Jiaozuo brake

The luffing mechanism is the main working mechanism of a boom type crane, used to change the amplitude of the crane, that is, to change the horizontal distance from the center of the hook (or grab) to the axis of the crane's rotation center, in order to adapt to the loading and unloading of items by the crane under different conditions. It adopts an internal high-precision, hard tooth surface planetary gear reducer, which is characterized by smooth operation, high transmission efficiency, compact structure, convenient installation, high bearing capacity, long service life, and unparalleled advantages compared to cycloidal pinwheel and worm gear worm Xuan deceleration and amplitude changing mechanisms. It is an ideal replacement product for large, medium, and small crane amplitude changing mechanisms. According to its implementation method, the luffing mechanism can be divided into two types: the operating trolley type luffing and the arm type luffing, which can be further divided into the telescopic arm type and the swinging arm type; According to job requirements, it can be divided into non working amplitude and working amplitude; According to performance requirements, it can be divided into unbalanced and balanced amplitudes. The crane brake is installed on the rotating shaft of the electric motor to brake the operation of the motor, so that its operation or lifting mechanism can accurately and reliably stop at the predetermined position. Commonly used are spring type short stroke electromagnetic double brake shoe brakes, abbreviated as short stroke brakes (single-phase brakes); Spring type long stroke electromagnetic double brake shoe brake, abbreviated as long stroke brake (three-phase brake); There are three types of hydraulic push rod dual brake shoe brakes, abbreviated as push rod brakes.

The operating trolley type luffing system relies on the operation of a load-bearing trolley along a horizontal arm track to achieve luffing, such as the operating trolley of a shore container crane. The swing arm type luffing system relies on the swing of the arm frame around its hinge axis in the vertical plane to achieve luffing. It is a common luffing method in port cranes, such as the luffing mechanism of portal cranes.

Non working amplitude change refers to amplitude change without load, which is characterized by less frequency of amplitude change and lower speed of amplitude change. Working range change refers to load range change, which is characterized by frequent and fast range change as the main component of each working cycle of the crane. This range change method is beneficial for improving the mobility of the crane and expanding its service range. Analyze the reasons for the generation of dynamic load and the factors affecting dynamic load during the braking process of the rack driven variable amplitude mechanism, discuss the motion during the clearance elimination stage of the mechanism's tooth side and the impact vibration response of the mechanism during the collision stage, and propose a calculation method for the large dynamic load during the braking of the variable amplitude mechanism

Balanced luffing refers to the process in which the center of gravity of an object can move along a horizontal or approximate horizontal line during the luffing process. The self weight of the arm frame (or arm frame system) is balanced by a movable balance weight, and the combined center of gravity of the two is moved or fixed at a point along the horizontal or approximate horizontal line during the luffing process. The center of gravity of the boom (or boom system) can also be moved along or near the horizontal line during the amplitude change process without relying on the structural characteristics of the boom system itself through the use of movable counterweights. Balanced luffing is often used in working luffing mechanisms. Non balanced luffing refers to the process of raising and lowering the center of gravity of the swinging arm frame and the object during the luffing process. When the amplitude is reduced, it consumes a large amount of driving power, while when the amplitude is increased, potential energy is released, which affects its performance. Non balanced luffing is mainly used for non working luffing mechanisms.

The speed of the working luffing mechanism is determined based on its purpose and lifting capacity. When used for loading and unloading operations, the luffing speed is set at 40-90 m/min; When used for installation work, it is taken as 10-35 m/min. When the lifting capacity is large, take the lower value

Calculation principles of variable amplitude drive mechanism

1. Selection of electric motors

The motor of the variable amplitude mechanism is calculated based on the maximum value of the root mean square equivalent resistance moment under various working conditions under normal working conditions, and then the motor is preliminarily selected based on the equivalent power and the continuity of the mechanism's connection. Then verify the overload and heating of the motor.

The equivalent luffing resistance torque is the root mean square value calculated based on the luffing resistance torque at different amplitude positions and the luffing time in the corresponding amplitude range during the entire luffing process of the corresponding lifting weight under normal working conditions. The variable amplitude resistance moment is generated by the unbalanced lifting load and the self weight load of the boom system, the wind force acting on the boom system, the horizontal force caused by the swing angle of the lifting rope, the inertia force of the boom system, the slope resistance caused by the crane tilt, and the frictional resistance of the boom system during variable amplitude.

2. Selection of brakes

Like the lifting mechanism, the brake of the luffing mechanism should be of the normally closed type. For the balanced luffing mechanism, the braking Factor of safety is 1.25 under working condition; Take 1.15 for non working conditions. The main unbalanced luffing mechanism shall be equipped with two support brakes, and the selection principle of its braking Factor of safety is the same as that of the lifting mechanism.

3. Force calculation of parts

The comprehensively considered variable amplitude resistance is converted to a calculated part. Due to the variation of amplitude change resistance at different amplitude positions throughout the entire amplitude change process, these resistance should be calculated for several amplitude positions, and the larger one should be compared as the force acting on the component. 6 models of brakes

YWZ, YWZ3, YWZ4, YWZ5, YWZ8, YWZ10, YWZ9, YWZ13, YW series electric hydraulic brake electromagnetic failure protection disc brake:

3SE; 4SE; 5SE; 450SE; 56SE; 560SE; 561SE; ST1SE; ST2SE

Hydraulic fail safe disc brake:

3SH; 4SH; 5SH; 450SH; ST1SH; ST2SH; ST3SH; ST4SH; ST5SH; ST10SH; ST16SH; ST25SH; 904SH;

ST40SH

Pneumatic fail safe disc brake:

3SP; 4SP; 5SP; 450SP

Hydraulic direct acting disc brake:

ADH60; ADH90; ADH120; DADH75; DADH80; DADH90; DADH120; DADH195; DADH350

Pneumatic direct acting disc brake:

ADP60M; ADP61M; ADP62M

Pneumatic caliper disc brake

CQPL12.7A-A; CQPL12.7A-B; CQPL12.7B; QPL12.7A-A; QPL12.7A-B; QPL12.7-A; QPL12.7-B;

QP30-D; QP25.4-D; CQP30-D; CQP25.4-D; PDA5; PDA10; PDB5; PDB10; PDB19; PDC5; PDC10

Electromagnetic caliper disc brake:

DCPZ12.7-250; DCPZ12.7-300; DCPZ12.7-400

Hydraulic caliper disc brake:

SB (YQP) 50; SB (YQP) 100; SB (YQP) 160; SB (YQP) 250; SB (YQP) 315; SB (YQP) 400;

SBD safety brake:

SBD100-A; SBD125-A; SBD160-A; SBD200-A; SBD250-A; SBD-B; SBD160-B; SBD250-C; SBD365-C; SBD425-C; SBD80-B; SBD160-B; SBD250-C; SBD365-C; SBD425-C; SBD120-D; SBD240-DST, SBD, SH images