The plastic crusher is a crucial piece of equipment for the recycling industry, as it is designed to break down solid plastic waste efficiently for further processing. By crushing the plastic materials into smaller pieces, they can be easily and safely recycled, reducing environmental hazards and waste buildup. With a growing emphasis on sustainability and recycling, investing in a suitable plastic crusher is essential for businesses dealing with large volumes of plastic waste.

Selecting the appropriate plastic crusher requires consideration of various factors, such as the methods of feeding and collecting materials, capacity, material composition, and output size. These factors dictate the effectiveness of the machine’s crushing and recycling process, ensuring productivity and reduced waste. By understanding the importance and function of a plastic crusher, industries can make informed decisions that maximally benefit their waste management and recycling programs.

Understanding Plastic Crushers

Types of Plastic Crushers

There are several types of plastic crushers designed for specific materials or applications. Some common types include:

  • PP Crusher: Ideal for crushing polypropylene (PP) materials, commonly found in packaging, such as plastic bags and containers.
  • PE Crusher: Designed for polyethylene (PE) material, which is widely used in product packaging and various household items.
  • PET Crusher: Suitable for handling polyethylene terephthalate (PET) materials, which are primarily used in plastic bottles for beverages and other liquids.
  • PA (Nylon) Crusher: Developed for crushing polyamide (PA) materials, more commonly known as nylon, which is commonly used in textiles and engineering thermoplastics.

Each type of crusher is tailored to handle the specific characteristics of the targeted plastic material, ensuring efficient processing and reducing the risk of damage to the machine.

Main Components and Structure

Plastic crushers typically consist of several main components and a specific structure to facilitate the crushing process. Some key components include:

  1. Hopper: The top-loading chamber where the plastic waste is fed into the machine.
  2. Crushing Chamber: The area where the plastic materials are broken down into smaller granules by cutting or grinding.
  3. Fixed and Rotating Blades: The primary tools responsible for cutting and grinding the plastic materials in the crushing chamber.
  4. Screen: A perforated or meshed panel that separates the granulated materials by size, allowing for uniform output.
  5. Collection System: The system that collects and transports the crushed plastic granules to the desired output location.

The structure of a plastic crusher varies depending on the specific machine and application, but generally consists of a sturdy, durable frame designed to withstand the force and vibrations generated during operation. The crushing chamber is often equipped with multiple fixed and rotating blades, which work together to break down the plastic materials into the desired granular size.

A key factor in the success of the plastic crusher is its ability to precisely control the size of the output. To achieve this, many machines employ a <a href=””>granulator</a>, which not only facilitates the initial breaking down of the plastic but additionally ensures consistent granule size for effective plastic waste management and recycling.

In summary, understanding how plastic crushers function and their various types and components is essential to efficiently process and recycle plastic waste materials. By selecting the appropriate type of crusher based on the specific plastic material and application, waste management and recycling professionals can maximize their plastic recycling efficiency and achieve effective waste management practice.

Material Handling and Feeding

Manual Feed

Manual feeding involves physically handling and introducing plastic waste materials into the plastic crusher. This method requires operators to use tools such as shovels, forklifts, or buckets to transfer materials from a collection point to the crusher. Despite being labor-intensive, manual feeding allows for better control over the amount and type of materials being loaded into the machine, minimizing the risk of machine jams and damage.

Infeed Materials

Different types of plastic materials may require different conveyor systems to efficiently handle and feed them into the plastic crusher. Examples of infeed materials include purgings, sprue, gates, and reject parts. It is crucial for the success of the crushing process to select the proper conveyor system for the type of material being processed. This can include:

  • Belt conveyors: Suitable for a wide range of materials, adjustable and easy-to-clean
  • Screw conveyors: Ideal for granular materials and those with varying particle sizes
  • Pneumatic conveyors: Useful for conveying lightweight materials and when space is limited

These conveyor systems efficiently transport the waste plastic materials to the crusher, reducing manual labor and ensuring a consistent and seamless crushing process.

Metal-Inclusive Materials

Handling plastic waste materials that may contain metal components can pose challenges for plastic crushers. Metal contaminants within the plastic can damage the crusher’s blades, reduce efficiency, and potentially cause equipment failure. To address this issue, it is recommended to implement metal detection and separation systems, such as magnetic separators, to remove any metal components before the materials are fed into the crusher. This helps to safeguard the crusher from potential damage and maintain optimal performance.

Overall, proper material handling and feeding are essential for the success of the plastic crushing process. Operators must ensure that the correct equipment, such as conveyors and metal separators, is in place and that proper procedures are followed when handling, transporting, and feeding plastic waste materials into the crusher.

Crushing Process

Primary Size Reduction

The primary size reduction in a plastic crusher starts with the feeding of the plastic waste materials into the machine. This stage focuses on breaking the waste plastic into smaller pieces called lumps. The size of these lumps depends on the type of plastic and the crusher’s working capacity. The process involves an electrically driven rotor equipped with crusher blades that cut and shear the plastic materials, turning them into smaller pieces. These blades are strategically positioned on the rotor to maximize the efficiency of the cutting process1.

To ensure even distribution of the plastic waste, it is essential to keep the crusher feeding consistently and avoid overloading. This approach not only maintains the desired lump size but also prevents the machine from getting clogged or damaged due to excessive pressure2.

Secondary Size Reduction

Once the plastic materials have undergone primary size reduction, they are then subjected to secondary size reduction to achieve the desired output size. This process typically employs a screen with specific opening sizes placed at the bottom of the crusher chamber. The crushed plastic particles pass through these openings, effectively controlling the size of the final product3.

During secondary size reduction, it is vital to pay attention to the various factors affecting the process’s efficiency. These factors include:

  • Rotor speed: A higher rotor speed can potentially generate smaller particles, but it may also lead to increased wear and tear in the machine
  • Blade sharpness: Dull blades may reduce the overall efficiency of the cutting and shearing process, leading to larger lumps being produced
  • Screen opening size: Having the appropriate screen size determines the size of the output plastic particles, as well as the smoothness of the crushing process4

It is crucial to monitor and maintain these factors to achieve the best possible secondary size reduction and ensure that the plastic crusher operates at peak efficiency. Remember to take into account relevant considerations such as rotor speed, blade condition, and screen size to yield a homogeneous output size for the crushed plastic materials.


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Plastic Materials and Types

Pure Plastic

Pure plastics are commonly used as primary materials for plastic crushers. Some examples of these plastics include polyethylene (PE), polypropylene (PP), and polystyrene (PS). These materials are suitable for plastic crushers because of their soft and pliable characteristics. They are also often found in a variety of everyday items, making them a prevalent source of waste plastic material for recycling and reusing.


Raffia is a type of plastic made from woven materials, which is different from more traditional solid plastic. It cannot be directly processed by a standard plastic crusher, as it decreases the machine’s output due to its entangled nature during processing. Specialized equipment, like shredders, is often required for handling this type of material.


Plastic film, which includes materials like plastic bags or shrink wrap, is another kind of waste material that is not typically processed by plastic crushers. These films need to be handled separate from other types of plastics, as they tend to wrap around or bridge the crusher’s parts, resulting in decreased output and operational difficulties. Alternative recycling methods may be necessary for managing plastic film waste.

Hard Plastics

While most plastics can be crushed by standard plastic crushers, some hard plastics like nylon (PA) may be too difficult to process. These materials require a special rotor for effective crushing. However, it is important to note that hard plastics are less common than other types of plastic materials in the recycling process.


Different types of plastic materials have unique properties and require different recycling methods. In general, pure plastic materials are easiest to process by plastic crushers, while raffia and film materials need specialized equipment or alternative recycling methods. For the rare instances of hard plastic material waste, specialized rotors are needed for effective crushing.

Noise and Vibration Control

In plastic crushers, noise and vibration are two factors that can impact both the efficiency of the machine and the operator’s well-being. To ensure a safe and productive working environment, it is vital to minimize the noise and vibration levels associated with these machines.

One approach to reduce noise in plastic crushers is using a soundproof cover. A soundproof cover can effectively block and absorb a significant portion of the emitted noise, making the crusher quieter and more tolerable for operators and nearby workers. Installing a soundproof cover is usually a straightforward and cost-effective option for mitigating noise levels in plastic crusher operations 1.

Another technique for controlling noise is by replacing the old or worn-out cutters. An old cutter could generate higher levels of noise due to irregularities and misalignments that develop over time, leading to increased vibrations. Ensuring the cutters are in good condition and replaced when necessary not only helps in controlling noise but also maintains the efficiency and longevity of the crusher1.

Vibration control is also crucial in plastic crusher operations. Excessive vibrations can lead to several problems, including increased wear and tear of machine components, reduced operator comfort, and potential safety hazards. Implementing vibration isolation measures, such as utilizing rubber mounts or anti-vibration pads, can help minimize vibrations transmitted through the machine’s structure to the surrounding environment2.

In summary, noise and vibration control in plastic crushers involves the use of soundproof covers, regular maintenance and replacement of cutters, and implementing vibration isolation measures. Taking these actions can not only create a more comfortable and safe working environment but can also contribute to the overall performance and longevity of the equipment.

Capacity and Model Selection

When choosing the right plastic crusher, it is crucial to consider the capacity and model selection. Capacity refers to the amount of material that the crusher can process within a given time, while model selection is determined by various factors, including the ways of feeding and collecting materials, material composition, and the desired output size.

The capacity of a plastic crusher is directly related to the machine’s size, motor power, and other factors. For example, a larger crusher with a more powerful motor can usually process a higher volume of plastic in a shorter period. To determine the correct capacity for your specific application, you should first assess the weight or volume of plastic materials you will be processing daily or hourly. It is essential to choose a model with the appropriate capacity to provide efficient and consistent results.

Model selection is also critical when choosing a plastic crusher, as it influences the overall efficiency, safety, and other aspects of the machine. Some factors to consider during model selection include:

  1. Material composition: Different plastic materials have varying properties, which can affect the crushing process. For instance, brittle plastics require less force to break, while flexible materials might need a more robust machine. Make sure to select a crusher designed to handle your specific type of plastic.
  2. Ways of feeding and collecting materials: Consider how the materials will be fed into the crusher and how the crushed plastic will be collected. Some crushers use conveyor belts or other automatic feeding systems, while others rely on manual input. Likewise, crushed materials can be discharged directly into a storage container or onto a conveyor for additional processing. Choose a model that best fits your production needs.
  3. Output size: The size of the crushed plastic materials will affect their usability in various applications. Ensure the crusher you select allows for the adjustment of the output size to meet the requirements of your specific purpose. Some crushers allow for easy size adjustments,<a href=””> allowing users to change sieving screens as needed</a>.

In summary, selecting the appropriate capacity and model for a plastic crusher is essential for efficient operation and optimized results. Consider factors such as material composition, feeding and collecting methods, and output sizes to ensure you choose the best machine for your plastic recycling needs.

Motor and Power Consumption

Plastic crushers play a crucial role in waste management and recycling applications. The motor and power consumption of a plastic crusher influence its efficiency, cost-effectiveness, and overall performance. This section examines the factors that contribute to an ideal motor and power consumption for plastic crushers.

Motor Selection

The motor is a critical component of a plastic crusher, as it directly impacts the machine’s crushing capabilities. A well-chosen motor should be able to deliver sufficient power to perform the required tasks effectively. When selecting a motor, consider factors like dynamic balancing, drive belts, and bearing, which contribute to the overall crushing efficiency (source). Wiscon Envirotech, for example, uses a second-grade power-efficient motor designed to save on energy consumption.

Medium speed electric motors are common in a plastic crusher, such as the 3-phase 10Hp motor used in a particular setup mentioned in a study. The motor type and size should match the crusher’s size and requirements; for instance, a medium-sized crusher can crush up to half a ton of plastic per day.

Power Consumption

Efficient use of power is essential when operating a plastic crusher. Factors like the crusher’s size, design, and motor help govern its overall power consumption. A well-designed plastic crusher should occupy minimal space, consume low amounts of power, and be easy to maintain (source).

Plastic crushers may come in various sizes and capacities, which affects their power consumption. A crusher with a rotor length between 300 and 1500 mm can produce 400 kg/hr to 1500 kg/hr, depending on the customer’s specifications (source). Selecting a plastic crusher with an appropriate motor size and rotor length is essential to optimize power consumption and performance.

In conclusion, the motor and power consumption play a critical role in the efficiency and success of a plastic crusher. When selecting a plastic crusher, it’s important to consider factors like motor size, power efficiency, and design to ensure optimal performance and minimal energy waste.

Machine Maintenance and Inspection

When it comes to the maintenance and inspection of plastic crushers, it is crucial to follow a proper schedule to avoid any undue damage or inefficiency in the machine’s performance. Proper maintenance methods, such as regular checkups, and lubrication should be applied. In this section, we will discuss the essential aspects of this process, focusing on maintenance, inspection, and the simplicity of maintenance.

One of the key factors in maintaining the efficiency of a plastic crusher is ensuring the sharpness of its blades. The blades play a vital role in the machine, and if they are damaged or dull, the performance will be negatively affected. As a result, it is important to regularly check the blades and maintain their sharpness to keep the crusher functioning well.

It is also important to follow a regular maintenance schedule for the hydraulic power units, as outlined by Metso Outotec. This includes daily checks on the following aspects:

  • Condition and cleanliness of the hydraulic power units
  • Hydraulic oil tank levels
  • Oil temperatures
  • Cooling fans
  • Oil pressure levels

In addition to the daily checks, there should be regular inspections of safety devices and oil analysis. Failure to comply with such regular inspection can lead to the malfunctioning of safety devices and reduction in the overall performance of the crusher.

Another aspect of maintenance to consider is the frequency of changing the oil in the plastic crusher. According to Thomasnet, it is recommended to change the oil at least once per year or every 2,000 hours. This helps prevent any issues related to oil degradation and ensure the long-term operation of the machine.

Lastly, it is essential to consider the simplicity of maintenance when it comes to plastic crusher machines. A crusher with easy-to-access components simplifies the maintenance process and minimizes the need for specialized tools or expertise. This factor can significantly reduce the downtime and operational costs associated with maintenance procedures.

In conclusion, proper machine maintenance and inspection play a vital role in the efficiency and longevity of plastic crushers. Following these guidelines can help ensure the maximum performance and usability of the plastic crusher.

Safety Guidelines and Procedures

Water Sprinkler System

In plastic crushing operations, a water sprinkler system is essential for keeping the work area safe from potential hazards like fire and dust. The system ensures that enough water is applied to the workspace to minimize risks while not adversely affecting the plastic crusher’s overall efficiency.

Installing a properly sized water sprinkler system prevents any plastic particles from accumulating on equipment surfaces and reduces the risk of fires caused by friction. It also prevents harmful dust from spreading around the workspace, ensuring a clean and healthy working environment for employees.

Overload Prevention

An efficient plastic crusher should be equipped with a reliable overload prevention system to protect the machine from potential damage. This entails the following safeguards:

  • Ensure that each part of the motor, speed reducer, hydraulic coupling, head, and machine are complete, intact, and fastened securely 1.
  • Regularly examine the equipment and follow the lock-out, tag-out, try-out (LOTOTO) procedures when performing maintenance, repairs, or adjustments to maintain crusher safety and efficiency 2.
  • Train operators in recognizing signs of potential overload, such as excessive noise or unusual vibrations, and report them promptly to prevent accidents or equipment failure.

Safety Tips

When working with plastic crusher machines, it is crucial to follow safety procedures, including:

  • Always keep hands away from the moving parts of the machine, especially during operation 3.
  • Wear proper safety gear, such as safety glasses, gloves, and hearing protection, to minimize risks of injury.
  • Follow manufacturer instructions and safety warnings for maintenance procedures 4.

By implementing these safety guidelines and procedures, a plastic crusher’s lifespan can be extended, while simultaneously ensuring the safety and well-being of its operators.


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Additional Features and Considerations

Bearing and Knife Material

When selecting a plastic crusher, it’s important to consider the materials used in the construction of the bearings and knives. These components play a crucial role in ensuring the machine operates efficiently and has a long service life. Bearings should be designed to withstand heavy load and remain stable during operation. It’s common to use high-quality stainless steel or other durable, non-corrosive materials in the construction of the bearings.

In terms of knife material, it’s essential to choose blades made from materials that are both durable and resistant to corrosion and abrasion. Nitriding steel is a popular choice for crusher blades as it offers long-lasting performance and is easy to maintain ^4^. This is particularly important when processing materials that may be abrasive or corrosive, such as wood or certain types of plastic.

Dimension and Transport

Another important aspect to consider when selecting a plastic crusher is its size and weight. A machine that is too large or heavy may be difficult to transport or install in your facility. On the other hand, a crusher that is too small may not have the capacity to handle your plastic waste needs. Be sure to select a model with dimensions and weight that are suitable for your workspace and processing requirements.

Additionally, consider the power requirements of the machine, as this can impact installation and operation costs. A crusher with a lower power consumption will typically be more cost-effective in the long run.

Material Composition

Understanding the types of plastic materials that will be processed by the crusher is crucial when selecting a machine. Different plastics have varying densities and characteristics, so it’s important to choose a crusher that can handle the specific materials you plan to recycle. For example, the efficiency of crushing based on polymers processed differ, with 90% for HDPE, 68% for LDPE, 45% for PVC, and 10% for PET bottles ^3^.

By considering these additional features and selection criteria, you can more effectively choose a plastic crusher that meets your specific needs and helps streamline your recycling operations.

Post-Crushing Process

The post-crushing process involves several steps to ensure that the plastic is properly pulverized and separated from any unwanted materials. In this section, we will discuss Cyclone Collection and Powder Handling as well as the Rejection of Unwanted Materials.

Cyclone Collection and Powder Handling

Once the plastic materials have been crushed, they need to be separated from impurities such as metal or other solid contaminants. This is where a cyclone collection system comes into play. Cyclone collection utilizes centrifugal force to separate particles based on their size, density, and shape, allowing the plastic powder to be efficiently collected while heavier contaminants are separated and discarded.

After the cyclone collection process, the pulverized plastic powder needs to be handled and stored appropriately. The following measures should be taken to ensure safe and efficient powder handling:

  • Transportation: Utilize pneumatic conveyor systems or vacuum conveyors to transport the plastic powder from the cyclone collector to the designated storage area.
  • Storage: Store the plastic powder in sealed, air-tight containers or silos to minimize exposure to moisture and prevent contamination.
  • Cleaning: Regularly clean and sanitize the cyclone collector and the conveying system to ensure hygienic and efficient operations.

Rejection of Unwanted Materials

Despite the efficiency of the crushing and cyclone collection processes, there might still be unwanted materials, such as metal, that make their way into the final plastic powder product. To minimize the presence of these contaminants, rejection systems are employed. These may include:

  • Magnetic Separation: This method uses powerful magnets to remove ferrous metals from the plastic powder. A magnetic separator is typically installed within the conveyor system to attract and separate metal particles from the pulverized plastic.
  • Optical Sorting: In this technique, an optical sorter uses cameras, sensors, and advanced algorithms to detect and separate various types of contaminants based on their color, shape, size, or composition. This can be particularly useful for removing different types of plastics and other non-metallic contaminants.
  • Air Classification: Air classifiers use a combination of airflow and gravity to separate unwanted materials from the plastic powder based on differences in particle size, density, and shape. This can help to further refine the plastic powder and improve its quality.

By implementing these strategies in the post-crushing process, it is possible to effectively separate and handle the pulverized plastic, ensuring a high-quality and safe final product for recycling and reuse purposes. Remember that regular maintenance and cleaning of the equipment involved in the process are essential to achieving optimal results.

Detecting and Handling Metal Contamination

Detecting and handling metal contamination in plastic materials is an essential step in the recycling and manufacturing process. In order to ensure product quality and safety, various techniques are employed to identify and remove any metal contaminants that may be present.

One of the most common methods for detecting metal contamination in plastics is using a metal detector. These devices can efficiently identify metals such as steel, aluminum, or copper within plastic materials. Metal detectors, like those developed by Sesotec, are specifically designed for the plastics industry to ensure the purity of the product and prevent any quality issues or equipment blockages.

There are different types of metal detectors available, including:

  • Conveyor belt metal detectors, which are placed directly on the production line and scan product in motion.
  • Gravity feed metal detectors, used with materials that flow through a pipe after being granulated or shredded.
  • Free-fall metal detectors, suitable for inspecting bulk materials as they fall through a detector’s aperture.

When a metal contaminant is detected, the contaminated material is usually separated from the clean plastic. This process is often automated, with pneumatic rejection systems or air-blast rejection systems that can quickly remove the contaminated material from the production line.

In addition to metal detectors, magnetic separators and metal detection systems, like those provided by Bunting, can also aid in removing metal contamination from plastic waste. Magnetic separators use magnets to attract metal particles and remove them from the plastic, while metal detection systems utilize sensors to identify the presence of metals in the material.

To detect the presence of metal contaminants in plastic pellets, laboratory testing devices like the one mentioned by can automatically detect and visualize metallic contamination from 50µm in size.

In summary, detecting and handling metal contamination in plastics is a crucial aspect of the recycling and manufacturing process. By using metal detectors, magnetic separators, and laboratory testing devices, the plastics industry can ensure a high level of product purity and safety while preventing potential equipment blockages and quality issues.

Service and Support

Inside Accessibility

A plastic crusher machine requires easy access to internal components for maintenance and cleaning. This ensures the equipment is always functioning optimally and can help extend its lifespan. Manufacturers should offer designs that provide quick and easy access to internal parts, without compromising on safety features or operator workspaces.

Skilled Field Service

A comprehensive field service is essential for the smooth operation of a plastic crusher. Access to skilled technicians and engineers ensures that any potential issues can be addressed and resolved quickly, minimizing downtime for the equipment. A reliable field service should include:

  • On-site support, where technicians visit the client’s location to diagnose and repair any issues.
  • A helpline or support center, where clients can report problems and receive guidance on how to resolve them.
  • Spare parts availability, ensuring the rapid delivery of replacement components when needed.

Client Services

In addition to providing technical assistance, manufacturers should also offer a range of client services to support the proper use and maintenance of the plastic crusher. These services can include:

  1. Training: Hands-on training for machine operators, covering topics such as safe operation, cleaning, and basic troubleshooting techniques.
  2. Preventative maintenance: Regular inspections and service visits to help maintain the equipment and identify potential issues before they escalate.
  3. Transport: Assistance with securing and transporting the plastic crusher to a client’s location, ensuring that the equipment arrives safely and is correctly installed.

A robust service and support framework is essential for maximizing the performance, efficiency, and lifespan of a plastic crusher. By offering a combination of inside accessibility, skilled field service, and comprehensive client services, clients can confidently invest in a plastic crusher, knowing that the manufacturer stands behind their product and is committed to offering ongoing support.

Industry Applications

Plastic Recycling

Plastic crushers play a significant role in the plastic recycling industry. They are mainly used for breaking down solid plastic waste into smaller pieces that can be easily and efficiently recycled (source: Wiscon-Tech). This process reduces the volume of waste and enables further granularization in grinding mills or pulverizers (source: GlobalSpec). Common waste plastic materials that can be processed include purgings, sprue, gates, and rejects.

Various factors such as feed and collection methods, capacity, and output size should be considered when selecting a suitable plastic crusher (source: Wanrooetech). The crushed plastic flakes can then be cleaned and sold or transformed into granules, increasing their value.

Waste Rubber Products

Aside from plastic materials, industrial crushers can also process waste rubber products. Rubber waste, such as tire shreds, can be subjected to size reduction processes through the use of specialized crushers. This process facilitates the subsequent recycling or repurposing of the waste rubber material into new products, such as rubber mats or playground surfaces.


The operation of a plastic crusher involves holding the feed material between two solid surfaces and applying sufficient force to fracture or deform the material (source: GlobalSpec). Crushers made of thickened carbon steel are quite durable and have a long usage life (source: Fangtai Plastic Machine). These machines can often be used in conjunction with other recycling equipment to form a complete recycling line.

A typical plastic crusher has a rotor length ranging from 300 to 1500mm and can produce varying capacities from 400 kg/hr to 1500 kg/hr (source: Wiscon-Tech). This equipment can handle various types of plastic waste such as lumps, sheets, films, pipes, tails, flashes, bottles, sprues, runners, and rejects. The selection of a suitable crusher depends on factors such as the material composition, desired output size, and the specific requirements of the recycling process.

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