China Shenzhen Perfect Precision Product Co., Ltd. company news

Configuration criteria of deep drawing parts a. The shape of drawing parts shall be as simple and symmetrical as possible. b. The size proportion of each part of the drawing part shall be appropriate, and the design of wide flange and deep drawing parts shall be avoided as far as possible. (D convex ＞ 3d, h ≥ 2d) Because such parts need more drawing times. c. The fillet radius of the drawing part shall be appropriate, and the fillet radius shall be as large as possible to facilitate the forming and reduce the number of drawing times. (1) Fillet radius of drawing parts. Rapid screening sheet metal sample library (2) The appropriate position for punching deep drawing parts or bending parts. (3) To prevent distortion and deformation during drawing, the width of A and B should be equal (symmetrical), that is, A=B. (4) Precautions for dimensioning on the design drawings of tensile parts The material thickness after stretching changes due to the different stress magnitude of the stretching parts. Generally speaking, the original thickness is maintained at the bottom center, the material at the bottom fillet becomes thinner, the material at the top near the flange becomes thicker, and the material at the fillet around the rectangular stretching piece becomes thicker. (5) Standard method for product dimensions of tensile parts When designing tensile products, the dimensions on the product drawing shall clearly indicate that the external dimensions or internal dimensions must be guaranteed, and the internal and external dimensions cannot be marked at the same time. (6) Marking method for dimensional tolerance of stretching parts The internal radius of the concave convex arc of the stretch piece and the height tolerance of the cylindrical stretch piece formed at one time are symmetrical deviations on both sides. The deviation value is half of the absolute value of the national standard (GB) Grade 16 accuracy tolerance, and is marked with ±.

1. Minimum bending radius of plate When the material is bent, the outer layer is stretched and the inner layer is compressed in the fillet area. When the thickness of the material is constant, the smaller the inner radius r is, the more serious the tensile and compression of the material will be; When the tensile stress of the outer fillet exceeds the ultimate strength of the material, cracks and breaks will occur. Therefore, the structural design of bending parts should avoid too small bending fillet radius. Specify the minimum bending radius for this purpose. L The bending radius refers to the inner radius of the bending piece, and t is the wall thickness of the material. L t is the material wall thickness, M is the annealed state, Y is the hard state, and Y2 is the 1/2 hard state. For the closed bending parts as shown in the figure below, the maximum bending height h shall not exceed 40mm. If it is required to exceed 40mm, it must be checked before use. 2. Minimum straight edge height for bending The straight edge height of bending should not be too small, otherwise it is not easy to form enough bending moment, and it is difficult to obtain the parts with accurate shape. The value h ≥ R+2t is acceptable. ① Minimum straight edge height requirements in general The straight edge height of bending parts shall not be too small, and the minimum height shall be h ＞ 2t according to the drawing requirements. Minimum straight edge height of bent parts ② Height of straight edge with special requirements If the straight edge height h ≤ 2t of the bending part is required in the design, the bending height shall be increased first, and then the bending shall be processed to the required size; Or bend after machining shallow grooves in the bending deformation area. Requirements for straight edge height in special cases ③ Height of straight edge with bevel on the side of curved edge When the bending part with bevel angle is on the side of the bending edge, the minimum height of the side is: h=(2 ～ 4) t ＞ 3mm Height of straight edge with bevel on the side of curved edge 3. Deformation treatment of bent straight edges ① When a ＜ R, after bending, there is still a residual arc near a on surface b. In order to avoid the residual arc, a ≥ R must be made. ② On U-shaped bending pieces, the two bending edges should be equal in length to avoid displacement to one side during bending. If not allowed, a process positioning hole can be set. ③ Prevent cracks or deformities when the side (trapezoid) is bent. The reserved groove shall be designed, or the root shall be changed to a stepped shape. Groove width K ≥ 2t, groove depth L ≥ t+R+K/2. ④ The reserved notch shall be designed to prevent the fillet from wrinkling after extrusion due to compression during bending. Such as the cut form at the fillet of the side plate (upper end, lower end) of the outdoor unit. B is equal to the cover plate thickness (t) ⑤ To prevent wrinkles on both sides of the right angle after bending, the reserved cut shall be designed. ⑥ Cut form to prevent springback after bending. A ≥ 1.5t (t - material thickness) ⑦ . Cut form to prevent cracks caused by bending after punching. ⑧ Prevent one side from contracting inward when bending. The process locating hole can be designed, or both sides can be bent at the same time, or the shrinkage problem can be solved by increasing the width. ⑨ The lapping form is bent into a right angle. 4. Bending of convex part If the bending curve is consistent with the step line as shown in figure a, sometimes it will crack and deform at the root. Therefore, make the bending curve keep away from the step line as shown in Fig. b, or design the notch as shown in c and d. 5. Hole edge distance on the bending piece Hole edge distance: punch the hole first and then bend it. The position of the hole should be outside the bending deformation area to avoid deformation of the hole when bending. The distance from the hole wall to the bending edge is shown in the table. Table Hole edge distance on bending piece ① When bending, the hole on the bending surface will be deformed after being stressed, and the value A of the hole edge distance (to the bottom root) is ≥ 4. ② When punching the bending edge, the distance L from the hole edge to the center of the bending radius R shall not be too small to avoid the hole deformation after bending and forming. Its value L ≥ 2t. 6. Process cut with local bending ① The bending line of the bending part shall avoid the location of sudden change in size When bending the edge of a section locally, in order to prevent bending cracks caused by stress concentration at sharp corners, the bending curve can be moved a certain distance to leave the sudden change of size (Figure a), or the process groove (Figure b) can be opened, or the process hole (Figure c) can be punched. Note the dimension requirements in the drawing: S ≥ R; Groove width k ≥ t; Groove depth L ≥ t+R+k/2. ② When the hole is located in the bending deformation zone, the cut form adopted Example of the cut form used when the hole is in the bend deformation zone 7. Design requirements for dead edge The length of the dead edge is related to the thickness of the material. As shown in the figure below, generally the minimum length of dead edge L ≥ 3.5t+R. Where, t is the material wall thickness, and R is the minimum internal bending radius of the previous process. 8. Process locating hole added during design In order to ensure the accurate positioning of the blank in the mold and prevent the offset of the blank during bending from generating waste products, the process positioning holes should be added in advance during the design, as shown in the following figure. Especially for the parts formed by multiple bending, the process hole must be used as the positioning benchmark to reduce the cumulative error and ensure the product quality. 9. When marking the relevant dimensions of bending parts, consider the manufacturability 10. Springback of bending parts There are many factors affecting springback, including mechanical properties, wall thickness, bending radius and positive pressure when bending. (1) The greater the ratio of the inner radius of the bending part to the plate thickness, the greater the springback. ⑵ Examples of methods for restraining rebound in design. At present, the springback of bending parts is mainly avoided by the manufacturer when designing the mold. At the same time, some structures are improved in design to reduce the springback angle, as shown in the figure below: pressing stiffeners in the bending area can not only improve the rigidity of the workpiece, but also help to restrain springback.

When designing product parts, the problem of easy manufacturing must be considered. Try to think of some methods that can not only make processing easy, but also save materials, and increase strength without waste. For this reason, designers should pay attention to the following manufacturing issues. The manufacturability of sheet metal parts refers to the difficulty of parts in punching, bending and stretching. Good process shall ensure less material consumption, fewer processes, simple mold structure, long service life and stable product quality. In general, the performance of materials, geometric shape, size and accuracy requirements of parts have the greatest impact on the processability of sheet metal parts. How to fully consider the requirements and characteristics of processing technology in the structural design of thin plate components, several design criteria are recommended here. 1. Simple shape criteria The simpler the geometric shape of the cutting surface, the more convenient and simple the cutting and blanking, the shorter the cutting path, and the smaller the cutting amount. For example, straight lines are simpler than curves, circles are simpler than ellipses and other higher order curves, and regular graphs are simpler than irregular graphs. The structure in Figure 2a is meaningful only when the batch is large, otherwise, it will be troublesome to cut during blanking. Therefore, the structure shown in Figure b should be used for small batch production. 2. Material saving criteria (configuration criteria for blanking parts) Saving raw materials means reducing manufacturing costs. The scraps of leftover materials are often treated as waste materials, so in the design of thin plate components, the leftover materials should be reduced as much as possible. The blanking waste shall be minimized to reduce material waste. Especially, the effect is remarkable when cutting off components in large batches. The ways to reduce cutting off are as follows: 3. Criterion of sufficient strength and stiffness ⑴ The bending edge with beveled edge shall avoid the deformation area (2) If the distance between two holes is too small, cracks may occur during cutting. For punching design of parts, proper hole edge distance and hole spacing shall be reserved to avoid punching cracks. The minimum distance between the punching edge of the part and the shape of the hole has certain restrictions depending on the shape of the part and the hole. When the punching edge is not parallel to the contour edge of the part, the minimum distance shall not be less than the material thickness t; In parallel, it shall not be less than 1.5t. The minimum hole edge distance and hole spacing are shown in the table. The round hole is the most solid and easy to manufacture and maintain, but the opening rate is low. The square hole has the highest opening rate, but because it is a 90 degree angle, the corners are easy to wear and collapse, resulting in mold repair and line stop The hexagonal opening has a 120 degree angle greater than 90 degrees, which is stronger than the square opening, but the opening rate at the edge is a little lower than the square opening. (3) The thin and long lath has low rigidity and is easy to crack during cutting, especially the tool is seriously worn. In general, the depth and width of the convex or concave part of the blanking part should not be less than 1.5t (t is the material thickness). At the same time, narrow and long cuts and too narrow grooves should be avoided to increase the strength of the cutting edge at the corresponding parts of the mold. 4. Reliable blanking criterion The semicircle tangent structure shown in Fig. 9a is difficult to cut. Because this requires accurate determination of the relative position between the tool and the workpiece. Accurate measurement and positioning is not only time-consuming, but more importantly, the accuracy of the tool usually cannot meet such high requirements due to wear and installation errors. Once there is a slight deviation in the processing of such structures, it is difficult to ensure the quality, and the cutting appearance is poor. Therefore, the structure shown in Figure b shall be adopted, which can ensure reliable blanking processing quality. 5. Criteria for avoiding sticking (configuration criteria for piercing parts) When punching and cutting in the middle of the component, there will be a problem that the cutter and the component are bonded tightly. Solutions: (1) Reserve a certain slope; (2) Connection of cutting surface When the lapping is made into 90 ° bending edge by punching in one process, the material should not be too hard, otherwise it is easy to crack at the right angle bend. The process cut shall be designed at the bending position to prevent cracking at the corner. 6. Bending edge vertical cutting surface criterion After cutting, the sheet metal shall be further formed, such as bending. The bending edge shall be perpendicular to the cutting surface, otherwise the risk of cracks at the intersection will increase. If the vertical requirements cannot be met due to other restrictions, a fillet shall be designed at the intersection of the cutting surface and the curved edge, with the radius greater than twice the plate thickness. 7. Gentle bending criterion Steep bends require special tools and are expensive. In addition, too small bending radius is easy to produce cracks and wrinkles on the inner side 8. Guidelines for avoiding small round curling Edges of thin plate members are often crimped, which has several advantages. (1) Stiffness is strengthened; (2) Sharp edges are avoided; (3) Beautiful. However, two points should be paid attention to when crimping. One is that the radius should be greater than 1.5 times the plate thickness; The other is not completely round, which is difficult to process. The curling shown in Fig. 18b is easier to process than that shown in respective a. 9. Non bending criterion of groove edge A certain distance shall be kept between the bending edge and the slot edge. The recommended value is the bending radius plus 2 times of the wall thickness. The stress state of bending zone is complex and the strength is low. Slots with notch effect should also be excluded from this area. Not only can the entire slot be far away from the curved edge, but also can the slot span the entire curved edge (see Figure 19). 10. Manufacturing criteria for complex structure combination It is difficult to form components with too complex spatial structures by bending. Therefore, the structure should be designed as simple as possible. When it is not complicated, composite members can be used, that is, multiple simple thin plate members can be combined by welding, bolting, etc. The structure of Figure 20b is easier to machine than that of Figure 20a. 11. Criteria for avoiding straight line penetration Thin plate structure has the disadvantage of poor lateral bending stiffness. Large plate structures are prone to buckling and instability. Further bending and fracture will occur. Generally, the groove is used to improve its rigidity. The arrangement of pressure grooves has a great influence on the effect of improving the stiffness. The basic principle of pressure groove arrangement is to avoid straight line penetration in the non pressure groove area. The through narrow band with low stiffness is easy to become the inertial axis of buckling instability of the whole plate surface. Instability always revolves around an inertial axis. Therefore, the arrangement of pressure grooves should cut off this inertial axis and make it as short as possible. In the structure shown in Figure 21a, the non pressure groove area forms a plurality of through narrow strips. Around these axes, the bending stiffness of the entire plate is not improved. The structure shown in Figure 21b has no potential connected unstable inertial axis. Figure 22 lists the common groove shapes and arrangements. The effect of stiffness enhancement increases gradually from left to right. Irregular arrangement is an effective way to avoid straight line penetration. 12. Connected Arrangement Criteria of Pressure Groove The weak link is the low end fatigue strength of the groove. If the groove is connected, some of its end points will be eliminated. Figure 23 shows the battery box on a truck, which is subject to dynamic load. The structure in Figure 23a has fatigue damage at the groove end. The structure in Figure 23b does not have this problem. Steep groove end face shall be avoided, and the groove shall extend to the boundary if possible (see Figure 24). The penetration of the pressing groove eliminates the weak end. However, there should be enough space at the intersection of the grooves to reduce the interaction between the grooves 13. Space notching criterion The instability of spatial structures is not limited to one aspect. Therefore, setting pressure grooves on only one plane cannot improve the stability resistance of the whole structure. For example, the U-shaped and Z-shaped structures shown in Figure 26 will lose stability near the edges. The solution to this problem is to design the pressure groove as a space 14. Local relaxation criterion Wrinkling occurs when local deformation on the sheet is seriously obstructed. The solution is to set a few small pressure grooves near the folds, so as to reduce the local stiffness and deformation resistance. 15. Configuration criteria of blanking parts ⑴ Minimum punching diameter or minimum side length of square hole When punching, it shall be limited by the strength of the punch, and the size of the punch shall not be too small, otherwise the punch may be easily damaged. The minimum punching diameter and minimum side length are shown in the table. *T is the material thickness, and the minimum punching size is generally not less than 0.3mm. (2) Principle of punching notch Sharp corners shall be avoided for punching notches, as shown in Fig. a. Sharp corners are easy to shorten the service life of the mold, and cracks are easy to occur at the sharp corners.

Sheet metal (Metal Plate;; SheetMetal), a processing technology, has not been completely defined so far. According to a definition in a foreign professional journal, it can be defined as: sheet metal is a comprehensive cold working process for sheet metal (usually less than 6mm), including shearing, punching/cutting/compounding, folding, riveting, splicing, forming (such as automobile body), etc. Its remarkable feature is that the thickness of the same part is consistent. Sheet metal has the characteristics of light weight, high strength, conductivity (can be used for electromagnetic shielding), low cost, and good mass production performance. It has been widely used in electronic appliances, communications, automotive industry, medical equipment and other fields. For example, in computer chassis, mobile phones, MP3, sheet metal is an essential component. With the application of sheet metal becoming more and more extensive, the design of sheet metal parts has become a very important part of the product development process. Mechanical engineers must master the design skills of sheet metal parts, so that the designed sheet metal can not only meet the requirements of product function and appearance, but also make the manufacturing of stamping dies simple and low cost. Based on the above reasons, it is very necessary to systemically sort out the data on the structural design of sheet metal parts, and I believe that it will have some effect on the users of the rapid addition screen. Structural design knowledge I of sheet metal parts: The so-called thin plate refers to a steel plate whose thickness is much smaller than its length and width. Its lateral bending resistance is poor, so it is not suitable for the occasion under lateral bending load. Thin plate is metal in terms of its material, but because of its special geometric shape and small thickness, the processing technology of thin plate components has its particularity. There are three types of processing technologies related to thin plate components: (1) Blanking: it includes shearing and blanking. (2) Forming: it includes bending, folding, curling and deep drawing. (3) Connection: it includes welding, bonding, etc. The structural design of thin plate components shall mainly consider the requirements and   characteristics of processing technology. In addition, pay attention to the batch size of components. Thin plate members are widely used because thin plates have the following advantages: (1) . It is easy to deform. In this way, various forms of components can be manufactured by simple processing technology. (2) The thin plate component is light in weight. (3) The processing amount is small. Because of the high surface quality of the sheet and the small dimensional tolerance in the thickness direction, the sheet does not need to be processed. (4) It is easy to cut and weld, and can manufacture large and complex components. (5) The shape is standardized for automatic processing.

Many years of experience in etching technology for mechanical products, summed up the importance of mold etching in the process of mold making, mold etching technology has two methods. (1) using immersion etching ;   (2) the etching solution is injected into the mold-shaped cavity for etching. No matter what kind of etching method is used, the formulation of the etching solution is the key to maintain a fast etching speed, but also requires a smooth etched surface and small damage to the anti-etching ink. For plastic mold graphics etching commonly used formula is to use nitric acid, phosphoric acid, sulfuric acid to prepare the three acid etching solution, this formula etching speed is moderate, the etched surface smoothness is good, etching solution is stable and can be stored for a long time, while this etching agent for most resist ink have better safety. Chemical degreasing cleaning method is more effective on the mold surface cleaning, while cleaning costs are lower than organic solvents, high safety, but the investment in equipment is larger, for slightly larger molds in the cleaning process also need to have a traveling car. The process of chemical degreasing: mold by receiving - pre-cleaning protective oil - hanging - chemical degreasing - hot water washing - secondary flow water washing - acid washing - Tertiary flowing water washing - self inspection of oil removal effect - passivation - tertiary flowing water washing - hot water washing - drying - under hanging - turn anti-corrosion layer production.

Machining sales methods, hardware industry sales methods, CNC industry sales methods and techniques. 1, for sales representatives, sales knowledge is undoubtedly must master, no learning as the foundation of sales, can only be regarded as speculation, can not really experience the wonders of sales.   2. A successful sales pitch is not a story that happens by chance, it is the result of study, planning and the application of a sales representative's knowledge and skills.   3. Selling is entirely the application of common sense, but only when these concepts, proven in practice, are applied to the active person can they produce results.   4、Before achieving a stunning result, it must first do a good job of tedious preparation.   5. The preparation and planning work before the sales pitch must not be neglected and should not be taken lightly, come prepared to win. Prepare sales tools, opening statements, questions to ask, words to say, and possible answers.   6. The combined power of thorough preparation and inspiration on the spot often easily dismantles strong opponents and leads to success.   7. The best sales representatives are those with the best attitudes and knowledge of products and the most attentive service.   8. the company's product-related information, manuals, advertising, etc., must be studied, memorized, while collecting competitors' advertising, promotional materials, manuals, etc., to study, analyze, in order to know themselves and each other, so that they can really know each other. Take corresponding countermeasures.   9, sales representatives must read more about the economy, sales books, magazines, especially must read the newspaper every day, to understand the country, social news, news events, visit customers only on the day, which is often the topic, and not to be ignorant, shallow insight.   10. The road to obtaining orders begins with the search for customers, cultivating customers is more important than the immediate sales volume, if you stop replenishing new customers, sales representatives will no longer have a source of success.   11. A transaction that is not beneficial to the customer is also bound to be harmful to the sales representative, which is one of the most important rules of business ethics.   12. When visiting customers, sales representatives should always believe in the rule that even if they fall down, they should grab a handful of sand. Meaning, the sales representative can not return empty-handed, even if the sale did not close, but also to enable the customer to introduce you to a new customer.   13. Select the customer. Measure the customer's willingness and ability to buy, do not waste time on the indecisive.   14. The important rule of strong impressions is to help people feel important.   15. Be on time for your appointment - being late means: I don't respect your time. There is no excuse for being late. If you can't avoid being late, you must call over and apologize before the appointment time, and then continue the unfinished sales pitch.   16. Sell to Mr. Power who can make a buying decision. If the person you are selling to does not have the power to say buy, you are unlikely to sell anything.   17. Each sales representative should realize that only the eyes on your customer. Sales can be successful.   18. Have a plan and natural approach to the customer. And make the customer feel beneficial, and can smoothly negotiate, is a sales representative must work hard to prepare for the work and strategy beforehand.   19．The sales representative can not reach a deal with every customer he visits, he should try to visit more customers to increase the percentage of transactions.   20. Know your customers, because they determine your performance. 21. Before you become a good sales representative, you have to become a good investigator. You have to find, to track, to investigate, until you feel everything about your customers, so that they become your good and bright friends.   22. Believe in your product is a necessary condition for sales representatives: this confidence will be passed on to your customers, if you do not have confidence in their own goods, your customers to discuss it naturally will not have confidence. The customer is not so much because you speak with a high level of logic and be said eyes, but rather that he is convinced by your deep confidence.   23. Good performing sales representatives withstand failure, partly because they have uncompromising confidence in themselves and the products they sell.   24. Know your customers and meet their needs. Without understanding the needs of customers, it is like walking in the dark, wasting effort and not seeing results.   25. For sales representatives, there is nothing more valuable than time. Knowing and selecting customers is what allows sales representatives to put time and effort into the most likely customers, rather than wasting it on people who can't buy your product.   26. There are three rules for increasing sales: - is to focus on your important customers, two is to be more focused, and three is to be more more focused.   27. Customers are not high or low, but there is a hierarchy. According to the customer level to determine the number of visits, time, you can make the sales representative's time to play the effectiveness.   28. Approach customers must not be uniformly formulaic, must be fully prepared in advance, for each type of customer, to take the most suitable approach and opening.   29. Sales opportunities are often - fleeting, must be quick, accurate judgment, careful attention, so as not to miss a good opportunity, and should strive to create opportunities.   30. Focus your energy on the right target, the right use of time and the right customer, you will have the eye of the tiger in sales.   31. The golden rule of sales is how you like people to you, how you treat others; the platinum rule of sales is to treat people in the way they like to be treated.   32. Let customers talk about themselves. Let a person talk about themselves, you can give you a great opportunity to explore common ground, establish a good feeling and increase the chances of completing the sales pitch.   33. Sales must have patience, visit constantly, so as not to be too hasty, and not to take it lightly, must be calm, look at the face, and at the right time to facilitate the transaction.   34 customers refuse to sell, do not be discouraged, to further efforts to convince customers, and try to find out the reasons for customer refusal, and then the right medicine.   35. To the customer around the curious inquiries, even if it is never possible to buy, but also enthusiastic, patient to explain to them, introduce. It must be understood that they are very likely to influence the customer's decision directly or indirectly.   36. Sell to help customers, not to sell for commission.   37. In this world, what do sales representatives rely on to tug at the heartstrings of customers? Some people think fast, logical and eloquent arguments to make people: some people with a voice, generous and both exciting speech to move people's hearts. However, these are all matters of form. In any time, in any place, to convince anyone, there is only one factor that always works: sincerity.   38. Do not sell, but help. Selling is to give something to the customer, but helping is to do something for the customer.   39. Customers think logically, but what makes them act is emotion. Therefore, the sales representative must push the customer's heart button. 40．The relationship between the sales representative and the customer never needs the formula and theory of calculus, but the news of the day, the weather, and other topics. Therefore, do not try to use simple reasoning to make the customer move.   41. To impress the customer's heart rather than head, because the heart is closest to the customer's wallet pocket.   42. When you can't answer a customer's objection, you must never be perfunctory, deceitful or deliberately tongue-lashing. You must answer as much as possible, and if you can't get it, you must ask the leadership as soon as possible to give the customer the most Shaanxi, satisfactory and correct answer.   43. listen to the purchase signal - if you are very attentive in listening to words, when the customer has decided to buy, usually give you a hint. Listening is more important than talking.   44. The rules of the game of selling are: a series of activities aimed at closing the deal. Although the deal is not equal to everything, but no deal is not everything.   45．The rule of closing is: ask the customer to buy. However, 71% of sales representatives did not close the deal with the customer is the reason, did not ask the customer to close.   46. If you do not ask the customer to close, it is as if you have aimed at the target but did not pull the trigger.   47. At the juncture of your deal you have firm confidence, you are the embodiment of success, as the old adage goes: success comes from success.   48. If the sales representative can not get the customer to sign the order, product knowledge, sales skills are meaningless. No deal, no sale, it's as simple as that.   49．Not getting the order is not a shameful thing, but not knowing why you didn't get the order is a shame.   50. Closing proposal is the right solution to the right customer at the right time.   51. When closing, to convince the customer to take action now. Delay in closing may lose the opportunity to close. -A sales maxim is: today's orders are in front of you, tomorrow's orders are far away.   52. To overcome obstacles to closing with confidence. Sales is often the performance and the ability to create confidence to buy. If the customer does not buy confidence B, even if the cheaper will not help, and low prices will often scare customers away.   53. If you fail to close the deal, the sales representative should immediately make an appointment with the customer to meet the next date - if you and the customer face to face, can not make an appointment to meet the next - time, it will be much harder to meet with the customer. Every call you make must result in at least some form of sale.   54. Sales representatives must not because the customer did not buy your products and rude to him, then you lose not only a sales opportunity - but the loss of a customer.   55．Track, track, track again - if it takes 5 to 10 contacts with the customer to complete a sales pitch, then you do whatever it takes to make it to that 10th time.   56. Get along well with others (colleagues and customers). Sales promotion is not a one-man show, to work together with colleagues and become partners with customers.   57. Effort will bring luck - take a close look at those who are very lucky, that good luck is that they have worked hard for years to get, you can also be as good as them.   58. Don't blame others for anti failure - taking responsibility is the pillar point for getting things done, hard work is the standard for getting things done, and getting things done is your reward (money is not a reward - money is just an accessory crystal for successful completion of tasks).   59. Stay the course - can you see no as a challenge, not a rejection? Are you willing to stay the course through the 5 to 10 visits required to complete your pitch? If you can do it, then you'll begin to appreciate the power of persistence.   60. Use numbers to find your formula for success - determine how many leads, how many calls, how many prospects, how many meetings, how many product presentations, and how many follow-ups you need to complete a pitch, and then follow that formula. 61. Face the job with enthusiasm - make every pitch feel like: this is the best one ever.   62. Leave a deep impression on the customer corpse - this impression includes a kind of bin, j new image, a professional image. When you walk away, how do customers describe you? You are always leaving an impression on others, sometimes dark, sometimes sharp; sometimes good, sometimes go mouth may not. You can choose the impression you want to leave on another U people, but also must be responsible for the impression you leave.   63. The law of sales failure is: to compete with customers for high and low.   64. The clear response to competitors' attacks is poise, merchandise, enthusiastic service and professionalism. The most foolish way to deal with the competition's offensive is to say bad things about each other.   65. Sales representatives are sometimes like actors, but since they are involved in sales, they must be dedicated, confident, and sure that their work is the most valuable and meaningful

Machined parts machining process heat treatment, generally can be divided into two kinds of preparatory heat treatment and final heat treatment. Preliminary heat treatment: its purpose is to improve the mechanical properties, eliminate internal stress, in order to prepare for the final heat treatment, generally including annealing, normalizing, tempering and aging treatment and other such processes. The preparatory heat treatment is usually carried out after rough machining. Final heat treatment: its purpose is to improve the hardness and wear resistance of the parts, including quenching, carburizing, nitriding and other processes, generally after the semi-finishing process, before the finishing process. Content two: the precision of machining The accuracy of machining is mainly reflected in the following aspects: dimensional accuracy, geometric shape accuracy and mutual position accuracy, where geometric shape accuracy includes roundness, straightness and flatness, etc., and mutual position accuracy includes parallelism, perpendicularity and coaxiality, etc.

For precision parts, the processing is very strict, the processing process has a tool in, tool out, etc.. For the size of specific requirements, precision requirements, such as 1mm plus or minus how many microns, etc., if the size of the wrong too much will become scrap, then the equivalent of having to re-process, time-consuming and laborious, and sometimes even make the entire processing material scrap, which causes an increase in costs, at the same time, the parts are certainly not available. For precision parts processing is mainly dimensional requirements, such as how much the cylindrical diameter, there are strict requirements, positive and negative errors within the specified requirements to be qualified parts, otherwise they are unqualified parts; length, width and height also have specific strict requirements, positive and negative errors are also specified, such as an embedded cylinder (take the most simple basic parts for example), if the diameter is too large, more than the error tolerance range, it will Caused by, insert not into the situation, if the actual diameter is too small, more than the lower limit of the negative value of the error allowed, it will cause inserted too loose, not solid problems occur. These are unqualified products, or the cylindrical length is too long or too short, beyond the error tolerance range, are unqualified products, are to be scrapped, or re-processed, which will inevitably cause an increase in costs. Precision parts processing requirements is in fact the main size problem, must be strictly in accordance with another plus drawings for processing, processing out of the actual size will certainly not be the same as the theoretical size of the drawings, only, as long as the processing size within the error tolerance is qualified parts, so the requirements of precision parts processing is in strict accordance with the theoretical size for processing. Second is the advanced precision parts processing equipment and testing equipment, advanced processing equipment makes processing precision parts easier, higher precision, better results. Testing equipment can detect the parts that do not meet the requirements, so that all the products sent to customers really meet the requirements.

In the field of mechanical parts processing industry, generally will use mechanical parts processing drawings, the drawings will indicate the mechanical parts processing procedures, processes and requirements, today we take a look at what mechanical parts processing technology requirements! First, the contour treatment of the parts.   1, unannotated shape tolerance should be in line with the requirements of GB1184-80.   2, not note the length of the size of the allowable deviation ± 0.5 mm.   3, not noted rounded corner radius R5.   4, not noted chamfer are C2.   5、Sharp corner chamfering blunt.   6、Sharp edge chamfering blunt, remove burr flying edge. Second, the parts surface treatment   1, the parts processing surface, there should be no scratches, scrapes and other defects that damage the surface of the parts.   2、No defects such as black skin, bump, messy buckle and burr are allowed on the processed thread surface. Before painting, all steel parts must be free of rust, oxide, grease, dust, mud, salt and dirt.   3、Before removing rust, remove grease and dirt from the surface of steel parts with organic solvent, alkali, emulsifier, steam, etc.   4、The time interval between the surface to be coated by shot blasting or manual rust removal and the primer coating shall not be more than 6h.   5, riveted parts in contact with each other's surface, before connecting must be coated with a thickness of 30 ~ 40μm anti-rust paint. The edge of the lap joint should be closed with paint, putty or adhesive. Due to processing or welding damage to the primer, to repaint. Third, the parts heat treatment   1, by tempering treatment, HRC50 ~ 55.   2, medium carbon steel: 45 or 40Cr parts for high-frequency quenching, 350 ~ 370 ℃ tempering, HRC40 ~ 45.   3, carburizing depth of 0.3mm.   4、High-temperature aging treatment.

Now the mechanical parts processing industry is developing very rapidly, the general mechanical parts processing methods are more than one, so we know what types of mechanical processing is divided into? Today let me share with you!   1. There are many forms of mechanical parts forming. (1) hot processing: casting, forging, welding, etc. (2) cold processing: turning, planing, milling, punching, pressing, riveting, etc.   2. There are also many forms of cold working. (1) Sheet metal parts: punching, pressing, riveting, etc. (2) Comprehensive parts: turning, planing, milling, etc. 3. General machining mostly refers to the processing of integrated parts. The forms are as follows (1) workpiece rotary processing: turning (2)Tool rotary processing: drilling, milling, boring, surface grinding (3) Workpiece and tool rotary machining: internal grinding, external grinding, rolling cutting (4) Workpiece and tool are not rotary type processing: planing, inserting, pulling (5) Other: electric machining, laser, waterjet, etc.   4. By processing content to distinguish the form of processing. (1) rotary body parts processing: turning, internal and external grinding, etc. (2) surface processing: milling, pulling, plane grinding, etc. (3) the processing of holes: drilling, boring, expansion, reaming, pulling, grinding, etc. (4) slot processing: turning, milling, inserting, pulling, etc.