With the development of the aerospace industry, the demand for aerospace fasteners has increased rapidly. As aerospace fasteners are applied under an environment of high temperature, high pressure, and high intensity, their quality requirements are also particularly high. Here, we introduce some useful knowledge about aerospace fasteners.
The need for aircraft fasteners has increased dramatically as the aerospace sector has grown. Because aerospace fasteners are used in high-temperature, high-pressure, and high-intensity environments, their quality standards are exceptionally stringent. In this section, we will discuss some useful information concerning aircraft fasteners. A fastener is a type of mechanical device that connects two or more parts together. The scope of application is extremely broad. Aerospace fastener is a fastener that is specifically designed for use in the aerospace sector. It uses materials with unique qualities or applications.
Aerospace fasteners are commonly found in aircraft, satellites, and rockets. It is a standard high-end fastener. It is also a vital basic component of aerospace aircraft. The performance criteria are substantially higher than for other types of fasteners. There are several typesof aerospace fasteners, each with its own set of requirements and types to fulfill the unique needs of various materials and constructions.
What are the different types of aerospace fasteners?
1. Aerospace fasteners are divided as detachable and permanent fasteners based on their ability to be removed. Bolts, screws, and nuts are among the detachable fasteners. Permanent fasteners include high-locking nuts, rivets, and other similar items.
2. Aerospace fastener types include bolts, screws, nuts, single-sided fasteners, special fasteners, and so on.
3. Carbon structure steel fasteners, alloy steel fasteners, stainless steel fasteners, high-temperature alloy fasteners, aluminum alloy fasteners, titanium alloy fasteners, non-metal fasteners, and so on are the materials used in aircraft fasteners.
4. It can be split into single-sided fasteners and double-sided fasteners based on the variations in the requirements of the aerospace assembly operation.
Commonly used important aerospace fastener
Rivet fasteners
The most essential selection parameters for rivet fasteners used in aircraft are quality assurance and lightweight. It is one of the most common airplane fasteners. Aluminum alloy, stainless steel, heat-resistant alloy, titanium alloy, and other materials are used. The majority of rivets are made of composite materials such as aluminum alloy and titanium alloy. With the continual increase of rivet material intensity, support rivets used in corresponding vital sections, such as dual metal rivets and high shear rivets, have been created, and their strength can reach the intensity of titanium alloy high lock bolts.
Bolt fasteners
The bolt fastener, which includes regular bolts, high lock bolts, and tapered bolts, is the most commonly used fastening for bearing the bigger sections of the aircraft. A high lock bolt is a single-sided thread fastener that is commonly used in the aerospace sector. Weight loss is an essential signal in airplane design. High-ratio intensity materials can be used to substitute large-sized fasteners with lesser intensity. Furthermore, anti-fatigue, corrosion resistance, rigidity, brittleness, compatibility, heat resistance, and other features must be taken into account.
Nut fasteners
Nut fasteners are used in conjunction with bolts. They come in a range of structural forms to satisfy the needs of various aerospace applications, such as hex nuts, bihexagon nuts, bracket nuts, barrel nuts, and high lock nuts, the majority of which feature a self-lock construction. The hexagonal nut has been extensively used on the airplane. Bihexagon nuts are commonly seen on engine and high-strength bolts.
Single-sided fastener
In the open areas of the airplane, there are two types of fastening pieces. The bracket nut/bolt and rapid unloading fastener used in removable elements such as the airplane hatch is one example. The other is a single-sided nail, which is utilized in the permanent connection section. The screw thread nail is specifically created for the composite material structure, which can increase sealing and anti-fatigue performance.
Special fasteners
Ring grooved nails are a form of double-sided permanent fastener that is inserted with single-sided riveting. They are frequently utilized in Boeing and Airbus aircraft. The fast unloading fastener is mostly used to connect the cover to the hatch. It can perform fast loading and unloading duties and has a range of structural configurations. It has stringent reliability requirements. Composite fasteners, such as rivets, bolts, screws, and nuts, are formed of composite materials. It is a suitable aerospace fastener used to tackle problems in the aircraft such as weight, strength, corrosion, lightning strike, and other challenges.
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What should you consider when selecting screws for your next project? The question is that technicians who assemble various products ask themselves when trying to find an ideal kind of custom screw for their work. Screw fasteners are distributed to different industries from automotive, construction, transportation to medical, mining, and furniture industries, custom screw options continue to revolutionize the fastening market.
Advantages of choosing custom screw
Made-to-Order
The availability of a variety of custom screw options offers an endless list of possibilities for product designs. You can now order your fasteners with the preferred shape, head-size, length, and even threading size. Understanding these primary features allows development engineers to come up with better quality products for their companies.
Mechanical Advantages
The right customized fastener offers benefits on tailored installation torque required. Torque refers to the forces that move the screw and rotates it. Customizable fastener options allow the product developers to use the right amount of torque during the product fastening. This way, you can avoid breaks and loosening of other parts during assembly. Custom SEMS screws come with built-in washers to secure the screw in place, increasing product safety.
Resistance to Rust
Fasteners are subject to corrosion and loosening through wear and tear. Proper finish coatings of custom screws help to keep the screws resistant to corrosion. The advantage of custom screw options is that you choose the proper coating for your product. Chrome and zinc coatings are standard in the micro screw industry. The layers offer ideal polished finishes that have improved resistance to wear in, especially in tough environments.
Strength
Custom screw options come in different shapes and sizes, and in most cases, this determines their strength. A fastener is only useful if it can hold the screwed products firmly without bending or breaking. Customizable options provide an opportunity for you as a manufacturer to select the right threading and thickness of the screws. You can also select the correct thread depth for maximum robustness and minimized radial stress.
Safety Standards
The right machine screw assures improved security and performance for your products. Since 1927, the American National Standards Institute has provided manufacturing grades for all fasteners. The set quality ensures that the quality of the custom screws is not compromised, which in turn guarantees better product quality.
Right Materials
The use of custom screw options provides an opportunity to select the best materials depending on your products. Approximately 90% of all custom micro screws are made of stainless steel. Stainless steel has better tensile strength and is more durable than many other materials. You may also use bronze and brass alloys with increased resistance to corrosion. Aluminum is lightweight and customized for lighter machine parts and devices.
Various types of materials used in the making of custom screws.
Here are the material characteristics that you should consider to improve your custom screw sourcing
The material's ability to resist corrosion
When choosing materials for screws, you should consider whether the screws environment will be corrosive. Materials with high corrosion resistance such as steel are ideal for micro screws that will likely get exposed to corrosive conditions.
Mechanical properties of the material
Some metals are brittle and easy to bend and scratch. When such metals get used in making screws, it becomes hard to screw or unscrew some tight miniature screws. As such, you should look at the specific alloy strength of a material to determine whether the material can bear with various damaging forces.
Aesthetics
Aesthetics is the least important factor when compared to screw strength and durability. But it’s also essential where screws get used on prominent decorative pieces or devices. For example, a copper custom screw or copper-plated screw may have a better appearance when used on a prominent place than would be the case for a steel custom screw used in the same place.
Operations of screw fabrication
When choosing a material to make a screw, you should also look at the material’s ability to get processed with ease. Things to look at should include the strength of the material to be cold-headed, welded, or machined.
The cost of the screw material
The value of the metallic alloy to make the micro screws gets determined by considering factors such as the effective life-expectancy of the finished screws, the installed price, and the initial alloy cost. When materials match in strength, durability, fabrication needs, and mechanical properties, then cost, and aesthetics become the second-last considerations to make.
The availability of the material
The availability of the material is the last consideration to make. No matter how good a material is in making micro screws, if you can’t find the material in enough quantities, then you’re less likely to choose such material for your micro screw fabrication.
The Most Preferred Screw Material in the Making of a Custom Screw
Stainless steel material for fastener is the most affordable and abundant. It is a versatile material that you can combine with other metals to create durable alloys. Minerals that you can use to make steel alloys include silicon, cobalt, tungsten, copper, molybdenum, nickel, chromium, and manganese. It is hard, malleable, and durable.
Your custom screw material options are extensive. Make careful considerations when selecting material for your screws.
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As society advances, the diversity of stamping products continues to expand, finding applications across various industries. To enhance efficiency, scrutinize work quality, and ensure product excellence, meticulous inspection of stamping parts becomes imperative. This article sheds light on prevalent inspection methods for stamping parts.
1. Flexible Gauze Mesh Grinding
Process:
Begin by cleansing the outer surface with clean gauze.
Employ flexible gauze mesh to systematically grind the entire surface of stamping parts along the longitudinal axis. This approach facilitates the identification of any pitting or indentations.
2. Touch Test
Procedure:
Clean the outer surface with gauze.
Don touch gloves and gently touch the stamping parts along the longitudinal axis, assessing the presence of discernible burrs, indentations, scratches, rough edges, etc.
Note: This method relies on the inspector's experience and is a swift yet effective examination technique.
3. Visual Inspection
Steps:
Inspect the surface for rust, cracks, sand holes, slag inclusions, burrs, or blemishes.
Quality parts exhibit precision and a lustrous finish. Crucial components demand higher precision and stringent anti-rust packaging.
Check for secure bonding between parts. In multi-part assemblies, tight adhesion, gluing, or welding is essential to prevent looseness.
Note: Visual inspection primarily identifies surface irregularities and macro defects in stamping parts.
4. Grinding with Oil Stone
Protocol:
Clean the surface using gauze.
Employ an oilstone (20 × 20 × 100mm or more), and smaller oilstones for areas with curves or challenging access.
Note: Opt for a fine-grained oilstone; the grinding direction should align with the longitudinal axis. Horizontal grinding may complement certain spots.
5. Inspection with Special Tools
Method:
Place metal stamping parts into inspection tools and follow the tool manual to perform the inspection.
6. Oiling Inspection
Procedure:
Clean the surface using gauze.
Evenly apply oil across the stamping surface in the same direction using a clean brush.
Inspect the oiled parts under strong light.
Note: This technique effectively reveals minor pits, dents, ripples, etc. on the stamping parts.
7. Adopt Approximate Process Testing
In actual production, process tests akin to stamping operations—such as tensile and bulging tests—are often utilized to assess material stamping performance, ensuring high product quality and qualification rates.
Characteristics of Stamping Parts
Rapid Process Completion: Stamping accomplishes feeding, stamping, delivery, and waste disposal in minutes, yielding tens or hundreds of parts per minute.
Uniformity and Precision: Unified molds generate uniform products with minimal errors and high dimensional accuracy. Random sampling of such products exhibits a weighing error below 3%.
Stamping Equipment
Mechanical presses are predominantly used for stamping, along with hydraulic presses for thick plates. Combining conveying machinery, die libraries, and rapid die-changing devices, automated stamping lines boost productivity, supported by computer program control.
Impact of Stamping Molds
The precision and structure of stamping molds directly influence part formation and accuracy. Mold manufacturing cost and lifespan significantly impact part quality and cost. Mold design requires time, which extends preparation for new stamping parts.
Trends in Stamping Mold Development
Standardized mold bases and guide pieces.
Innovation in simple molds (for small batches), composite molds, and multi-station progressive molds (for large-scale production).
Advancements in rapid mold change devices, aiming to apply advanced stamping technology to diverse production scales.
The goal is to streamline production preparation, making advanced stamping technology feasible for both mass production and small-batch, multi-variety production scenarios.
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CNC machining is a sophisticated process involving various machine tools, materials, cutting tools, and methods. Drawing from extensive experience in actual production processes, we share valuable tips for optimizing CNC machining tools. These insights cover determining cutter points, selecting tool paths, and choosing the right CNC machining tools for different applications.
Tip 1: Determining Cutter Points in CNC Machining Tools
Set the cutter point on the part to be processed, ensuring it is a reference position or a finished point.
Establish a relative cutter point position with a fixed dimension relationship to the positioning reference.
Selection Principles:
Easy to find
Easy programming
Small cutter point error
Convenient inspection during processing
Set the origin position of the workpiece coordinate system based on the cutter point after clamping, ensuring consistency with the programming coordinate system.
Tip 2: Selecting Tool Paths in CNC Machining Tools
Consider the machining accuracy requirements of parts when determining the tool path.
Seek the shortest processing path to reduce empty tool time and improve efficiency.
Reduce the number of program segments.
Ensure continuous processing of the final contour using the last tool to maintain workpiece contour surface roughness.
Carefully consider the forward and backward path of the tool to minimize tool marks and avoid scratching the workpiece during vertical cutting.
Tip 3: Choosing CNC Machining Tools
Select a non-regrinding carbide end milling cutter for plane milling.
Use end milling cutters for rough milling and continuous cutting along the workpiece surface.
Utilize ball cutters and round cutters for curved surfaces and variable bevel profiles.
Adjust cutting parameters (cutting depth, spindle speed, and feed speed) based on the general principle of less cutting and fast feeding.
Conclusion:
These tips, derived from years of CNC machining and surface finishing experience, aim to enhance the efficiency and precision of the process. At KENENG, we specialize in high-precision metal shell and precision hardware CNC cutting, offering a range of CNC processing services, including milling, turning, drilling, threading, tapping, EDM, wire EDM, custom finishing, prototyping, small batch production, and modification of existing parts. Our commitment to quality includes the use of high-precision measurement tools and advanced video equipment for inspections, ensuring only qualified products reach our customers. Choose KENENG for reliable CNC machining services and products tailored to your needs.
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In various industrial sectors like automotive, aerospace, construction, and manufacturing, the significance of heat treatment in the production of bolts cannot be overstated. By undergoing a carefully regulated heat treatment process, bolts can significantly enhance their mechanical properties to meet specific criteria, ensuring reliability and performance in diverse applications.
Heat treated bolts are the result of a controlled heat treatment technique designed to alter their microstructure, thereby improving their mechanical characteristics. This crucial manufacturing step greatly influences the performance and durability of bolts, making them indispensable in various industries.
The process involves subjecting the bolts to high temperatures followed by rapid or gradual cooling, depending on the desired properties. This manipulation of temperature and cooling rate can enhance crucial qualities such as strength, ductility, toughness, wear resistance, and corrosion resistance.
One of the primary advantages of heat treated bolts lies in their increased strength. Through heat treatment, bolts can exhibit heightened hardness, toughness, and wear resistance, making them suitable for demanding applications that require superior load-bearing capacity, such as heavy machinery and structural components.
Furthermore, heat treatment process improves the ductility of bolts, reducing the likelihood of brittle fracture or failure. This increased ductility ensures that bolts can flex under stress without breaking, enhancing their dependability and safety, particularly in harsh operating conditions.
Corrosion resistance is another key benefit of heat treated bolts. By undergoing heat treatment, bolts can better withstand rust, oxidation, and other forms of corrosion, making them ideal for applications exposed to extreme environmental conditions or chemicals, as seen in marine, automotive, and aerospace industries.
Moreover, heat treatment enhances the fatigue resistance of bolts, crucial for withstanding repeated or cyclic stress. Bolts treated through this process exhibit improved fatigue strength, enabling them to endure multiple stress and load cycles without fracturing or failing, essential for applications subject to dynamic or variable loads.
Various heat treatment methods are employed in the production of bolts, including quenching, tempering, annealing, and normalizing, each offering distinct advantages in enhancing bolt properties.
Quenching involves rapid cooling of heated bolts in a quenching liquid to increase hardness and wear resistance, although it may lead to brittleness, often mitigated through subsequent tempering.
Tempering, on the other hand, involves controlled reheating and cooling to improve ductility and toughness, striking a balance between strength and flexibility.
Annealing entails slow cooling of bolts after heating to relieve internal stresses, enhance machinability, and reduce hardness, ideal for applications requiring ductile and durable bolts.
Normalizing, similar to annealing but with air cooling, refines grain structure to enhance strength and fatigue resistance, commonly used in heavy machinery and structural components.
In summary, heat treated bolts play a crucial role in various industries, offering superior strength, corrosion resistance, and fatigue resistance. Understanding the principles and methods of heat treatment is essential for ensuring optimal bolt performance across diverse applications, contributing to the reliability and safety of industrial systems.
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Spring is everywhere in various machines. From consumer goods to heavy industrial equipment, as long as you remove anything involving mechanical devices, you may find the spring inside, which is a mechanical storage device.
Cylindrical Helical Spring
Circular cross-section type
It is a compression spring with a circular section.
The characteristic line is linear, stable in stiffness, with a simple structure, convenient manufacturing, and wide application. It is mostly used as a buffer, vibration reduction, energy storage, and control movement in mechanical equipment.
Rectangular cross-section type
Under the same space conditions, the cylindrical spiral compression spring with a rectangular cross-section has greater rigidity and more absorption energy than the circular section type. The characteristic line is closer to the straight line and the stiffness is closer to the constant.
Flat-shaped section type
Compared with the circular cross-section type, the cylindrical helical spring with a flat-shaped section has large storage energy and large compression. Therefore, it is widely used in the installation space such as engine valve mechanisms, clutch, and automatic transmission.
Variable pitch type
When the load is increased to a certain degree, as the load increases, the spring gradually tightens the spacing from the section, and the stiffness gradually increases. Therefore, its autobiography frequency becomes a variable value, which has a good effect on eliminating or easing resonance and is widely used for high-speed load-changing mechanisms.
Multi-wire type
The material is steel wire rope. When it is not loaded, the contact between the steel wires is relatively loose. When the external load reaches a certain degree, the contact is tight and the spring rigidity has been increased. It is widely used in weapons and aero motors.
Extension Spring
The performance and characteristics of extension springs, are the same as the cylindrical helical spring with a circular cross-section. It is mainly used in situations under tensile load.
Torsion Spring
The torsion spring is under the torsion load, mainly used for compression, energy storage, and the elasticity of the transmission system. It has a linear characteristic line and wide applications, such as measuring metering and the compulsory air valve closure mechanism.
Conical Coil Spring
The role is similar to the variable pitch cylindrical helical spring. After the loading reaches a certain degree, the spring is gradually tightened from the large coil to the small coil. The stiffness increases gradually and the natural frequency is variable. It is conducive to eliminating or easing resonance and the anti-resonance capacity is strong. This spring structure is compact and stable. It is mostly used to withstand large loads and vibration reduction. For example, suspension springs are applied in heavy vibrating screens and automobile transmissions.
Spiral Spring
Compared with other springs, the spiral spring can absorb larger energy in the same space, and the friction between the plates can be used to attenuate vibration. It is often used to absorb thermal expansion deformation. The disadvantage is that the gap between the board is small and difficult to quench and the spray treatment cannot be performed. In addition, the manufacturing accuracy is not high enough. It can be used as a measuring element and pressing element.
Torsion Bar Spring
The torsion bar spring has a simple structure, but the requirements for the quality of materials and manufacturing accuracy are high. It is mainly used as a suspension spring for cars and small vehicles.
Ring-shaped Spring
The ring spring is widely used in occasions that need to absorb large energy but is limited by space, such as springs for locomotive traction devices, and buffer springs for cranes and cannons.
Leaf Spring
A leaf spring is a metal piece that has a rectangular cross-section, which is mainly used for situations when the loading and deformation are not large. It can be used as a sensitive element in the detection instrument or automatic device.
Plate Spring
The plate spring is laminated of multiple spring steel plates. It is widely used as a suspension device in cars, tractors, and trains, as a role of buffer and vibration reduction.
Rubber Spring
Due to the small elastic modulus of rubber springs, it can get greater elastic deformation, and it is easy to achieve the required non-linear characteristics. The shape is not restricted and the rigidity of each direction can be freely selected according to the design requirements. The rubber spring can withstand multi-directional loads at the same time, so it can simplify the structure of the system. The application of rubber springs on machinery equipment is increasing.
Rubber-metal Spring
The characteristic line is gradually increased. This rubber-metal helical spring has a larger rigidity compared to the rubber spring and has larger damping compared to metal springs. Therefore, it has the advantages of large loading capacity, strong vibration reduction, and wear resistance, suitable for suspension structures for mining machinery and heavy vehicles.
Air Spring
Air spring is a non-metallic spring that uses the compression of air to achieve elastic effects. It is widely used in vehicle suspension device, which can greatly improve the power performance of cars, so air spring is widely used on cars and trains.
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Springs are commonly found in everyday items such as washing machines, remote controls, fitness equipment, and bicycles. However, it's important to understand the characteristics and properties of the commonly used springs.
Characteristics of Compression Springs:
Compression springs are manufactured by winding separate helical turns, allowing each turn to have a gap or pitch. This design enables the spring to contract under force while maintaining tension towards both ends.
To avoid friction and fatigue damage, a gap must be reserved between the effective turns of the compression spring when subjected to maximum load.
The free length of the spring should include the actual length of the spring, the gap, and the amount of deformation.
Smoothing the surface of the compression spring increases the contact surface, aiming for around 60-80% contact.
Compression springs have various end treatments, including not being tight or smoothed, not being tight but smoothed, being tight but not smoothed, and being tight and smoothed.
Compression springs are widely used in electronics, motors, computers, automobiles, bicycles, and various industries. They are easy to design and manufacture.
Characteristics of Extension Springs:
Tension springs are wound into closely spaced helical coils or pitch coils. They stretch outward and maintain the force of shrinking toward the middle when subjected to external force.
Extension springs have different types of hooks, such as English hooks, German hooks, side ear hooks, and fishtail hooks.
Extension springs come in various shapes, including straight cylinders, hooks, and other variants, depending on the design.
Extension springs can be used as the reverse of compression springs and find wide applications. However, operational control is slightly more complex compared to compression springs.
Characteristics of Torsion Springs:
Torsion springs are divided into single torsion springs and double torsion springs. They are often inserted into pins or shafts and generate torsional force along the axis, causing the spring to coil or loosen when external force is applied.
Double torsion springs can be outer or inner double torsion with closed or separated circles. The ends of the spring can have hooked or straight torsion arms.
Torsion springs have complex design principles compared to other spring types, and various types of changes make the design more challenging.
Characteristics of Disc Springs:
Disc springs, such as DIN2093, are characterized by their small size, high load capacity, convenient combination and use, and efficient load transmission.
Disc springs can be combined in single-piece involution, multi-piece superimposed combinations, or mixed combinations to achieve various curves.
Disc springs are widely used in industries such as defense, metallurgy, engineering, power, construction, and more. They excel in applications like molds, support hangers, clutches, brakes, buffer devices, bearing preload, safety overload devices, and industrial machinery.
Disc springs adhere to standards like DIN2093 and GB/T1972-2005.
Understanding the characteristics of different springs helps in choosing the right type for specific applications and ensures optimal performance in various industries.
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The pop rivet, a dynamic variant of the traditional rivet, soars into prominence as a single-sided riveting solution. This innovative fastener necessitates a unique tool—the rivet gun (available in manual, electric, and automatic variants)—to facilitate its assembly.
Tailored for scenarios where conventional rivets prove cumbersome due to their dual-sided application, the pop rivet finds its niche across diverse sectors. Its widespread utility encompasses domains like construction, automotive manufacturing, maritime ventures, aviation, machinery, electrical appliances, furniture crafting, and an array of product fabrication.
Advantages Propelling Pop Rivet Equipment
The pop rivet's versatility lies in its capacity for swift and expansive riveting. This characteristic has galvanized processing and manufacturing industries nationwide. Key advantages encompass a broad scope for single-sided riveting, expedited installation, substantial clamping force, heightened seismic resistance, and robust locking prowess.
A Glimpse into the Standard Pop Rivet Installation Process
Embed the rivet within the nozzle of the rivet gun, guiding it into a pre-drilled aperture.
Activate the tool, prompting the rivet to expand and unfurl, snugly fitting into the void within the workpiece.
As the load attains a predetermined magnitude, the rivet's head breaks flush, while the rod secures itself within the rivet, locking the connection firmly.
Decoding the Ingenious Mechanism of the Pop Rivet
The pop rivet's operational essence hinges upon exerting force from within to outwardly pull its core head. Mastery over this mechanism holds the key to optimizing pop rivet application.
The open-type round-head pop rivets reign supreme in ubiquity. For scenarios demanding sleek surfaces, countersunk head pop rivets come to the fore. Conversely, closed-type pop rivets cater to high-load contexts and sealing prerequisites.
Unraveling the Art of Riveting with Pop Rivets
Riveting with pop rivets hinges on employing a metal cylinder or tube (the rivet) slightly smaller than the pre-drilled hole's diameter. This rivet passes through the workpieces, whereupon impacts or pressure exerted upon both ends deform the rivet's extremities, thickening the metal column or tube. This simultaneously forms rivet heads or caps, securing the workpieces and thwarting detachment. When external forces strain to separate the workpieces, the rivet's rod and cap withstand the ensuing shear force, a formidable bulwark against separation.
Cold riveting and hot riveting delineate two distinct methods. Cold riveting transpires at ambient temperatures, an efficient process for most riveting scenarios. Hot riveting emerges in contexts demanding heightened connection durability, such as the steel beam riveting in iron bridges. During hot riveting, preheated rivets—glowing red with heat—are inserted into rivet holes, creating rivet heads. The subsequent cooling process contracts the rivets, intensifying the connection's strength.
Simplifying the Complex through Single-Sided Riveting
Historically, riveting necessitated a dual-sided approach. However, the advent of the pop rivet has revolutionized this landscape, ushering in the simplicity of single-sided operation. The pop rivet epitomizes the confluence of innovation and efficiency, fostering ease within the realm of riveting.
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Stamping is a widely used pressure processing method that involves applying pressure to materials at room temperature through a specially designed mould to achieve the desired shape of parts or semi-finished products. The performance of the stamping mould is of utmost importance as it directly influences the accuracy of the workpiece and the efficiency of the stamping process. Let's explore key performance characteristics of a stamping mold.
Wear Resistance: Wear resistance is a fundamental property of the mould material. During the metal stamping process, the material undergoes both flowing and sliding along the mould cavity's surface, leading to significant friction that can cause wear and eventual mould failure.
Hardness: The hardness of the material has a direct impact on the mould's service life and overall quality. A high level of hardness ensures prolonged durability and effective performance of the mould.
Strength and Toughness: To prevent sudden brittle fracture during operation, the mould must exhibit high strength and toughness. Strength indicates the material's ability to resist deformation and fracture, while toughness reflects its resistance to brittle fracture under the influence of strong impact loads.
Fatigue Fracture Properties: Good fatigue resistance is crucial for stamping moulds as they endure repeated loading conditions. Fatigue fractures can occur due to the cyclic stress experienced during the mould's working process.
High-Temperature Performance: Working at elevated temperatures can cause the hardness and strength of the mould material to decrease, resulting in early wear or plastic deformation.
Cold and Thermal Fatigue Resistance: Stamping moulds must demonstrate resistance to cold and thermal fatigue. The repeated heating and cooling cycles can induce tension, pressure, and variable stress, leading to surface cracking, increased friction, and reduced dimensional accuracy.
Corrosion Resistance: Some moulds, like plastic molds, may be exposed to corrosive gases during operation, which can erode the mould cavity's surface, causing wear and failure.
Geometric Parameters: The shape, fit clearance, and fillet radius of the die significantly influence the forming of stamped parts and affect the mould's wear and lifespan.
Good Process Performance: Forging performance and heat treatment performance are vital aspects of process performance. Forging performance refers to how the material behaves during the forging process, while heat treatment significantly affects the quality of the stamping mould, ensuring the desired hardness and wear resistance.
KENENG, as a reliable source manufacturer, can create customised stamping moulds according to your specific needs and carry out mass production. If you require assistance, do not hesitate to reach out to us. We are committed to providing high-quality and cost-effective services and products for all your stamping needs.
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A freeze dryer is a scientific method that pre-freezes water-containing goods before sublimating their moisture in a vacuum state to produce dry items. The freeze-dried items can be preserved for an extended period of time and can be restored to their pre-freeze-drying state while retaining the original biochemical properties after adding water.
Vacuum freeze-drying technique has numerous applications in bioengineering, pharmaceutical industry, food industry, material science, and deep processing of agricultural and byproduct products, and the scale and field are continually developing. To that purpose, vacuum freeze-drying will be a significant application technology in the twenty-first century.
The structure of the Lab freeze dryer
A refrigeration system, a vacuum system, a heating system, and an electrical instrument control system comprise the freeze dryer. The drying box, condenser, refrigeration unit, vacuum pump, heating/cooling device, and so on are the essential components.
The refrigeration system, also known as the "heart of the freeze dryer," is the most critical component of the freeze dryer. Compressor, refrigerant, oil separator, water condenser, filter drier, intercooler, sight glass, solenoid valve, hand valve (top cover valve), expansion valve, evaporation (plate exchanger, rear box condensing coil), vapor-liquid separator, return air filter, pressure gauge, pressure control relay, CPCE (energy regulator), safety valve, refrigeration pipeline, and other components comprise its refrigeration system.
How does Freeze Dryer work?
Freeze drying is a drying process that works on the sublimation concept. It is a method that involves rapidly freezing dry material at a low temperature and then directly sublimating the frozen water molecules into water vapor in a suitable vacuum environment. Freezing The dried product is known as a lyophilizer, and the process is known as lyophilization.
After the liquid refrigerant absorbs the heat of the cooled material in the evaporator, it is vaporized into low-pressure and low-temperature steam, which is inhaled by the compressor, compressed into high-temperature and high-pressure steam, and then discharged into the condenser. It releases heat to the cooling medium (water or air), condenses into a high-pressure liquid, is throttled by a throttling device to a low-pressure and low-temperature liquid, and enters the evaporator again to absorb heat and vaporize.
How do I select a freeze dryer?
Many precise features must be considered while selecting a freeze drier. Customers must purchase a freeze dryer that meets their requirements. When selecting a freeze dryer, examine not only the price, but also the temperature of the cold trap, the cooling rate, the temperature homogeneity of the board, the flatness, and other indicators.
Cold Trap Temperature
A cold trap is a device that traps water during the freeze-drying process. In theory, the lower the temperature of the cold trap, the greater its ability to catch water. The experimental series freeze dryer's cold trap temperature has multiple classes, including -45°C, -60°C, and -80°C. Some items that are easily freeze-dried can benefit from freeze-drying with a cold trap temperature of -45°C. Most items can be freeze-dried using freeze-drying devices with a cold trap temperature of around -60°C. Freeze-drying with a -80°C cold trap temperature It is appropriate for the lyophilization of some specialty items. The influence of cold trap temperature on water-capturing ability was experimentally established, with the water-capturing capacity greatly increased when the temperature of the cold trap dropped from -35°C to -55°C. In the absence of unique requirements, a cold trap temperature of roughly -60 °C is an excellent choice.
Cooling Rate
The cooling rate reflects the refrigeration system's cooling capacity. The temperature of the cold trap shall reach the minimum temperature indicated in the index within 1 hour under no-load conditions. For a freeze dryer with a cold trap temperature of -60 °C, for example, the machine begins timing from the time the machine is turned on for refrigeration, and the time for the cold trap temperature to reach -60 °C should not exceed 1 hour.
Ultimate Vacuum
The final vacuum degree shows the leaking of the freeze drier as well as the vacuum pump's pumping performance. The freeze-drying box's vacuum level. Previously, the higher the vacuum degree, the better. According to contemporary thinking, the vacuum degree should be within a tolerable range. The vacuum degree is too high, which inhibits heat transfer and slows drying, yet the no-load limit vacuum degree of the freeze-drying box should be greater than 15Pa.
Uniformity of plate temperature and flatness
The consistency and flatness of plate temperature have a significant impact on product quality uniformity. The higher the temperature uniformity and flatness, the higher the quality of the freeze-dried product. The temperature of the freeze dryer shelf can be controlled by a heater or an intermediate fluid. The temperature uniformity and flatness of the freeze dryer shelf with an intermediate fluid control layer are excellent. This layer of freeze dryer plate is a hollow sandwich structure. The cooling and heating of the plate are accomplished through the circulation of the intermediate fluid in the fluid channel within the plate, resulting in consistent plate temperature. The fluid in the centre of the shelf technology is used by the freeze dryer. The bell-type freeze dryer's shelf temperature control employs a heater, resulting in slightly poorer temperature uniformity of the plating layer. However, the temperature difference between the layers of the medical freeze dryer should be kept within 1.5 °C, and the temperature difference inside the plate should be kept within 1 °C, and the food freeze dryer can be suitably relaxed.
Summary
We can deduce from the preceding information that different types of laboratory freeze dryers should be used depending on the industry. For many years, DRAWELL has been the most successful freeze dryer producer in China, offering high-quality freeze dryers to laboratories all over the world. Please contact us if your laboratory requires a freeze dryer or other laboratory equipment; we will be your best choice.
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