The basic components of a plastic mold are: mold frame (the entire core of the support part), cavity (plastic material flow channel), mold core (determines the structure of the product molding), pressure plate (fixed core), positioning guide pillar, water cooling system components.
2. What are the common materials used for mold frame?
Commonly used materials for mold frames are: S55, S45, S50, and Japanese Fudeba.
3. What is the meaning of insert? What is the common material of inserts? What is the role?
The inserts are a series of splices that make up the mold core. The common materials of inserts are SAD61 and AK80 of Daido, Japan. The role of inserts is mainly to form a complex mold core, which can form a complex product when injecting glue.
4, mold generally need to go through what heat treatment process? What is the role of heat treatment?
The mold generally need to go through quenching, tempering, nitriding and other heat treatment processes.
The role of heat treatment is to increase the hardness of the mold, strength, remove internal stress to increase the life of the mold.
5, what is called etching? What are the types of etching? What is the difference?
Etching is the surface of the mold with chemical or electrical processing methods to produce a different pattern of the bottom of the texture, in order to increase the surface effect of the plastic parts, to improve the yield of the product. Etching according to different processing methods, divided into chemical etching and EDM etching, according to the different etching effect is divided into fine grain and coarse grain. Chemical etching is generally low processing efficiency, easy to form uniform fine lines, EDM etching processing efficiency, easy to form different coarse lines, but poor uniformity.
6, what is called mold release agent? What are the commonly used mold release agents? What is the role?
Release agent is an oil coated on the surface of the mold, which can make the workpiece easy to pull out of the mold after injection.
Commonly used mold release agents are dry, neutral, oil, the higher the oil, the greater the impact on the surface effect of the workpiece.
7, mold precision by which factors?
The precision of the mold is determined by the machining precision, assembly precision, positioning precision and other factors.
8, select the mold parting surface to consider what factors?
The main consideration for selecting the parting surface of the mold is the convenience of pulling out the mold and extracting the core.
9, what is the tilt of the mold pulling? What is the range of mold pulling tilt?
The taper of mold pulling means that in order to pull out the mold core from the molded plastic parts conveniently without hurting the plastic parts, the mold core usually has a taper, and this taper is called the taper of mold pulling. The range of mold pulling tilt is generally 0.5°-1°.
10, what is the line position? What is the core? What are the factors that limit the length of the core?
The row position is a set of sliders that extract the core from the side. The core of the core is called the core. The length of the core is determined by the stroke of the row position, and at the same time with the length of the oblique guide pillar, the longer the core the larger the volume of the mold, while the core strength and stiffness of the worse.
11, ejector pin according to the shape of which types? According to the location of what kinds of categories? What is its role?
The ejector pin is divided into round ejector pin and flat ejector pin according to the shape;
The ejector pin is divided into flat ejector pin and slanting ejector pin according to the position;
The ejector pin mainly ejects the molded plastic parts, and sometimes the ejector pin is also used for marking the mold cavity number.
12, what are the similarities and differences between the plastic mold and hardware stamping mold?
Plastic mold: generally for the hot mold (processing for the thermal process), so we have to consider the thermal balance and thermal deformation, and therefore the general mold frame is larger, and there is a water-cooling system. At the same time, due to the existence of difficult to control the thermal deformation, so the processing accuracy will not be very high, the efficiency is not as high as the hardware stamping mold. On the other hand, the processing process is different, the plastic mold using the material for the molten fluid, through the injection to fill the cavity of the mold, the speed is slower.
Hardware stamping die: generally cold mold (processing process for the normal temperature process), no water cooling system, for the precision requirements of particularly high processing, rely on immersion oil heat dissipation, while easy to achieve high processing accuracy. On the other hand hardware stamping die according to the different processing purposes, divided into the drop die and molding die, processing of materials for a certain degree of rigidity, high efficiency.
13, what is called copper work, copper work in the mold processing in what role?
As the name implies: it means that the workpiece is processed with copper material, also called profiling mold in mold terminology. Its shape is flat on one side and the core shape on the other. Because it is made of copper, the dimensional accuracy is very precise. It can be used to perform precision operations during mold processing. Control the precision of mold core.
1, what kinds of engineering plastic materials are commonly used? What are the characteristics of each?
Engineering plastics is a suitable for structural materials and mechanical and electrical parts of high-performance plastics, mainly used in a variety of engineering technologies. Long-term heat resistance is above 100℃.
Commonly used types of engineering plastics are ABS, nylon, PC, POM and so on.
ABS: Slightly yellow, opaque, non-toxic, odorless, is a tough, rigid material. tensile strength of ABS is not high, high impact strength. Good friction resistance, low coefficient of friction, moderate heat resistance and low temperature resistance, good electrical properties.
Nylon: excellent mechanical properties. High tensile strength, good toughness, can withstand repeated impact vibration; use temperature range of -40 ℃ ~ 100 ℃, good wear resistance, low coefficient of friction, excellent self-lubricating; good electrical insulation properties, arc resistance; easy to color and non-toxic; oil resistance, resistance to hydrocarbons, esters, and other organic solvents, resistance to weak alkali, but not acid and oxidizing agents, do not resist polar solvents, such as water, alcohols; easy to process and molding; high water absorption, dimensional High water absorption, poor dimensional stability.
The advantages of injection molding are: good fluidity, resistance to friction, easy color matching. Disadvantages are: soft, easy to shrink, easy to form Phi Feng.
PC: almost colorless or slightly yellowish; high light transmission; low water absorption, good dimensional stability; molding shrinkage is small and uniform; excellent impact strength, and high tensile, bending, compression strength; has a high modulus of elasticity; but low fatigue strength, easy to produce stress cracking; good heat resistance, long-term use of up to 130 ℃, and at the same time, good cold resistance. Cold resistance, embrittlement temperature of -100 ℃; has excellent dielectric properties; molding before the requirement of baking material at 120 ℃ for 24 hours, the general injection molding using high material temperature (300 ℃), high molding pressure and rapid prototyping methods.
POM: is a tough and elastic material, even at low temperatures still have very good creep characteristics, geometric stability and impact resistance.POM both homopolymer materials and **** polymer materials. Homopolymer materials have good ductile strength, fatigue strength, but not easy to process; *** polymer materials have good thermal stability, chemical stability and easy to process.POM is a crystalline material and not easy to absorb water. The biggest drawback: due to the high degree of crystallization leads to a fairly high shrinkage rate, can be as high as 2% ~ 3%. It has a very low coefficient of friction and high temperature resistance.
2, what is meant by glass fiber? How to express in the engineering documents? What is the role of glass fiber?
Glass fiber is the abbreviation of glass fiber, generally refers to the glassy fibers or filaments made of silicate solutes.
The need to use materials containing glass fiber, in the engineering documents (drawings) generally expressed as a percentage. Such as PA66 +25%
Materials containing glass fibers can enhance the mechanical properties of raw materials, thermal properties, dimensional stability has improved significantly, tensile strength, bending strength and compression strength, good abrasion resistance, heat distortion temperature increase, but at the same time increase the brittleness and reduce surface quality.
The glass fiber content is usually between 15% -45%, the content in more than 45% processing difficulties, commonly used in 30%. Generally choose alkali-free glass fiber, the diameter of 6 microns.
3, commonly used flame retardant is what? Its role and what is the principle? Will it evaporate over time?
Flame retardant: a substance that can prevent combustion, reduce the rate of combustion or (and) increase the ignition point. Usually a polymer bromide .
Decomposes at high temperatures, but does not evaporate over time at room temperature or below 130 degrees Celsius.
Currently used flame retardants are decabromodiphenyl ether, tetrabromodiphenyl ether and so on.
Function: can prevent combustion, reduce the burning speed or (and) increase the ignition point.
Principle: general flame retardant contains carbonizer, heat absorber, flame quencher, synergist and other components. Carbonating agent for the phosphorus-containing compounds, in combustion can promote organic compounds carbonization, the formation of carbon black film; heat-absorbing agent for the metal hydrate, through the evaporation of its own water molecules, take away the heat required for combustion; flame quenching agent for the bromine or chlorine-containing halogenated products, through the isolation of the oxygen can be affected by the combustion; synergistic agent for the antimony compounds, to enhance the role of flame quenching agent.
The use of chemical agents on the conditions required for combustion play a role in blocking, isolation, suppression, etc. to affect the combustion performance.
4, what is called color powder? What is called color masterbatch? What is its role? Color powder in which stage to join the plastic material?
A kind of mechanical method must be used to disperse in the object evenly; can change the visible color of the object or make the colorless object coloring of the dispersed particles of the material is called color powder. Toner is highly susceptible to oxidation and will change color at high temperatures or radiation.
According to the coloring concentration of the final product made of resin and coloring agent of a homogeneous mixture, and then through the extrusion pelletizing unit or two-roll pelletizing unit, so that the mixture of melting and mixing, the production of the required shape and size of the colored plastic particles called masterbatch.
After adding color powder or color masterbatch to plastic products, it can play the role of beautifying the appearance of the products, improving the commodity value of the products; anti-aging; shielding effect on ultraviolet rays; conductive effect; filler, enhancement and so on.
Generally added before the mechanical mixing and stirring, the use of mechanical methods to make the color powder can be evenly dispersed in the plastic.
5, what is called the water mouth material? What are the requirements for the use of the sprues? In which stage of adding the water mouth material into the plastic material?
The sprues are the part of material left on the sprue in order to form the product in the process of injection molding, the smaller the proportion of sprues to the product, the lower the cost of the product, and at the same time the smaller the sprues tend to lead to lower productivity.
The sprues can generally be filled into the molding material of the product, the filling ratio is generally within 10%, the maximum should not be higher than 30%. The presence of sprues in the injection molding industry is unavoidable, in order to reduce the cost of the product, the sprues in the original rubber material is also very common. The sprues are usually added to the hopper of the equipment after mixing with the original rubber.
6, try to compare the strength, specific gravity, price, processing methods and other aspects of plastic materials and aluminum metal.
Material
Strength
Specific gravity
Price
Surface treatment
Processing method
Plastic
Lower
2.7
33/Kg
No
Pouring, stretching, punching
Aluminum metal
Higher
1.0~1.4
16/Kg
Needed
Pouring, drawing, punching
There is a trend in the industry to use plastic instead of aluminum due to the lower price of the plastic material, which is easy to form complex shapes and also doesn't need surface treatment.
7, introduce the main applications and considerations of engineering plastics.
Engineering plastics are used in machinery, transportation, instruments, meters, electrical, electronic, communications, chemical and medical equipment and daily necessities.
In the processing of light, thin, short, small parts and components, there are ordinary processing of poor fluidity, product residual internal stress and molding shrinkage and flammability and other defects. The mechanical properties of plastic materials are generally lower than metal materials, easier to fatigue.
8, the plastic material of the extraction of grain refers to what process? What is the drying temperature of plastic material? How to realize the exhaust?
Pulleting of plastic material is a kind of extrusion molding granulation process.
The drying temperature of plastic material varies depending on the type of material. For materials with low water absorption, such as PS, can be processed without baking, for common materials such as ABS, nylon, PMMA, etc., the drying temperature is generally controlled between 75 ℃ - 90 ℃, baking time is generally 1-1.5 hours; for hard materials such as PC, its drying temperature is generally 110 ℃ - 130 ℃, baking time is generally more than a few hours.
Exhausting is realized by using the exhaust groove, and setting the exhaust groove on the mold can effectively carry out the exhaust treatment. When the exhaust is not good, the high temperature gas is easy to burn the workpiece or form gas lines on the surface of the workpiece.
9, what is the chemical name of ABS? What are its main physical properties?
By acrylonitrile (A), butadiene (B), styrene (S) composed of ternary **** polymer and its modified resins, ABS resin as the base material of the plastic is called ABS plastics, referred to as ABS.
ABS: slightly yellow, opaque, non-toxic, odorless, is tough and hard rigid material,
ABS tensile strength is not high, impact strength Higher, good friction resistance, low coefficient of friction, moderate heat resistance and low temperature resistance, good electrical properties, little affected by changes in temperature, humidity, frequency, ABS is resistant to water, inorganic acids, alkalis, salts and most hydrocarbons and alcohols.
10, introduce the main production base of plastic materials.
China, China - Taiwan, Japan, the United States, Germany, Britain, France, Italy, Belgium and so on.
The engineering materials used within the mainland are more Taiwan Starlight, Chimei and Formosa Plastics materials, but also Japan - Changchun materials.
1, injection molding machine into which categories?
There are four types of injection molding machines according to the mold form: vertical injection molding machine, horizontal injection molding machine, angle injection molding machine, multi-mold injection molding machine.
There are two types of injection molding machines according to the plasticizing method: plunger-type injection molding machine, screw-type injection molding machine (screw-type injection molding machine has a higher tonnage).
2, injection molding machine nominal process parameters? What does it mean?
Nominal process parameters
Grams of injection
Ounces of injection
Clamping force
Line
Screw extruding force
Representation of the significance
Maximum grams of the part that can be produced
Ounces = 28.3 grams
Maximum ounces of the part that can be produced< /p>
Generally expressed in tons, determined by the hydraulic cylinder
Indicates the maximum size that can come out of the mold
Determines the injection pressure
3, what is the injection pressure? What is the holding time? What is clamping force?
The pressure added to the cross-section of the barrel cavity during injection molding is called injection pressure.
The time from the filling of the cavity to the end of the holding pressure is called the holding pressure time.
Injection process to keep the mold closed and the force added to the mold is called clamping force. Clamping force is generally used as a nominal parameter for injection molding machines.
4, plastic material processing temperature range? How much does temperature affect processing?
The specific processing temperature of plastic material varies depending on the raw material. Generally speaking, it is between 180℃-330℃.
During injection processing, temperature control is critical. When the processing temperature of the material is not reached, the material is not completely dissolved, and the injection process can not be completed; when the processing temperature is high, the material has been decomposed in the barrel, and the quality of the injection molded plastic parts defects, affecting the efficiency of the injection molding process.
5. What is the role of cooling circulating water? How much does it affect the processing efficiency?
Frozen water from the freezing water machine to the mold, hot water from the mold to the freezing water machine, after a continuous cycle to reduce the temperature of the mold in the process of injection molding, to maintain the balance of the mold temperature does not rise, does not fall.
In the production of the mold connected to the cooling water, you can maintain the temperature balance of the mold in the operation, maintenance of the mold life; maintain the stability of the process. Reduce the energy consumption and time of repeated heating and cooling, and improve the processing efficiency of the product.
6, plastic material heating is completed with what? How to control the heating temperature?
The heating of the plastic material is done by using the heating ring on the barrel of the injection molding machine to heat the barrel. The temperature is not the same in different areas of the barrel.
The temperature of the heating coil heating barrel is controlled by the temperature control system of the injection molding machine, the plastic material should be heated according to the different raw materials required by the different temperature range to adjust the temperature control system of the injection molding machine.
7, injection molding machine processing efficiency by which to decide? How to improve the processing efficiency?
The processing efficiency of the injection molding machine is determined by the injection cycle of the product, including injection time, holding pressure and cooling time, mold opening time, picking time, mold closing time and so on. Shortening the mold opening time, picking time, mold closing time can effectively improve the processing efficiency.
8, the robot can realize what action? What is the main control element?
Manipulator is a kind of automated production equipment that can imitate the function of human upper limbs to carry out production operation, injection molding robot can replace the human to realize the action of adding, taking out and arranging the products, replacing the molds and removing the wastes, etc.
The main control element of the robot is the mold opening time.
Its main control elements are: cylinders, hydraulic control (pneumatic control) valves, travel limit switches, non-contact travel limit switches, potentiometers, rotary transformers, induction synchronizers, encoders.
9, a brief introduction to several injection molding machine, and compare its advantages and disadvantages.
Vertical injection molding machine: injection device and the axis of the mold device is a vertical line, covers an area of small, easy to disassemble the mold, easy to place inserts, products often need to be taken out of the top of the hand or other methods, it is not easy to realize the full automation of the operation, the body is high, the machine's stability is poor, refilling and maintenance is not convenient.
Horizontal injection molding machine: a line of horizontal arrangement, the body is low, conducive to operation and maintenance, good stability, occupies a small space height, but covers an area of large, easy to realize the full-automatic operation.
Angular injection molding machine: arranged vertically with each other, especially suitable for molding products in the center of the product does not allow traces of the gate.
10, what are the common processing equipment for mold? Please compare the similarities and differences between wire cutting and slow walking wire.
The mold of the common processing equipment are lathes, milling machines, planers, grinders, insertion machines, drilling equipment, CNC machining centers, machining
center, electrical processing equipment, precision machining equipment, special molding equipment, profiling equipment, etc..
The use of tool electrodes and parts (positive and negative) between the impulse spark discharge phenomenon of galvanic corrosion to corrode excess metal, so as to achieve a variety of metal parts processing phenomenon called EDM wire cutting.
The processing characteristics of wire cutting:
a: the use of EDM wire cutting processing, due to the use of only a very thin wire as a tool electrode, reducing the workload required due to the manufacture of tool electrodes, and save valuable non-ferrous metals;
b: you can cut any shape of the complexity of the holes, narrow grooves, and small fillet radius sharp corners and with a variety of shoulders of non-circular cores, inserts;
c: can cut any shape of complex holes, narrow grooves and small rounded radius sharp angles and with all kinds of shoulders. Round cores, inserts;
c: you can get a higher roughness level of the surface;
d: a high degree of machine automation, generally by imitating the shape of the processing, photoelectric tracking and programming can be automated;
e: generally only a gauge can be molded in a single run, no need to switch to electric gauge;
f: machined parts do not need to go through the pre-processing;
g: the machine can cut the hole of any shape complexity, narrow grooves and small round radius sharp corners and non-circular with a variety of shoulder
g: the program prepared by the mold, photoelectric tracking map can be reused, and can be used to compensate for the gap to process different requirements of the workpiece;
h: can be processed carbide and hardened parts.
11, what is the concept of one out of four? What is the significance to the numbering of points?
Four products of the same structure can be injected in the same mold, which is called one out of four.
When the same mold can produce more than one product with the same structure, generally different markings are made on the cavities of each product. For example: marked 1, 2, 3, 4 or A, B, C, D, etc., in order to facilitate in the subsequent production process can be found in time to find the root cause of the anomaly, saving time to solve the problem.
12, according to which factors to choose the tonnage of processing equipment?
The tonnage of the injection molding machine should be selected according to the clamping force and injection capacity of the injection molding machine.
The clamping force is determined by the maximum mold closure force that can be generated by the clamping mechanism; the injection capacity is expressed in terms of the maximum theoretical injection volume, and usually the injection molding machine has ultra-small, small, medium, large, and ultra-large.
1, what is oil injection? What is the difference between oil injection and colored plastic?
The process of spraying oil on the base surface of an object using a specific tool with a well adjusted oil is called oil spraying. Oil spraying can only change the appearance of the surface of the object condition, the matrix pigment does not have the slightest effect, after removing the oil layer, the matrix and the oil layer between the obvious level of difference; colored plastic is the matrix pigment from inside to outside the same, as a whole.
2, what is silkscreen? What are the commonly used screen printing methods?
Through the use of squeegees on the screen extrusion, so that the ink through the mesh in the substrate on the composition of the graphic process called screen printing.
Commonly used methods of screen printing include manual screen printing, pad printing, hot stamping, etc.
3, what is called curing agent? Curing agent to improve screen printing and oil spraying adhesion effect?
The relevant solvent that can play a curing role is called curing agent. In the screen printing and oil spraying process with a curing agent, can be better solid screen printing pattern, or better make the oil layer adhering to the substrate. It can improve the friction coefficient of the screen-printed pattern and the oil layer. Ensure product quality.
4, what is called hand plate? How is the hand plate processed?
Hand plate is generally referred to in the design and development stage, in order to more clearly understand the design of the will to use the corresponding parts or other processing methods to form a product model. Now there are special hand plate processing equipment, or with the car, milling, planing and other machining methods processing molding.
5, what is called color plate? Color plate in the inspection of the significance of how?
Check the color of the material used in the benchmark reference, called the color plate. It can be a sample, in kind, can also be a piece of size specifications containing a four-sided plate.
6, ultrasonic welding is the basic principle?
Ultrasonic welding is also thermal welding, the heat is the use of ultrasonic excitation of plastic for high-frequency mechanical vibration to generate energy to obtain, when the ultrasonic waves are directed to the surface of the plastic to be welded, the plastic mass will be ultrasonic excitation and rapid vibration, thus generating mechanical work, and then converted into heat, the surface temperature of the plastic welded and melted, and non-welded temperature does not rise ultrasonic through the head of the plastic introduced by welding, when the welding head stops, the plastic is welded. When the welding head stops, the plastic immediately cools and solidifies, completing the plastic welding.
1, what is called shrinkage? What are the common causes of shrinkage? What is the difference between shrinkage and lack of glue?
Plastic products in the mold due to the occurrence of shrinkage caused by local surface sagging defects, called shrinkage.
Shrinkage usually occurs in the product structure of the thick glue bit or thick and thin glue bit conversion, generally arising from the following reasons: a, the injection volume is insufficient; b, the injection pressure, speed, time is low and short; c, the material temperature is too low or too high; d, the mold temperature is too high or too low e, the product structure is not reasonable f, the mold structure is not reasonable g, the holding pressure, time is not enough h, the back pressure is small;
Plastic products do not completely fill the mold cavity phenomenon called glue shortage.
Lack of glue usually occurs in the thin glue bit, long column bit, the process of the farthest position. The general causes are: a, the amount of material is not enough (blocking the hopper mouth, plasticizing capacity under the amount of pre-molding is not enough) b, equipment instability caused by abnormal changes in the process c, the injection pressure is too low, time is too short, speed is too slow d, the mold cavity, the sprue, the resistance to loss of large e, low material temperature, low mold temperature f, poor fluidity of the material and so on.
2, what is called fusion marks? What is the difference between fusion mark and gas pattern?
Melting marks: a kind of linear marks of the molded parts, which is caused by injection or extrusion when two streams of material meet, and can not be completely fused at the interface;
Air lines: Due to the strength of the material itself can not withstand the inherent or extrinsic stress, the surface of the plastic products or the interior of the fine lines such as the frost spots appear.
The presence of fusion marks on the surface of the plastic part is a normal and unavoidable defect in the processing process,
The presence of air cracks on the surface of the plastic part is an avoidable defect that can be prevented by adjusting the processing technology, material and mold structure
and so on.
3. How the peaks are formed? How to reduce the peaks?
Phihong: molding process overflow into the mold surface gap, and left on the molded part of the residual material.
The clamping force of the injection machinery is not enough, the injection speed is too fast, the temperature of the dissolved material is too high, the mold temperature is too high, the holding pressure is too high, the strength of the mold material is low, and the sealing of the parting surface is not enough, etc. All of these will lead to the production of Phi Phi;
According to the technical parameters of the machinery, we can increase the clamping force; reduce the injection speed, and use multi-stage injection to go from fast to slow; reduce the temperature of the dissolved material; and reduce the temperature of the mold by accessing the circulating coolant. Temperature; for mold reasons can be used to improve the mold polishing, grinding, barrel grinding, ball bead impact and other methods to reduce the appearance of Phi Feng.
4, the formation of color difference with what factors?
The formation of color difference is related to the quality of colorant, colorant preparation method, raw material quality, molding conditions.
5, how is the formation of material brittleness? How to add the water mouth material?
It is mainly due to the accelerated aging of the material when the temperature changes too fast during the formation of the parts, or the proportion of the sprues is seriously exceeded, or the amount of glass fiber added is exceeded. Water mouth material can generally be filled into the product molding material, filling ratio is generally within 10%, the maximum should not be higher than 30%.
6, how to prevent deformation when processing plastic products?
The deformation of plastic parts should be deformed from the cause of deformation to find a solution:
A, reduce the melt temperature and mold temperature can be overcome due to molecular orientation imbalance caused by deformation.
B, in the design of plastic body structure, each part of the section thickness should be as consistent as possible, can prevent the solid cooling is not appropriate, that is, due to the plastic
the parts of the cooling contraction caused by inconsistent deformation.
C, for the specific conditions of the plastic parts, respectively, to adjust the corresponding process parameters can prevent the deformation caused by improper process operation.
7, how is the formation of the stray point? How to minimize the spots?
Molding materials do not meet the requirements of use is the main reason for the production of miscellaneous points. Molding materials in the packaging, transportation, preheating and pre-drying process mixed with impurities or different grades of raw materials; raw material particle size is not uniform or too large, will make the molded plastics contain miscellaneous points.
Methods to reduce the spot: A, the raw material should be sifted out of foreign impurities, the selection of uniform particle size of the raw material;
B, to maintain environmental cleanliness and hygiene, in the pretreatment and molding process, to prevent dust and other foreign matter from the hopper and molds are mixed into the dissolved material, so as not to produce a spot.
8. What is the reason for decolorization? How to prevent decolorization?
Decolorization is not added to the curing agent and stabilizer in the screen printing ink, or not according to the process of drying, resulting in screen printing ink adhesion is not enough. In order to prevent decolorization, the curing agent and stabilizer should be added to the screen printing ink and dried according to the process requirements.
9, what is called aging? Plastic aging and those factors?
Aging refers to the passage of time, the material in the occurrence of a variety of irreversible chemical and physical changes in the process of the phenomenon.
The aging of plastic is related to light, temperature, humidity, time, rainfall and other climatic conditions.
1, flame retardant is what instrument test? How to classify the flame retardant grade?
The flame retardancy of plastics is tested by plastic combustion tester. (Currently there are models for PF-1 China State Shipbuilding Industry Corporation 725 Research Institute of manufacturing, HVR-2 horizontal - vertical combustion tester, Guangzhou Electrical Apparatus Research Institute)
Materials of the flame retardant level is based on the material after ignition of the combustion time and combustion behavior of the division. It is divided into: FV-0 , FV-I, FV-II, FV-III, for details, refer to the standard of GB/T2408-1997 to operate and categorize.
2, colorimeter (chromatograph) can measure what characteristics of plastic parts?
The colorimeter (chromatograph) can measure the color of the plastic parts of the pigment bias, and between the pigments and the absolute value of the synthesis.
3, drop test test plastic parts of what performance?
The drop test examines the strength of plastic parts.
The drop test examines the strength performance of plastic parts.