How to cut threads on a pipe

Threading a water pipe: tools, preparation and methods

Installation of a water supply system requires the assembly of individual elements into a single system. Metal pipes and shut-off valves are joined with a threaded connection. The method ensures a strong and tight connection. To install communications yourself, you will need tools for cutting threads on water pipes.

Types of threads on pipes

A thread is an alternation of projections and depressions on a surface located along a helical line. It can be external and internal, left and right. Common types:

• cylindrical pipe;
• pipe conical;
• inch cylindrical (US standard);
• round;
• inch.

In plumbing installation work, the first two types are usually used. They are used to connect water fittings:

• Cylindrical (G) – the profile is represented by an isosceles triangle with an apex of 55°. The protrusions and depressions are rounded. Recommended for pipes up to 6 inches in diameter.
• Conical (R) - the thread has a triangular profile, forms a taper of 1:16, and is characterized by high tightness of the connection of parts.

Pipe threads can be inch or metric, respectively, measured in inches and millimeters.

Required Tools

To complete the work you will need threading tools:

• A die or blade is a device in the form of a nut made of hardened metal, which has pointed cutting edges (cutters). They are round, square and hexagonal in shape. Types of dies: solid, sliding, split. Holes are provided to remove chips.
• Klupp is a tool based on a sliding die. The two-part body allows you to adjust the cutting diameter. A handle is provided for ease of use. Some models are equipped with a ratchet that allows you to perform rotational movements with one hand. The professional tool is equipped with an electric drive.
• A tap is a hardened steel screw with cutting edges. Consists of a working part and a shank. The set includes devices for roughing and finishing work.

Additionally prepare auxiliary devices:

• tape measure and pencil - for measurements and marks;
• caliper - determines the diameter of pipes and fixtures.

The tools used must be of high quality, the metal of the cutters must be sharp and durable. When working with dies and taps, you will need a vice.

Preparing for work

The area where you will have to work with a thread-cutting device for water pipes is cleaned of rust, dirt, and paint residues. Sandpaper is used. The surface should be cleaned to a metallic shine. The end surface is chamfered. It is necessary to prepare a lubricant for processing the pipe and cutting tool. You will need a rag to clean the shavings.

Methods for cutting threads on a water pipe

Cutting methods are divided into two types: manual and automatic. In the first case, you will need a set of thread-cutting devices. Dies are used for cutting external threads, and taps are used for internal threads. Tool sizes are determined using reference tables. Automatic cutting occurs on machines or power tools. The method is accurate and suitable for pipes of any diameter. The machines perform milling and thread rolling.

Die cutting

The choice of tool type depends on the quality requirements. The best result is achieved when using a solid die, which has high rigidity. The disadvantage of the device is rapid wear. Spring-loaded dies (with a cut in one of the axial holes) allow you to change the thread diameter within 0.3 mm. Their rigidity is reduced, the incisors last longer, but the purity of the threads is lost.

The prepared pipe is clamped in a vice. The die is placed in the holder and secured with screws. Lubricant is applied to the treated area and cutters. The tool is placed on the pipe at a right angle. Rotation occurs smoothly, clockwise. After making several turns, the chips are removed and lubrication is restored. For high-quality cutting, a finishing die is used after the roughing die. The finished thread is cleaned with a rag.

Using the Clupp

Using a pipe clamp is more convenient than using dies. The tool is more expensive, but for doing a large amount of work it is better to choose it. The clamp gives a clean turn, the sliding design allows you to adjust the thread diameter.

Installing guides reduces the risk of distortions and facilitates the cutting process. If the design includes a ratchet, a ratchet wheel is placed near the die. When it turns, the tool head moves.

The ratchet is indispensable in cramped working conditions.

The pipe is clamped in a vice, leaving a small section. The short protruding part will not allow the metal to bend from the applied forces. The pipe and cutters are lubricated with machine oil. The protruding part is inserted into the die guide. Cutting occurs with short rotational movements. It is periodically rotated back to cut off chips. Lubricant is added during operation. When cutting threads on water pipes, it is important to monitor the number of turns.

Using an electric tool allows you to cut in a few seconds. Replaceable heads with cutters are selected to match the required pipe diameter. The work is not only fast, but also of high quality.

Working as a tapper

Internal threads are made with a tap. Its diameter should be slightly larger than the pipe. When working, it is recommended to use a set of two or three parts. They perform rough and finishing cuts. The first tool does the main work, removing up to 70% of the chips. The finishing tap has a small chamfer and a full cutting profile. Tools are distinguished by grooves on the shank:

• one is black;
• two – average;
• three – finishing.

The inside of the pipe requires cleaning and lubrication. The tap is inserted vertically, the shank is secured in the driver. Rotation is clockwise. When working with soft metal, the tool is periodically turned out and the chips are cleaned out. Lubricant must be used. After completion of the work, the quality of the thread is checked.

Main reasons for marriage

The cause of defects in work is the inattention of the worker or the use of low-quality tools. Common pipe cutting defects when working with a tap or die:

• Torn threads - a problem occurs when using a dull die, untimely removal of chips, or insufficient lubrication.
• Incomplete thread - the diameter of the thread hole exceeds the recommended one.
• Skewed helical grooves – incorrect installation of the die or tap.
• Thread failure is caused by clogging of the grooves with chips, poor quality of the tool, or the pipe diameter is larger than specified.
• Tap failure - excessive force applied in a narrow hole, insufficient chip removal, lack of lubrication.

Self-preparation of parts for threaded connections is quite accessible if you have the tools. In order for the work to be done efficiently, you must follow the rules. The use of sharp tools and accuracy compensate for the lack of professional skills.

Source: https://StrojDvor.ru/vodosnabzhenie/narezka-rezby-na-vodoprovodnoj-trube/

How to cut threads on a pipe

Independent thread cutting on pipes of various classes requires the performer to have certain skills and knowledge of all the intricacies of this procedure. In this article we want to introduce you to how to cut threads on a pipe with your own hands (on a water pipe, on a stainless pipe).

Mastering the technique of thread cutting will allow you to independently repair water supply and heating networks, as well as any household appliances that include pipe products.

Threading techniques

Manual thread cutting

The technique of cutting threads on pipe blanks involves the use of the following techniques:

• use of special threaded combs and cutters;
• rolling threads using round (flat) dies;
• preparing a threaded connection using “classic” taps and dies;
• thread cutting using special cutters.

Thus, preparing threaded connections at home is possible only if you have certain devices and tools. In the article we bring to your attention, we will consider in detail the method of cutting threads using a special thread-cutting kit (the so-called “klupp”).

Tool composition

Manual die set

What tool is used to cut external threads? An electromechanical thread-cutting kit called a die is used in conjunction with a set of radial dies of various diameters designed for cutting threads on pipe blanks of any size. In addition to the device itself, you will need the following tools and materials for threading:

1. Taps for quick cutting of internal threads.
2. A mechanical vice used to hold pipe workpieces.
3. A grinding machine designed for preparing thread cutting areas.
4. Lubricating oils.

We immediately draw your attention to the fact that working with an electric grinder is only allowed with gloves and safety glasses.

The procedure for cutting external threads on a water pipe

Making carvings

First of all, using a grinding machine, a part of the water pipe with an old thread or a section damaged by corrosion is cut off.

To form a high-quality cut, guaranteeing the convenience of all subsequent operations, immediately after marking, the pipe section is firmly fixed using a gas wrench or clamped in a vice. Next, a thin chamfer is cut off on the prepared section of the pipe, which significantly facilitates the rotation of the die. To facilitate its sliding along the thread, the cutting area is lubricated with machine oil.

During the threading process, the die holder rotates clockwise; but after the formation of several threads, the direction of its rotation is reversed. Using this technique allows you to free the working area from waste metal shavings.

Thread cutting on riser

The length of the threaded connection should not exceed 1 cm, which corresponds to the standard for most household pipeline networks. At the end of the thread cutting procedure, the treated area is cleared of metal shavings and then thoroughly wiped with a rag or rag.

Threading of internal threaded connection

Internal thread cutting

Before cutting threads on the pipe in its internal cavity, you will need to measure the diameter of the pipe hole. Based on the data obtained, you can select a working tool (tap) of the required size. Make sure that the length of the pipe section protruding from the wall is several millimeters longer than the threaded part being cut.

Once you have finally decided on the required diameter of the internal hole, you should drill it to a size convenient for cutting threads.

During the drilling process, you need to carefully monitor the position of the inserted part of the drill, which should not deviate from the vertical.

Upon completion of the preparatory operations, a tap of the required diameter is inserted into the pipe hole while simultaneously rotating its base clockwise. Rotation is carried out using the so-called “wrench” included in the tool kit.

The procedure for preparing internal pipe threads involves the use of the following working tool:

• tap under the designation No. 1, intended for preliminary (rough) “running” of threads. The design of this tap is such that when using it, up to 70% of the material is removed;
• tap No. 2, used for final (finishing) thread cutting. With its help, the remaining 30% of the pipe material is cut off.

Thus, to obtain a high-quality and complete thread, you will first have to “walk” through the internal cavity of the pipe with tap No. 1, and then repeat the same operation using tap No. 2. All of the above work must be accompanied by the introduction of small portions of machine oil into the work area.

Near the wall

The principle of thread cutting is no different from the usual situations described above. The only difference is that it is extremely inconvenient and problematic to perform this work near the wall. For example, sometimes it is necessary to slightly hollow out a section of the wall near a pipe.

It is very important to make the cut carefully. If it is uneven, it will be difficult to cut, and considering that you have already made a recess in the wall, cutting the thread will be extremely difficult. You can use a die to complete this task.

First lubricate the pipe and die, and then start cutting the branches.

If the pipe near the wall has a large diameter, then the task of cutting threads becomes more complicated. In such circumstances, it is necessary to use not a die, but a die. For convenience, it is better to use an electric socket.

On a stainless pipe

As for cutting threads on a stainless pipe, the task is complicated by the fact that the metal used is quite hard. Therefore, for cutting, you should select the appropriate grade of steel dies. In this case, marking P18, or better yet P18F2, would be a suitable option. The letter “F” means that the material contains a regulating additive of vanadium up to 2%. In addition, dies marked P9 can be used to cut threads on a stainless pipe.

If you choose a die of the wrong brand, you may end up without a die and without a thread. In some cases, it is only possible to make a thread on the shaft with a cutter.

Instructions for cutting threads with a die:

Source: https://kakpravilnosdelat.ru/kak-narezat-rezbu-na-trube/

How to cut a thread on a pipe near a wall - Here is Master - a site for masters

Independent thread cutting on pipes of various classes requires the performer to have certain skills and knowledge of all the intricacies of this procedure. In this article we want to introduce you to how to cut threads on a pipe with your own hands (on a water pipe, on a stainless pipe).

Mastering the technique of thread cutting will allow you to independently repair water supply and heating networks, as well as any household appliances that include pipe products.

How to cut a thread on a pipe near a wall? — Metals, equipment, instructions

The answer to the question of how to cut a thread on a pipe is not as complicated as it seems at first glance - it can be solved exclusively by brute force and common sense, which every professional craftsman should be able to use. This master class from the site stroisovety.org will reveal to novice specialists all the subtleties and nuances of cutting pipe threads using a manual machine.

Threading machine photo

How to cut threads on a pipe: preparing a pipe cut

The thread cutting process begins from the very moment when you first touch the angle grinder to the pipe being cut - if you do not know how to cut smoothly, you will have to fiddle with the edge alignment for a long time.

The fact is that it is quite difficult to screw anything onto the thread cut on the beveled end of the pipe. Therefore, this must be taken care of at the stage of cutting out the pipeline.

In this regard, no one will help you, and you will have to learn to cut smoothly with a grinder on your own.

How to cut threads on a pipe with your own hands photo

The next nuance that cannot be ignored when answering the question of how to properly cut a thread on a pipe is chamfering, without which it will also be difficult to screw fittings or shut-off valves onto the finished thread.

The chamfer is removed with a small grinder - the pipe is simply sharpened so that its edge is at an angle of approximately 45˚. You can do it a little more or a little less - it doesn’t matter, the main thing is that the future thread has a high-quality start.

How to chamfer a pipe photo

We should also talk about the condition of the pipe itself. As a rule, thread cutting is done in places where the steel pipe tends to rot most quickly. Near the floor, ceiling and welds, steel is very susceptible to corrosion.

The pipe should be examined, and if the thickness of its walls is too small, then it is better to refuse threading in this place. The fact is that by cutting metal with a sharpening tool, you will weaken the steel even more, and it will rot very, very quickly.

But let’s return to the immediate answer to the question of how to cut a thread on a pipe with a die or, as it is also called, a die.

Do-it-yourself pipe threading technology

To ensure the best movement of a thread-cutting tool on hard metal, the pipe must first be lubricated - any lubricant is great for these purposes. A classic of the genre in this regard is lard. Yes, yes, you heard right! But by and large, sunflower oil is also suitable.

Now we put a machine on the end of the pipe and adjust the ratchet so that it returns freely counterclockwise. When everything is ready and the machine is set up, we slowly begin to cut. For the process to start, you need to apply a little pressure on the stem towards the pipe - you don’t need to press all the time. When the blade bites the metal and the cutting process is in full swing, there will be no need for this pressure.

How to cut a thread correctly photo

The cutting process itself must be carried out in stages. You need to proceed like this - first we cut one turn of thread, then we rearrange the ratchet and turn the ratchet in the opposite direction to chop off the chips. If this is not done, then in order to cut a thread on a water pipe, you will have to put in a lot of effort. This is how pipe threads are cut, step by step.

Ratchet for thread cutting photo

Ask how long to cut? I’ll tell you straight - all the teeth of the lerka should be on the pipe. Why? Everything is simple here - the thread cutting tool is made in such a way that each subsequent turn cuts the metal to a certain depth.

In order to obtain a full-fledged thread, so to speak, completely cut, all the teeth of the thread must take part in the thread cutting process, without exception.

In general, if you roll half a centimeter of thread, then you will not fully screw the fitting onto it.

How to cut threads on a water pipe with your own hands photo

When the thread is completely cut, the ratchet switches to reverse and is screwed off the pipe. Be sure to check how the fitting or tap is screwed onto the freshly rolled thread. In general, the final solution to the question of how to cut a thread with a die requires a high-quality check of it.

Well, concluding the topic of how to cut a thread on a pipe, I would like to give a couple of tips: firstly, during the cutting process, the pipe must be properly held with an adjustable wrench so that the riser does not turn and break in the ceiling; secondly, do not try to cut the thread too low to the floor - you won’t succeed anyway (if such a need arises, it is better to negotiate with your neighbors and make a cut close to the floor or ceiling).

Author of the article Alexander Kulikov

Source: https://spb-metalloobrabotka.com/kak-narezat-rezbu-na-trube-vozle-steny/

Pipe threading: available methods and methods of their application

Currently, pipelines can be assembled from plastic or metal pipes. Plastic pipes are mainly connected by welding, for which a special apparatus is used. Metal pipes are connected with threaded fittings. The joint of pipes with a threaded connection is as strong as possible. However, to assemble a metal pipeline, threading on the pipe is required, the application methods of which are described in this article.

A section of pipe with a self-made thread for further assembly of the pipeline

Tools used for thread cutting

Before starting work, it is necessary to prepare a tool for cutting threads on pipes, which includes the following devices:

1. tape measure, pencil and caliper. The pipeline is assembled according to a previously prepared diagram. At the first stage, it is necessary to prepare pipes of a certain length indicated in the diagram. A tape measure and pencil are used for marking. Vernier calipers are used to measure the diameter of pipes and select the required tool;

Tape measure and calipers for measuring pipes

1. Bulgarian. The tool is used to cut pipes according to previously applied markings. Instead of a grinder, you can use a hacksaw;

Metal pipe cutting tool

1. vice. Threading on pipes must be done clearly horizontally. To do this, the pipe section must be securely fixed;

Device for fixing a pipe in a certain position

1. machine oil and any other lubricant. Cutting threads on pipes by hand will be much easier if the tool and the end of the pipe are lubricated with special products;
2. glasses for eye protection. Any work must be carried out in compliance with all safety rules. When cutting threads, metal shavings can get into your eyes and cause severe damage, so protection in the form of glasses is necessary;
3. tool for cutting threads on pipes. This can be one of three options:

A set of dies for cutting threads of different sizes

1. • a set of dies and a die holder;

Set of dies and die holder

Internal Threading Tools

Preparation

Before cutting a thread on a pipe with your own hands , it is necessary to carry out a number of preparatory work:

1. cut a piece of pipe to the desired size. If any section of the pipeline is being replaced, then it is necessary to carefully cut out the pipe that has become unusable;

1. the section of the pipe where the thread will be cut is cleaned of paint, rust, and so on. All foreign deposits interfere with the work;
2. a chamfer is removed from the end of the pipe to facilitate the operation of the die.

The initial stage of threading

We cut the external thread with a clamp

Threading on a pipe with a die is carried out as follows:

1. a die of the appropriate diameter is selected. To correctly select equipment, a caliper is used;
2. the inner surface of the die and the prepared section of the pipe are treated with machine oil;
3. The die is inserted into a metal pipe, which makes it easier to rotate. The holder is included in the kit for cutting threads on pipes;
4. If the initial assembly of the pipeline occurs, the pipe is fixed in a vice. If you need to cut a thread on a water pipe during the reconstruction of a water supply system or other engineering system, you can make the thread directly on the installed pipe;
5. The die is installed on the prepared pipe and its rotation begins, that is, the thread cutting process.

Making threads using a clamp

After finishing cutting, the oil must be completely removed.

You can clearly see the process of cutting threads with a die in the video.

Thread cutting with a die

A die for cutting threads on pipes can be:

• round shape. To apply threads to pipes of various diameters, dies of different sizes are used;
• sliding The use of such a die helps in cutting threads on pipes of various diameters. A special holder is used for the sliding die.

Various thread dies

Dies for threading pipes are used more often because they are less expensive.

Before cutting a thread on a pipe with a die, you need to prepare the pipe in the manner described above. Then you can carry out the procedure itself according to the following scheme:

1. using a caliper, select the required die diameter;
2. lubricate the inside of the tank and the surface of the pipe with any available material;
3. secure the die in a special holder. Pipe tapping tools must be firmly secured in the holder. Otherwise, the thread will turn out uneven, which will lead to the formation of a leak at the connection;
4. The die holder rotates in the desired direction. After several turns, it is necessary, as in the previous case, to get rid of the accumulated chips. To do this, the tool is turned slightly in the opposite direction;
5. After threading, the pipe and the tool used are cleaned of grease.

Applying carvings using a ruler

To make an internal thread, you need:

1. prepare the hole. It must be clean and free of any coatings or foreign deposits. The hole is lubricated;
2. select a tap according to the diameter;
3. install the tap in the hole, while maintaining the verticality of the cutting equipment. Start rotating the tap clockwise.

Procedure for cutting threads inside a pipe

You can make carvings on a metal pipe yourself. This will require the purchase of a special tool and a small amount of time. The work is accessible not only to professionals, but also to ordinary users.

Source: https://vse-o-trubah.ru/narezka-rezbu-na-trube.html

Methods for cutting threads on a pipe and tools

Having a personal home in our time is a great success. It does not matter whether it is an apartment or a private house. In any case, the owner feels solid ground and confidence in the future. As a rule, in your own home you have to do a lot of work yourself. Well, for this you definitely need to have a personal instrument.

Very often, owners of private houses are faced with the creation of gas and water pipes. It should be noted that this procedure requires not only skills in working with a welding machine. Very often it is necessary to create detachable connections for further disassembly of communications when repairing and replacing certain elements.

But how to cut threads on a pipe? Today we will try to give a full answer to this question.

What is cutting called?

Before considering methods and tools, let's figure out what this process is called. Cutting is the special mechanical processing of workpieces in order to obtain cuts on the outside or inside. The result of the process itself consists of protrusions-coils and special grooves, twisted into a spiral, and alternating with each other.

Pipe thread

Depending on where the threads are cut on the pipe, different tools are used. This process is performed on the following elements:

• nuts;
• bolts;
• pipelines with a detachable type of connection;
• parts of various equipment and mechanisms.

In turn, cutting can be internal and external. In this case, as is already clear, different tools and devices are used. Let's look at all the techniques in as much detail as possible, and start with the technique for creating an internal view.

Internal view

You need to cut the internal thread on a pipe with a special rod called a tap. It, in turn, is inserted into a special knob. The tap consists of a front (intake) part, which is located at its end, a calibrating part (the middle of the head) and a tail with a square profile for normal retention in the device.

It must be said that when converting from the metric system to the imperial system, three types of taps must be used, which cut at different depths.

The technology for cutting internal threads involves the following sequence:

1. The tap must be selected according to the cutting pitch on the element that will be screwed into the pipe.
2. Next, the tap is inserted into the driver;
3. The tap is positioned strictly along the longitudinal axis of the pipe so that everything is cut evenly and without bevels;
4. Squeezing the cutting element and the end of the tap together, you need to turn the knob;
5. Cutting is done to the marked depth with a small margin.

Internal thread

The process itself is much better performed on a machine, where the tap is inserted into a three-jaw chuck, and the element in which the cutting will be performed is fixed on a movable bed. This ensures exact alignment of the axes. Doing this manually is much more difficult. But, if the connection is not very responsible, then you don’t have to bother.

External type

External threads are created on bolts, rods and screws using a die. This is a special device in the form of a washer that has a hole in the middle. Dies are divided depending on their design into:

• solid;
• sliding;
• prismatic;
• round.

Solid devices are washers with a constant diameter, and they cannot be disassembled. Those. For each rod size you need to use different devices.

Sliding types, unlike solid ones, can be used with small changes in the diameter of the rod. At the same time, they are fastened in a clamp so that all the numbers on the parts fully correspond to the numbers on the frame itself. Also, a special plate is placed between the stop and the die, which prevents the housing from cracking from pressure.

Prismatic types are used when cutting on 32 pipes and other common diameters. They consist of two detachable parts, on which there are grooves on the outer sides.

The round die is installed in an easy-to-hold wrench and may have one or more special places for stop screws.

The most practical among these types is the sliding type. Due to the ability to change the internal diameter, it can cut on a wide variety of elements that do not exceed the general cross-sectional size.

It is advisable to say that cutting on a stainless pipe is quite difficult, since this type of steel has high hardness. Other metals can be easily processed by hand, which saves time and money.

What thread should I use?

When creating a detachable connection for water and gas communication elements, cylindrical pipe threads are used. As a transition element between them, special bends are used, which have an internal thread.

The last two turns, which are cut on the elements, are called runaway. They allow you to wedge the coupling in such a way that a rigid and durable connection is obtained, and using sealing material you can achieve complete tightness.

A long type of cylindrical thread is most often cut on a gas pipe. The reason for this is frequent leaks through leaks and at the same time they are not visible to the naked eye. Water communications, unlike gas ones, can have a short cut type. It is also very widely used on large diameter elements to reduce the time required for twisting and cutting.

There are also cases when the turns are not cut, but rolled. This method is used in thin-walled communications for gas supply and heating systems. In this case, the critical wall size is allowed to be significantly smaller than when cutting.

Threads were cut into the pipe

Tools used

Today, the following types of clamps are used for external threads:

• pipe (usual type);
• Maevsky's clamps;
• ratchet

Conventional clamps are used when creating coils with your own hands. They are also used for small volumes of work performed. When cutting, sliding and non-sliding dies are used.

Pipe fittings are manufactured in two types:

• for diameters from 15 to 20 mm;
• for diameters above 25 mm.

The instructions for cutting with pipe clamps are as follows:

1. First you need to clamp the pipe in a vice, or clamps.
2. Next, its end must be cleaned of rust and other contaminants.
3. The cleaned end is lubricated with drying oil.
4. Next, a clamp is put on the pipe and, using blows with a mallet, it is seated in place.
5. Once you are sure of the correct location, you can begin rotating to cut grooves to the required limit.

You can also often find such a device as Mayevsky clamps when creating coils. Dies for it are produced in two versions: No. 1 (15 and 20 mm) and No. 2 (25 and 32 mm). For other diameters, it is best to use the usual, above-mentioned clamps.

Among the advantages of Mayevsky's die, it is fashionable to highlight light weight, simplicity of design, ease of maintenance and the ability to hot-swappable dies. It should be noted the importance of accurately installing them in accordance with the marks.

Threading tools

The ratchet type of this tool is used for element diameters of 15, 20 and 25 mm. For maximum convenient use, such devices use a ratcheting mechanism, which allows cutting on elements that are located in hard-to-reach places. With a diameter of less than 25 mm, everything is done in one pass. In other cases, a double pass is required.

Features of care

When using screws when cutting threads yourself, you must carry out proper care of this tool. So, upon completion of the work performed, they need to be disassembled and completely cleaned of chips and other unwanted contaminants. Next, it is recommended to lubricate the entire body with mineral oil so that rust does not appear on it and the rubbing parts “stick” to each other.

A prerequisite is to clean the instrument from dust and dried oil approximately once every 2-3 weeks, so that in the future the instrument does not crunch when used. To perform this procedure, experts recommend using the following technique:

1. Using a rag, everything is cleaned of visible contaminants that appeared while it was lying there.
2. Next, a caustic soda solution is made. The proportions are taken as follows: for one ten-liter bucket of warm water, 0.5 kilograms of dry matter is calculated.
3. Before washing, you should completely disassemble the instrument.
4. After the procedure, all parts are lubricated with oil and collected in a pile. It is advisable to then wrap the instrument in a rag or polyethylene to further protect it from contaminants.

Clips with dies should be stored in a dry place and closed. A small layer of lubricant will reliably protect the metal from rust and significantly extend its life.

To summarize and figure out how to cut a thread on a pipe, we can say that this procedure is performed using taps and dies. The first ones have no types and are selected separately for each internal diameter of the pipe. Dies can be either standard sizes, without the ability to change the diameter of the threaded hole, or with interchangeable values. Everything here depends on the type and type.

With the help of special devices called clamps, the cutting process can be significantly simplified. But, for normal operation, mandatory care is required for all instruments. They must be clean, lubricated and always ready for use. To do this, it is recommended to carry out prophylaxis once every 2-3 weeks.

Source: https://aqua-sovet.ru/truby/kak-narezat-rezbu-na-trube.html

Thread cutting methods

The technology of the pipe threading process includes various methods:

• the use of special threaded dies and cutters;
• knurling using flat or round dies;
• use of threading heads, taps or dies;
• milling with special cutters.

Accordingly, the thread cutting process requires the presence of special tools and devices. In this material we will step by step consider the method of cutting threads with a die - a special thread-cutting kit.

Tool composition

A die is a special device for cutting threads, equipped with several sets of cutting radial dies. They have different diameters, suitable for a particular sewer or water pipe.

In addition to the clamp you will need:

• a set of taps for cutting internal threads;
• gas wrench or vice for fixing the pipe;
• machine oil or any other;
• grinding machine for metal processing with a cutting disc.

Note! When working with a grinder, you need to protect your eyes and hands with special glasses and gloves.

Sequence of operations when cutting external threads

First you need to make sure that the pipe is in good condition and will not break when threading. If the pipe is painted, then it must be stripped of the paint layer.

We mark the place of the cut on the pipe and use a grinder to cut off the unnecessary piece of pipe perpendicularly, having previously fixed it with a vice or a gas wrench.
A chamfer is cut off at the edge of the pipe - this will simplify the process of screwing on the die. It is better to lubricate the place of the future thread and the teeth of the die with oil, or at least regular lard, for easy sliding. Next, we proceed directly to cutting the thread.

Usually two dies are used - a through dies, or a roughing one, the cutters of which only form the profile and a finishing one, cutting the thread directly. This, firstly, facilitates the cutting process itself, and secondly, reduces wear on the tool itself. We press the die holder with the pass-through die attached to it with force against the pipe so that an engagement is created.

Then rotate the holder clockwise. After making several turns, usually five turns, we change the direction of rotation to the opposite, turn half a turn back to clear the threaded groove from chips. The chips will break off and it will be easier to cut, then turn clockwise again.

It will be correct to cut the first thread with a guide bushing so that the thread does not become skewed. The bushing must have an internal diameter that matches the external diameter of the thread being cut. A die holder can be used to secure it. This improvement will ensure that the threads are aligned with the pipe.

Next, we begin to work with the finishing die, not forgetting to first lubricate its teeth. For greater force, you can lengthen the handle of the holder. It is very important not to try to do all the work in one pass. You need to move half a turn, gradually. Otherwise, you can bend the pipe and break the die.

You should not cut threads longer than 1 cm: this is the length of the threads of most elements of household water supply networks. At the end of the process, the freshly cut thread must be cleaned of chips and wiped of oil.

Internal thread cutting

This thread is cut with a tap. To select it, you need to know the exact size of the thread hole. If it is blind, then its length should be several millimeters longer than the required thread.

The hole is pre-drilled with a drill to remove the excess layer of metal and facilitate threading. It is better to select the required diameter using reference tables. But, you can make a rough calculation: it should be equal to the difference between the thread diameter and its pitch.

Then the cutting itself is performed directly in two passes: first, about 70% of the chips are removed with a rough tap, then with a finishing tap, the remaining 30%. The rotation of the taps is carried out clockwise using a “wrench” - a special tool for holding them.

Before operation, the taps must be lubricated with machine oil.

In this way, you can independently obtain a high-quality threaded fitting.

Source: https://positroika-doma.ru/inzhenernye-sistemy/kak-narezat-rezbu-na-trube

How to properly cut threads on a pipe using different tools

Threading is the process of machining a hole or rod in a part, during which a specialized thread cutting tool is used to obtain an external or internal screw thread consisting of helical protrusions and alternating spiral grooves.

Threading is done on bolts, nuts and pipes used in split piping systems and other structural parts.
If the pipeline is installed manually from pipes that do not have threads, then it will be important for you to understand how you can cut threads on the product yourself. The main characteristics of any thread are its depth, pitch, profile angle, profile, average, outer and inner diameters.

Required Thread Information

The thread profile is the cross-sectional figure near the thread. Depending on this indicator, triangular and rectangular, trapezoidal and so on are distinguished. Triangular is used exclusively for the installation of sanitary systems and its elements.

In addition, the thread is divided according to the type of direction of the turns into right and left.

Depending on the purpose of the thread, fastening and special threads are distinguished. Special ones are called rectangular ones, and triangular ones are called fastening ones. The triangular one is called fastening because it is cut only on the fastening elements of the structure: nuts, screws, bolts. The thread pitch is the distance between the tops and bottoms of adjacent turns.

The profile angle is the angle formed by the intersecting sides (edges) of the turns.

The distance from the beginning to the end of the thread is called its depth.

The outer diameter is the distance between points on two sides of the thread that lie opposite to each other. The inner diameter is the distance between the bases of opposite sides. The distance between the top and the bottom of the opposite side is called the average diameter.

According to the system of measures, the triangular type of thread is metric and inch. Metric threads have the shape of equilateral triangles at the apex with an angle of 60 degrees. This type is used in instrument making and mechanical engineering. The internal diameter of the section and the external size of the screw with metric types are calculated in millimeters, while the pitch can be calculated in millimeters and its fractions.

In profile, the inch version looks exactly the same as the metric one, but the apex angle is 55 degrees. It is calculated in inches and differs from the metric type in a different step.

The inch variety is used when assembling sanitary-type parts. It is divided into pipe and fastening.

These two types differ from each other in that the fastener has a larger pitch, which guarantees a reliable connection of the structure, and is used for cutting nuts, bolts, rods and holes. Pipe is used for pipe connections.

It is smaller than the fastening one because its depth is limited by the thickness of the pipe wall. The density of pipe threads is noticeably greater than fastening threads due to the numerous turns per inch of product length.

External thread cutting

External threads on rods, bolts and screws are manually cut with dies. Depending on the device, they are divided into round, prismatic, solid, and sliding.

Prismatic thread has a pair of identical halves, mounted in a frame-shaped clamp with handles. On a pair of outer sides of these dies there are prismatic grooves, which are intended for the prismatic protrusions of the die.

Sliding dies are located in the die so that the numbers on its sections are opposite the same numbers on the frame. Otherwise, the product will be damaged. They are attached with persistent screws. A steel plate-cracker is installed between the stop screw and the die so that the device does not burst when pressed by the screw.

The round die is secured in the easy-holding collar with two and four stop screws.
Using the sliding type, you can cut threads if there are imperceptible deviations in the diameter of the rod, which is unacceptable when cutting with solid round dies. With a smaller rod diameter, an incomplete thread is cut, and with a larger diameter, an even thread is cut.

Threading from the inside

The internal thread is cut independently using taps inserted into the driver.
The tap has a fence part (its end), which is necessary for cutting, a calibrating part (middle), used for guidance when cutting a hole and calibration, and a tail part, which has a square head in cross-section, to hold the tap in the collar when cutting.

When moving from insufficient to full metric or inch fasteners, use a set of taps that includes three taps of varying depths.

Basic thread locations

The connection of pipes for supplying gas or liquids is made in such a way that cylindrical pipe threads are cut or rolled at their ends. The pipe ends are attached to each other using connecting elements.

When connecting pipes for water or gas, short and long cylindrical threads are used. The last two turns are called runaway. It is formed due to the design of the die, in which the first turns are countersunk. Thanks to the run-out, it is possible to jam the coupling on the pipe, which guarantees a reliable tightness of the connection with the sealing material.

The length of the short type should be slightly less than half the length of the coupling. Then there should be a gap of 2-3 millimeters between the ends of the connected structures, which allows the coupling to jam at the run-out. For connections that cannot be disconnected using fittings, the short version is used. Such a connection can be disconnected on an installed pipeline only by cutting the pipe products.

In order to separate the assembled pipes without cutting them, a puller is used.
It includes a coupling, locknuts and a long thread, which must be of such a size that when connecting the drive, the locknuts and coupling can be easily screwed onto its surface. The sizes of short and long threads vary depending on the size of the pipes.

In order not to use excess metal, pipes with thin walls are often used in heating systems and gas supply systems, since their external cross-section diameter is almost the same as the internal one, unlike water pipes, a pipe is usually rolled onto the pipe, with the maximum permissible wall thickness There should be no fewer similar pipes than when cutting pipe threads on gas and water pipes.

DIY thread cutting equipment

On pipes for small volumes of work, external threads can be cut with your own hands using pipe clamps, using fixed or sliding dies.

Initially, the pipe is clamped into a clamp, the end of the pipe is cleaned of scale using a file, after which the cut part is lubricated with sulforesol or drying oil.

A special tool is installed on the pipe - a clamp, which has sliding dies, and by gently hitting the handle of the faceplate with a hammer or mallet, the guide dies are brought close to the pipe, then everything is secured with bolts. In addition, based on the risk of the faceplate, cutting dies are installed. Then they begin to rotate the tool clockwise, while simultaneously pressing on it.

In the pipe clamp body, on one side there are four holes for the dilution die, and on the other side there are three holes for the guide die. The cutting guide dies are moved apart, and the faceplates are brought together, which are attached to the body with clamping rings.

In the planes adjacent to the body, the faceplates have spiral grooves into which the die pins fit. If you turn the faceplate, the pins begin to slide along the spiral grooves, and the dies come closer together (if you turn the faceplate to the left) or gradually diverge (if you turn the faceplate to the right).

At a time when the dies are already mounted in the required position, the faceplate is secured using clamping bolts.

Pipe dies are manufactured with a pair of sets of cutting dies: for cutting threads on pipes measuring 20 or 15 millimeters and for cutting pipes with a diameter of 25, 38, 32 and 50 millimeters.

For pipe clamps, radial double-sided or radial single-sided dies are used. Dies are produced in 4 copies per package. Each has a designation with a size and a serial number from one to four.

The corresponding numbers are located at each slot on the body of the clamp. The pipe has replaceable bushings for different pipe diameters, located in the guide flange and secured with screws.

The latter is secured with screws to the body, where the corresponding die numbers are installed.

Pipe clamps have the advantage of the highest quality of threads obtained on products and structural strength. The disadvantage of this equipment is its large mass and the need for serious maintenance.

When cutting a 50 mm thread, it is necessary to rearrange the guide strips, turning them 180 degrees, then with the short side inside the die.

Mayevsky technology dies for threading pipes

Equipment such as the Mayevsky clamp is often used. This device has split dies consisting of two parts. A separate part of the rams corresponds to a certain pipe size. The dies, depending on the number indicated in the socket and on the die, are mounted in the housing socket using screws according to the marks marked on the dies of the required size and on the body. A thrust cover fastened with screws is placed on the dies.

Klupp Mayevsky - appearance

This equipment is produced in two sizes: for cutting threads with a diameter of 15 and 20 millimeters and for threads with a width of 25 and 32 millimeters.

Such a device has the following advantages: low weight, ease of design and maintenance, and the ability to quickly replace dies.

Clutches with ratchet for thread cutting

This equipment is used for cutting threads of 20, 25 and 15 millimeters. A head with various dies is fixed in its body. At the bottom of the head there is a ratchet wheel that rotates the die head and die.

A pair of ratchets are installed in the clamp body, closing the cheeks. Using the handle, the clamp head can be rotated. Cutting is done by rocking the handle with the ratchet turned on.

Once the cutting is complete, the ratchet is turned on, which engages the teeth of the ratchet wheel as the handle swings and drives the round die.

Using a ratchet die, you can cut threads in areas of the structure where it is impossible to use traditional tools. This happens especially often when carrying out repair work.

In order to cut a pipe thread, the product is clamped in a clamp so that the protruding end to be cut is short. This is due to the fact that the long end of the pipe may become deformed when cutting. The end of the threaded end should be located at an angle equal to 90 degrees to the axis of the threaded pipe.

The device is installed on the pipe with guide dies and guide rings according to such a system that the cutting dies extend onto the pipe by 1-2 turns. On pipes, the threads are lubricated with oil to keep the dies clean and cool.

Before starting cutting with a die, you need to check the installation rules of the cutting die, that is, the number of the socket in the body must match the number of the die.

To cut threads, the equipment rotates and moves forward. In one circle, cutting is carried out on pipes up to 25 millimeters, in two – on pipes with a width of more than 25 mm. The dies in the die are approached using a faceplate or screws.

Upon completion of work, the clamps should be disassembled and cleaned.

Source: https://glawtruba.ru/operacii-s-trubami/kak-pravilno-narezat-rezbu-na-trube.html

Rules for threading pipes - possible options

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To assemble modern pipelines, pipes made of plastic or metal can be used, and a welding machine is used to connect plastic pipes. As for metal products, their assembly involves the presence of threaded fittings: this ensures maximum connection strength. To implement this method, threads will need to be cut on the pipes themselves.

What tool do you need?

Threading pipes will require the following equipment:

1. Tape measure, pencil, caliper . To assemble the pipeline, it is necessary to develop a diagram in advance. First, a pipe with the specified length is taken: markings are made with a tape measure and a pencil. Using a caliper, the diameter is measured and suitable devices are selected. When marking, it is important to maintain considerable precision and accuracy, since any deviation from the specified size leads to a violation of the correctness of the entire structure. As a result, in such cases it is often necessary to redo the entire pipeline.
2. Bulgarian . Using this tool, pipes are cut according to the marked marks. A simple hacksaw for metal can perform the same functions.
3. Vise . During operation, the pipe must be securely fixed in a strictly horizontal position.
4. Machine oil or other lubricant . To facilitate manual thread cutting, it is practiced to lubricate the tool and the area being processed with a special substance.
5. Thread cutting tools . Pipe threads can be cut with a die, a die or a tap. Which tool to use depends on the type of thread being cut and the preferences of the performer. For different jobs, different pipe threading kits are used, depending on the situation. The external thread is cut with a die, which is held by a die or die holder. To apply internal threads you will need taps.

Do-it-yourself thread cutting

How to cut pipe threads yourself?

Self-threading begins with a number of preparatory measures:

1. Cutting a piece of pipe to size . When replacing a damaged section of a pipeline, the first step is to carefully cut out this section in a direction strictly perpendicular to the wall. If this condition is not met.
2. Cleaning the thread area . From the place where the pipe thread will be cut, all paint and corrosion must be completely removed: if this is not done, the work can be clearly difficult.
3. Chamfering . To make the work easier, you need to remove the chamfer from the ends of the pipe.

Thread cutting using a die

The die is used for cutting external threads, which requires the following operations:

• Select a die with the required diameter. To make the selection correctly, you must definitely check it with a caliper.
• Lubricating the internal cavity of the clamp and the prepared area on the pipe using machine oil.

Source: https://trubaspec.com/montazh-i-remont/pravila-narezaniya-rezby-na-trubakh-vozmozhnye-varianty.html

How to cut threads on a plastic pipe?

Articles

In order to securely connect a tap to a pipe, or install a heating device in a heating system, it is important to know how and with what to cut a thread on a pipe.

After all, most shut-off valves have threads; accordingly, connecting such elements by welding is impossible.

Thread on a water pipe

For example, if you have to install a new washbasin or toilet in your apartment, and it is not possible to unscrew a long-term connection on a steel water supply system, then the best option is:

1. Turn off the water supply;
2. Using a grinder, cut off part of the pipe near the installation site of the washbasin;
3. Cut pipe threads;
4. Install a ball valve or tee on the pipe;
5. Connect it with a flexible hose to the washbasin tap.

This work can easily be carried out by a qualified plumber. However, any apartment owner, having purchased a tool for cutting threads on pipes, is able to carry out this work independently.

Threading dies

Today, to equip a pipe with a threaded connection, 2 types of thread-cutting devices are used:

1. Threading dies;
2. Pipe clamp.

With their help, you can cut threads on any sewer or water pipe that is used in the utility networks of residential buildings and private cottages.

Pipe clamp

Advice!

If you have never cut a thread, it will be difficult to do it with a die. The slightest misalignment of the tool can lead to a defect.

Therefore, it is better to use a clamp, since it has a guide that greatly simplifies the cutting process.

Let's brush up on the theory behind the threading process.

So:

• threading on pipes is the formation of a screw surface on the outside of a pipe (plumbing or heating system);
• the screw surface is a connecting element rotating uniformly around the axis of the fitting,
• tee or tap, with uniform translational movement along this axis;
• thread pitch is the translational movement of the screwed element relative to the thread axis, corresponding to one full revolution.

In other words, in order to install shut-off valves, it is necessary to cut a thread on the pipes, the pitch of which coincides with the pitch of the connecting elements. Then such a connection of sewer or water pipes will be sealed and durable, and able to withstand high pressure.

Thread cutting work

To carry out this operation yourself, you need to purchase a pipe threading set. These can be either dies of the required diameter, or a more practical set of dies.

Basic requirements before starting work:

• before threading, the pipe must be cleaned of rust and old paint;
• the lead-in chamfer must be removed on its end surface;
• use only high-quality cutting tools in your work;
• It is imperative to have lubricant for efficient operation of the cutting tool and removal of chips.

Caution: pipe threading dies require some skill. Therefore, before starting work, you should practice on a piece of an old pipe so as not to spoil the water supply or sewer system.

Professional pipe threading kit

Preparatory work for cleaning the pipe and chamfering is best done using sandpaper and a file:

• thoroughly clean the surface of the pipe to a metallic shine;
• Use a file to chamfer the end of the pipe.

Cleaning the pipe before threading

The next stage is direct threading, which differs in the sequence of actions, depending on the selected tools.

Using dies

If you purchased dies for cutting pipe threads and a die holder, then the procedure will be as follows:

1. we clamp the pipes in a vice, or fix them in a convenient way so that the pipe remains motionless during the cutting process;
2. install the die into the die holder and fix it with screws;
3. apply oil to the pipe and to the cutting edges of the die;
4. carefully place the tool on the pipe and, rotating clockwise, cut the first thread pitch;
5. We make sure that the tool is perpendicular to the pipe;
6. Having cut the thread to the required length, unscrew the die and run it again.

Thread cutting with a die

Application of the clamp

A simpler version of thread cutting can be achieved using a die. This is a modernized die, equipped with a special guide and ratchet. Most often sold as a pipe threading kit.

The cutting process will be as follows:

1. install a screw of the required diameter from the purchased set into the ratchet;
2. apply oil to the cutting edges;
3. We put the guide on the edge of the pipe;
4. we begin to twist the ratchet, cutting the thread;
5. lubricate the pipe and cutting edges during operation.

Cutting pipe threads using a clamp

Cutting threads on a pipe is not that difficult

Articles

In order to securely connect a tap to a pipe, or install a heating device in a heating system, it is important to know how and with what to cut a thread on a pipe.

After all, most shut-off valves have threads; accordingly, connecting such elements by welding is impossible.

Thread on a water pipe

For example, if you have to install a new washbasin or toilet in your apartment, and it is not possible to unscrew a long-term connection on a steel water supply system, then the best option is:

1. Turn off the water supply;
2. Using a grinder, cut off part of the pipe near the installation site of the washbasin;
3. Cut pipe threads;
4. Install a ball valve or tee on the pipe;
5. Connect it with a flexible hose to the washbasin tap.

This work can easily be carried out by a qualified plumber. However, any apartment owner, having purchased a tool for cutting threads on pipes, is able to carry out this work independently.

Threading dies

Today, to equip a pipe with a threaded connection, 2 types of thread-cutting devices are used:

1. Threading dies;
2. Pipe clamp.

With their help, you can cut threads on any sewer or water pipe that is used in the utility networks of residential buildings and private cottages.

Pipe clamp

Advice!

If you have never cut a thread, it will be difficult to do it with a die. The slightest misalignment of the tool can lead to a defect.

Therefore, it is better to use a clamp, since it has a guide that greatly simplifies the cutting process.

Let's brush up on the theory behind the threading process.

So:

• threading on pipes is the formation of a screw surface on the outside of a pipe (plumbing or heating system);
• the screw surface is a connecting element rotating uniformly around the axis of the fitting,
• tee or tap, with uniform translational movement along this axis;
• thread pitch is the translational movement of the screwed element relative to the thread axis, corresponding to one full revolution.

In other words, in order to install shut-off valves, it is necessary to cut a thread on the pipes, the pitch of which coincides with the pitch of the connecting elements. Then such a connection of sewer or water pipes will be sealed and durable, and able to withstand high pressure.