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What are the schemes for metal surface treatment

Engaged in lathe, machine processing industry for ten years, have a good understanding of metal surface treatment, today with you to learn about electroplating knowledge.

In industrial design, we often use electroplating technology. First, let’s understand what electroplating is.

Electroplating is the process of plating a thin layer of other metals or alloys on some metal surfaces by electrolysis principle. It is a process of using electrolysis to attach a metal film to the surface of metals or other materials so as to prevent metal oxidation (such as rust), improve wear resistance, conductivity and reflectivity. Corrosion resistance (copper sulfate, etc.) and aesthetic enhancement.

Electroplating is divided into copper plating, gold plating, silver plating, chromium plating, nickel plating and zinc plating and other specific processes, especially in the field of industrial design, zinc plating, nickel plating and chromium plating are the most widely used. And there must be some difference between them, right?

01- zinc plating

A kind of

Definition: Zinc plating refers to the surface treatment technology of plating a layer of zinc on the surface of metals, alloys or other materials to make them beautiful and rust-proof.

Features: Low cost, general anti-corrosion, silver-white color.

Application: 3C product requirements, etc.

Nickel plating on 02-

A kind of

Definition: Nickel plating is a method of electrolytic or chemical plating of nickel on metals or some non-metals.

Features: Beautiful, can do decoration, high price, slightly complex process, the color is silver and yellow.

Applications: Electronic products, copper parts, etc.

03- chrome plating

A kind of

Definition: Chromium is a slightly blue silver-white metal, electrolytically or chemically coated with a layer of chromium on metals or certain non-metals, known as chromium plating.

Features: There are two kinds of chromium plating, the first is to play a decorative role, bright appearance, good wear resistance, rust resistance is not as good as galvanizing, better than oxidation; the second is to increase the hardness and wear resistance of metal parts, which is the function of parts.

Application: Bright decorative parts and decorative joints on household appliances, electronics and other products.

Expand knowledge:

1-Electroplating production is mainly polluted by heavy metals in sewage and sewage. The state has strictly controlled the expansion of the electroplating industry and reduced it year by year.

2-The Main electroplating processes in China are zinc, copper, nickel and chromium plating, of which zinc plating accounts for 50%, copper, chromium and nickel plating accounts for 30%.

3-Galvanizing or cadmium plating can be used if the purpose is to prevent rust; nickel or chromium plating is the best choice if the focus is to prevent wear and tear.

How to plan hardware stamping production and design standards

In the process of metal stamping production, we often have metal stamping parts crushed or scratched, or when customers come to the workshop to check, they find that the workshop is not clean, which may lead to loss of customers or increase production costs. In order to avoid the discovery of these phenomena, we should pay attention to Hardware stamping parts production planning and formulation of design standards.

Planning of metal stamping production:

1. Strict inspection system should be established in production. The first piece of metal stamping parts produced every day must be thoroughly inspected and put into production only after passing the inspection. At the same time, patrol inspection should be strengthened. If accidents occur, timely handling should be carried out.

2. To ensure the cleanliness of the die cavity in the stamping process, the orderly processed workpieces in the workplace should be placed neatly.

3. Adhere to the civilized production system, such as metal stamping parts and spare parts transmission must use appropriate workstation equipment, otherwise the surface of the workpiece will be crushed and scratched, which will affect the surface quality of the workpiece.

Hardware stamping design standard:

1. In the design of metal stamping parts, it is necessary to ensure that the dimension accuracy and surface roughness are as low as possible in the normal use. It is also necessary to facilitate the interchange between metal stamping parts, reduce waste products and ensure the stability of the quality of metal stamping parts.

2. When designing metal stamping parts, we should use the existing equipment, process equipment and flow to process metal stamping parts as far as possible. At the same time, it should be conducive to prolong the service life of stamping die.

3. The design of stamping parts must be conducive to improving the utilization rate of metal materials, reducing the variety and specifications of materials, and reducing the consumption of materials as much as possible. The low-cost materials should be adopted when permitted so as to make the parts free of waste and less waste arbitration.

How to develop CNC Machining plan and improve efficiency

In metal processing, from the design drawings of parts to the qualified delivery of finished products of parts, considering a series of factors such as the arrangement of processing technology route of parts, the selection of processing machine tools, the selection of cutting tools, positioning and clamping in parts processing, it is necessary to advance the design drawings and technical requirements of parts before starting programming. Detailed analysis of NC processing technology and reasonable system of process route can avoid possible product quality problems due to improper consideration of process plan. The following is a brief introduction of the NC machine tool formulation process to improve efficiency in Baida Borun Petrochemical Company.

First, the principle of coarse and fine first.

(1) In order to improve the production efficiency and ensure the quality of the finished parts, roughing process should be arranged first in the cutting process, and a large amount of processing allowance before finishing should be removed in a relatively short time, at the same time, the requirement of homogeneity of finishing allowance should be satisfied as far as possible.

(2) after finishing the rough machining process, the semi finishing and finish machining should be arranged after changing the knife. The purpose of arranging semi-finishing is to arrange semi-finishing as a transitional process when the uniformity of the remaining allowance after roughing can not meet the requirements of finishing, so as to make the finishing allowance small and uniform.

(3) When arranging the finishing process with one or more knives, the final contour of the part should be processed continuously with the last knife. At this time, the position of the cutting tool should be properly considered, and the cutter and the cutter should not be cut out or changed or stopped in the continuous contour as far as possible, so as to avoid the elastic deformation caused by the sudden change of cutting force, resulting in surface scratches, abrupt shape changes or retained cutter marks on the smooth connecting contour.

Two, the principle of first coming and then far away.

The distance between here and near is based on the distance between the processing part and the cutter point.

(1) In general, especially in rough machining, it is usually arranged to process the parts near the tool setting point first, and then the parts far from the tool setting point, so as to shorten the tool moving distance and reduce the empty travel time.

(2) For CNC turning, it is advantageous to maintain the rigidity of the blank or semi-finished parts and improve the cutting conditions.

Three, the principle of internal and external first.

For the parts that need to process both inner surface (inner shape and cavity) and outer surface, it is usually arranged to process the inner shape and inner cavity first and then the outer surface when making the processing plan. This is because it is difficult to control the size and shape of the inner surface, the rigidity of the tool is relatively poor, the durability of the tool tip (edge) is easily affected by cutting heat, and it is difficult to remove chips in processing.

Four. The shortest way to take a knife line.

The key point of determining the tool path is mainly used to determine the tool path of rough machining and empty travel, because the tool path of finishing cutting process is basically carried out along the contour sequence of its parts.

(1) Tool path generally refers to the path through which the tool moves from the point of tool setting (or the fixed origin of the machine tool) until it returns to that point and ends the processing procedure, including the path of cutting and the non-cutting free travel such as tool introduction and cutting.

(2) On the premise of guaranteeing the processing quality, making the processing program have the shortest tool path can not only save the execution time of the whole processing process, but also reduce some unnecessary tool consumption and wear of sliding parts of machine tool feeding mechanism.

Tips for deep hole machining of CNC machine tools

What is deep hole?

Deep hole refers to the hole whose hole depth and aperture ratio are L/d (> 5). Deep hole processing is a difficult problem in mechanical processing, especially in deep hole processing with large depth-diameter ratio. The difficulty lies in the slenderness, poor rigidity and low strength of the tool, which can easily cause tool deflection, heat dissipation difficulty, chip removal difficulty, and often lead to larger diameter, taper or hole deflection. Elephants fail to meet the quality requirements.

The nozzle diameter of aero engine is 6mm, the hole depth is 105mm, and the depth diameter ratio is 17:1. Extra large depth-diameter ratio increases the processing difficulty of this part. In order to produce qualified holes, it is necessary to formulate a reasonable processing plan, select appropriate processing equipment and tools. After the trial cutting of the specimen, the author chooses the appropriate processing parameters, and finally determines the reasonable processing method.

I. Introduction of parts

A nozzle part, whose total length is 105mm, inner hole of rod is 6+0.12mm, wall thickness is 2mm, surface roughness is Ra3.2um, depth-diameter ratio is 17:1, belongs to deep hole processing parts, whose material is GH4169 which is difficult to process.
Compared with general steel cutting, the tool life of this kind of Superalloy hole processing is lower by more than 50%, and the processing efficiency is low and the cost is high. The main difficulties in machining high temperature alloy are:

(1) the cutting force is large and the power consumption of the machine tool is high.

(2) Hole processing is semi-closed cutting, which produces high cutting heat and chips that are difficult to discharge in time, away from the tool tip, and the tool wear is more severe;

3. It is difficult to ensure the accuracy of high temperature alloy hole by means of conventional drilling.

(4) In superalloy hole processing, tool wear is much faster than that of common steel, and tool materials with better cutting performance are needed.

In order to solve the above processing difficulties, when processing this deep hole, it is necessary to select appropriate processing equipment and tools to ensure the processing accuracy of parts.

Two, processing technology design and analysis

It is necessary to lengthen twist drill and chip breaking to select conventional drilling methods for deep hole processing of parts. It is not only of low processing accuracy, poor surface roughness, low processing efficiency, high labor intensity of operators and difficult to guarantee quality, but also of great difficulty in blocking or breaking drill bits. Therefore, it is better to select cutting tools. Select special tool for deep hole machining.

The selection of equipment takes into account the company’s product types, large differences in deep hole processing product structure, and small batches of production, it is impossible to purchase special machine tools for deep hole processing. In order to better ensure the accuracy requirements of deep hole, combined with the factories, the appropriate processing equipment is selected to meet the technical requirements of deep hole processing.

1. tool selection

There are many kinds of deep hole processing tools, such as gun drill, spray suction drill, sleeve drill, carbide indexable deep hole drill, internal chip removal deep hole drill and sub-dry deep hole processing system.

Jet suction drill is suitable for refitted lathes and horizontal processing centers, and easy to process workpiece materials. The drilling diameters of sleeve drill and deep hole drill with internal chip removal are not suitable for drilling small holes of 6mm. The minimum drilling diameter of carbide indexable deep hole drill is 20mm.

The sub-dry deep hole processing system mainly uses compressed air for chip removal and cooling, and uses atomized cutting fluid for lubrication, requiring special processing equipment.

The gun drill is suitable for processing deep holes of 2-_20mm, L/D > 100, Ra6.3-Ra0.4um surface roughness and accuracy of H7-H10.

After comparing the above deep hole cutting tools and the actual situation of our factory, we decided to use gun drill to process this deep hole.

The gun drill consists of three parts: hard alloy drill point, drill pipe and handle.

Oil holes are drilled on the drill tips to enhance the cooling and lubrication of the drill bit and smooth discharge of chips, and cemented carbide with good toughness and vibration resistance is selected as the matrix. TiC or TiN can be coated on the surface to improve the hardness and wear resistance of the drill bit. 40Cr seamless steel pipe is generally used for drill pipes.

The principle is that high-pressure oil is injected into the middle hole at the back of the drill pipe and the chips are forced to be discharged with the cutting fluid from the space between the V-groove and the workpiece hole wall after reaching the cutting area through the waist hole.

The front angle of such deep hole drilling is usually 0 degrees in order to manufacture. It has no transverse edge, and the drill tip deviates from the axis. When drilling, the front of the drill tip forms a small cone, which can break the chips into two segments at the drill tip and make it easier to discharge.

2. equipment

Gun drill is used to drill holes in the center of revolving workpiece. When processing, the workpiece usually rotates and the drill bit feeds in a straight line. It is more suitable for turning centers, lathes equipped with high pressure cooling system and vertical machine tools, cutting tools or workpiece rotating occasions.

Considering the application situation of gun drill processing and the existing equipment of the company, the author chooses Turning-Milling compound processing center in this part processing. This equipment can realize the rotation of parts, and also equipped with high-pressure internal cooling system to meet the application situation of gun drill. Drilling can be done.

3. gun drill guide hole processing

The gun drill is a non-equilibrium drill bit, and unbalanced groove shape means unbalanced cutting force.

In order to reduce the radial cutting force around the bit, the guide sleeve or guide hole must be shared.

Typical gun drill machine tools are equipped with gun drill guide sleeve, and the turning and milling machining center selected in this case is not a special machine tool for gun drill, and it is not equipped with guide sleeve, and there is no fixture, so it is impossible to design guide sleeve.

Therefore, the author considers using drilling to guide the hole to balance the cutting force of the gun drill. Through a large number of experimental data, it is concluded that:

The depth of the guide hole of gun drill should be 1-2 times the diameter of gun drill, and the diameter should be 0.004-0.012mm larger than the diameter of gun drill bit

Which countries have high risks in foreign trade

For foreign traders, this year has been a year of great crisis. The United States provoked a trade war and frustrated Sino-US trade. Under the influence of the strong US dollar, once emerging markets suffered a sharp fall in their currencies and had to adopt import restrictions to stabilize the exchange rate.

The following is a summary of countries or regions where trade risks have risen sharply. Please strengthen the awareness of wind control and strictly adhere to the bottom line of payment when doing business with customers in these countries.

1. United States

At present, some foreign trade friends have feedback that when the list just landed, due to the carelessness of both buyers and sellers, the goods arrived at the port only to find that additional tariffs need to be paid, so the buyer abandoned the goods.

2. crash four countries

In addition to the initiative to close the door of the United States, there are still some countries can not sustain it.

There’s a new term for VITA, Venezuela, Italy, Turkey and Argentina.

Venezuela, don’t mention it. Banknotes are like waste paper.

According to a report released by Venezuela, daily inflation is now 4%, and monthly inflation has risen from 223% in August to 233%. The International Monetary Fund (IMF) said earlier this year that it expected Venezuela’s inflation rate to reach 10,000,000% this year.

Italy is actually a hidden bomb in Europe. Once it happens, it will be very important.

The Italian government has just raised its fiscal deficit to 2.4% of GDP in 2019, 0.8 percentage points higher than the previous commitment of 1.6%. The European Union has a headache.

Turkey suffered the collapse of the lira currency this year.

The lira has fallen by about 37% this year (though it has risen by 10% in the past two weeks), and the impact of the currency crisis has spread to the broader economy. In September, Turkey’s CPI rose 6.3% year-on-month, while transportation costs and food prices rose sharply, by 37% and 28%, respectively.

Many foreign businessmen have already reported that “after Turkey was sanctioned by the US economy, customers said they could not pay for it”, “the lira depreciated seriously, and the new customers finally could not pay for it”…

Argentina pesos is the worst currency in emerging markets this year.

Since falling into exchange rate fluctuations in late April, the inflation rate of the second largest economy in South America has reached 30%. In the first eight months of this year, the Argentine Peso has depreciated by 98%. On September 25, the governor of Argentina’s central bank, who has just been in office for three months, announced his resignation, and a large number of people took to the streets to protest against inflation. On the same day, the exchange rate of the US dollar against Argentina pesos was 40, a record high. At the beginning of 2017, the exchange rate of the US dollar against the Argentina Peso was around 17.

What is more serious is that this set of Domino dominoes may also take over many other emerging market countries. IFA believes that the vulnerability of emerging markets will spread to a wider extent and be highly concentrated in some countries, especially South Africa, Indonesia, Lebanon, Egypt and Colombia.

Pakistan

Good brother Pakistan has not been able to sustain the growing trade deficit. On October 16, the Pakistani Federal Tax Commission issued an announcement imposing import adjustment tariffs ranging from 5% to 90% on 570 luxury goods and non-essential imports, which are valid until June 30, 2019.

Development of metal parts

Due to the rapid development of hardware parts production technology and the impact of high labor costs, developed countries have accelerated the transfer of low and medium-grade products to the third world, producing only some high-value-added products.

In Europe and the United States, along with the design of building hardware products in developed countries, which are easy to install and maintain, doityourself products and tools are very popular in the market.

China’s hardware export earns only 3% of the total export. It is not only a matter of technological content, but also a matter of brand.

Brand includes a lot of contents, including service, reputation and so on. Credibility is gold, and honesty is the fundamental way to do business. If the hardware products we produce are sold under our own brand instead of sticking to other people’s brand, and can also be sold at the same price as sticking to the brand, then our GDP will not know how many times.

At the same time, the intervention of big conglomerates is a key factor for China’s hardware industry.

How to create a brand that matches the market of hardware fittings in China is a problem that we need to solve urgently.

With the entry of WTO, a large number of well-known international brands will also pour into China, which is what we often call wolf. There is nothing to fear when the wolf comes. The key is that we need to have a good hunting gun to block it.

The development of production and marketing in China’s hardware industry must conform to the trend of internationalization at home and abroad, and promote the development of enterprises with new marketing to create international concepts.

Hardware products of our country have hardly any internationally recognized brands. Except for the first domestic enterprise to obtain the slideway and hinge of the home hardware industry, “China’s well-known trademark” enterprise, there are still relatively few domestic well-known hardware enterprises.

I believe that after a period of hard work, China’s hardware products will become more and more internationally.

Introduction of mould

In industrial production, various kinds of moulds and tools are obtained by injection, blow moulding, extrusion, die casting or forging, smelting and stamping. In short, the mould is a tool used to make moulding objects. This tool is composed of various parts, and different moulds are composed of different parts. It mainly realizes the processing of the shape of the articles by changing the physical state of the formed material. Known as the “mother of industry”.

Under the action of external force, the billet becomes a tool with specific shape and size. It is widely used in stamping, die forging, cold heading, extrusion, powder metallurgy parts pressing, pressure casting, as well as engineering plastics, rubber, ceramics and other products of compression or injection molding. The die has a specific contour or inner cavity shape, and the blank can be separated according to the contour shape (blanking) by applying the contour shape with the edge. The shape of the inner cavity can be used to obtain the corresponding three-dimensional shape of the blank. The mold generally consists of two parts, the movable die and the fixed die (or punch and concave die), and the two parts can be divided into two parts. When separate parts are removed, the blank is injected into the mold cavity to form. Mould is a precise tool with complex shape and bearing the bulging force of billet. It requires high structural strength, stiffness, surface hardness, surface roughness and processing accuracy. The development level of die production is one of the important marks of the level of mechanical manufacturing.

Comprehensive Performance of Nonmetallic Compensator

Non-metallic compensators are widely used in many engineering fields because of their good comprehensive performance. Prudential compensators are commonly used in ventilation, dust removal and smoke exhaust, air conditioning and heat preservation pipelines and equipment with low working pressure.

In pipeline system, if there are simultaneously thermal stress caused by temperature change, local stress caused by vibration of equipment and fixed support, and stress caused by system installation deviation, rigid connection will inevitably lead to deformation or failure of pipeline system at the weakest point. If the flexible non-metal compensator is used, this kind of damage can be avoided. This is related to the unique motion form of non-metal compensators. These motion forms determine the multi-dimensional displacement performance of non-metallic compensators.

The pressure-bearing single-wave body and multi-wave body compensators play an irreplaceable role under some special working conditions. The electronic weighing scale used in the desulfurization and powder injection system of a steel plant used metal compensator to compensate the equipment and pipeline. Because of the large reverse thrust, the electronic weighing scale can not be adjusted accurately, and can not be returned to zero and weighed correctly. The rectangular caliber and large displacement compensator can only be made of non-metallic materials. Through special structure design and material design, the working condition requirements are met.

How to remove wax from aluminium and other metal surfaces

Wax removal, such as polishing wax, is often required in the treatment of aluminium and other metal surfaces. So what is the principle of wax removal? What are the ingredients of wax removal water and what effect do you need to achieve?

Metal surface dewaxing usually uses dewaxing water, such as ht425 super dewaxing water and so on. Wax removal water is mainly composed of surfactants, auxiliaries, corrosion inhibitors and cosolvents, which are scientifically blended by special technology. Wax removal water is a water-based multi-functional cleaning agent, mainly composed of surfactants, metal corrosion inhibitors and solvents. It has the emulsifying ability to wax fouling. As well as the cleaning power of oil contamination, it can not only remove wax thoroughly, but also clean oil, no corrosion to the workpiece, no color change, no oxidation and rust after cleaning.

Usually polishing wax is used to produce and process metal surface wax. The wax scale of polishing wax is mainly composed of paraffin, fatty acid, rosin soap, metal oxide and some inorganic solid polishing particles such as corundum, silicon carbide, high alumina ceramics, etc. Solid particles are distributed uniformly in the polishing wax system in powder form, as well as some grinding cloth reel debris, grinding metal matrix powder and its oxides. Wax scale and workpiece are mainly adhered by mechanical adhesion, intermolecular force adhesion and electrostatic force adhesion. It is difficult to remove wax scale particles when the mechanical adhesion is less than 011 micron. This is based on a long time observation of various wax scale. The key to the preparation of ht425 super dewaxing water and other reagents commonly used on the market is the rational mixing of various surfactants, additives and corrosion inhibitors. By reducing surface tension, wetting permeability and emulsifying, dissolving and solubilizing properties can be improved, so as to enhance the permeability and solubility. The compounding of nonionic surfactants and anionic surfactants has been widely used for a long time. Adding ionic surfactants can make the cloud point of nonionic surfactants have a wide range and form mixed micelles. It is easier to form micelles by weakening the interaction between the hydrophobic chains of the two surfactants, which decreases the CMC of the mixed liquids, the surface tension and the surface activity of the mixed liquids. Therefore, the wax removal water must be of high quality and have good comprehensive performance. Its wax removal ability, rust prevention, defoaming and stability are the four important technical indicators for evaluating the quality of wax removal water. After the rust-proof, defoaming and stability meet the application requirements, the wax removal ability is the decisive index to evaluate the quality of the wax removal water. The wax removal ability is determined by the type, quantity and composition of surfactants in the wax removal water formula.

Generally speaking, wax removal water is a kind of product which can efficiently clean the residual polishing wax of metal surface in the process of grinding and polishing. Its significance is also extraordinary. Its cleaning speed and thoroughness of wax removal will directly affect the production of follow-up products.