Corrugated Pipe Extrusion Line: The Comprehensive Importers Guide in 2018

Plastic plays an essential role in piping systems in our modern world.

And if you want to manufacture plastic pipes:

Today, I will introduce you to the manufacturing process of corrugated pipes and the corrugated pipe plastic extrusion line.

Straightway, let me introduce you to three types of plastic materials we will be dealing with:

• PP (Polypropylene)- a thermoplastic with numerous applications.
• PE (Polythene) – the most common plastic in the world.

-There are various densities of PE (Low Density, Medium Density & High Density)

In this guide, we will look at High Density Polythene (HDPE) for the HDPE pipe extrusion machine.

• PVC (Polyvinyl chloride) – The third mostly widely used plastic in the world.

By the end of this guide, you will have enough knowledge about:

• Corrugated pipe extrusion line for PVC PP PE double-wall corrugated drainage pipes
• Corrugate pipe extrusion line for PVC PP PE single-wall corrugated cable protection pipes

Great, let’s start:

Chapter 1: What is a Corrugated Pipe and Corrugated Extrusion Machine?

1.1 What is a corrugated pipe?

A corrugated pipe is a hollow pipe marked a series of fallows and valleys on its surface.

Figure 1: Metal Corrugated Pipes

For many years, metal corrugated pipes have been the go to material by engineers designing drainage systems for roads and other construction works.

At the present moment, plastic corrugated pipes are gaining popularity.

They are used to channel both water and oil.

Let’s see the different types of corrugated plastic pipes in the market:

1.1.2 What are HDPE /PVC/PP corrugated pipe?

First up, we know that these corrugated pipes made of plastic.
The difference is in the type of plastic.

HDPE corrugated pipes are made using high density PE.

Figure 2 HDPE Pipe installation in Mexico

While PVC corrugated pipes are made from PVC.

Next, I want to introduce you to two more sub-types of corrugated pipes:

• Single Walled Corrugated Pipes

Basically, single walled corrugated pipes have one layer of an homogeneous thermoplastic material such as PE or PVC.

They are also flexible and you can coil them.

Figure 3: Single Walled HDPE Pipe

• Double Walled Corrugated Pipes (DWC Pipes)

DWC pipes, on the other hand, have two layers. An outside corrugated layer and the inside layer, which is plain and smooth.

The purpose of using two layers is to attain the best mechanical and performance requirement even in harsh places of use.

For instance, DWC pipes have a high impact, corrosion and compression resistance.

We’ll talk more about the properties of DWC later in this guide.

1.2 Types of corrugated Pipe Extrusion Machines

Okay, you have seen the structural distinction of corrugated pipes.

This along with the diameter of the pipe you want to manufacture will determine the machines you need.

Double wall corrugated pipe extrusion line

Double walled corrugate pipes have a range of diameters; from small to big pipes.

The dimensions defer based on the places of use or customer’s requirements.

Our double wall corrugated pipe extrusion line can make HDPE DWC pipes with the following specifications:

Double wall pipes	HDPE Pipe Outside Diameter	PVC Pipe Outside Diameter
1	50-160mm	50-160mm
2	200-800mm	200-500mm
3	600-1200mm	N/a

Single wall corrugated pipe extrusion line

Our single wall corrugate pipe extrusion machine can make pipes from OD 16-63mm.

These pipes are flexible, and widely used as conduct pipes for electrical wires.

Here are the diameters our single walled plastic corrugated pipe production line makes:

Single wall pipes	HDPE Pipe Outside Diameter	PVC Pipe Outside Diameter
1	9-50mm	9-50mm
2	50-160mm	50-160mm

1.3 Why you should manufacture corrugated pipes?

Figure 4: Manufacture of Double Wall HDPE Pipe

Starting a corrugated pipe plant is great! And the following reasons prove this:

• Material saving

When you manufacture corrugated pipes, you save up to 60% of raw materials had you gone with solid walled pipes.

Though they are lighter, these pipes are strengthen by the rings in their structure.

• Easy handling

Corrugated pipes are lighter, which makes them easy to handle and transport.

So you will require less personnel for your corrugated plant and the same benefits will trickle down to the end user.

• Less ecological footprint

By cutting down on the material used, your factory will have far less impact on the environment.

In addition, manufacturing corrugated pipes produces less carbon iv oxide emission compared to making concrete pipes.

What’s more, you can recycle corrugated pipes them.

Conclusion

In this chapter, I have introduced you to corrugated pipes. And why you a manufacture you should consider making them.

Join me in next chapter as we get more technical and discover different aspects of the corrugated pipe extrusion machine.

• Chapter 2: What are the parts of the Double Wall Corrugated Pipe Extrusion Machine?

Figure 5: Double walled corrugated pipe production line

At first the corrugated Pipe making line may look complex.

But, you can easily understand all the parts of the corrugated pipe production line along with the processes taking place in each machine.

Generally, we have the following processes occurring:

• Preparation of raw materials
• Extrusion
• Corrugation
• Cooling
• Finishing/cutting

Preparation of the raw materials

You will start by ordering raw materials from different suppliers.

Once the raw materials arrive at your factory, the quality controller will take samples and carry out tests see if they are compliant.

You will establish your own quality control measures such as checking for the moisture content, density or melt flow rate.

Then, the materials are stored awaiting production.

Before production begins, the raw materials have to be prepared.

NOTE:

If your using PVC material to manufacture corrugated pipes, there are two preparation processes you will perform on PVC.

First, we have mixing the PVC (thermoplastic material) with other additives.

Second, you need to heat the PVC resin to remove any moisture it contains –then rapidly cool it to prevent early plasticization.

The equipment to perform these processes is the hot and cool mixer used for preparing PVC resin.

Figure 6: Mixing Machine

In the hot tank, the PVC resin with other additives is heated to over 100^oc and agitated by a stainless steel blade.

The material mix is then discharged into the cooling tank, which cools it quickly to prevent early plastization or decay.

From the cooling tank, you will discharge the materials into a spring loader.

It loads the material into the hopper of the extruder.

While product mixtures vary depending on the manufacturer, it’s common practise to include carbon black, which is a UV inhibitor and pigment.

Carbon black is used for sewer and above ground uses of corrugated pipes.

On the other hand, the yellow pigment is used for pipes used in natural gas production.

Extrusion by two single-screw extruders (co-extrusion)

Extrusion involves softening the thermoplastic material.

This softening is what we call plasticization.

The equipment used to perform plasticization is called the extruder.

NOTE:

You may use the following thermoplastic materials

• PVC
• HDPE
• PP
  When we make PVC corrugated pipes, we need to use the conical twin screw extruder.

Here is a video that explains how a twin screw extruder works:

When we make double walled HDPE/PP corrugated pipes, we use two single screw extruders.

Figure 7: Single screw extruders

So how does the extruder work?

To see how everything works, let’s take a peak inside the extruder:

Figure 8: Diagram of single screw extruder

The screw is continuously driven at a constant speed by the electric motor.

From the hopper, the raw material descend onto the rotating screw by gravity.

Heat required to soften the thermoplastic material is supplied by the heaters.

And there are normally 4 to 6 heat zones –with temperature increasing down the barrel.

Each zone is controlled by a separate thermocouple.

Cooling fans prevent overheating.

You will notice that the space between the screw and barrel decreases down the barrel.

This increases the compression forces of the screw against the plastic.

Heat is also generated by friction.

Once you heat the extruder to normal operation temperatures, you can maintain temperature by the shear heat generated by the screw against the material.

The temperature required for complete plastization is about 400˚F to 490˚F.

https://youtu.be/Ka1ROrzcqPM

The pressure required for melting is also very high at 2000 to 4000 psi.

This high pressure allows the extruder to force the materials out into the die.

The molten plastic is called the extrudate. And it passes through a breaker plate (that consists of one or two wire mesh screens)

The breaker place will allow you to prevent contaminants from entering the pipe.

Co-extrusion

Co-extrusion refers to the process of combining two or more plastic molten streams from two or more extruders to make a plastic pipe with more than one layer.
Keep in mind that, for the PE PP double wall corrugated pipe producing line, we combine two single screw extruders.

So, the two extruders co-extruding allows you to make the double-walled corrugated pipe.

Having two layers instead of one, will give the pipe better mechanical properties than using a single polymer layer.

So, how do the polymers combine?

The two extrudate are combined in the co-extrusion die.

We use a double-layer spiral co-extrusion die in our PE PP corrugated pipe extrusion line.

This die is positioned behind the breaker plate.

Shaping of the molten thermoplastic layers into a tube takes place at the exit of die.

Figure 9: Labeled diagram of co-extrusion die

However, this shape is later altered and the HDPE pipe shaped again in the corrugator by the molds.

The equipment after the die that’s performs these tasks is called the down stream equipment/post extrusion equipment or haul off.

NOTE:

You can use single screw extruders for many types of plastic extrusion products.

However, the post extrusion equipment varies with product you’re manufacturing.

Next, let’s look at how the corrugate pipes get their final shape.

  Corrugation by the horizontal structure corrugator

So why can we still shape a plastic pipe even after it leaves the die?

This is because plastic takes some time to cool.

Actually, the time it takes to cool will determine the speed a which the line operates.

In our double wall corrugated pipe extrusion line for drainage pipes, final shaping or moulding is done by the horizontal structure corrugator.

Here is a video of the corrugator in action:

The corrugator has rotating molds, which makes the moulding process continuous.

Vacuum technology is also used in the molds.

Due the presence of a vacuum inside the corrugated, the outside surface of the hot PE PVC or PP pipe is pulled against the mould blocks.

This helps us get the desired geometric shape.

Figure 10: Molds for double walled corrugated pipe

We also have to cool down the molds for proper corrugation of the PP PE PVC corrugated plastic pipe.

You can use either water or air to cool down the molds.

In an air-cooling corrugator, cool air is blown over the surface of the molds.

Air cooling is mostly used in North America and in most corrugators around the world.

In a water-cooled system, water flows in jackets inside the molds.

You will commonly find water-cooled systems in Europe.

Water cooling offers more cooling efficiency and allows for higher output.

This ensures rapid heat dispersion by the HDPE pipes.

Cooling in the spay tank

Figure 11: Spray tank for corrugated pipes

After the HDPE pipe leaves the corrugators(forming die), we have to cool it further in order to retain the pipe’s circular shape and dimensions.

Since when plastic is still hot, it is prone to deform when handled.

Cooling takes place in the spray tank.

Our spray tank’s inner surface has water nozzles that spray cool water on the pipe as it passes through.

There is a cooling unit to chill the water to temperatures of below 10°C.

NOTE:
For double walled corrugated pipes with large diameters, spray cooling is used.

And when the diameter is small, for instance, single walled corrugated pipes, we can immerse them in water baths.
As the HDPE/PP/PVC double walled corrugated pipe leaves the spray tank it’s now rigid for cutting.

 Cutting, packing and storing

Figure 12: Cutting machine

In the final step of the manufacturing process of corrugated plastic pipes, we cut the pipes into lengthwise pieces.

Currently, the prevailing length is 3 or 6 meters.

NOTE:
Pipes need to be labeled after several intervals.

You may include information about the pipe’s size, company’s name, the plastic used, among other details.

You can easily mark a pipe with a inkjet printer.

Your quality control department will also need to regularly test samples to make sure that each equipment in the line is functioning correctly.

Double Wall Corrugated Pipe Production Line Technical data

PE/PP corrugated pipe extrusion line

Pipe size	Type	Extruder	Output
50-160mm	double wall	SJ75/33 + SJ65/33	350-400KG/H
200-800mm	Double wall	SJ120/33 + SJ90/33	600-1000KG/H
800-1200mm	Double wall	SJ90/38 + SJ75/38	1200-1500KG/H

PVC corrugated pipe extrusion line

Pipe size	Type	Extruder	Output
50-160mm	double wall	SJ55/110 + SJZ51/105	200-300KG/H
200-500mm	Double wall	SJZ80/156 + SJZ65/132	500-650KG/H

Advantages of Benk’s Double Wall Corrugated Pipe Production Line

1. Our big screen LCD human-computer interface system enables enhanced oversight and simplified management of the manufacturing process.
2. Germany Simens 12inch touch screen and PLC control system.
3. You will find it easy and convenient to change and align different forming moulds.
4. The water cooled molds made of high quality aluminum alloy make for good heat dispersion and hot corrosion resistance.
5. Visualization for water pressure and temperature on the main display with alarm function.
6. Automatic central lubrication system.
7. Precise lateral and height adjustment of forming machine.
8. High output.
9. Easy operation and maintenance
10. Our corrugated pipe production line takes up minimum space.
11. You can also choose from a wide array of raw materials to manufacture pipes such as PP, PE and PVC.

Applications of PE PP PVC Double wall corrugated pipe

There are many uses of double walled corrugated pipes in today’s world.

The place of use is dictated by the pipe’s diameter.

Note that, double wall corrugated pipes range from 20mm to 3 meters in outside diameter.

Usually, pipes with an outside diameter of 50 mm to 3000 mm are used for pluvial sewer systems, drainage systems for roads, highways, and railways.

Other uses of double wall corrugated pipes include:

• Cable protection
• Land reclamation
• Anti-flood systems
• fountains
• Residential area
• Road and railway engineering
• Waste landfill
• Tunnel, subway
• Green belts
• Sports ground and water content on the high side slope protection

Conclusion

In this chapter, we have explore the various functions and processes taking place in the PE PP PVC Double wall corrugated pipe producing line.

You have seen how your customers can use the corrugated pipes.

In the next chapter, we will look at the single wall corrugated pipe production line.

Chapter 3: What are parts of the Single Wall Corrugated Pipe Extrusion Machine?

Figure 13: Single Wall Flexible Corrugated Pipes

Equipment required in the single wall corrugated pipe extrusion line differs as per the pipe’s sizes and production speed.

You can make single wall pipes with outside diameters of 9-250mm.

Another thing to note, is that we use just one extruder instead of two.

This is because, the single walled pipe has one layer of homogeneous thermoplastic material, which can be:

• PE
• PP
• PVC

This means this line will be less expensive and smaller.

Characteristics of single wall corrugated pipes include:

• Corrosion resistance
• Anti-abrasion
• High strength
• Highly flexible
• Wide operation temperatures (30 – 100^oC for PE single wall corrugated pipes)
• Light weight but still rigid and durable.

Single walled corrugated pipes are commonly sold in coils with 30-50 meters or cut into 6m, 9m pieces.

So, how Plastic PVC PP PE single wall corrugated pipes used?

Single walled corrugated pipe with outside diameters of up to 63mm are widely used for cable protection.

For example, in machine circuits for food machinery, electrical equipment, motors etc.

Single wall pipes with larger outside diameters such as 75mm onwards can be used as drainage pipes for farmlands, sport venues, golf courses etc.

If you want to make corrugated pipes used as conduits for electrical wires in buildings, you can produce them in various colors such as as yellow, red, white, blue and black.

Other uses include:

• Washing machines outlet tubes
• Vacuum cleaners ventilating pipes
• Tubes for air conditioners

Great!

Next, I will show you parts of the single wall corrugated pipe machine and the working process:
Working process for PVC material:

High-speed mixer – feeder – conical twin extruder – die mould – forming machine-puller -winding machine
Working process for PP/PE.

Feeder – single screw extruder – die mould – forming machine -puller- winding machine

  Vacuum Feeder

Figure 14: Vacuum feeder

The vacuum feeder feeds the mixture of thermoplastic material with other additives into the extruder’s hopper.

Our vacuum feeder has a control panel, which you can use to set the load time and wait times.
This allow you to automate the loading.

  Single screw plastic extruder

Figure 15: Extruder and small sized forming molds

For single walled we use only one extruder since we are not co-extruding.

When we use PVC as the main thermoplastic material, you will need a conical double screw extruder for extrusion.

For instance, when you make PVC single wall corrugated pipes for cable protection (9-50mm O.D), you can use the SJZ45/90 conical double screw extruder.

And when we use PE/PP as the major thermoplastic material, we use a single screw extruder.

The choice of extruder also depends on the pipe diameter you want to manufacture and the speed of production.

For instance, we recommend the SJ65/30 extruder single screw extruder for PP/PE single wall corrugated pipes with diameters of 9-50mm.

I know you may be wondering:

What does SJ65/30 mean?

It simply means that the extruder has a screw diameter of 65mm and L/D is 30.

You can also use the SJ55/30 single screw extruder for PP/PE single walled pipes.

So, what is the difference?

Figure 16: Single screw extruder with hopper

The SJ65/30 extruder is a high capacity extruder for high speed production.

While the SJ55/30 functions at normal production speed.

For larger single wall PP PE corrugated pipes (160mm) we use the SJ75/33 extruder.

You will notice that it has a larger screw diameter, which allows it to plasticize more thermoplastic material.

It is very essential to maintain the right temperatures in the extruder for proper plasticization.

We have equipped our extruders with a SIEMENS PLC control system.

However, under normal operation conditions, the screw and barrel are subject to wear.

Factors which influence the rate of wearing include:

• The screw speed
• Barrel/screw straightness
• How the barrel is aligned to the gear box -if they are not properly aligned it can cause metal to metal contact of the screw and barrel leading to excessive wear.
• Type of polymer used e.g. PE.

  Pipe extrusion die

From the extruder, the molten thermoplastic material flows into the die.

The extrusion die will form the plastic into a pipe with a round shape.

You can adjust the extrusion die diameter depending on the pipe outside diameter you want.

Single wall corrugated pipes are very thin compared to other solid pipes such as PPR or solid wall PVC pipes.

The thinness makes it easy to corrugate (or shape them further using the forming machine.

But this posses a problem as the pipe can be blow by air as it leaves the die.
Corrugated forming blocks and the forming machine

The forming moulds/blocks impact the corrugated design on the pipe.

You will use molds that match the pipe’s size.

For instance, we have molds for 20,25,32,40,50,63mm pipes.

They are 72 molds in the forming machine.

For small single wall corrugate pipes there is no forming machine.

Figure 17: Forming molds

Our forming molds have on-line belling to make it easy to connect pipes tightly.

This means you don’t have to buy a belling or socketing machine afterward.

 Cooling

As we aforementioned, as the pipe passes through the forming machine/corrugator, it is still hot and needs to cooled before further handling.

The type of cooling depends on the production speed.

When the PVC PP PE single wall corrugated pipe extrusion line is at normal speed, we use fans for air cooling.

During high speed operation, we can immerse the single walled corrugated pipe in a water bath.

Our foaming machine also runs continuously.

 Haul-off machine

Figure 18: Puller

Hall-off machines are part of the post-extrusion machines.

We use these machines for finishing, cutting, winding or stacking the corrugated pipes.

NOTE:
For single wall PVC PP PE corrugated pipes with small diameters of 9mm to 110mm, we can use an automatic winding machine.

There are two types of winding machines:

• Single station winder – has one spool (disc)

Figure 19: One spool winder

• Double station winder with two spools-we recommend this model for a high speed line because it has a longer winder length.

Generally, you should make sure that the winding speed of the winder is within the range of the production speed.

Note that you can also cut the PE/PVC/PP single wall corrugated pipes into lengths of 3m, 6m, or 9m.

In this case, you will need a cutting machine.

And a stacker machine for automatic unloading and staking.

Single Wall Corrugated Pipe Production Line Technical for PE/PP

Material	PE/PP
Extruder	SJ65 single screw extruder
Pipe range	9-50mm
Capacity	40-60KG	60-80KG
Main motor	22KW	30KW
Mould QTY	42	72
Production speed	8-15m/min	10-25m/min
Cooling type	Air cooling	Water cooling

Single Wall Corrugated Pipe Production Line Technical for PVC

Material	PVC
Extruder	SJZ45/90 conical double screw extruder
Pipe range	9-50mm
Capacity	40-80KG
Main motor	15KW
Mould QTY	42
Production speed	8-15m/min
Cooling type	Air cooling

 

Advantages of Benk’s Single Wall Corrugated Pipe Production Line

There are several reasons to choose our single wall corrugated pipe machine for your factory.

1. Accurate forming of corrugated pipes with durable 45# steel molds that also facilitate fast heat dispersion.
2. You can easily change the molds to manufacture single walled pipes of different sizes.
3. Reliable performance of the extruder. And we can match the extruder to the production speed you want. Each part in the extruder is from top brands in the world. .
4. Our corrugated pipe plant will be easy to operate and manage.
5. High automation level with excellent precision.
6. Durable parts with guaranteed long life.

Conclusion

In this chapter and the previous one, we have look at the single/double wall corrugated pipe extrusion lines.

You can get your production line custom made by us to match the pipe’s diameter you need and production speed.

Next, I will show why you should choose us as your corrugated pipe plant supplier.

• Chapter 4: Why Benk is the reliable Corrugated Pipe Extrusion Machine Supplier China

Figure 20: Single wall pipe draw by the puller

Are you looking for a manufacturer of single/double wall corrugated pipe extrusion lines in China?

Benk is a leading pipe extrusion line manufacturer with other similar lines such as the PVC Pipe Extrusion Machine, HDPE Pipe Extrusion Line, and Corrugated Pipe Extrusion Line.

We have been producing plastic machinery for the past 10 years.

Feel free to talk to us about PVC PE PP tube production corrugated pipe extrusion line.

We will help you regardless if you decide to place and order with us or not.

Reasons you should trust us as your Corrugated Pipe Production Line manufacturer & exporter

1. Excellent pre-sale and after-sale support

Our support team is one of the best.

During the pre-sale process, we will help you choose the right machines/extruder for corrugated pipe manufacturing.

We can also help you come up with diagrams for your production plant.

You will also get electrical and water supply diagrams from our team.

After you purchase our machines, we also offer excellent after-sale services.

We offer installation services and can send our engineer to accompany the machine and help in the installation at your plant.

You will get free formula support from us. And we can recommend reliable raw material suppliers in China.

This will help you can get started quickly

1. Quality assurance

We use the best materials and designs for our machines.

Before we ship any corrugated pipe production line, we assemble it and test it in our workshop.

We will invite you to witness the testing, so you can ascertain the machine meets your needs.

Once in your factory, our machines will serve you for a long time with minimal mechanical products and less downtime.

• World-Renown Brand Parts

We use high-quality parts from renowned brands in our corrugated plastic line.

For instance, Ormon temperature controllers and Siemens PLC.

We will also supply you with free spare parts for the first six months.

And a long warranty of 13 months for any defective parts.

1. Quick Delivery

We ship the machine within 30 working days after you make the payment.

When we have machines ready in our warehouse, we will take less time to ship them.

1. Available Staff Training & Installation support

The engineer who accompanies the machine to your factory can also provide staff training.

You will only pay for the travel, hotel and other expenses. You as buyer will also pay them a reasonable salary of $50 per day.

Conclusion

This guide aims to introduce you to corrugated pipe manufacturing.

It is impossible to know everything there is.

But with the knowledge you have gotten here, you can confidently contact us.

Let us talk about what’s best for your needs.

To get started, ask for a quick quote here.