Connecting wires with caps. Wire connection methods

Reliable, uninterrupted operation of any electrical network depends on the quality of the contacts. A well-made connection of the wires allows a long time to use the wiring without having to look into the junction boxes. There are many ways to ensure a secure joint.

Among them, the least laborious is twisting. The PUE does not directly prohibit it, but the paragraph of the rules describing the methods for making connections and branches does not mention this method among those allowed.

Lack of fixation of the coils can cause the coil to loosen. This will someday lead to a loss of contact density, heating of the junction.

A burnt contact will cause an interruption in the current in the circuit, may cause a short circuit and a fire.

Modern technologies have made it possible to increase the reliability and quality of twists by using Insulating Connecting Clips. The article will introduce the design, tell you how PPE caps are used for joining wire cores.

The connection is made by putting on a suitable brand of PPE on the twisted wires with strong twisting until it stops. Caps for twisting wires are a simple design:

• The plastic sleeve, in the form of a truncated cone with a ribbed surface, is made of durable non-flammable plastic. Being a good dielectric, it provides high-quality electrical insulation. Protrusions can be made from the outer side of the housing. This makes it easier to grip when winding the clamp onto the conductors;
• A conical steel spring or a threaded metal insert is located in the housing bore. Spring steel with an anodized finish that provides good electrical conductivity. When winding onto the joint, the turns strongly compress the stripped ends of the cores between themselves. This provides a tight contact of the conductor surfaces, duplicated by touching the metal of the coils of the spring.

There is no single standardized system for coding PPE parameters. The labeling of products manufactured by one of the domestic manufacturers indicates the connector size. Each clamp size is designed to accommodate different total cross-sections of the cores, they differ in size and body color. The technical documentation decodes the standard size, showing the minimum and maximum sum of the cross-sections of the cores of the connected wires, overall dimensions, and the maximum operating voltage of the network.

Clamps from other manufacturers may be labeled differently. Therefore, when buying, you need to check with the seller the parameters of the product based on the factory documentation. It should be noted that with different brands, the geometric dimensions of the clamps designed to connect the same sections are the same.

8 types of caps from an imported manufacturer

This type of connector is very popular in the West, from where it came to us. A wide range of models allows you to make most of the contacts of lighting and power wiring in this way.

Types of imported PPE:

1. Improved winglet design makes it easier and more comfortable to spin.
2. Uses clips of low profile design, shorter than standard length. Convenient for laying in small junction boxes, working in cramped conditions.
3. Modification of the previous model, equipped with wings that facilitate and enhance twisting.
4. PPE for twisting aluminum conductors with copper. The inside of the cap is filled with a special paste that prevents oxidation.
5. Connectors that protect contact from moisture. They are filled with silicone sealing paste, which prevents moisture from entering inside, preventing corrosion. At the entrance of the cap there is a split elastic cuff that holds the sealant. There is no need for additional sealing of the joint when making the connection outdoors or in wet rooms.
6. Clamp with a small hole in the top. The seemingly ridiculous design is needed for a twisted connection under the terminal. First, the end of a longer, cleaned core is released into the hole. After winding the clamp, the protruding wire brought out is looped under the terminal. It is very convenient to connect bonded ground wires to the case or terminal.

1. A connector where the wires are clamped not by a spring, but by a countersunk screw. Reminds the joint of our terminal block, which is placed in the PPE cap.

1. For sealing, you can use a special connector. It is a small plastic cup in which the completed PPE is placed. Silicone filling guarantees complete waterproofness and protection against moisture. Practically the wire can be put in water.

Proper twisting

It is easy to screw the PPE caps onto the pre-prepared ends of the cores. No special tools or fixtures are needed. Two ways:

1. No prerolling.
   1. the stripped cores are folded and aligned along the edge of the insulation;
   2. simultaneously or alternately by trimming the ends of the cores, their length is aligned. It should be equal to the depth of the housing opening (10-12 mm);
   3. holding the wires with one hand, with the other hand screw the cap clockwise until the spring is activated;
   4. twisting is completed by twisting the body to the stop with your hands or with a tool.
2. Fixation of pre-stranded conductors:
   1. stripped and aligned wires are tightly twisted and shortened to the desired length by trimming, the direction of twisting must coincide with the direction of rotation of the clamp;
   2. body is twisted.

The choice of method depends on the cross section of the conductors. Thin wires are best pre-twisted. There is an opinion that it is better to strip the strands during preliminary twisting a little longer than required by PPE. An increase in the number of turns will increase the density of contact by increasing the area of ​​contact of the cores. The exposed area is insulated with electrical tape or heat shrink tubing.

Twisting PPE should be neat, but as strong as possible. It must be firmly held on the twist. It cannot be torn off by hand with a pulling force along the axis of the wires. It is convenient to use PPE caps for connection, but you need to know and follow some rules:

• Use clamps appropriate for the cross section of the wires to be connected. Too small a hole diameter will not allow the entire bundle of wires to be inserted into it. Too big will not create a tight contact, will not fix the wires in the clamp. The twist will heat up, if it makes contact at all;
• Ensure tight twisting of wires. We must not allow the load current to flow through the metal of the spring, heating it. The loss of springiness will turn the PPE into a simple twist;
• It is forbidden to use PPE for connecting copper and aluminum wire. This is done in a different way.

Do not strip the insulation with pliers or wire cutters. If there is no special tool, carefully remove the insulation with a knife, avoiding damage to the surface of the core.

Pros and cons of the method

PPE caps offer many benefits to the electrician:

• No additional equipment or tools required. Easy and economical installation, no need for separate insulation;
• The case, made of non-combustible heat-resistant plastic, simultaneously provides three types of contact protection:
  • mechanical;
  • Electrical insulating:
  • Fire fighting.
• Compared to other connection methods, it is possible to:
  • Detachable joint;
  • Reusable connector.
• Legalization of twisted old wiring before or after inspection by a fire inspector. The boxes are opened, the old electrical tape is removed, new PPE is wound onto the twist. If the direction of the twist does not match the direction of rotation of the cap, it will have to be redone.

There are also disadvantages:

• The main one is the impossibility of connecting a stranded soft wire;
• Requires careful sizing.
• Not a sealed joint. It is unacceptable to perform for street wiring. Wrapping the junction together with the cap with electrical tape, to some extent, prevents the accumulation of moisture inside the case;
• Relatively large dimensions. PPE caps take up a lot of space inside the junction box.

Scope of application

PPE caps are used to create connections during the installation of electrical networks inside public and residential buildings and structures. Application in industrial, wet or chemically active environments, possible by placing the strands in protected junction boxes.

No. Installation with PPE twists involves connecting only copper wires. The connection of copper and aluminum wires in one twist is also prohibited. In fairness, it should be noted that two well-known global manufacturers have in their line one size each, specially designed for mounting aluminum wires. However, the design of such clamps is fundamentally different and, among other things, involves filling the body with an anti-oxidant paste. PPE is presented on the Russian market only for the installation of copper wires.

How many wires can be installed at the same time using PPE?

The number of wires cannot exceed the maximum possible total cross section specified in the specifications for each PPE size. In practice, the total cross section of the connected wires is usually less than the maximum possible total cross section. In general, if the installation takes place without preliminary twisting of the wires with the help of pliers, and the twisting occurs directly during the rotation and tightening of the PPE, then the optimal number of connected copper wires is 2–3. The maximum is 4. It all depends on the cross section of the wires connected by twisting. The larger the cross-section of the wires, the more time-consuming the installation is and the fewer wires can be connected in a twist.

Is it necessary to pre-twist the wires before installing and installing PPE?

For most sizes of PPE, this is not necessary. First of all, this applies to the entire range of PPE-K (KVT), which have a powerful lever in the form of special ledges (“wings”) that facilitate tightening and large sizes of PPE (N3, 4, 5). For installation without preliminary twisting, it is necessary to strip the wires and arrange their ends close to each other, so that they form an acute angle of the "pyramid". After that, put a PPE cap on them so that the ends of the wires go inside the spring cone and, slowly turning, twist clockwise until it stops. In this case, the wires will twist themselves from the force applied to the clamp body during rotation. Pre-twisting wires with pliers for solid wires is a violation of the correct technology. In addition to the fact that the sponges of the pliers disfigure the vein, the twist made with the help of the pliers will never have the shape of a regular, tightly curled and uniform “pigtail”. Next, for sure, you will need to trim the ends of the reins. And anyway, if the twisting has already been done “manually”, why do we need PPE? You can wrap the connection with electrical tape and consider the installation process complete.

Always bought standard PPE. What is the difference between the new SIZ-K?

Often, the installation of connecting insulating clamps requires a certain physical preparation. The force required when tightening the PPE is the greater, the larger the cross section of the wires to be mounted. If, when working with wires with a cross section of 1 or 1.5 mm², the installation progresses quickly, then when installing a power outlet group with single-core wires with a cross section of only 2.5 mm², twisting from 3 wires will seem an order of magnitude more laborious. And if the wiring needs to be carried out immediately in a dozen junction boxes, this can be a real test. This is where PPE comes in handy with their excellent ergonomics and increased leverage. There is no need for preliminary twisting of wires with pliers and installation time is reduced. Thanks to the special square profile of the clamping spring and the increased torque of SIZ-K, the quality and reliability of such a connection is beyond doubt. Indeed, often further tightening of PPE is impossible, not because there is not enough strength, but because the clamp body slips in the hand! In addition, PPE-K are more wide-ranging compared to budget PPE. This means that only one PPE-K standard size covers several ranges of budget PPE and can replace them. In general, take yellow and red PPE and PPE-K once in your hands (their min / max ranges are almost identical) and try to connect 3x2.5 single-core copper wires. All questions will disappear automatically, and the difference in price will seem not worthy of attention!

Is it possible to mount stranded and solid wires in one twist of PPE?

Can. The installation of flexible wires is somewhat different from the installation of solid wires and requires certain skills. When connecting flexible fine-stranded conductors, they must first be twisted “by hand” in order to give the connection a cone shape. Twisting must be done in the same direction in which PPE will be screwed - clockwise. If individual wires or wires protrude beyond the pyramidal contour of the twist, trim the tip of the twist with wire cutters or cable cutters. After that, the connection can be brought inside the PPE body and proceed to twisting clockwise.

Is it necessary to wrap the junction of the plastic case of the twist with wires with electrical tape after installing the PPE?

If the wire connection is stationary and vibration is not expected, there is no particular need for such a winding. Properly tightened twist will keep the connection even without electrical tape. If the stripping length was incorrectly calculated and the bare part of the wires comes out from under the cap, then it makes sense to use electrical tape. In general, tape winding is rather an additional insurance for fixing the twist and makes the connection splash and moisture resistant.

I always bought PPE manufactured by KBT. When there was a shortage of availability, I bought yellow and red PPE elsewhere. It turned out that the dimensions are completely different. Is there any standard?

Unfortunately, there is still no single generally accepted Russian standard for PPE. It also did not exist under the Soviet Union, despite the fact that even then attempts were made to produce caps with a built-in spring according to their own specifications. The current situation on the electrical market in Russia regarding insulating clamps (PPE) can be described in one word: "chaos". The only progress that has been achieved is the integration of the international system of size differences according to the body colors (as opposed to clips of the same color of the early post-Soviet period). Now on the market there are different manufacturers and importers with a standard color range: gray, blue, orange, yellow, red. However, this is where the similarity ends. Because the dimensions, mounting dimensions, and quality are completely different for everyone. Those. when purchasing orange PPE from another supplier, the buyer cannot be sure that he will be able to connect wires to them, which he previously successfully mounted with a similar orange clamp. Connecting insulating clamps (PPE) of the KBT trademark are produced according to factory specifications and are distinguished by dimensional stability, high quality workmanship and a manufacturer's warranty.

Do the connecting insulating clips "KBT" have flame suppression properties?

Both standard PPE and PPE-K manufactured by KVT are made of materials that suppress combustion and can be used for indoor wiring.

Is it possible to install PPE rolls outdoors?

Connecting insulating clamps (PPE) are designed for indoor installation (in junction boxes and electrical panels). The minimum degree of protection IP20 does not allow the use of PPE in outdoor outdoor installation.

What are the features and benefits of installation using PPE cable twists?

Perhaps the main reason for the popularity of insulating clamps (PPE) is that they repeat the traditional technology of twisting copper wires that has existed for a century and make installation faster and more civilized. The main purpose of PPE is to simplify the process of connecting two or more wires as much as possible. If we talk about the benefits, then it makes sense to compare the installation of PPE with ordinary twisting or crimping wires. There are several advantages of mounting with PPE: – Reduced mounting time. During the time spent on twisting, soldering and subsequent winding of wires with electrical tape or crimping one connection with a special tool, with the help of PPE, the installer can mount up to ten connections. – Connection isolation. After twisting, soldering or crimping wires, the resulting connections must be insulated somehow. Traditionally, this was done with electrical tape. When installing PPE, a strong and reliable insulating housing is already present in the design. Thus, no additional operations are necessary. – Safety and health. When mounting using PPE, unlike soldering, you should not be afraid of lead fumes and possible injuries from working with a soldering iron. – No need for special tools. Instead of a set of additional tools and accessories, you can limit yourself to only a good stripper for stripping insulation and PPE. - The price of the issue. Minimalism in the configuration of the mounting kit cannot but have a positive effect on the price.

What is the service life of PPE?

Properly selected and installed PPE, when used in normal mode, will last as long as the cable will be used. At the same time, the service life depends on the following main factors: – The quality of the PPE itself. If you want the connection to have proper mechanical strength, and during dismantling, the spring does not fall out of the body along with the twist, carefully choose the supplier. - Choosing the right PPE is half the battle. When choosing the size and type (with or without wings), pay attention to what sections it is designed for and take it “with a margin”. You should not reinvent the wheel and try to insert wires of large sections into a case designed for small sections. Nothing but an unreliable connection or damaged PPE will result. - Competent assembly and disassembly. If the installation is carried out according to the “rules”: without the formation of a preliminary twist with pliers and with a slow rotation of the body clockwise until it stops, and dismantling counterclockwise, then the PPE will respond to you with the same care and will last a long time. When installing flexible stranded wires, you should also calculate the forces in such a way that you do not overdo it and do not “roll the thread”.

How to choose the right PPE?

Properly selected and installed PPE, when used in normal mode, will last as long as the cable will be used. However, the service life depends on the following main factors: – Purchase the connecting insulating clips only from a trusted supplier. – Make sure you only connect copper wires. - Determine how many wires you are going to connect, and what is the total cross section of the bundle of wires. – Depending on the total cross section of the wires to be mounted, select the required type of connectors: SIZ or SIZ-K. In this case, choose the size "with a margin."

We have already reviewed the article: how to twist wires, but only old methods were considered there, which cannot be called safe and simple. For efficient and high-quality connection of wires, it is necessary to use PPE caps. In this article, we'll take a look at how to use PPE clips, look at the types, sizes, and key benefits of using them.

Design of PPE clips

The design of caps for connecting wires is considered very simple, it includes two components:

• The cap, it is made of plastic and shows electrical insulating properties. Plastic is not afraid of temperature changes and is even able to withstand a voltage of 600 V.
• Spring. As a rule, the spring has a conical shape, due to which the wires are clamped. The spring is made of steel, but other materials may be used in some situations. Additionally, the spring is treated with an electrochemical solution.

This is what the PPE cap looks like in the photo.

How to use

We will look at two methods of twisting wires using PPE:

• No pre-twisting.
• With pre-roll.

If it is necessary to connect two wires, they can be inserted into the spring with little effort. Then it is necessary to rotate them in a clockwise direction.

If you need to connect several wires, then initially they must initially be twisted together using the old methods, for this you can use ordinary pliers. After twisting, it is necessary to insert the wires into the PPE, see photo.

Remember! It is necessary to twist the wires until the contact connection is complete in order to ensure reliability. We twist only clockwise, during this process use force, it is she who will ensure a reliable connection for a long time.

Also remember that with the correct connection, it will not be necessary to additionally insulate the wires, since the caps do an excellent job with this task. However, here it is extremely important to choose the right size cap so that the wire is perfectly sized into it.

How to use PPE clearly you can see in the next video.

Connector classification

Often our subscribers ask the question: how to choose a cap? In fact, you should be careful here, but there is nothing complicated about it.

It is immediately worth highlighting that all PPE connectors are divided into two types:

1. Domestic.
2. European.

Their markings are the same, the only difference is the quality of workmanship.

PPE caps are labeled as follows:

If we talk about such a parameter as color, then there is not much point in paying attention to it. Only professional electricians are guided by color, who can determine the cross-section of wires at a glance. And remember that some manufacturers do not respect color coding.

Is it worth using: pros and cons

Initially, we highlight several reasons why you should use modern connectors:

1. Fairly low price.
2. Twisting wires with them is a pleasure.
3. On their body you can leave designations, for example: where is the phase or zero.
4. Safety is created and the likelihood of spontaneous combustion is minimal. Since the plastic connectors do not support combustion.

However, there are also several disadvantages:

• In many situations, it is not possible to make a strong fixation of the wires.
• In the caps, copper and aluminum wires cannot be connected to each other.

So we have examined what PPE connecting clips are. Finally, we recommend watching a few more videos on this topic.

And one more thing, but note there are a few errors here.

Purpose

Cap connecting electrical clamps (PPE) of spring type are designed to connect two or more cables / wires with copper conductors with a cross section of 0.5 to 10.0 mm 2 and insulate the connection. For each size of PPE, the manufacturer indicates the range (minimum and maximum) of the total cross section of the connected wires. This type of clips can be used repeatedly. Some manufacturers, to facilitate the selection of the clamp, make them in different colors - depending on the size.

Clamp design

PPE consists of a body and a core. The clamp body is made of flame retardant plastic (PVC, nylon, polypropylene). To facilitate the screwing of the cap during installation, the body has special ribs or protrusions.

The core of the cap is a cone-shaped metal spring. When the cap is screwed onto the strands, the spring compresses them, providing electrical contact.

Application area

These connecting clamps are used in the installation of electrical wiring in residential, public and industrial buildings and structures. It is not allowed to use PPE in explosive, chemically active and humid environments without junction (branch) boxes of the appropriate degree of protection.

PPE installation steps

The connection is ready to use.

Advantages and disadvantages

The main advantage of PPE of the “cap” type is the speed and ease of installation, since:

1. No additional tools or fixtures are required.
2. Additional isolation of the junction is not required, since the PPE body acts as an insulator.

Disadvantages of cap PPE:

1. It is necessary to choose the correct size of the clamp, otherwise the cap may fall off after installation.
2. Only copper conductors of wires and cables can be connected. It should be noted that there are also clip-caps of a special design (their distinguishing feature is that the body is filled with antioxidant paste) for connecting aluminum conductors, but they are rare.
3. They have an IP-20 degree of protection, so they cannot be used for outdoor outdoor installation.

During operation, any wires are subjected to stress and heat. Therefore, for a high-quality supply of an enterprise or a private house with current, a tight contact between the wires is necessary. This can be achieved by twisting PPE or connecting insulating clips. Shortly they are called caps because of their appearance.

Ways to combine wires

To assemble an electrical circuit, you need to ensure reliable contact between the cable cores. For this, several options are used:

• Plain or isolated twist.
• Use of welding or soldering iron.
• Use of screws and nuts.
• Through terminal blocks or blocks.
• Self-clamping elements such as Wago.
• Caps are insulating.

Plain twisting and soldering are the most popular of them. However, these methods are not without drawbacks. The first of them does not imply a rigid fixation of the wires, as a result of which the contact may weaken, there is a possibility of oxidation and destruction of the bundle. To make a connection in the second way, it is necessary to use special equipment, which may not be available at the installation site or its use will be inconvenient.

In addition, according to the Electrical Installation Rules (PUE), it is forbidden to connect wires using twists. In emergency situations, there may not be enough time to prepare welding or soldering equipment. Therefore, it is necessary to provide alternative options that meet the rules and regulations.

Use of caps

Such a method does not require special skills and the use of additional devices from the employee. In addition, the speed of creating a connection with this method is quite high in order to carry out prompt installation work. The PUE allows the use of electrical PPE in various installations.

Purpose of the device

Such clamps are of the spring type and are designed to mate two or more conductors with the necessary contact and reliable insulation. Despite the fact that the Rules do not clearly regulate the operation of such devices, GOST 50043 .1-92 establishes their compliance with safety requirements.

Some electricians talk about cases from practice where PPE caps did not work well. However, there are explanations for this:

• Insufficient qualification of the installer himself.
• The use of low-quality products of dubious origin.
• Incorrect calculation of the wire cross-section relative to the load on the power grid.

If all work is carried out according to the instructions using high-quality materials of appropriate sizes, then when the line is protected using circuit breakers, such connections will last a long time without additional service.

The use of such clamps is possible not only in residential premises, but also in production. However, in places with a chemically active environment, high humidity, it is necessary to place the structure in junction boxes of the appropriate degree of protection.

Do not use electrical PPE when connecting conductors of dissimilar metals. Of particular note are copper and aluminum conductors. During heating, galvanic processes occur between them. destroying the contact density. In this case, it is advisable to adopt steel transition terminals treated with a conductive compound.

Design

These connectors are designed for multiple use. They are made very simply. Any PPE insulating cap for twisting wires consists of a body and a spring. The first is made of plastic that does not support combustion. It can be nylon, PVC, polypropylene. For ease of handling the clamp, its surface is ribbed or with special notches. The shell performs a protective and insulating function.

A metal crimp spring acts as a core. It has a conical shape. While winding the cap onto the twist, it is tightened, providing reliable contact.

The dimensions of the spiral deserve special attention. In order to choose the right cap, you need to know the cross section of the wires to be connected and the smallest base of the cone in which their contact will be created. If the wire is thinner, then it will not be possible to compress it, and the thick one simply will not fit in the cap.

To put the crimp on the twist, you need to press it harder to push the coils of the spring apart. Rotate the body in a clockwise direction. By following these simple manipulations, you can create a tight cable connection.

Product classification

There are many soldering caps for soldering conductors of various manufacturers on the Russian market. Domestic standards provide for the following sizes similar electrical products:

It should be noted that such names correspond to products of domestic manufacturers. Imported caps, despite the similarity of designations, are slightly smaller. Therefore, when buying, you should carefully read the labels on the package.

Method of work with PPE

The main requirement for manipulations with caps and wires is their size. The quality of contact depends primarily on this. In order to make the right choice, it is necessary to add up the sections of the cores planned for twisting and select the required fixture from the table. It is necessary to focus not on the extreme values ​​\u200b\u200bof the indicators, but on the average ones. In this case, the tightest possible contact is ensured.

The choice of method depends on the thickness of the wire. Thin, for example, half a square, it will not be difficult to connect, but more powerful, 2.5 square millimeters, put a high load on the spring and often break it.

Stranding length

Manufacturers recommend stripping equal to the depth of the cap or slightly less. This will be approximately 10-12 millimeters. Longer tips do not seem to affect the quality of the pairing, but this should be done with a large number of wires to be connected. If the size of the bare part is small, then it will not be possible to create the desired contact area for all participants in the twist.

If a bare part of the wires peeks out from under the clamp body, then it should be wrapped with electrical tape. And although the name of the PPE in this case will not be entirely correct, the reliability of the pairing is ensured by the cap, the wires will not weaken when heated under load.

Advantages and disadvantages

Insulating devices have a main positive feature in their application. It consists in the fact that due to the plastic case, they perform three functions at once:

• Electrical isolation.
• Fire protection.
• Resistance to mechanical damage.

It is also important that, unlike sleeves and tips, PPE can be easily turned counterclockwise and reused. It is possible to correct an erroneous connection without changing the length of the wire. This quality is widely used in the arrangement of temporary huts or the connection of portable electrical equipment.

A lot of firefighters' complaints are caused by twists in junction boxes on power lines. Caps solve this problem. Simply open the branch, remove the old insulation and screw on the cap. Such a connection will not cause remarks by the checking inspector.

One of the main disadvantages of such products was the impossibility of their use with stranded wires. This mounting method is prohibited. It is also not recommended to splice aluminum conductors. Some manufacturers on the packaging directly indicate that the scope of their products is copper cables.

Causes criticism and tightness of such a twist. In conditions of high humidity, the spring rusts and becomes unusable, destroying the contact between the cores. This problem can be partially solved with the help of electrical tape.

Another inconvenience is related to the size of the product. With a large number of wires, not every junction box can accommodate several caps. However, due to the convenience and ease of installation, cost-effectiveness and durability of the connection method, many go to replace the distributor.

Clamp analogues

The main competitors of such devices are terminal blocks. In this case, two wires are tightened by means of a screw. However, this method has several disadvantages, among which there is a weakening of the contact, which requires constant monitoring and periodic tightening. If the device is in an inconvenient place or their number is large, then it is very costly both in terms of effort and time.

Another weak point of such connectors is the block material. There are many Chinese products made from cheap polyethylene on the market. It does not withstand even light heat and melts or ignites, which can lead to a fire. Therefore, the use of PPE caps is fully justified both at home and at the factory.