Process equipment industry product design 500 Taboo (2
One, to improve the strength and stiffness of the structure design
Avoid stress points and support points are too far away
Avoid the cantilever structure or reduce the length of the cantilever
Do not ignore the beneficial effects of the working load.
Parts subject to vibration load to avoid friction force
Avoid unbalanced forces in the body.
Avoid considering only a single transmission path
The influence of part deformation on the stress distribution at work is not ignored.
Avoid large tensile stress of cast iron parts
Avoid bending stress of the thin rod
Part of the impact load to avoid just spend a large
Stress free parts to avoid surface too rough or scratches
Residual tensile stress should be avoided on the surface of the affected parts
The variable load parts should avoid or reduce the stress concentration
Avoid affecting the strength of the local structure is too close
The deformation direction of pre deformation and working load is avoided.
The pulley of the wire rope and the diameter of the drum can not be too small.
Avoid wire rope bending too much, especially pay attention to avoid repeated bending
Lifting wire rope and the drum connection to keep a margin
Intermediate parts that can not be transmitted should be avoided as far as possible.
As far as possible to avoid the additional force generated when the axis misalignment
Try to reduce the force on the ground
Two, improve the wear resistance of structural design
Avoid the same material as the sliding friction pair
Avoid white alloy wear layer thickness is too large
To avoid the requirement for improving the wear resistance of the parts and the whole parts.
Avoid large parts of local wear and tear and lead to the entire parts scrapped
As with the white metal bearing liner, and bearing structure design should pay attention to the choice of bearing materials
Adequate supply of lubricant, full of working face
Lubricating oil tank can not be too small
Do not allow the filter to filter out the additives in the lubricant.
The size, position and shape of the oil groove of the sliding bearing should be reasonable.
Rolling bearings to join the amount of grease should not be too much
For parts of the easy to wear surface to increase a certain amount of wear allowance
Pay attention to the adjustment of parts after wear
The speed and pressure difference between points on the same contact surface should be small.
Dust prevention device to prevent wear debris
Avoid step wear
Contact type oil seal can not be used for sliding bearing
The easy to wear parts should be protected
The structure of automatic compensation for wear parts can be adopted.
Three, improve the accuracy of the structure design
Try not to use the structure of the program does not meet the Abbe principle
The mutual superposition of the error of the wear quantity is avoided.
To avoid the processing error and the amount of wear overlap each other
The driving force acting point of the guide rail should be on the center of the friction force of the two rail, so that the moment of friction between the two guide rails is balanced.
For the higher precision of the guide rail, it is not suitable to use a small amount of ball support
In the gear transmission chain, the final drive ratio should be the maximum.
The number of screw nut is not too small.
The axial movement of the spiral bearing must be strictly limited.
Avoid unreasonable bearing accuracy
Avoid unreasonable configuration of bearing radial vibration
To avoid the influence of the rolling guide rail precision
When the push rod and the guide path between the gap is too large, should adopt the sine mechanism, should not use tangent mechanism
High precision sine mechanism than tangent mechanism
Four, considering the structural design of human machine
Reasonable selection of operating posture
The height of the equipment and the proportion of the human body size should be reasonable.
Reasonable arrangement and adjustment to enhance the applicability of equipment
Mechanical manipulation, control and display shall be arranged at the most reasonable position in front of the operator.
The display device is in a reasonable form.
On the dashboard of the lettering should be legible
Knob size, shape to be reasonable
Keys should be easy to operate
Operating handle the required force and the range of activities should not be too large
The shape of the handle is easy to operate and force.
The reasonable design of the shape and size of the seat
Reasonable design of seat materials and elastic
May not have too much noise in the working environment
Operating site light illumination shall not be too low
Five, considering the heat, corrosion, noise and other structural design
To avoid the use of low efficiency of mechanical structure
Lubricating oil tank size should be large enough
The return fluid of the shunt system must be cooled.
To avoid high pressure vessels and pipes in the blazing sun
Part of the parts exposed to high temperature, such as rubber, polyethylene plastic manufacturing
The inside of the box parts of precision machinery should not be arranged in the tank, so as to avoid heat distortion.
For longer mechanical parts, it is considered that the temperature change can be changed when the temperature changes.
Hardened material operating temperature can not be too high
Avoid the condensation of moisture caused by high pressure valve
Large thermal expansion of the box can be in the center of support
The flange connected with the bolt is connected with the pipe, and when the sun is irradiated by the sunlight, the temperature and the elongation of the two sides are different.
The structure of the contact with the corrosive medium should avoid the slit.
The liquid in the container should be removed.
Pay attention to avoid the mechanical and chemical wear of the contact surface between the shaft and the hub.
Screw structure to avoid corrosion
When the connection between the steel pipe and the copper pipe, it is easy to produce electrochemical corrosion, and can arrange a section of pipe to be replaced regularly.
Avoid the structure of easy to be corroded.
Attention to the impact of the heat exchanger pipeline to avoid fretting wear
Reduce or avoidImpact and collision free of moving parts to reduce noise.
High speed rotor must be balanced
Impact parts quality should not be too small
In order to absorb vibration, parts should have strong damping
Six, casting structure design
Parting surface to be simple
Avoiding inner concave on the surface of the casting
Surface convex sets as far as possible
Outside surface of large castings should not have small protruding part.
Structure for improving obstruction of a mold
Avoid larger and thinner levels.
Avoid the shape of the larger internal stress
To prevent the deviation of the pattern of the appearance of adverse effects
Easy to take off the core structure
Parting surface should be as little as possible
Casting wall thickness to uniform
The wall thickness is uniform with the strengthening rib.
Consideration of solidification sequence design of casting wall thickness
The inner wall thickness should be less than the outer wall thickness
Casting wall thickness should be gradually transition
Two when the intersection angle should not be too small
The inner cavity of the casting should facilitate the making of core.
Do not use or less core support
As far as possible without type core
The hole edge of the casting should be raised.
Casting structure should be conducive to the removal of core sand
Core design should help to improve the quality of castings.
The hole of the casting is as close as possible.
Reasonable arrangement of strengthening rib
Ensure free shrinkage of castings to avoid defects.
Attention to the force of rib
The structure stability should be considered.
Remove unnecessary fillet
To be small, to be simple.
Pay attention to the reasonable strength and support of castings.
Seven, forging and stamping parts structure design
Free forging parts should be avoided in the shape of a cone and wedge
To simplify the intersection form
Avoid rib
Free forgings should not be designed with complex convex sets.
Free forging parts inside the boss should not fork
The dimension of the parting surface of the die forging shall be the maximum size of the parts, and the parting surface shall be flat.
The shape of die forging should be symmetrical.
Die forging should have proper fillet radius.
Die forging should be suitable for mold release
Die forging should be as simple as possible.
The shape of stamping parts should be as symmetrical as possible.
Part of the local width should not be too narrow
The depth and shape of the convex platform and the hole should be required.
Stamping parts design should consider the material
Stamping parts should avoid large plane
To avoid wrinkling at the bend.
Pay attention to design slope
Prevent Kong Bianxing
Simplified expanded graph
Note that support should not be too thin
A thin plate bending member must have a notch at the bend.
Pressure rib can increase the stiffness but has the direction
Drawing simple shapes
Flange drawing parts should be uniform
The structure can be simplified by using the technique of incision
Stamping part dimension should consider die wear
Stamping part size to consider stamping process
Eight, welding parts of the structure of the blank
Reasonable design appearance
Reduce scrap
Using a set of cutting
Weld seam should not be arranged at the section turning point
Welding parts can not disregard their own characteristics, simple imitation castings
Section shape should be conducive to reduce the deformation and stress concentration
Correct choice of weld position
Do not let the welding affected areas are too close
Pay attention to the stress of the welding seam
Reinforced rib layout to be reasonable
Reduce the stress of the welding seam
Reduced thermal deformation
Rational use of profiles, simplified welding process
Welds shall be avoided to the machined surface
Consider gas diffusion
Stamping parts can be used instead of the processing parts
Using sheet metal bending to reduce weld
Nine, mechanical processing parts structure design
Pay attention to reducing the blank size
Processing surface and processing surface should not be flat
Reduce the length of the machined surface
Different processing accuracy of the surface to be separated
Change the shape of the parts to the assembly for easy processing
Avoid unnecessary accuracy requirements.
Tool is easy to enter or exit the machined surface
Avoid processing closed space
To avoid the tool can not be close to the workpiece
Can not be used with the tool shape is not suitable for the shape of the parts
To take into account the effects of casting errors
Avoid multiple parts processing
Complex machining surfaces should be designed on the outer surface rather than on the inner surface.
Avoid complex shape parts chamfering
Must avoid the stop of the non circular parts.
Avoid unnecessary processing
Part structure can not be clamped.
To avoid the parts structure without surface measurement
Avoid shock and vibration in the process
Avoid drilling on inclined planes
The bottom hole don't produce local not through
Reducing the number of cutting tools used in machining the same parts
Avoid multiple fixation in machining
Pay attention to the possibility of machining parts with multiple parts at a time.
Ten, heat treatment and surface treatment of structural design
To avoid the parts of the wall thickness of the gap
Requirements of high hardness parts (overall quenching treatment) size can not be too large
We should avoid sharp and sudden change in size
Avoid using asymmetric structures
Avoid open parts quenching
Avoid quenching parts structure is too complex
To avoid the parts stiffness is too low, resulting in quenching deformation
Partial quenching is used to reduce the deformation
Avoid too close to the edge of the hole parts
High frequency quenching gear blockThere should be a certain distance between the two gears
Plating steel parts surface can not be too rough
The coating thickness should be considered in the mechanical process of the electroplating of the parts.
Pay attention to the reflection of the electroplating part is not suitable for some working conditions
Eleven, considering the mechanical structure design of assembly and maintenance
When removing a part, avoid other parts to be removed
Avoid loading two mating surfaces at the same time
To leave the necessary operating space for the disassembly and assembly parts
To avoid the error caused by the normal operation of the installation
Use special structure to avoid wrong installation
Simplified assembly process using symmetric structure
Flexible sleeve installation to have the boot section
Difficult to see the matching parts, there must be a guide section
In order to facilitate the installation of the mechanical hand, the clamping buckle or the internal locking structure is adopted.
Fastener head should have a smooth straight edge to pick up
The parts installation site should have the necessary chamfer
Automatic feeding mechanism for feeding parts, should avoid lap winding
Simplified assembly movement mode
Reasonable division of components for a machine