1. Small and medium-sized pulleys are selected as the pulley blank, and HT 150 is mostly used for manufacturing, and its blank is generally cast in sand mold, and it is formed by hand when the production batch is small; Machine modeling can be used when the production batch is large; For pulleys with large structural dimensions, steel plates can be used to weld blanks to reduce the weight.
2. The blank of sprocket is mostly steel, and forgings are the most commonly used. Free forging is used for single piece and small batch production; Die forging is used when the production batch is large; New product trial production or parts repair, profiles can be used; The driven sprocket with more than 50 teeth can also be cast iron with strength higher than HT 150 and cast in sand mold. The modeling method depends on the production batch.
3. In the selection of steel gear cylindrical gear blank, if the size is small and the performance requirements are not high, hot rolled bar can be directly used. In addition, forging blanks are generally used. Free forging is used for gears with small production batch or large size; Die forging is used to produce a large number of small and medium-sized gears. For gears with large diameter and complex structure that are not easy to forge, cast steel blanks or welded combined blanks are used.
Question 2: What are the material classifications of box parts? What is the difference? If you know, please tell me, thank you. Better be more specific. Cast iron is generally used.
Brand HT200~HT400
Single pieces are sometimes welded with steel plates.
Specific conditions, such as aluminum-magnesium alloy for aircraft.
Specifically, check the metal material manual.
Question 3: What kind of machine tool should be used to process box parts? Machine tools should be selected according to the machining accuracy, purpose and size of the box, including gearbox, electric control box and explosion-proof box. The technical requirements of the gearbox are relatively high, mainly the center distance of each gear and the joint surface of the box; Explosion-proof box is the flatness and smoothness (surface roughness) of explosion-proof surface. The commonly used equipment is CNC boring and milling machine, milling and boring machine and high-precision horizontal boring machine (brought back to the turntable). & gt
Question 4: Although the material of the gearbox on the drawing is HT200, the actual production may be inconsistent.
Question 5: What material is used for the cabinet? The whole cabinet has entered the homes of ordinary people today and has become an indispensable landscape for ordinary families. The whole cabinet mainly includes cabinet body, panel (door panel), table top and hardware. There are many kinds of cabinet materials, and the prices are different. How to choose your favorite cabinets, how to make the design reasonable, beautiful and practical, and how to avoid the trap in purchasing, you must do your homework.
Let's tear down the whole cabinet one by one;
First, the cabinet.
The vast majority of cabinets are particleboard, and very few are medium density boards. Particleboard is a kind of natural wood that is crushed into particles and pressed into plates. Its waterproof performance is better than that of MDF, and it is the main material of kitchen cabinets at present.
Particleboard classification:
According to the use, it is divided into grade A particleboard and grade B particleboard;
According to the structure of particleboard, it is divided into: a. single-layer particleboard; B. three-layer structure particleboard; C. particleboard with gradually changing structure; Oriented particleboard; E. waffle particleboard; F. molded particleboard;
According to the surface condition, it is divided into: unprocessed particleboard: a. sanded particleboard; B. dry particleboard. Veneered particleboard: a. impregnated paper veneered particleboard; B. decorative laminated veneer particleboard; C. veneer-faced particleboard; D, surface coating the particleboard; E. PVC veneer particleboard, etc. ;
The standard cabinet material adopts melamine particleboard (including imported kitchen cabinets). The main ingredient of melamine particleboard is to cut natural logs, crush them into small shapes with specifications, add environmental protection glue and refine them at high temperature and high pressure. Melamine board is made of colored paper pressed on a plain board at 600℃, and the environmental protection standard in China is 100 mg ≥ 40g. The lowest European standards E- 1, 100mg≥ 10, and E-O standard 100 mg ≥3. If it exceeds E-O, there will be no formaldehyde. The Lushuihe particleboard of Jilin Forest Industry Group is widely used by domestic manufacturers, and its quality has passed the European E- 1.
Characteristics of Lushuihe particleboard;
A. Pay attention to environmental protection, adopt high-tech environmental protection glue formula, and produce E 1 grade moisture-proof and environmental protection base materials that meet European standards.
B. Exquisite decorative paper is used, which has the characteristics of exquisite patterns and colors, clear texture and light fastness.
Characteristics of Ai Jia/Checkerboard Iger Particleboard;
The material is selected from several kinds of needles growing in cold regions of continental Europe. In order to make the board have good physical properties and reprocessability, a small amount of sawdust is mixed during the processing. Particleboard overcomes the shortcomings of natural wood and has stable physical properties. Therefore, particleboard is a kind of board made of natural logs through cutting, crushing and high temperature and high pressure, which is more suitable for furniture production and use. Aijiaban has a flat surface and is not easy to deform. It is also a kind of green environmental protection product, and the harmonious unity of appearance and function can perfectly reflect the excellent quality of the product.
medium density fiberboard
It is an artificial board made of wood fiber or other plant fiber and urea-formaldehyde resin or other suitable adhesive. Density board is easy to reprocess because of its softness and impact resistance. Poor moisture resistance. Good flatness, usually used for panel furniture and office furniture. Because the density board is easy to loosen after fastening, the strength of fastening after loosening is insufficient. Because of the good flatness of medium density, it is suitable for door panels and countertops. When used for box boards, it is limited in the process of assembly and fastening.
It should be noted that the thickness of the plate is mostly 16mm, and of course there are 18 mm, and the thicker the plate, the more expensive it is. Many people only care about door panels and countertops. In fact, there are patterns here. The advertisement is 18mm board, and the contract is changed to 16mm board. Many people didn't pay attention. The actual quality of cabinets should be considered: 1. Plate, 2 thickness and 3 edges. Edge sealing is very important, the thicker the better, the more durable it is, so that formaldehyde in the plate will not volatilize.
Second, the panel (or door)
The thickness of door panels is generally 18MM, and there are many kinds of materials.
1, solid wood board
It has the effect of returning to nature and simplicity, and the treatment of flower corners and the color of paint require high technology, which can better express the classical style. It should be noted that the so-called solid wood boards are not all solid wood. Its doorframe is made of solid wood, mainly cherry wood, walnut wood and oak. The door core adopts solid wood skin medium density board. Generally, the surface of solid wood is uneven and painted, so as to maintain the color and beautiful shape of logs. This can ensure the special visual effect of solid wood, and the combination of frame and core board can also ensure the strength of door panel. & gt
Question 6: What materials are commonly used for main parts (gears, shafts, boxes)? We always use 45 steel as shaft parts, and then adopt quenching and tempering treatment. Thank you for your adoption.
Question 7: What are the main technical requirements for processing box parts, such as accuracy and surface roughness, to ensure the rotary accuracy of bearings and shafts installed in holes?
The flatness and straightness of the plane are to ensure the contact stiffness of the contact surface after assembly and the positioning accuracy of the guide surface of the whole machine;
The position accuracy of hole system is the most important technical requirement of box parts, including the position accuracy of holes and holes. The main problems of surface machining of box parts are plane and hole. Its technical requirements are mainly reflected in three aspects: the size of the hole and the position accuracy between the hole and the plane.
Question 8: What are the structural characteristics and main technical requirements of box parts?
The box is the basic part of a machine or component, which assembles the shaft, sleeve, gear and other related parts in the machine or component into a whole, keeps their correct mutual positions, and transmits motion or power in a coordinated manner according to a certain transmission relationship. Therefore, the processing quality of the box will directly affect the accuracy, performance and life of the machine or parts.
Common box parts are: machine tool spindle box, machine tool feed box, gearbox, reducer, machine body and frame, etc. According to the different structural forms of box parts, it can be divided into integral boxes, as shown in Figure 8- 1A, B and D, and separate boxes, as shown in Figure 8-1c. The former is an integral casting process, which is difficult to process, but has high assembly accuracy; The latter can be manufactured separately, which is convenient for processing and assembly, but it increases the workload of assembly.
Although the box has various structural forms, it still has the same main characteristics: complex shape, thin and uneven wall, hollow interior, many parts to be machined, and difficult machining, including holes and planes with high precision requirements, and many fastening holes with low precision requirements. Therefore, the machining labor of box parts in general medium-sized machine tool plants accounts for about 15%~20% of the total processing capacity of products.
Main technical requirements
1. Shape accuracy and surface roughness of main plane
The main plane of the box is the assembly datum plane, which is often the positioning datum plane in the process of machining, so it is required to have high flatness and small surface roughness, otherwise it will directly affect the positioning accuracy in the process of machining the box, and affect the contact stiffness and mutual position accuracy of the box and the frame during the final assembly.
GeneRally, the flatness of the main plane of the box is 0. 1 ~ 0.03mm, the surface roughness ra is 2.5 ~ 0.63μ m, and the perpendicularity of each main plane to the assembly datum plane is 0. 1/300.
2. The dimensional accuracy, geometric accuracy and surface roughness of the hole.
The dimensional accuracy, shape accuracy and surface roughness of the bearing support hole on the box are required to be high, otherwise the matching accuracy between the bearing and the box hole will be affected, the rotation accuracy of the shaft will be reduced, and the transmission parts (such as gears) will easily produce vibration and noise. Generally, the dimensional accuracy of the spindle bearing hole of the machine tool spindle box is it6, the tolerance of roundness and cylindricity is not more than half of the aperture tolerance, and the surface roughness value is Ra 0.63 ~ 0.32 micron ... The dimensional accuracy of other support holes is it7~it6, and the surface roughness value is Ra 2.5 ~ 0.63 micron. ..
3. The mutual position accuracy of the main hole and the plane
Holes on the same axis should have certain requirements of coaxiality, and there should also be certain requirements of hole spacing dimension accuracy and parallelism between supporting holes. Otherwise, it will not only be difficult to assemble, but also worsen the operation of the shaft, increase the temperature, aggravate the wear of bearings, reduce the meshing accuracy of gears, cause vibration and noise, and affect the service life of gears. The tolerance of hole spacing between supporting holes is 0. 12 ~ 0.05 mm, the tolerance of parallelism should be less than the tolerance of hole spacing, and the general total length is 0.1~ 0.04 mm. Generally, the coaxiality tolerance of holes on the same axis is 0.04 ~ 0.0 1 mm, the parallelism tolerance between bearing holes and main planes is 0. 1 ~ 0.05 mm, and the verticality tolerance between main planes and between main planes and bearing holes is 0.1~ 0.04 mm.
Question 9: What are the main processing surfaces of box parts? The main processing surfaces of box parts are as follows
(1) dimensional accuracy, shape accuracy and surface roughness of box bearing hole
(2) The mutual position of each bearing hole in the box.
(3) the accuracy of the main plane of the box