Custom Injection Molding: Things You May Want to Know

In the world of CNC precision machining, the possibilities extend far beyond just shaping and cutting materials. One of the most exciting aspects of modern machining is the ability to customize the surface color of your parts, enhancing both aesthetics and functionality. At F&Q-Tech, we offer a wide range of color customization options to meet your specific needs. In this article, we'll explore the different color surface treatment methods we use, their advantages and disadvantages, and which materials they are best suited for.

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1. Electroplating


Electroplating involves depositing a thin layer of metal onto the surface of a part using an electric current. Common plating metals include chromium, nickel, zinc, and gold.• Advantages:Enhanced Durability: Provides excellent corrosion and wear resistance.Aesthetic Appeal: Offers a shiny, reflective finish.Versatility: Can be applied to various metals, including steel, brass, and copper.• Disadvantages:Environmental Concerns: The process can involve hazardous chemicals.Cost: Can be more expensive due to the need for specialized equipment and materials.• Suitable Materials:Metals: Steel, brass, copper, and other conductive materials.Not Ideal For: Non-conductive materials like plastics and ceramics.



2. Anodizing



Anodizing is an electrochemical process that converts the metal surface into a decorative, durable, corrosion-resistant oxide layer, most commonly used on aluminum.• Advantages: Corrosion Resistance: Excellent for protecting aluminum parts.Color Stability: Colors are embedded in the oxide layer, making them resistant to fading.Hardness: Increases the surface hardness of the material.• Disadvantages:Corrosion Resistance: Excellent for protecting aluminum parts.Color Stability: Colors are embedded in the oxide layer, making them resistant to fading.Hardness: Increases the surface hardness of the material.• Disadvantages:Limited to Aluminum: Primarily used for aluminum and its alloys.Color Limitations: While versatile, the color range is not as extensive as some other methods.



3. Powder Coating



Powder coating is a dry finishing process where finely ground particles of pigment and resin are electrostatically charged and sprayed onto the part, then cured under heat.• Advantages:Durability: Highly resistant to scratches, chips, and fading.Environmentally Friendly: Produces less hazardous waste compared to liquid paints.Versatile Color Range: Offers a wide variety of colors and finishes.• Disadvantages:Thickness: Can be thicker than other coatings, which may not be suitable for precision parts.Curing Time: Requires heat curing, which can be time-consuming.• Suitable Materials:Metals: Steel, aluminum, and other metals.Plastics: Certain types of heat-resistant plastics.Not Ideal For: Materials that cannot withstand the curing temperature.



4. Chemical Coloring



Chemical coloring involves immersing the part in a chemical solution that reacts with the metal to produce a colored oxide layer.• Advantages:Uniform Color: Provides a consistent and even color distribution.Cost-Effective: Generally less expensive than other methods.Simple Process: Requires less equipment and setup.• Disadvantages:Limited Color Range: Typically limited to black, blue, and brown shades.Durability: Less resistant to wear and corrosion compared to other methods.• Suitable Materials:Stainless Steel: Commonly used for stainless steel parts.Copper Alloys: Suitable for brass and bronze.Not Ideal For: Aluminum and other reactive metals.



5. Laser Coloring



Laser coloring uses a laser to create microstructures on the surface of the material, which interact with light to produce colors without the use of pigments or dyes.• Advantages:Permanent Colors: Colors are embedded in the material and do not fade.Eco-Friendly: No chemicals or pigments are used.Precision: Allows for intricate designs and patterns.• Disadvantages:Cost: Can be more expensive due to the high cost of laser equipment.Limited to Certain Materials: Primarily used for metals and some plastics.• Suitable Materials:Metals: Stainless steel, titanium, and other reflective metals.Plastics: Certain types of transparent and reflective plastics.Not Ideal For: Materials that are not reflective or cannot withstand laser energy.



6. Hot-Dip Galvanizing



Hot-dip galvanizing involves immersing the part in a bath of molten zinc, creating a protective coating that is highly resistant to corrosion.• Advantages:Long-Lasting Protection: Provides excellent corrosion resistance.Cost-Effective: Generally less expensive than other corrosion protection methods.Durability: The coating is thick and robust.• Disadvantages:Aesthetic Limitations: The finish is not as smooth or visually appealing as other methods.Weight: Adds a significant amount of weight to the part.• Suitable Materials:Steel: Commonly used for steel structures and components.Not Ideal For: Aluminum, copper, and other non-ferrous metals.



Conclusion



At F&Q-Tech, we understand that the color of your CNC machined parts is just as important as their functionality. That's why we offer a variety of color surface treatment methods to ensure that your parts not only perform well but also look great. Whether you're looking for corrosion resistance, aesthetic appeal, or a combination of both, we have a solution for you.



Key Takeaways:



Electroplating is ideal for metals requiring high durability and a shiny finish.Anodizing is perfect for aluminum parts needing corrosion resistance and color stability.Powder Coating offers a wide range of colors and is highly durable.Chemical Coloring is cost-effective and suitable for stainless steel and copper alloys.Laser Coloring provides permanent, eco-friendly colors with high precision.Hot-Dip Galvanizing is best for steel parts needing long-lasting corrosion protection.By understanding the different methods and their applications, you can make an informed decision about which color surface treatment is right for your CNC machined parts. Contact us today to discuss your project and discover how we can help you achieve the perfect finish.



Call to Action



To ensure we deliver exactly what you envision, we require two crucial elements for our quoting process: detailed drawings and color swatches.

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Ready to explore the possibilities of color customization for your CNC machined parts? Contact us to learn more about our services and how we can help bring your vision to life.

Injection molding is a process widely used in manufacturing to produce a variety of plastic products. From simple daily necessities to complex automotive parts, the injection molding process plays an important role. This article will detail the four key stages of the injection molding process to help you better understand this process.

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In April 2025, Apple CEO Tim Cook said in an interview: "The core reason why Apple insists on manufacturing in China is not cheap labor, but China's irreplaceable 'skill density'." This view not only reveals the underlying logic of Apple's supply chain, but also reflects China's global competitiveness in the field of precision manufacturing. This article will deeply analyze how China has become the preferred partner for CNC processing and mold injection services for European and American companies by relying on its technical talent reserves, supply chain efficiency and innovation ecology.

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1. The core competitiveness of China's manufacturing: the transition from "cheap" to "skill density"

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1.1 “Skill Density” in Cook’s Eyes

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Cook has repeatedly stressed that the core advantage of China's manufacturing industry lies in its large-scale and systematic talent pool. For example, the number of mold engineers in a certain province in China can "fill several football fields", while the United States "can't even gather enough engineers for a meeting." This gap stems from:Education system support: China's vocational education system focuses on training technical workers, covering high-skilled fields such as CNC programming and mold design.Industry chain collaboration: From raw materials (such as aluminum alloys and engineering plastics) to precision processing, China has formed a "one-hour industrial circle" to achieve rapid response and cost optimization.

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1.2 The “micrometer-level” threshold for precision manufacturing

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Apple products require mold precision up to micron level (such as the surface fit of iPhone shell), which relies on the following technological breakthroughs:Popularization of 5-axis CNC machining: China's leading factories have widely used 5-axis linkage machine tools, which can process complex curved parts with an accuracy of ±0.01mm.Injection molding process innovation: For example, the glass panel produced by Lens Technology for Apple Vision Pro uses high-precision hot bending technology, with a yield rate of over 99%.





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2. Four major driving forces for European and American companies to choose Chinese suppliers



2.1 The ultimate balance between cost and efficiency

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Dimensions
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Comprehensive cost
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Delivery cycle
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Technical adaptability
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Chinese Manufacturers
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Labor + equipment depreciation costs are 30%-50% lower
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Average 2-4 weeks (relying on clustered supply chain)
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Support flexible production from prototype to mass production
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European and American local suppliers
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High labor cost, suitable for small batch customization
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Prefer standardized large-volume orders
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Complex parts take 6-8 weeks


Case:A German car brand transferred its aluminum alloy wheel CNC processing orders to China, reducing costs by 40% and shortening delivery time to 3 weeks.A US medical company commissioned a Chinese manufacturer to produce disposable endoscope housings by injection molding, which passed ISO 13485 certification and had a defect rate of less than 0.1%.



2.2 Green Manufacturing and Compliance



Carbon neutrality goal: China's leading suppliers (such as BYD and Luxshare Precision) have pledged to achieve carbon neutrality for Apple orders by 2030, using environmentally friendly materials such as recycled aluminum and bio-based plastics.Process optimization: Through AI-driven tool path planning, material waste in CNC processing is reduced, and the waste recovery rate exceeds 90%.





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3. The hidden advantages of China’s supply chain: Taking Apple as an example



3.1 Upgrading from “assembly” to “core technology”



Cook clarified: "The iPhone is not only 'assembled in China', its core components (such as glass cover and metal structural parts) rely on the precision processing capabilities of Chinese manufacturers." For example:Lens Technology: Provides super-ceramic glass panels for iPhone, with 4 times higher drop resistance, relying on nano-level CNC polishing technology.Everwin Precision: Uses 100% recycled aluminum to manufacture MacBook shells, taking into account lightweight and environmental protection requirements.



3.2 Intelligentization and Digital Empowerment



Industrial 4.0 factory: For example, BYD's "Using iPad to Produce iPad" project uses automated optical inspection (AOI) equipment to achieve real-time defect identification.Cross-border collaboration: Chinese manufacturers provide online quotation systems and production progress tracking platforms, and European and American customers can remotely monitor order status.



4. Cooperation Guide for European and American Enterprises: How to Select High-Quality Chinese Suppliers?



4.1 Key Evaluation Indicators



Certifications: ISO 9001 (quality management), IATF 16949 (automotive), ISO 13485 (medical).Equipment list: factories equipped with high-end machine tools such as DMG MORI and MAZAK are preferred.Intellectual property protection: Sign an NDA agreement and select compliant suppliers that have served Apple, Tesla and other companies.



4.2 Risk Avoidance Strategies



Phased cooperation: Start with small batch trial production (e.g. 500 pieces) to verify quality stability, and then expand to large-scale orders.Third-party quality inspection: CMM test report and material composition analysis certificate are required.



5. Future Trends: Challenges and Opportunities of Made in China



Challenges: low-cost competition in Southeast Asia, and the "nearshore outsourcing" policy in Europe and the United States (such as the US "CHIP Act").Opportunities:High-end technology: China's 5-axis CNC machine tool localization rate is expected to reach 29.2% in 2029, breaking the monopoly of Germany and Japan.Globalization of services: China-Europe Express and RCEP agreements reduce cross-border logistics costs, and door-to-door time is compressed to 15 days.



Conclusion：Cook's affirmation of Made in China confirms the core logic of "technological density" replacing "low cost" in the reconstruction of the global industrial chain. For European and American companies, choosing Chinese CNC processing and mold injection molding service providers is not only a cost consideration, but also a strategic investment in precision manufacturing capabilities and supply chain resilience.

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From the mobile phone case and electric toothbrush in your hand to the dashboard of the car, the precision parts of medical equipment, and even the parts of spacecraft, most of these seemingly different plastic products hide the same manufacturing technology - injection molding. This process, which was born in the late 19th century, has now become the "mainstay" of modern manufacturing. Why is it so popular? This article will reveal the secrets of injection molding from multiple dimensions such as efficiency, cost, and quality.



1. What is injection molding?



The principle of injection molding is not complicated: heat and melt plastic particles into liquid, inject them into the cavity of a metal mold under high pressure, and demold them after cooling and solidification to obtain a product that is consistent with the shape of the mold. The whole process is similar to "pour plaster", but with industrial precision control, it can achieve mass production of complex structures with millimeter-level accuracy.



2. Why choose injection molding? Five core advantages



King of production efficiency: producing finished products in minutes



Unlike traditional cutting or manual molding, the core advantage of injection molding lies in the efficient production of "copy and paste". After a set of molds is developed, the production cycle of a single part usually takes only tens of seconds to a few minutes. For example, the injection molding of an ordinary plastic water cup only takes 30 seconds, while an automated production line can produce tens of thousands of products 24 hours a day. This efficiency is irreplaceable in areas that require large-scale production (such as daily necessities and electronic accessories).Injection molding compresses the time dimension of traditional manufacturing to seconds. A set of ordinary molds can complete the entire process from mold closing, injection molding, pressure holding to demolding within a 10-second cycle, and it is easy for modern injection molding machines to produce 10,000 pieces per day. This efficiency revolution directly changed the logic of product development: an international toy company used high-speed injection molding technology in 2019 to shorten the new product launch cycle from the traditional 18 months to 7 months.In terms of cost control, injection molding shows amazing economy. After the car door handle adopts the injection molding process, the unit cost is reduced by 72% compared with metal stamping, and the weight is reduced by 60%. This cost advantage is exponentially magnified in large-scale production. A home appliance company has reduced the manufacturing cost of air purifier shells with an annual output of 3 million units by 21 million yuan by optimizing the injection molding process. The integration of automation systems and injection molding technology has given birth to a 24-hour "dark factory". In the injection molding workshop of a German auto parts factory, 128 injection molding machines are dispatched by the central control system to achieve unmanned operation of the entire process from raw material drying to finished product packaging. While reducing labor costs by 83%, the product defect rate is controlled within 0.12‰. In a smart factory, a 1,600-ton injection molding machine is performing "speed and passion". As the mold closes quickly, the molten plastic at 280°C instantly fills the mold cavity under a high pressure of 150MPa. After just 18 seconds, 64 mobile phone shells are neatly arranged on the conveyor belt. This magical production efficiency stems from the essential characteristics of injection molding: single molding and batch replication. Compared with the "subtractive manufacturing" of traditional mechanical processing, injection molding achieves one-time molding of geometrically complex structures through "additive manufacturing", which reduces the effective processing time of a single product by more than 90%. The standardized design of molds pushes efficiency to the extreme. Toyota's automotive interior parts production line in Japan uses a modular mold system. By simply replacing local inserts, the switching production of parts for different models can be completed within 2 hours. This flexible manufacturing feature enables the annual production capacity of a single production line to exceed 5 million pieces, which is equivalent to the birth of 10 precision parts every minute.



Cost dilution tool: the larger the quantity, the cheaper the unit



Although the initial development cost of the mold is high (ranging from a few thousand to hundreds of thousands of yuan), the cost per piece will drop sharply when the output reaches a certain scale. For example, the development cost of a mobile phone shell mold is 100,000 yuan. When 1 million pieces are produced, the cost of each mold is only 0.1 yuan; while the cost of 3D printing the same part may be as high as 5 yuan per piece. This "economy of scale" feature makes injection molding the optimal solution for mass production of millions of units. The initial investment in the mold is like a math problem: when the development cost of a certain electric toothbrush shell mold is 120,000 US dollars, the cost of producing the first shell is as high as 120,000 US dollars, but when the output reaches the million level, the mold cost is diluted to 0.12 US dollars per piece. This unique cost curve explains why 90% of consumer electronic products choose injection molding. According to a study by Boston Consulting Group in the United States, when the annual output exceeds 50,000 pieces, the comprehensive cost of injection molding is 76% lower than 3D printing and 89% lower than machining. In terms of material utilization, injection molding shows amazing advantages. By optimizing the hot runner system, a German company reduced the scrap rate of laptop shell production from 15% to 0.8%, saving 420 tons of engineering plastics each year. This "watertight" processing method, combined with an automated pickup system and online quality inspection, has built a nearly perfect production closed loop.



Complex structures “in one go”



Modern injection molding technology can achieve "integrated molding", directly manufacturing complex structures that traditionally require multiple parts to assemble (such as flip covers with movable hinges and hollow pipes inside). Take the automobile intake manifold as an example. Traditional metal parts require more than 20 parts to be welded, while injection molded nylon parts can be molded in one go, reducing weight by 40% and providing better performance.



Highly adaptable materials: from potato chip packaging to rocket parts



There are more than 10,000 types of plastics compatible with injection molding: General-purpose plastics (such as PP and ABS) are used in daily necessities; Engineering plastics (such as PEEK and nylon) are resistant to high temperatures and corrosion and can replace metals; Biodegradable materials (such as PLA) cater to environmental protection trends; Even metal powders and ceramic particles can be processed through "metal/ceramic injection molding" (MIM/CIM) technology. This diversity allows injection molding technology to span multiple fields such as people's livelihood, medical care, and aerospace. The performance breakthrough of engineering plastics is redefining the possibilities of materials. The strength retention rate of PPSU material at 280°C exceeds 85%, successfully replacing metal to manufacture steam valves; the specific strength of carbon fiber reinforced PEEK material is 3 times that of titanium alloy, and has been used in spacecraft load-bearing structures. The emergence of these special materials has enabled injection molding products to continue to penetrate from the field of daily necessities to high-end manufacturing. The green material revolution promotes the sustainable development of injection molding technology. The application of bio-based PLA materials in the field of tableware has reduced the carbon footprint of a single lunch box by 68%; chemical recycling PET technology has achieved closed-loop production, and a beverage bottle manufacturer has reduced the use of 32,000 tons of virgin plastic each year through this technology. The combination of material innovation and environmental protection needs is reshaping the ecological logic of the entire industrial chain. Customized matching of materials and processes opens a new era. The combination of liquid silicone (LSR) and micro-foaming technology makes car seats both supportive and breathable; the synergy of conductive polymers and two-color injection molding technology allows the smart bracelet antenna and shell to be perfectly integrated. This precise material and process matching has given birth to unprecedented product forms.Standing at the threshold of Industry 4.0 and looking back, injection molding has evolved from a simple manufacturing technology to a core engine driving innovation. This technology is breaking through the boundaries of physics and chemistry and transforming material possibilities into real productivity. When 3D printing triggers people's romantic imagination of manufacturing, injection molding silently supports the construction of the material world of modern civilization with a hundred times the efficiency and precision of the former. In the future, with the deep integration of smart materials and digital twin technology, injection molding may evolve into a more amazing form and continue to write the efficiency legend in the history of human manufacturing. In the Shenzhen Materials Laboratory, engineers are debugging PEEK composite materials containing 35% glass fiber. This special plastic that can be used for a long time at 260°C is formed into drone structural parts through micro-foaming injection molding technology, which reduces weight by 20% and increases strength by 15%. Modern injection molding technology has broken through the traditional cognitive boundaries: liquid silicone (LSR) injection molding makes baby pacifiers both safe and flexible; metal powder injection molding (MIM) creates clock gears thinner than a hair; biodegradable plastics are reshaping the ecology of the packaging industry. Design freedom is another breakthrough dimension. A medical company uses stacked mold technology to achieve 96-cavity insulin pen parts production on conventional equipment, with wall thickness differences controlled at ±0.02mm. Conformal cooling water channel technology allows mold temperature control accuracy to reach ±1°C, making the optical performance of lens products comparable to glass products. These technological innovations continue to expand the imagination of industrial design. Standing at the crossroads of the era of intelligent manufacturing, injection molding is undergoing a digital transformation. IoT sensors monitor the cavity pressure and temperature curve in real time, artificial intelligence algorithms autonomously optimize process parameters, and 3D printing technology subverts traditional mold manufacturing methods. In a lighthouse factory in Jiangsu, there are only three engineers in the entire injection molding workshop monitoring 20 smart devices, and the per capita output value is 15 times that of traditional workshops. This evolution not only continues the vitality of injection molding, but also spawns green solutions such as bio-based plastics and chemical recycling in the context of carbon neutrality, allowing this century-old process to continue to rejuvenate. From daily necessities to cutting-edge technology, injection molding is like a master key, constantly opening up new possibilities for modern manufacturing.



Accuracy and consistency far exceed manual



High-precision molds (error ±0.005mm) combined with computer control can ensure that the dimensions of millions of products are almost exactly the same. Taking medical syringes as an example, the clearance between the injection-molded syringe barrel and the piston must be controlled within 0.01mm, which is impossible to achieve with manual production. The processing accuracy of modern injection molds has reached the micron level, which is equivalent to controlling the error to no more than a grain of sand on an area the size of a football field. This breakthrough in precision has enabled revolutionary innovation in the medical field: the precision gear assembly of the implantable insulin pump has achieved a matching tolerance of 0.02mm through micro-injection molding technology, which is smaller than the diameter of a red blood cell. Complex structure integrated molding technology is rewriting product design rules. The latest folding wing structure launched by a drone manufacturer uses gas-assisted injection molding technology to integrate 17 traditional parts into one integral component, reducing assembly processes by 94% and increasing structural strength by 300%. This breakthrough in design freedom allows product engineers to boldly realize innovative ideas that were unimaginable in the past. Innovations in surface treatment technology have allowed injection molded parts to break through material limitations. IMD (in-mold decoration) technology allows mobile phone shells to transfer textures simultaneously during the injection molding process, and its wear resistance is 5 times higher than that of traditional spraying processes; the application of nano-coating technology allows plastic lenses to reach the light transmittance of optical glass. These breakthroughs continue to expand the application boundaries of injection molded products.



3. How does injection molding promote industrial upgrading?



Miniaturization revolution: Nano-molding technology (NMT) allows the metal frame of the mobile phone and the plastic antenna to be molded into one piece, achieving "zero interference" with 5G signals.Green manufacturing: Hot runner technology reduces waste, and bio-based plastics are recycled, making injection molding more environmentally friendly.Intelligent future: AI monitors injection pressure and temperature in real time, automatically optimizes parameters, and increases the yield rate to more than 99.9%.



4. Is it suitable for all scenarios?



Injection molding is not a panacea. Small-batch production (such as customized samples) may not be as cost-effective as 3D printing due to the high mold cost; oversized parts (such as wind turbine blades) require other processes. However, with the development of mold 3D printing and rapid mold change technology, these limitations are gradually being broken.



Conclusion: The “Hidden Champions” of Manufacturing



From the simple injection molding of celluloid in the 19th century to today's intelligent and green precision manufacturing, injection molding has defined modern industrial aesthetics with "efficiency, precision and flexibility". The next time you pick up a plastic product, think about it: behind this seemingly ordinary little object, there may be a set of molds worth millions and a century-long technological evolution journey.

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The science of injection molding machine tonnage: the watershed between small tonnage and large tonnage

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In the field of plastic injection molding, the "tonnage" of an injection molding machine directly determines its capacity limit. Tonnage does not refer to the weight of the entire machine, but the size of its clamping force, measured in tons (T). This parameter represents the maximum closing force that the clamping system of the injection molding machine can exert, which is used to resist the huge expansion pressure generated when the molten plastic is injected into the mold. If the clamping force is insufficient, the mold will be stretched open, resulting in flash burrs; and excessive tonnage will cause energy waste and equipment loss.The calculation of clamping force follows the core formula:Clamping force (T) = product projection area (cm²) × mold pressure (kg/cm²) × safety factor / 1000The mold pressure depends on the material properties:Ordinary plastics (such as PP, PE): 250-350 kg/cm²Engineering plastics (such as PC, nylon): 350-500 kg/cm²The safety factor is usually 1.1-1.2.

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1. The core differences between injection molding machines of different tonnages

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Injection molding machines can be divided into four categories according to tonnage, which have significant differences in mechanical structure, application scenarios and technical requirements:（1）Small machine (30-100 tons)Structural features: mostly vertical or angular design, mainly fully electric drive, small footprintInjection volume: usually ≤200 grams (based on PE)Typical applications:Electronic connectors (USB interface, SIM card tray)Precision gears (clocks, micro motor parts)Medical equipment (syringe needles, test tubes)Advantages: high precision (repeat error ±0.01mm), energy saving (60% less power than hydraulic presses), no oil pollution（2）Medium-sized machine (150-500 tons)Mainstream machine: hydraulic or hydraulic-electric hybrid drive, horizontal structureInjection volume: 300-2000 gramsApplication scenarios:Household appliance housing (rice cooker, vacuum cleaner housing)Daily necessities (washbasin, chair, toy)Automotive interior parts (dashboard frame, door handle)Technical highlights: Can be equipped with multi-color injection molding system (such as P-type/L-type double shot) to achieve dual-material composite molding（3）Large machine (600-1000 tons)Structural features: two-plate clamping mechanism, enhanced rigidity and mold opening spaceInjection volume: 2500-5000 gramsTypical products:Logistics pallet (1200×800mm standard size)Automobile bumperLarge trash canChallenge: Need to cooperate with mold temperature control system to prevent shrinkage of thick-walled parts（4）Ultra-large machine (>1000 tons)Representative models: Haitian 1600T, Fuqiangxin 1900T three-color machineCapacity indicators: up to 4000 tons, injection volume exceeds 20kgApplication areas:Automobile instrument panel (one-piece molding)Yacht deck partsLarge turnover box (volume>1000L)Innovative design: horizontal two-color machine (H type) with overlapping mold technology, production capacity increased by 70%

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Table: Comparison of injection molding machine tonnage and key parameters

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Tonnage range
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Clamping force (T)
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Injection volume (g)
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Screw diameter(mm)
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Typical mold structure
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Minicomputer
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30-100
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≤200
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25-40
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Toggle
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Medium-sized machine
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150-500
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300-2000
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45-70
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Toggle/Two-Plank
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Mainframe
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600-1000
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2500-5000
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75-110
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Two-plate
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Large Scale Machines
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>1000
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>5000
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≥120
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Two-plate enhanced


2. Core principles and application scenarios of tonnage selection



The cost of failed selectionInsufficient tonnage: product flash and size deviation (a mold that is stretched 0.1mm can lead to scrapping)Tonnage is too large: energy consumption increases by 30%-50%, the risk of mold deformation increases, and mold exhaust difficulties lead to burning



Four-step scientific selection methodCalculate clamping forceTake the car bumper as an example: the projected area is 1200×600mm=7200cm², and the pressure in the PC mold is 400kg/cm²Theoretical clamping force = 7200×400×1.2/1000≈3456T → Select the 3500T modelTest toleranceMold size ≤ tie rod spacing (such as the tie rod spacing of the 1000T machine is usually 1200×1200mm)Mold thickness ∈ [minimum mold thickness, maximum mold thickness] (for example: the mold thickness range of 350T machine is 150-450mm)Ensure demoulding spaceMold opening stroke needs to be > product height×2 + runner length (deep cavity parts need to add an additional 20% margin)Match injection systemFinished product weight should be ≤ Theoretical shot volume × 75% (leave a safety margin)For thin-walled parts, choose a small screw (high pressure and high speed), and for thick-walled parts, choose a large screw (high plasticizing capacity)Industry scenario applicationElectronic industry (below 100T): Connectors use a 30mm diameter screw, and the shot speed ≥300mm/s ensures fillingHome appliance industry (300-800T): Air-conditioning panels use hot runner molds + 650T machines to reduce runner wasteAutomotive industry (>1000T): Door panels use a double-station turntable three-color machine to achieve one-time molding of substrate + soft glue + logoMedical industry (50T fully electric): Syringe production is equipped with a Class 100 clean room to avoid hydraulic oil pollution



3. Future trends in technology evolution and tonnage selection



The selection of injection molding machine tonnage is undergoing three major technological changes:Energy-saving driveAll-electric injection molding machines (such as FANUC Roboshot) replace hydraulic presses below 100T, reducing energy consumption by 60%; the penetration rate of hybrid technology in large machines increases (such as Haitian MA series)Intelligent control systemIoT module monitors clamping parallelism in real time (deviation of >1000T machine needs to be ≤0.1mm/m)AI algorithm dynamically optimizes the pressure holding curve, reducing the molding cycle of large-tonnage machines by 15%Specialized developmentMicro injection molding machine (<10T): used for medical microfluidic chips, injection accuracy ±0.002gMulti-component large machine: such as Fuqiangxin FB-1900R three-color machine, turntable diameter 2250mm, serving the integrated molding of automobile lampshadesIn the future, with the application of new materials (such as carbon fiber reinforced plastics), the clamping accuracy requirements for high-tonnage machines will be further improved, and modular design will make tonnage adjustment more flexible-by replacing the screw assembly, the same clamping unit can cover the injection range of ±30%.



4. Conclusion



The selection of injection molding machine tonnage is like deploying troops for a battle: too little will not be enough, and too much will be a waste of money and effort. From a connector the size of a fingernail to a car bumper several meters long, the difference in tonnage is the result of the deep collaboration of material science, mechanical design, and control algorithms. In the future, with the advancement of energy-saving technology and intelligence, tonnage selection will no longer be based solely on empirical formulas, but will be dynamically optimized based on real-time data, pushing plastic molding into a new era of "tailor-made".