high speed and heavy load, especially for speed stability requirements, the balancing valve must be used as a blocking component. The two-way hydraulic lock must be selected instead of reducing costs. Otherwise, it will cause greater losses.
