Problems to be paid attention to in stage mechanical design

In the design of stage machinery, in the implementation of the traditional methods, the effective new ideas and new ideas should be continuously absorbed, so that the stage mechanical design work is constantly improved and perfected. There are some problems that are easy to be neglected or neglected in the design process. line array

1. Calculation of equipment base connection

The connection between the equipment base and the foundation or rack is a very important safety part. It must not be overlooked and should be calculated in detail. The calculation should take into account the force characteristics (tilting torque), tightening requirements (pre tight, no slit, no crushing), pretightening force and single bolt calculation, tightening torque and pretightening force control and bolt strength level and material selection (8.8 and above, but 10.9 and above alloy steel bolts are less or not).

2. Bulging bolt

Because the stage mechanical design is often lagging behind the civil design, sometimes it can not provide the blueprint, so that the construction structure has been constructed, the bolt bolt can only be used as the connection between the equipment and the building structure. Therefore, it is necessary to have a thorough understanding of the installation, installation and failure type of the bolt bolt, and should be fully aware of the product situation and application scope and the matters needing attention.

3. Chemical bolts

For the same reason, the use of chemical bolts is also increasing, because the use of less, less experience in the past, the need to use the method of careful understanding, rational use. Chemical bolts are used to bond screw and hole wall by synthetic resin mortar, resist pulling by the joint force and mechanical bite force between the concrete and the concrete, and resist the shearing by the bolt itself, so as to achieve the effect of fixing the component and improving the bearing capacity of the component. As the adhesion ability depends on different chemical adhesives, the mechanical indexes (screw diameter, hole diameter, anchorage depth, design pulling force, etc.) are calculated according to the information provided by the manufacturer. At the same time, we must strictly control the construction procedures and the quality of construction. In drilling, hole cleaning, glue injection, plugging, gel hardening and other procedures, we should also implement the regulations in accordance with the provisions of the production plant.

4. Precautions for the design of transmission parts

Design principle: the structure should make the force reasonable; reduce stress concentration; strength and rigidity; corrosion resistance and high temperature resistance; good processing technology; easy installation and disassembly.

Material: use less ordinary carbon steel (Q235 or Q275 etc.) as far as possible, and give priority to high quality carbon steel or low alloy steel (35, 45, 40Cr, 45Mn2, 40MnB, 35CrMo, 40CrNiMo and other quenched and tempered steel). Special attention should be paid to the surface treatment of the important shaft (the highest surface stress, the friction and impact), the heat treatment technology and the surface hardness. Attention should be paid to checking the size and structure of the stress and fatigue damage location of the parts such as fillet, chamfer, withdrawal slot, small hole, and through hole.

5. On the organization of lifting (Juan Yang)

Because the lifting (Juan Yang) mechanism used in the stage machinery is derived from the crane equipment, it is necessary to understand the effect of the level and work grade (M4, M5 or M6) and its influence on the selection of the element in the crane design standard; to pay attention to the strength of the wire rope and the strength of the rope fixed joint (such as the efficiency of bonding of aluminum alloy to the joint and the standard brick. " When using the spiral buckle of the rigging, we should pay attention to the difference between the safety load of the product and the minimum breaking load, and the strength grade of the life series according to the provisions of the first class.

6. The diameter of the drum

The standard tank is recommended because of the unclear requirements for standard trench (deep groove and standard tank) in the standard. Because the single point crane does not use rotating wire rope, the diameter of the drum should be selected according to the working mechanism of a higher grade.

The safety of the stage machinery must start from the design (and mainly guaranteed by the design), which runs through the various stages of manufacturing, installation, commissioning, use and maintenance.

(1) design: strict requirements, strict implementation of the design procedures (especially design, input, output, etc.), strict design management system; careful design, accurate calculation, delicate drawing; careful review, careful treatment of feedback problems, detailed design tasks, and special attention to details (sometimes details determine success or failure);

(2) construction: grasp the key points of technology, grasp the key points of quality, grasp the progress control points, and grasp the easy leakage points.

(3) testing and debugging: adhere to the principle of first controlling the equipment, first loading after the load, first low speed, high speed and first single machine after marshalling.

(4) operation and operation: adhere to the principle and persistence of the operator's direct movement of the equipment.

Under the bad conditions, we should reduce the operating principle of the parameters, insist on the on-site inspection and pre commissioning of the equipment. On the basis of careful control of all the above links, coupled with perfect management system and operation maintenance system, stage machinery and equipment can make people run confidently.