Crushers and shredders for plastic - types of shredders, operating principles and prices. Twin Shaft Shredders Household Plastic Shredder

Most polymer materials are chemically inert and not biodegradable.

There is also, but its share in world production is very small.

The durability of polymers has reverse side– waste, including industrial waste, must be disposed of.

Landfilling or burning of plastics causes irreparable harm ecology. Therefore, polymer manufacturers and solid waste disposal enterprises are mastering recycling.

This is a set of activities, the diagram of which looks like this:

• waste collection and sorting;
• processing into secondary raw materials;
• production of final products.

In this article we will talk about plastic shredders.

Polymer processing is impossible without shredders and crushers. They are used for grinding, that is, obtaining pieces of a given size.

Fraction size- one of the key technical parameters equipment, and it determines how costly the next stage of processing – granulation – will be.

In some industries, technology allows for the mixing of plastic chips into the feedstock. Here, the uniformity of grinding, the absence of dust and too large pieces plays an even more important role.

Types of shredders and crushers

Manufacturers and equipment suppliers are often faced with a client’s request to select a universal shredder or crusher that will work with all types of plastics and produce almost finished granulate.

This task is practically impossible, since polymer materials differ in a number of parameters:

• physical and mechanical properties - strength, impact strength, friction coefficient, softening temperature;
• structure - they are solid, fibrous, cellular, composite;
• shape and dimensions.

In addition, consumers do not always understand the purpose and operating principle of the equipment. To avoid confusion, we note that both machines stand next to each other in a complete production line: the shredder performs the primary grinding of waste, and the crusher does the secondary. Their designs may be the same.

The division into two stages is carried out to optimize production. For example, grinding a thick-walled 200-liter barrel to a fraction the right size will require either a high-power drive or high time costs.

Two-stage crushing allows reduce energy costs And increase processing speed.

Some manufacturers make machines that combine a shredder and a crusher. For example, the international group of companies TRIA has developed a series of combines for processing large blocks and thick-walled blow moldings. However, they are not suitable for working with small-sized waste - , -.

Crushing equipment differs in design, operating principle and type of material being processed.

Processed materials and methods of exposure

All recyclable materials can be divided into three types:

1. Film— polypropylene, acrylic, polyethylene and PVC films are highly elastic. To grind them, you need cutting or tearing installations.
2. Small and thin-walled— these include PET containers, small canisters for fuels and lubricants, plastic pipes. Shredders should be equipped with stronger blades or teeth.
3. Large and thick-walled— sprues, profiles and molding defects are crushed by impact, squeezing or abrasion.

The dimensions of the loading window, hopper, filling system, actuator and profiling sieve depend on the dimensions of the waste. Feeding can be done manually, using a conveyor belt or a lifting machine.

Some types of machines are integrated into the production lines of enterprises, others are installed separately.

There are a number of solutions on a trailed chassis, such shredders delivered to the venue temporary work . Many manufacturers offer their customers modular designs with a set of options that allow the same mechanisms to be used in different conditions.

Operating principles of shredders

There are three types of shredders depending on the principle of operation:

• shock action;
• compressive;
• cutting and tearing.

Impact shredders, or hammer crushers, are often used in the mining industry and processing plants , are also used to destroy polymers.

They fit for working with gates and large waste made of fragile plastics. The advantages of such machines include high productivity and the ability to work with hard-to-grind materials.

However, they have significant flaws:

• large mass of the frame— some models can only be installed on a prepared reinforced concrete base;
• high rotation speed in combination with hinged hammers make the mechanism a source of noise and vibration.

Compression devices—jaw and cone crushers—are designed for grinding the largest wastes. However, they are not able to cope with viscous polymers such as ABS plastic or polyurethane.

The machines are equipped with a powerful drive; electric motors and hydraulic cylinders are used as power units.

Cutting and breaking shredders, or rotary shredders, are equipped with knives and teeth. They are suitable for grinding most types polymer waste. Among the manufacturers' offers models for industrial use can be found, medium and small businesses.

Common designs

Shredders for plastics are made according to three different kinematic schemes. They are:

1. Single-shaft. The rotor rotates in a working chamber, or stator. The raw material is fed through the loading window, and the crushed material, under its own weight, exits through the profiling sieve. There are also machines with forced pneumatic unloading. One of the main elements of a single-shaft shredder for medium and large waste is a hydraulic press plate. It presses pieces of plastic against the rotor and ensures that they are captured by teeth or knives. Single-shaft designs are suitable for primary grinding of high-hardness polymers.
2. Twin-shaft. Systems with two rotors have a higher degree of grinding. On the loading side, the shafts rotate towards each other. The gripping conditions in a two-rotor machine make it possible to do without a pre-presser. High torque makes it possible to process waste of soft elastic plastics, elastomers, and rubber goods.
3. Four-shaft. The system includes two main (cutting) and two auxiliary (feed) shafts. Such machines are designed for crushing large-sized waste, including hollow waste: cans, barrels, cans. The knives of the feed rotors are spaced apart, but have a positive overlap with the knives of the working shafts, and therefore also participate in the grinding process.

The largest demand for plastic recycling use rotary shredders and crushers.

They achieve the required crushing depth with high productivity, are easy to operate and do not require high maintenance costs.

Grinding is performed with knives attached to the rotor and stator. For light and thin plastics, machines with high speed rotation, for solid and large waste - low.

Depending on the type of plastic, knives of the following designs are used:

• disk;
• straight;
• oblique;
• V-shaped;
• cascading.

Highly specialized machines

The largest share of waste in the production of polymer film comes from the edges. To crush it and remove it from the work area specialized installations have been developed.

Venti Oelde produces a range of industrial burst fans. There are no counterknives in their design, and the edges of the blades have a sawtooth shape. Fine teeth grab the edge and pull it until it breaks, and the crushed waste is directed by air flow into the receiving hopper.

Shredding of polyethylene films and extruded polystyrene foam is accompanied by heating of the material itself and the knives.

To avoid material sticking, crushers are equipped with water cooling systems. However, some manufacturers self-heating is used to obtain agglomerate– the processing stage following grinding.

They are high-speed (≥1200 min -1) crushers that produce dense balls with a diameter of 3 – 15 mm. If the initial raw material did not contain impurities, the agglomerate is sent for reuse without additional processing.

Equipment performance: industrial and mini

You need to choose a plastic shredder for specific tasks taking into account its performance.

Using the example of the ATLASMASH LLC family of shredders, it can be seen that the spread of this parameter is 50 – 3500 kg per hour.

The consumers of such installations are enterprises not involved in recycling.

The WS line is a medium-performance model designed for commercial use. WN – industrial shredders designed for high level downloads.

It is also worth paying attention to machine drive power. The most productive models consume up to 160 kW/h electricity.

Plastic shredder prices

Approximate prices for polymer shredders from various companies are presented in the table:

Most manufacturers of shredders and crushers for plastic do not lay out prices for their equipment, but make a commercial offer at the request of the client after studying all his needs.

For example, installing a cooling system or a cyclone filter can lead to a significant increase in the cost of equipment.

A decision on the advisability of purchasing a shredder or crusher should be made only after calculations and consultations with an economist and the manufacturer.

Sometimes a mini crusher will be enough. In cases where the amount of polymer waste does not reach 1 ton per year, optimal solution there will be take mobile shredder for rent or enter into a collection agreement, removal and disposal with a specialized company.

Results

Crusher and shredder are indispensable devices in plastic processing. The right shredder will give you a good start and make it as cost-effective as possible.

Buying a plastic shredder is profitable and without headaches. Assembly, delivery, commissioning

For polymer processing, we suggest you familiarize yourself with single-rotor and double-rotor shredders. Quality equipment from good manufacturer- that's what everyone needs. And we will help you choose a plastic shredder, buy it and start using it.

• Why is a plastic shredder better than a crusher?

  The shredder works more efficiently, and most importantly, with less waste - it does not make much noise and does not leave dust behind. In addition, the size of the pieces of plastic can be completely different - the shredder can handle everything. The plastic shredder is very resistant to any type of damage - the knives and other parts do not wear out for a very long time.

• Shredder Types

  Shredders for plastic can be completely different - depending on the amount of material that is collected in your production, you can choose a shredder based on size and technical specifications. The fraction on the output hole is marked with productivity - for example, 50 mm, but the size of the hole can be changed depending on your wishes and needs. In addition, our company offers film shredders.

Positive qualities

Buy a shredder, which processes plastic without additional costs, from us, and you will receive the following device:

• With minimal noise;
• Compact and convenient design;
• Ease of operation;
• High-quality and reliable knives on the rotor;
• Economical costs – minimum electricity consumption and machine maintenance;
• The design of the working chamber is suitable for processing plastics of large and small sizes.
• Highly efficient performance;
• Good price and availability of all models and spare parts of interest in our warehouse in Moscow;
• The shredder can be configured for more convenient use, as well as depending on the operating conditions that are optimized in your production.

Processing polymers is not such a complicated technological process if you have the space, specialists and a plastic shredder. Thanks to correct adherence technological process for minimum quantity time, you can clean up a large pile of garbage and get a new product needed for the production of plastic goods.

• Where is a plastic shredder used?

  The main customers of the solid waste shredder are small and large enterprises specializing in the manufacture of plastic products, companies that collect waste for the purpose of subsequent disposal, and enterprises whose activities are related to the production of plastic products.

  The process of processing used plastic and rejecting it using high-quality equipment guarantees the following advantages:

  • high productivity of granules of a certain size and shape;
  • reducing the cost of the resulting product;
  • increasing the number of sales;
  • saving costs on purchasing parts;
  • quick profit generation;
  • achieving financial independence.

  To realize your dream and develop your plastic recycling business, all that’s left is one small thing: buy a plastic shredder. We invite you to learn more about how to find us and what you need to do this.

• How to choose a shredder for LDPE?

  Select product high quality Just. To do this, you can get advice from our specialist or fill out an online application on the company’s official website. By specifying contact details, equipment requirements, managers as much as possible short terms will select the unit required quality. There are several types of shredders on the market. Knowing the final purpose of the installation and the preliminary loading parameters, our specialists will never make mistakes.

Twin-shaft shredders are used for crushing materials (plastic, wood, metal) and are used on such objects as:

• waste sorting complexes;
• lines for processing and procurement of recyclable materials;
• manufacturing enterprises.

A twin-shaft crusher is a device equipped with two rotating different sides rotors. Knives are installed on the shafts. There are various options knives, for example, knives can be disk type and removable knives on a shaft. The knives on the shafts are located in such a way as not to touch each other and crush the material caught between them. The number of knives depends on the performance of the shredder and the type of material to be crushed. In disk-type shredders, when sharpening, it is necessary to remove the disks for sharpening. In a shredder with removable knives, the knives are removed and turned over to the sharp side for further use. The shredder design may include an output conveyor with an installed metal catcher.

Industrial twin-roll crushers are used for processing metal products, wood, plastic, industrial waste, rubber products, bottles, branches, tree stumps.

Buy a twin-shaft crusher for wood, plastic, metal and rubber products

When ordering a twin-shaft shredder, you must first consult with the manager of Netmus LLC to obtain the exact specifications for the equipment, and the price will also be calculated. Industrial shredders are manufactured individually to achieve maximum performance in accordance with production tasks (for example, shredding plastic or wood, producing wood chips). The right industrial shredder will last for many years. The quality of equipment manufactured in Europe to the highest standards is beyond criticism.

Plastic recycling – one of the freest niches in Russia for doing business.

However, the issue of opening it most often depends on the cost of the equipment.

Entrepreneurs often start not with a full processing cycle with finished granulate at the output, but with the collection and grinding of polymer waste.

Even in this case, purchasing a shredder and (or) crusher may not be affordable. One of the most discussed solutions to the problem is making your own shredder.

Such projects are quite feasible if two “constant quantities” are known - raw materials and product.

Both types of equipment perform the same task - crushing.

When processing plastics This process is usually divided into two stages:

• coarse grinding - shredders are used for this;
• obtaining fine crumbs - a crusher is used for this.

The operating principle and kinematics of both units are most often the same, and they differ only in some details, for example, the size of the sieve cell, the overlap of the knives and the configuration of the cutting edges.

The process is divided into two stages to improve productivity and optimization of energy costs.

Shredder design for plastics

When choosing the design of a plastic shredder, you should pay attention to the proposals of equipment manufacturers.

It is better to take other people’s work as a basis for a project and have certain guidelines than to reinvent the wheel and end up with a non-working model.

The most popular are single- and double-shaft rotary shredders.

Single-shaft

Single shaft shredders are used for initial shredding most types of polymers.

It consists of a rotor on which movable knives (2) are fixed and a housing with fixed or stator knives (1). The raw materials are fed through the loading window from above, and the finished crumbs are poured under their own weight through the calibrating sieve (3).

The shredding process involves repeated cutting and continues until all the plastic has gone into the receiving hopper.

Rotary knives configuration selected depending on the material being processed:

1. Dovetail and slanted– for recycling and other soft waste.
2. Direct– for crushing sprues, boxes, thick-walled blow moldings, PET bottles. Such knives are often made in the form of separate segments, which are arranged in cascades. Segmentation is performed to reduce shock loads on the drive, reduce noise and vibration.

Stator knives for single-shaft polymer crushers are made solid (type P).

Twin-shaft

The rotor and stator knives on such crushers are arranged in a checkerboard pattern, and the shafts rotate in counter directions.

Low productivity machines with a small working chamber are carried out with single drive, the teeth on the rotary knives serve to capture and crush waste.

Grinding is also performed by the side surfaces (as in disc shears).

Where can I get the drawings?

You need to understand that manufacturers of equipment for shredders and crushers won't post it drawings in the public domain.

The easiest way to get diagrams for a homemade shredder or crusher is in two ways:

1. Read forums on the topic, like this. The likelihood of finding accurate and detailed drawings of plastic shredders is very low. Often, resource users recycle some unclaimed equipment from a related industry, for example, a lopper. And if a crusher is made from scratch, few people care about documenting all stages of production. However, it is worth reading the forums: analysis of discussions and other people's mistakes design will help you make a more advanced plastic shredder with your own hands.
2. Take measurements from the existing one chopper Get full information It won’t work, because the owner won’t let you disassemble a running machine. But in making your own homemade crusher Even a visual assessment will help.

Many attempts to make a crusher on their own come to a standstill because the designer tries snap to an existing node. For example, “fit” all the elements to a worm gearbox found in the garage.

An attempt to reduce the cost of a design using secondary parts, as a rule, leads to mistakes.

Initial data for design

It is better to start production with a clear definition of the tasks of the shredder, that is, you need to know the type and quantity of raw materials being processed, and the size of the output fraction.

After this, we find a model from any well-known manufacturer that fits these parameters and take its technical characteristics:

• engine power;
• loading window dimensions;
• number and diameter of rotors;
• knife configuration.

Drafting

For example, we determined that under production tasks A twin-shaft shredder with low rotor speed is suitable.

His project necessarily includes:

• engine selection by power;
• calculation of the gear ratio and selection of the factory model;
• determination of the diameter and length of the rotors (based on the size of the loading window);
• calculation of shafts for strength;
• selection of bearing supports.

You will need a tutorial for this.“Machine parts” for universities. You will also have to look at GOSTs for threaded connections, reference books on gearboxes, bearings, couplings and other assembly units.

When using hardware foreign production often inconsistencies arise standardization, for example, “their” retaining rings are thicker than “ours” with equal diameters.

This must be taken into account when assigning groove dimensions.

After calculations it is necessary arrange the components on graph paper or in an editor like AutoCAD, determine the dimensions of the body parts and the frame.

You need to approach this task responsibly so as not to miss anything. Sometimes the protruding head of an “unaccounted for” bolt leads to the car has to be rebuilt. After this, detailing is done - a drawing of each part separately.

Drive design

In factory crushing plants, two methods are used to transmit rotation from the motor to the gearbox:

1. Direct drive(via coupling). Torque transmission occurs without loss, the design is compact in size. If you manage to select a ready-made geared motor, the dimensions and weight of the installation will be even smaller. However, in this case, it is necessary to provide for manual (and ideally automatic) reversing in case of jamming of the rotors.
2. Belting. Efficiency losses and relatively high dimensions are compensated by the smooth start of the mechanism. If the shredder becomes jammed, the only risk is that the belt will break or slip.

The transmission of rotation between the rotors (in the case of using one engine) is most often carried out through an open gear drive. When designing, you need to be prepared to calculate it. More likely, gears will have to be ordered.

Knives

Finding a suitable knife configuration is not difficult.

Many manufacturers make no secret of this.

Anyone interested in the question can choose the appropriate profile and change the dimensions for your rotor, make the required number of teeth.

Knives will also have to be ordered from a company engaged in waterjet, plasma or laser cutting. Afterwards you will have to grind them to the same size along the plane.

The above also applies to fixed knives. Only for them you still have to think about how to attach them to the body.

Most often, counterknives are drilled with two through holes on the sidewalls and tightened with pins through spacer bushings.

Another pair of blind holes with threads are made on the side of the body for fastening to it with bolts.

Another important question– material. This can be one of the spring (65G, 60S2, 65S2VA) or die (X12MF) steels. Anyway will have to order also literate heat treatment with control of the hardness of each finished knife.

Shafts

The standard blade mounting configuration for most manufacturers is hexagon. That is, a blank for the shaft can serve rolled profile, the ends of which are machined for bearings, gears, etc.

The optimal choice is steel 40, 45, 40X with improvement (hardening + high tempering).

Bearing units

You can use ready-made bearing units of a self-aligning design.

They “forgive” errors in the alignment of the holes, in which conventional radial bearings will warp and overheat.

However, compared to conventional bearings the cost of such units is much higher.

In addition, the dimensions of their housings often do not allow maintaining the required center-to-axle distance between the rotors.

To avoid misalignment, the sidewalls of the crusher body are used as axle boxes. The mounting holes are bored in a machine with a four-jaw spindle, placing the parts together.

If it is not possible to make a housing with coaxial holes, you can select double-row spherical bearings suitable for load-carrying capacity.

Rotors

One of the main requirements for rotors is the presence guaranteed clearance between the sides of the knives. Otherwise they will rub together, the mechanism may even jam.

The width of the spacer bushings should be larger. They also need to be sanded to the same size.

Particular attention should be paid to axial adjustment.

The design of the shafts must include the possibility displace the entire set of knives and bushings to tenths of a millimeter and reliably fix it when the side gap is uniform.

Most often, threaded parts are made on the shafts, and the position of the knives is fixed with nuts.

Assembly of finished units

For the design to be repairable, the body should not be welded.

It is better to make a bolted connection.

Then chopper can be taken apart at any time for sharpening or replacing knives.

One of the common problems with rotating mechanisms is increased vibration.

To avoid this phenomenon, it is necessary to align the actuator, gearbox and motor, i.e., align their axes.

Another reason for vibration is imbalance(imbalance) rotors. To eliminate it, you need to carry out balancing.

Useful video

We invite you to watch a video on how to implement the idea of ​​a plastic recycling business using homemade equipment:

Conclusion

Were considered not all the difficulties, which will have to be encountered in the process of designing and assembling a plastic shredder.

Manufacturing can only be called independent, since it requires a whole fleet of machines, and some units have to be purchased assembled. All the process may take months, and financial investments will be required in any case.

After developing the project “on paper” worth calculating economic efficiency events: sum up the costs of procurement and processing, and then compare with the price of a “factory” shredder.

Those who have already had experience in manufacturing shredders believe that the idea is justified in two cases: if there are no strict time restrictions or if it is planned to establish serial production of such units. For practical plastic recycling tasks, it is usually It’s easier to choose a ready-made model.