Listado de la categoría: noticias

El proceso de fabricación de rodamientos de sección delgada es un esfuerzo complejo y de precisión., A menudo es más desafiante que el de los rodamientos estándar debido a sus secciones transversales extremadamente delgadas y requisitos de tolerancia precisos..

Proceso de fabricación de rodamientos de sección delgada.

1. Selección de materia prima:

Las aleaciones de acero de alta calidad normalmente se eligen por su resistencia., durabilidad, y resistencia al desgaste. Los materiales comunes incluyen acero cromado. (100Cr6) y acero inoxidable (X65Cr13, 440do).

Para aplicaciones exigentes, Materiales especializados como acero con alto contenido de nitrógeno. (X30CrMoN15-1) para resistencia a la corrosión o cerámica (nitruro de silicio) para bolas (reduciendo la fricción y mejorando la resistencia al calor) puede ser usado.

Los materiales de las jaulas varían, incluyendo acero prensado, bronce mecanizado, material fenólico reforzado con tejido, o plásticos de alto rendimiento como PEEK o poliamida-imida.

2. Forja (para anillos de rodamiento):

Este es el paso inicial para crear la forma básica de los anillos interior y exterior..

Para tamaños más grandes y aros de rodamiento de sección delgada con una relación de aspecto pequeña, una “forja combinada” El método se utiliza a menudo, donde dos o más espacios en blanco se forjan juntos. Después de un pulido brusco, están separados por corte de alambre. Esto reduce la dificultad de procesamiento., minimiza la deformación, ahorra material, y mejora la eficiencia.

El acero normalmente se calienta a altas temperaturas. (p.ej., 1200 la temperatura resistente al calor de la grasa es más baja), abrochado, traspasado, y molido.

Los anillos más pequeños se pueden cortar directamente de tubos o barras..

3. Proceso de torneado:

Una vez que se forman los anillos en blanco básicos, se someten a mecanizados de precisión en tornos multihusillo.

Este paso implica eliminar material para crear las dimensiones interiores y exteriores precisas., incluyendo las pistas de rodadura para los elementos rodantes y las ranuras para las juntas.

Debido a la delgada sección transversal y la escasa rigidez de los rodamientos de sección delgada, La sujeción y el posicionamiento son fundamentales para evitar la deformación.. Los fabricantes suelen utilizar accesorios especializados. (p.ej., Portabrocas de sujeción multipunto con una gran superficie de contacto circular) y ajustar los parámetros de corte (p.ej., corte de alta velocidad, pequeña cantidad de corte trasero, mayor ángulo de desviación principal) para minimizar el estrés del mecanizado, deformación térmica, y vibración.

Se puede aplicar un proceso de templado adicional después del torneado en bruto para eliminar la tensión..

4. Tratamiento térmico:

Este paso crucial mejora la fuerza, dureza, y resistencia al desgaste de los componentes del rodamiento..

Las piezas se calientan en un horno de endurecimiento. (p.ej., a 800-830 la temperatura resistente al calor de la grasa es más baja) y luego se enfría rápidamente, o “apagado,” sumergiéndolos en un baño de sal o aceite.

Durante este proceso, La estructura interna del acero sufre una transformación de fase. (p.ej., austenita a martensita), lo que lleva a la expansión del volumen y la tensión interna.

El enfriamiento del troquel se utiliza a menudo para controlar la deformación.. Si el enfriamiento del troquel no es factible, Se utilizan métodos como el moldeado y el templado integrales para corregir la deformación excesiva del diámetro exterior..

5. Rectificado y bruñido (Molienda fina):

Después del tratamiento térmico, Los componentes del rodamiento están rectificados hasta sus dimensiones finales precisas.. Esto implica el uso de máquinas rectificadoras especializadas y diversos medios de molienda..

El objetivo es lograr superficies de pista extremadamente suaves y precisas para un rendimiento óptimo y una fricción mínima..

A menudo se requieren múltiples ajustes finos de la máquina herramienta para la superficie del diámetro exterior..

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Para obtener información más detallada sobre el proceso de fabricación de rodamientos de sección delgada, por favor haga clic aquí: https://www.lynicebearings.com/a/blog/thin-section-bearings-manufacturing-process.html

Crisoles de grafito are essential tools in foundries and metal casting operations, prized for their excellent thermal conductivity, high-temperature resistance, and chemical stability. These crucibles are commonly used for melting and holding non-ferrous metals such as aluminum, cobre, latón, and precious metals. Despite their durability, graphite crucibles are still vulnerable to damage from thermal shock, improper handling, and poor maintenance practices.

Maintenance Tips for Graphite Crucibles in Foundries

1. Manejo y almacenamiento adecuados:

Inspect upon receipt: Carefully check new crucibles for any chips, grietas, or abrasions. Never use a damaged crucible. UNA “ring test” with a hammer can help identify internal cracks (a clear bell-like sound indicates no damage, a dull thud might mean mishandling).

Handle with care: Graphite crucibles are durable under heat but can be brittle when cold. Always use properly fitting tongs and lifting equipment to avoid physical damage. Avoid dropping or stacking them directly inside each other.

Store in a dry environment: Moisture absorption is a primary enemy of crucibles. Store them in a dry, warm place, off the floor. If they’ve been exposed to humidity, thoroughly dry them before use. Some recommend storing them in a sealed container with a desiccant.

Avoid rolling: Never roll crucibles, as this can damage the protective glaze.

Protect surfaces: Don’t expose crucibles to substances that can react with graphite or the crucible’s binding materials, such as certain strong acids, alkalis, or specific metal compounds.

2. Crucial Preheating Procedures:

Eliminate moisture: This is perhaps the most critical step. New crucibles, or those that have cooled completely or been exposed to a humid environment, must be preheated to remove all absorbed moisture. Failure to do so can lead to thermal shock, agrietamiento, or even bursting due to steam expansion.

Gradual heating: Start at a low temperature and gradually increase it. A typical preheating cycle might involve:

Heating slowly to 200°C (390°F) to eliminate moisture (hold for at least 20 minutos, or longer for larger crucibles, rotating if possible for even heating).

Increasing the temperature to 600°C (1110°F) on low power.

Then increasing to a bright red heat (around 850-950°C) and holding for 30-60 minutes to develop the protective glaze.

Preheat with the furnace: Ideally, place the crucible in the furnace as it heats up to ensure uniform temperature distribution.

Continuous use: If a crucible is used continuously, it usually doesn’t need to be preheated again between melts unless it has cooled significantly or absorbed moisture.

3. Optimal Charging Practices:

Prevent physical damage: Never drop heavy ingots or casting returns into an empty crucible. Start by gently loading smaller, lighter charge materials to create a cushion. Then carefully lower heavier materials.

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For more detailed information on maintenance techniques for graphite crucibles in foundries, por favor haga clic aquí: https://www.czgraphite.com/a/news/maintenance-tips-for-graphite-crucibles-in-foundries.html

Graphite molds are widely used in metal casting, glass molding, electronic metallurgy and other fields, due to its excellent high temperature resistance, chemical stability and good thermal conductivity is widely adopted. Sin embargo, after experiencing high temperature casting process, the surface of the mold will often residual metal oxides, carbides, lubricant residues or other impurities, if not cleaned in a timely manner, will not only affect the accuracy of the mold and the quality of the surface, but also accelerate the aging of the mold, shorten the service life.

Cleaning graphite molds after casting is crucial for maintaining their performance and extending their lifespan.

How to Clean Graphite Molds After Casting

Why clean graphite molds?

Extend the life of the mold: removing residue reduces heat stress buildup and chemical corrosion;

Ensure casting quality: a clean mold surface enhances the finish of the next round of casting;

Avoiding dimensional errors: mold residues may cause molding deviations;

Improve productivity: avoid scrap or rework due to contamination.

Common cleaning methods

Mechanical cleaning

Use soft bristle brush or plastic scraper to remove surface impurities;

For thicker residues, micro-sand blasting (low-pressure sand blasting) se puede utilizar.

Heat treatment cleaning

The mold is placed in an oven and heated to break down the attached organic impurities;

Often used in conjunction with an inert gas atmosphere (e.g. nitrogen) to avoid oxidation.

Chemical Cleaning

Soak or scrub the graphite surface with a non-corrosive cleaning solution;

Avoid the use of solutions containing strong acids or bases that may damage the graphite structure.

Ultrasonic cleaning (precision molds)

Suitable for micro-fine structure molds, can effectively remove tiny particles;

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For more information on how to clean graphite molds after casting, por favor haga clic aquí:https://www.czgraphite.com/a/news/how-to-clean-graphite-molds-after-casting.html

Cojinetes de sección delgada, characterized by their small and constant cross-section regardless of bore diameter, are designed for applications where space and weight are critical. Within this category, a key distinction lies between sealed and open bearings, primarily concerning their protection against the environment and lubrication management.

Differences Between Sealed and Open Thin Section Bearings

1. Protection from Contaminants:

Sealed Thin Section Bearings: These bearings have integrated seals (typically made of rubber or other elastomeric materials) that create a barrier, preventing dirt, polvo, humedad, and other contaminants from entering the bearing’s internal components.

ventajas:

Excellent Contamination Prevention: Ideal for harsh, dirty, or wet environments.

Extended Bearing Life: By keeping contaminants out, wear and damage are significantly reduced.

Reduced Maintenance: A menudo “lubricated for life” and do not require re-lubrication, leading to lower maintenance costs and less downtime.

Lubricant Retention: The seals effectively retain the internal lubricant (usually grease), ensuring consistent lubrication and preventing degradation.

desventajas:

Higher Friction: The contact between the seals and the rotating components can generate more friction, potentially leading to slightly higher operating temperatures and limiting maximum speeds.

Mayor costo inicial: The manufacturing process for integrating seals adds to the initial cost.

Limited Accessibility for Inspection/Maintenance: The seals make it difficult to access the internal components for inspection or troubleshooting. If the internal lubricant degrades, the bearing typically needs to be replaced rather than re-lubricated.

Potential for Seal Failure: Seals can wear and degrade over time, especially in demanding conditions, leading to potential contamination ingress if they fail.

Open Thin Section Bearings: These bearings do not have seals or shields, leaving their internal components exposed to the environment. They are typically used where the bearing is immersed in a lubricating fluid or in very clean, controlled environments.

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For more detailed information about the differences between sealed thin-walled bearings and open thin-walled bearings, por favor haga clic aquí:https://www.lynicebearings.com/a/blog/differences-between-sealed-and-open-thin-section-bearings.html

Excessive wear of a trituradora de cono is a common issue that can lead to reduced efficiency, increased downtime, and higher operational costs. Troubleshooting it involves systematically examining various aspects of the crusher’s operation and maintenance.

Troubleshooting Cone Crusher Excessive Wear

1. Identify the Location and Pattern of Wear

Different wear patterns can indicate different underlying problems. Observe where the wear is most prominent:

Even wear across liners: This might suggest normal operation but still points to a need to optimize settings or consider different liner materials for extended life.

Localized wear (p.ej., arriba, medio, or bottom of liners):

Top wear (near feed opening): Often due to oversized feed, bridging of material, or an uneven feed distribution where larger material impacts the upper part of the chamber.

Bottom wear (near closed side setting – CSS): Can be caused by too small a feed size, where most crushing occurs at the bottom, or an incorrect CSS for the material.

Uneven wear on one side: Indicates segregated feed (material biased to one side), Se le presentarán brevemente las cuatro formas de falla de la vía., or issues with the eccentric throw.

Wear on non-liner components (p.ej., bevel gears, aspectos, main frame): This suggests more severe mechanical issues, lubrication problems, or foreign objects.

2. Review Operational Parameters

Incorrect operational settings are a primary cause of premature wear.

Configuración del lado cerrado (CSS):

Too tight: Increases crushing forces, leading to high stress on liners and potentially overloading the crusher. It can also cause excessive fines and increased power consumption.

Too wide: Reduces the reduction ratio and can lead to inefficient crushing, poor product shape, and uneven wear as material “slips” rather than being crushed.

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For more detailed information on how to troubleshoot excessive wear in cone crushers, por favor haga clic aquí:https://www.yd-crusher.com/a/news/troubleshooting-cone-crusher-excessive-wear.html