Listado de la categoría: noticias

While both trituradores de la mandíbula y trituradoras de cono are essential in aggregate and mining operations, they are typically used at different stages and have distinct advantages. Cone crushers generally offer advantages over jaw crushers when used in secondary, tertiary, or quaternary crushing stages, after a primary jaw crusher has already done the initial size reduction.

Key Advantages of Cone Crushers Over Jaw Crushers

Superior Product Shape (Cubicity):

trituradora de cono: Produces a more cubical (equi-dimensional) product. This is due to the combination of compression and attrition as material is crushed between the mantle and bowl liner, and also due to inter-particle crushing when choke-fed. Cubical aggregate is preferred for concrete and asphalt as it provides better strength and workability.

Rompe mandíbulas: Tends to produce more elongated or flaky particles, especially with laminated or slabby feed rock.

Finer and More Consistent Product Size:

trituradora de cono: Can achieve a finer product size and a tighter particle size distribution. They are designed for producing precisely graded materials.

Rompe mandíbulas: Primarily designed for coarse primary crushing, so its product is larger and less uniform.

Mayor rendimiento (in Secondary/Tertiary Stages):

trituradora de cono: For a given physical size (in secondary/tertiary applications), a cone crusher often has a higher throughput capacity than a jaw crusher would if it were forced to produce a similarly sized product. The continuous crushing action contributes to this.

Rompe mandíbulas: Operates with an intermittent crushing action (once per revolution).

Higher Reduction Ratio (in its operating range):

trituradora de cono: Can achieve higher reduction ratios (p.ej., 6:1 a 10:1 or even higher in some modern designs) efficiently when processing pre-crushed material.

Rompe mandíbulas: Typically offers reduction ratios of 3:1 a 5:1 for primary crushing.

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More detailed information about the advantages of cone crusher compared with jaw crusher can be clicked to visit: https://www.yd-crusher.com/a/news/advantages-of-cone-crusher-over-jaw-crusher.html

Instalación de un lining trolley in a tunnel project is a complex and crucial process for the secondary lining of the tunnel. Implica una planificación cuidadosa, adhesión a los protocolos de seguridad, y ejecución precisa.

I. Pre-Installation Planning and Site Preparation

Choose the Installation Location:

Fuera del túnel (privilegiado): Si el espacio permite, ensamble el carrito fuera del portal del túnel. This provides a larger, flatter, and more open area for crane operations, facilitating easier assembly and less constrained working conditions.

Inside the tunnel (si necesario): If outdoor space is limited, the trolley can be assembled inside the tunnel. This requires more precise planning and anchor operations due to confined spaces.

Site dimensions: The installation site should be as flat and wide as possible, typically around 20m x 30m. If installing inside the tunnel, ensure at least 50 cm clearance above the trolley and 30 cm on the sides. The length of the obstacle-free area should be at least twice the length of the trolley plus 3 meters for lifting operations.

Level the Site and Lay the Track:

The ground must be leveled and compacted to create a stable base for the tracks.

Lay the tracks according to the specific gauge requirements of the lining trolley.

Ensure the tracks are straight, free of triangular pits, and have no staggered seams.

Maintain a height difference of less than 5 mm between the front, rear, left, and right rails.

Align the track centerline as closely as possible with the tunnel centerline (error less than 15 mm).

Track sleepers should be spaced generally at 0.5 meters or less and securely nailed.

Use heavy steel rails (p.ej., 38kg/m).

Pre-Operation Inspection & Precauciones de seguridad:

Conduct a thorough inspection of all lining trolley components for any damage, tener puesto, or malfunction.

Ensure all personnel are trained in safety procedures and equipped with appropriate PPE (helmets, guantes, safety harnesses).

Establish clear communication protocols and designated safety zones.

II. Assembly Steps (General Order)

Install the Walking Wheel Frame Assembly:

Use a lifting device (crane or chain block) to place the driving and driven wheel frames onto the laid tracks.

Provide temporary support and adjust the distance between the front and rear wheel frames according to the centerline of the bottom longitudinal beam.

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For more detailed information on the installation of lining trolleys in tunnelling projects visit: https://www.gf-bridge-tunnel.com/a/blog/installation-of-lining-trolleys-in-tunnel-project.html

“Hydraulic inverting bridge formwork” refers to specialized formwork systems used in bridge construction that utilize hydraulic power to manipulate, posición, strip, and advance the formwork. los “inverting” aspect typically means that parts of the formwork (or the entire local form assembly) can be retracted, rotated, or swung away from the cast concrete to allow for easy stripping and movement to the next casting position.The primary types are distinguished by the bridge construction method they support.

Hydraulic Inverting Bridge Formwork Types

Form Travelers (for Segmental Balanced Cantilever Construction):

Descripción: These are complex, mobile steel structures that support the formwork for casting bridge deck segments in place, typically using the balanced cantilever method. A pair of travelers works outwards from each pier.

Hydraulic Role: Hydraulics are extensively used for:

Lifting and lowering the main formwork panels (soffit, side forms, internal forms).

Adjusting the geometry and alignment of the formwork precisely.

“Inverting” or retracting form panels: Side forms often swing outwards or downwards. Soffit forms are lowered. This clears the freshly cast segment.

Advancing the entire traveler assembly along guide rails to the next casting position.

Supporting the weight of the wet concrete and the traveler itself.

Variaciones:

Overhead (Arriba) Form Travelers: The main support trusses are above the deck being cast.

Underslung (Bottom) Form Travelers: The main support trusses are below the deck being cast. The choice depends on pier height, span length, and ground access.

Movable Scaffolding Systems (MSS) / Shoring Gantries (for Span-by-Span Construction):

Descripción: MSS are large, self-launching gantry structures that support the formwork for casting an entire bridge span (or large portions of it) in one go. Once a span is cured, the MSS lowers the formwork and moves itself to the next span.

Hydraulic Role:

Supporting the immense weight of the full span of wet concrete and the formwork.

Lifting and lowering the main support girders of the MSS.

Operating the formwork panels: Similar to form travelers, side forms retract or swing away, and soffit forms are lowered (la “inverting” action) to strip the cast span.

Advancing the entire MSS gantry to the next pier or abutment.

Fine-tuning the alignment and level of the formwork.

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More detailed information about hydraulic inverter bridge formwork types can be found by clicking on visit: https://www.gf-bridge-tunnel.com/a/blog/hydraulic-inverting-bridge-formwork-types.html

The cost of a Fábrica de estructura de acero is influenced by a wide range of factors, encompassing everything from initial design and construction to ongoing operations and market dynamics.

Steel Structure Factory Price Influencing Factors

Diseño e ingeniería:

Complexity of Design: Simple rectangular buildings are cheaper than complex designs with irregular shapes, multiple spans, mezzanines, or specific architectural features.

Building Size and Height: Larger area and greater eave height directly increase material and labor costs.

Requisitos de carga: Heavy loads (p.ej., from overhead cranes, heavy equipment, nieve, viento, actividad sísmica) necessitate stronger, heavier, and thus more expensive steel members and foundations.

Span Length: Longer clear spans (without internal columns) require larger, heavier steel members.

Engineering Fees: Fees for architects, structural engineers, and other consultants.

Building Codes and Standards: Compliance with local, national, and international building codes can influence design complexity and material specifications.

Costos de materiales:

Steel Price: The market price of raw steel is a major variable and can fluctuate significantly.

Type and Grade of Steel: Higher strength steel or specialized alloys (p.ej., for corrosion resistance) are more expensive.

Quantity of Steel: Directly related to the size and design complexity.

Cladding and Roofing Materials: Options range from basic metal sheets to insulated panels, impacting cost and energy efficiency.

puertas, Windows, and Openings: Tipo, tamaño, quantity, y calidad (p.ej., industrial roll-up doors vs. standard personnel doors).

Aislamiento: Type and thickness of insulation for walls and roof.

Fasteners and Connections: Pernos, soldaduras, and other connection materials.

Coatings and Finishes: Paint, galvanizing, or other protective coatings for corrosion resistance and aesthetics.

Costos de fabricación:

Labor Costs: Wages for welders, fitters, operadores de maquinas, etc.

Workshop Overhead: Rent, utilidades, maintenance of fabrication equipment.

Complexity of Fabrication: Intricate cuts, soldaduras, and connections take more time and skill.

Quality Control and Testing: Pruebas no destructivas (NDT) and inspections.

Transportation of Fabricated Members: Distance from fabrication shop to construction site and size/weight of members.

Construction and Erection Costs:

Preparación del sitio:

Land Acquisition: Cost of the land itself.

Geotechnical Survey: To determine soil conditions, impacting foundation design.

Grading and Excavation: Leveling the site.

Foundation Work: Cimentaciones de hormigón (type and size depend on soil and loads) are a significant cost.
Labor Costs for Erection: Skilled erectors, crane operators, riggers.

Equipment Rental: Grúas, man-lifts, scaffolding, etc.

Erection Complexity: Difficult site access, tight working conditions, or complex member assembly can increase time and cost.

Safety Measures and Equipment: Compliance with safety regulations.

Project Management and Supervision: On-site management costs.

Location Factors:

Geographic Location: Labor rates, material availability, and transportation costs vary significantly by region.

Site Accessibility: Easy access for large trucks and cranes reduces costs.

Local Regulations and Permitting: Fees for permits, impact fees, and compliance with local zoning and environmental regulations.

Availability of Utilities: Cost to connect to power, agua, sewer, and gas.

Factory-Specific Requirements (Beyond the Basic Structure):

Overhead Cranes and Hoists: Rails, supporting structures, and the cranes themselves.

Specialized Flooring: Reinforced concrete, epoxy coatings, or specific requirements for machinery.

Egluce (Mecánico, Eléctrico, Plomería): HVAC systems, process piping, electrical distribution for machinery, Encendiendo, fire suppression systems.

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More detailed information about the factors affecting the cost of steel structure factory can be found by visiting: https://www.meichensteel.com/a/news/steel-structure-factory-cost-influencing-factors.html

While steel itself is non-combustible, it loses its structural strength significantly at elevated temperatures (typically around 550°C / 1000°F), which can lead to deformation and collapse during a fire. Por lo tanto, fire prevention and protection measures for steel structures focus on preventing the steel from reaching these critical temperatures or ensuring structural integrity for a sufficient period to allow for evacuation and firefighting.

Steel Structures Prevention Measures

Passive Fire Protection (PFP): Insulating the Steel

The primary goal here is to insulate the steel members to slow down the rate at which their temperature rises during a fire.

Spray-Applied Fire Resistive Materials (SFRM): These are cementitious or gypsum-based plasters sprayed directly onto steel members. They are cost-effective but can be fragile and aesthetically unpleasing if left exposed.

Intumescent Coatings: These paint-like coatings swell and char when exposed to heat, forming an insulating layer. They offer a more aesthetic finish and are often used where steel is exposed.

Concrete Encasement: Encasing steel columns and beams in concrete provides excellent fire resistance. This can be done with cast-in-place concrete or precast concrete sections.

Fire-Resistant Boards and Cladding: Gypsum boards, calcium silicate boards, or mineral wool boards can be used to box in steel members, creating a fire-resistant barrier.

Blockwork/Brickwork Encasement: Similar to concrete encasement, masonry can be built around steel members.

Filling Hollow Sections: Hollow structural sections (HSS) can be filled with concrete or other fire-resistant materials to improve their fire performance.

Active Fire Protection (AFP): Detecting and Suppressing the Fire

These systems aim to detect a fire early and suppress it or control its spread.

Sprinkler Systems: Automatic sprinklers are highly effective in controlling or extinguishing fires, thereby limiting the heat exposure to the steel structure.

Fire Detection and Alarm Systems: Smoke detectors, heat detectors, and flame detectors provide early warning, allowing for timely evacuation and firefighter response.

Fire Suppression Systems (Gaseous, Foam, etc.): Used in specific areas where water might be unsuitable (p.ej., server rooms, areas with flammable liquids).

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