Por que é chamado de prato de peixe? A Origem, História e propósito explicados

Quando as pessoas ouvem o termo pela primeira vez “prato de peixe“, uma das perguntas mais comuns é: Por que um componente ferroviário tem o nome de um peixe?

O nome pode parecer incomum porque uma placa de peixe ferroviária não tem nenhuma conexão óbvia com um peixe. É simplesmente um componente de aço instalado nas juntas dos trilhos, usado para conectar e reforçar duas seções de trilho.

No entanto, o nome tem uma história de engenharia muito mais profunda. A palavra “peixe” neste contexto não se refere ao animal. Em vez de, vem de um termo de engenharia mais antigo que descreve uma peça de reforço usada para fortalecer uma junta.

Entender por que é chamado de placa de peixe também ajuda a explicar o importante papel que esse componente desempenha nos sistemas de trilhos ferroviários.

Para engenheiros ferroviários, empreiteiros, e compradores, um prato de peixe não é apenas uma simples barra de aço. É um componente ferroviário fabricado com precisão que afeta diretamente o alinhamento ferroviário, estabilidade articular, e desempenho de pista a longo prazo.

Neste artigo, vamos explicar a origem do nome prato de peixe, como funcionam as placas de peixe ferroviárias, os diferentes tipos disponíveis, e quais fatores devem ser considerados ao selecionar a placa de pesca certa para um projeto ferroviário.

O que é uma placa de pesca ferroviária?

UM prato de peixe ferroviário, também conhecido como barra comum do trilho em algumas regiões, é um componente de fixação de aço usado para unir duas extremidades do trilho.

Durante a instalação, duas placas de peixe são colocadas em ambos os lados da alma do trilho e fixadas usando parafusos de peixe, nozes, e arruelas. Junto, esses componentes criam uma junta mecânica do trilho que mantém as duas seções do trilho alinhadas e estáveis.

Uma montagem conjunta ferroviária típica inclui:

• Seções ferroviárias
• Pratos de peixe
• Parafusos de peixe
• Porcas e arruelas

As principais funções de um prato de peixe incluem:

Mantendo o alinhamento dos trilhos

Uma placa de peixe ajuda a manter as duas extremidades do trilho conectadas na posição correta vertical e horizontalmente, ensuring smooth train operation.

Transferring Wheel Loads

When a train passes over a rail joint, significant impact forces are generated. Fish plates help transfer these forces between adjacent rail sections.

Reducing Rail Movement

Without proper reinforcement, rail joints can experience excessive movement, which may lead to uneven wear, vibração, and track deterioration.

Supporting Maintenance Operations

Unlike welded rail connections, bolted rail joints using fish plates can be installed, inspecionado, and replaced more easily, making them valuable in many railway applications.

Embora o trilho continuamente soldado (CWR) has become common on modern mainline railways, fish plates remain widely used in freight railways, ferrovias industriais, ferrovias de mineração, sistemas ferroviários de guindaste, and maintenance projects.

Por que é chamado de prato de peixe?

The origin of the term comes from historical engineering terminology rather than the appearance of the component.

In older engineering practices, the word “peixe” was used to describe a reinforcing piece fitted alongside a joint to improve its strength and rigidity.

The concept was similar to strengthening a connection by adding additional supporting material on both sides. When railway engineers developed methods for joining rail sections, they adopted this idea and used steel plates to reinforce the rail joint.

Because these plates strengthened the connection between two rails, they became known as pratos de peixe.

Em termos simples:

A fish plate is called a fish plate because it acts as a reinforcing member at a joint, not because it looks like a fish.

This explanation is the most widely accepted origin of the term within railway engineering.

Where Did the Name “Fish” Come From?

The use of the word “peixe” in engineering is older than modern railway systems.

Historicamente, engenheiros usaram o termo para descrever um pedaço de material adicionado para fortalecer ou apoiar outro componente. Uma placa de reforço instalada sobre uma junta era às vezes chamada de “peixe” porque sustentava a ligação da mesma forma que uma peça de reforço em forma de peixe poderia fortalecer uma estrutura.

Quando as primeiras ferrovias se expandiram durante o século 19, os engenheiros precisavam de uma solução prática para conectar seções ferroviárias individuais. Naquela hora, os trilhos foram fabricados em comprimentos limitados, e longos trilhos contínuos não eram práticos.

O desenvolvimento do prato de peixe proporcionou uma solução simples mas eficaz:

• Os trilhos poderiam ser produzidos e transportados em comprimentos gerenciáveis.
• Seções ferroviárias danificadas poderiam ser substituídas mais facilmente.
• A construção de vias tornou-se mais rápida e flexível.
• Rail joints could maintain reasonable strength under train loads.

As railway technology developed, the name remained in use and became a standard term throughout the industry.

Hoje, more than a century later, railway engineers around the world still use the term prato de peixeé.

Does a Fish Plate Actually Look Like a Fish?

This is probably the first question many people ask after hearing the name.

A resposta curta é: not really.

A standard railway fishplate is a relatively simple steel profile designed to match the shape of the rail web. Its design is determined mainly by engineering requirements, incluindo:

• Rail profile compatibility
• Bolt hole arrangement
• Capacidade de carga
• Contact surface area
• Resistência à fadiga

Some historical fishplate designs may have had tapered shapes that loosely resembled the outline of a fish. This may have contributed to the popularity of the name.

No entanto, the engineering explanation is much stronger: the term comes from the idea of reinforcement, not from visual similarity.

Para profissionais ferroviários, the important question is not what the component looks like, but whether it provides a reliable connection between two rails under repeated loading conditions.

Two Names

When purchasing railway components internationally, customers often see two different terms:

• Fish plate
• Joint bar

Are they different products?

Na maioria dos casos, they refer to the same railway component.

The term prato de peixe is widely used in Europe, Ásia, África, and many countries influenced by British railway terminology.

The term barra conjunta is more commonly used in North America, especially in railway standards and specifications related to American Railway Engineering and Maintenance-of-Way Association.

Although the names are different, the function is the same:

A steel component installed on both sides of a rail joint to connect two rail sections and maintain track stability.

When sourcing fish plates internationally, engineers should focus less on the terminology and more on technical specifications, incluindo:

• Perfil ferroviário
• Hole spacing
• Material grade
• Propriedades mecânicas
• Padrão ferroviário aplicável

A fish plate manufactured for one rail profile may not be suitable for another, even if the overall appearance looks similar.

How Does It Work?

A fishplate may look like a simple steel component, but its role in a railway track system is critical.

A rail joint is one of the areas where a track structure experiences concentrated stress. When a train passes over the joint, the wheel load creates vertical impact forces, while braking, aceleração, and lateral movement generate additional stresses.

The purpose of a fish plate is to reinforce this connection and help the two rail sections behave as closely as possible like one continuous rail.

A typical fish plate connection works through several key elements:

Supporting the Rail Web

Fishplates are installed on both sides of the rail web. The contact between the fish plate and the rail provides additional support around the joint area, increasing the overall stiffness of the connection.

Securing the Rail Joint with Fish Bolts

Fish bolts pass through the rail and fish plates, clamping the assembly together.

The correct bolt size, hole position, and tightening force are important because insufficient clamping can lead to:

• Rail movement
• Bolt loosening
• Increased impact at the joint
• Accelerated wear

Maintaining Track Geometry

A properly designed fishplate helps maintain:

• Alinhamento ferroviário
• Rail level
• Track gauge
• Joint stability

This is especially important in areas where trains operate under heavy axle loads or frequent traffic conditions.

Do ponto de vista da fabricação, dimensional accuracy is essential. The bolt hole position, machining tolerance, and contact surface must match the rail profile precisely to ensure proper installation.

Main Types

Railway fishplates are not one universal product. Different railway systems require different designs depending on rail profiles, condições de operação, e padrões.

The most common types include the following.

Padrão

Standard fishplates are designed to connect two identical rail sections.

They are commonly used in conventional railway tracks where the same rail profile is installed throughout the line.

Exemplos incluem:

• UIC54 fish plates
• UIC60 fish plates
• 115RE fish plates
• 136RE fish plates

The design must match the exact rail profile to ensure correct contact and load transfer.

Compromise

A compromise fish plate is used when two different rail profiles need to be connected.

Por exemplo, a railway may need to transition from one rail size to another due to:

• Track renewal projects
• Different sections of existing railway
• Connection between old and new rail systems

Because different rail profiles have different heights and web shapes, standard fish plates cannot be used. A specially designed compromise fish plate provides a smooth and secure transition.

Insulated

Insulated fishplates are designed for railway signaling systems.

In many railway networks, the rails are also used as part of electrical track circuits. To detect train positions, adjacent rail sections must sometimes be electrically separated.

Insulated fish plates include insulating components that prevent electrical continuity between rail sections while maintaining mechanical strength.

They are commonly used in:

• Signaling sections
• Railway control systems
• Passenger railway networks

Trilho do guindaste

Crane rail fishplates are designed for industrial rail applications, especially where rails are installed for overhead cranes or heavy material handling equipment.

Compared with standard railway tracks, crane rail systems often experience:

• High wheel loads
• Frequent starting and stopping
• Concentrated contact stress

Portanto, crane rail fish plates require suitable design and material selection to provide long-term durability.

As aplicações típicas incluem:

• Steel plants
• Ports
• Shipyards
• Manufacturing facilities

Heavy-Duty

Heavy-duty fish plates are developed for demanding railway environments where high axle loads and intensive traffic are expected.

They are commonly used in:

• Ferrovias de mineração
• Ferrovias de carga pesada
• Industrial transportation systems

These applications require higher strength materials and strict quality control because the rail joint experiences repeated dynamic loading.

What Materials？

Because fishplates are exposed to repeated impact forces, vibração, and environmental conditions, material selection plays an important role in their performance.

Most railway fish plates are manufactured from high-strength carbon steel or alloy steel.

Common material requirements include:

• High tensile strength
• Good fatigue resistance
• Adequate toughness
• Resistência ao desgaste
• Stable performance under repeated loading

Depending on customer requirements and railway standards, fish plates may be manufactured according to:

• Padrões UIC
• Especificações AREMA
• Padrões BS
• Padrões DIN
• Padrões GB
• Especificações específicas do cliente

Tratamento Térmico e Propriedades Mecânicas

Para aplicações ferroviárias exigentes, a seleção de materiais por si só não é suficiente.

O tratamento térmico é frequentemente necessário para melhorar as propriedades mecânicas do prato de peixe.

Um processo de tratamento térmico adequadamente controlado pode melhorar:

Força

A placa de peixe deve suportar cargas repetidas de trens que passam sem deformação permanente.

Resistência à fadiga

As juntas ferroviárias passam por milhões de ciclos de carregamento durante o serviço. Um bom desempenho à fadiga ajuda a prevenir fissuras e falhas prematuras.

Desempenho de desgaste

A área de contato ao redor da junta do trilho está exposta a vibrações e impactos. As propriedades aprimoradas do material contribuem para uma vida útil mais longa.

Por esta razão, professional railway component manufacturers pay close attention to both material quality and production processes.

Are Fish Plates Still Used on Modern Railways?

With the widespread adoption of continuously welded rail (CWR), some people believe that fish plates are becoming outdated.

No entanto, this is not the case.

Although CWR has reduced the number of traditional rail joints on many main railway lines, fish plates remain an important component in many railway applications.

They are still widely used in:

Railway Maintenance

During rail replacement or repair work, temporary and permanent rail connections often require fish plates.

Turnouts and Special Trackwork

Railway switches and crossings involve complex rail arrangements where bolted connections may still be required.

Industrial Railways

Factories, portos, minas, and warehouses often use rail systems where flexibility and maintenance convenience are important.

Crane Rail Systems

Industrial crane rails frequently rely on bolted joints because of their operating environment and maintenance requirements.

Regional and Conventional Railways

Many railway networks around the world continue to use traditional rail joint systems due to infrastructure conditions and operational requirements.

Why Fishplates Remain Important Despite Modern Welding Technology

Continuously welded rail provides many advantages, incluindo:

• Reduced rail joint impact
• Smoother train operation
• Lower maintenance requirements

No entanto, welded rail is not always the best solution for every situation.

Fish plates still provide several practical advantages:

Easier Installation

Bolted rail joints can be installed without specialized welding equipment.

Easier Replacement

Damaged rail sections can be removed and replaced more efficiently.

Greater Flexibility

Certain railway applications require removable or adjustable connections.

Suitable for Special Applications

Ferrovias industriais, crane rails, and temporary tracks often require solutions where fish plates remain the most practical choice.

Do ponto de vista da engenharia, fish plates and welded rail systems are not competitors. They are solutions designed for different railway requirements.

Fish Plate vs. Welded Rail Joints: Which One Is Better?

When discussing modern railway construction, one common question is whether fish plates are still necessary when welded rail technology is widely available.

The answer depends on the railway application.

Both fishplate joints and welded rail joints have their own advantages, e os engenheiros selecionam a solução mais adequada com base nas condições operacionais, requisitos de manutenção, e especificações do projeto.

Para ferrovias de passageiros de alta velocidade, trilho continuamente soldado é geralmente preferido porque fornece condições de funcionamento mais suaves.

No entanto, para muitas aplicações ferroviárias industriais e convencionais, pratos de peixe continuam a ser uma solução confiável e prática.

Um engenheiro ferroviário profissional não escolhe simplesmente a tecnologia mais recente. A escolha correta depende do ambiente operacional real.

How to Choose the Right Railway Parts?

Selecting a fish plate requires more than choosing a component that looks similar.

A railway fishplate must match the rail profile, fastening system, and operating requirements of the track.

The following factors should be considered before production or purchase.

1. Compatibilidade de perfil ferroviário

The first and most important factor is the rail profile.

Different rails have different:

• Rail head dimensions
• Espessura da teia
• Rail height
• Largura do pé
• Bolt hole positions

Por exemplo, a fish plate designed for UIC60 rail cannot simply be installed on a UIC54 rail.

Common rail profiles include:

• UIC54
• UIC60
• 115RÉ
• 132RÉ
• 136RÉ
• 60E1
• 50kg/m rail
• Crane rail profiles

The fishplate must be designed according to the exact rail section.

2. Applicable Railway Standard

Different countries and railway systems may follow different technical standards.

Common standards include:

• UIC
• AREMA
• Bobagem
• DE
• GB

Before manufacturing, os clientes devem confirmar:

• Padrão exigido
• Especificações de desenho
• Requisitos de materiais
• Critérios de inspeção

Isso garante que a placa de pesca atenda às expectativas do projeto ferroviário.

3. Grau do material e desempenho mecânico

O material deve corresponder às condições de operação.

Para aplicações de carga pesada, engenheiros geralmente se concentram em:

• Resistência à tracção
• Força de rendimento
• Dureza
• Resistência à fadiga

Um prato de peixe usado em uma ferrovia de mineração, por exemplo, pode exigir desempenho superior ao usado em uma pista industrial leve.

4. Projeto de furo de parafuso

A disposição dos furos dos parafusos é outro fator crítico.

Parâmetros importantes incluem:

• Número de furos
• Diâmetro do furo
• Hole spacing
• Posição do furo
• Especificação do parafuso

Dimensões incorretas do furo podem impedir a instalação adequada e reduzir o desempenho da junta.

5. Ambiente Operacional

O ambiente de trabalho também influencia a seleção do prato de peixe.

Fatores incluem:

• Carga por eixo
• Velocidade do trem
• Frequência de tráfego
• Mudanças de temperatura
• Condições de umidade e corrosão

A fishplate used in a heavy-haul railway requires a different design approach compared with one used in a light industrial railway.

Why Quality Manufacturing Matters for Railway Fish Plates

Although bar joint is much smaller than a rail or sleeper, it plays a critical role in railway safety and reliability.

A rail joint is one of the areas where the track structure experiences concentrated stress. Poor-quality fish plates may result in:

• Incorrect rail alignment
• Bolt loosening
• Increased impact forces
• Faster component wear
• Shortened service life

Por esta razão, professional railway component manufacturers focus on every stage of production.

Important quality control steps include:

Material Inspection

Steel materials should be checked to ensure they meet the required chemical composition and mechanical properties.

Usinagem de Precisão

Accurate dimensions are essential for proper fitting with the rail profile.

Hole Position Inspection

Bolt holes must maintain strict tolerances to ensure correct assembly.

Controle de Tratamento Térmico

Where required, heat treatment must provide stable mechanical performance.

Inspeção Final

Finished fish plates should be inspected according to project requirements before shipment.

From our manufacturing experience, one of the most common mistakes in railway component purchasing is selecting a fish plate based only on appearance or price.

A reliable fishplate must be matched with the rail system it is designed for.

Railway Fishplate Manufacturer

No Luoyang Fonyo Indústrias Pesadas Co., Ltda., we manufacture railway fish plates and other railway track components for customers in railway, industrial, mineração, and material handling applications.

Our railway fish plates are produced according to international standards and customer-specific requirements, incluindo:

• Padrões UIC
• Especificações AREMA
• Padrões BS
• Padrões DIN
• Padrões GB

We focus on providing reliable railway components through:

• Suitable material selection
• Precision manufacturing
• Strict dimensional inspection
• Professional technical support

In addition to railway fish plates, our product range includes:

• Railway fish bolts
• Clipes ferroviários
• Clipes de trilho elásticos
• Almofadas ferroviárias
• Railway sleepers
• Other railway fastening components

By supplying compatible railway components from one source, we help customers simplify procurement and ensure better system compatibility.

Whether you need standard railway fish plates or customized solutions based on drawings and technical specifications, Luoyang Fonyo Indústrias Pesadas Co., Ltda. can provide professional support for your railway project.

Perguntas frequentes

1. Why is it called a fishplate?

The name comes from an old engineering term. “Fish” referred to a reinforcing member used to strengthen a joint. A railway fish plate reinforces the connection between two rail sections, which is why it received this name.

2. Is a fish plate the same as a joint bar?

Sim. In most railway applications, fishplate and joint bar refer to the same component. “Fish plate” is commonly used in many international markets, enquanto “barra conjunta” is frequently used in North American railway terminology.

3. What is the purpose of a railway fish plate?

A fish plate connects two rail sections, maintains alignment, transfers wheel loads, and reinforces the rail joint to improve track stability.

4. Are fish plates still used on modern railways?

Sim. Although continuously welded rail is common on many high-speed railways, fish plates are still widely used in industrial railways, maintenance work, crane rails, comparecimentos, and conventional railway systems.

5. What materials are railway fish plates made from?

Most fishplates are manufactured from high-strength carbon steel or alloy steel. Material selection depends on the railway standard and operating conditions.

6. Can one fish plate fit different rail profiles?

Não. Fishplates are designed according to specific rail profiles. Different rails require matching fish plate dimensions and bolt arrangements.

7. What information is needed to manufacture a custom fish plates?

Manufacturers usually need:

• Perfil ferroviário
• Drawing or specification
• Padrão ferroviário
• Material requirement
• Bolt hole details
• Quantity requirement

8. How long can a fish plate last?

The service life depends on factors such as axle load, traffic frequency, qualidade de instalação, manutenção, and operating environment.