Tapping is the process of machining a hole or rod in a part that uses a specialized threading tool to produce an external or internal helical thread consisting of projections and alternating spiral grooves.
Cutting is done on bolts, nuts and pipes used in split piping systems and other structural details. If the pipeline is installed manually from pipes on which there is no thread, then it will be important for you to understand how you can cut a thread on a product with your own hands. The main characteristics of any thread are its depth, pitch, profile angle, profile, average, outer and inner diameters.
Required thread information
A thread profile is a cross-sectional figure near a turn. Depending on this indicator, triangular and rectangular, trapezoidal, and so on are distinguished. Triangular is used exclusively for the installation of a sanitary system and its elements.
In addition, the thread is separated from the type of direction of the turns into right-hand and left-hand.
Depending on the purpose of the thread, there are fastening and special threads. Special ones are called rectangular, and fastening triangular. Triangular got the name 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 threads.
The profile angle is the angle formed by the intersecting sides (faces) of the turns.
The distance from the start to the end of the thread is called its depth.
The outer diameter is the distance between the points of the two sides of the thread that lie opposite each other. The inner diameter is the distance between the bases of the opposite sides. The distance between the top and 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 instrumentation and mechanical engineering. The inner diameter of the section and the outer 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 version, but the apex angle is 55 degrees. It is calculated in inches and differs from the metric view in a different step.
The inch variety is used when assembling sanitary-type parts. It is divided into pipe and fixing. These two types differ from each other in that the fastener has an enlarged pitch, which guarantees a reliable connection of the structure, and is used to cut nuts, bolts, rods and holes. Tubular is used when connecting pipes. It is smaller than the fastener because its depth is limited by the thickness of the pipe wall. The density of the pipe thread is significantly higher than the fastening thread due to the numerous threads per inch of the product length.
It will take
- Klupp for the required pipe diameter.
- Adjustable wrench (gas).
Klupp is a threading tool, such as a die, only this is a nozzle with a guide skirt. It must be purchased from a plumbing store. There is no shortage of them, so you will find them without problems, even in the village.
In this case, the Chinese version is presented, which is quite good.
Related article: How to patch a hole in a drywall wall
There is such a thing in the region of 200-500 rubles. It all depends on the diameter and the margin. Running models for diameters 1/2, 3/4 inches and inch as in my version.
You can ask the plumbers for the Soviet counterpart, if there is such an opportunity. Then it will be generally free of charge for you.
Outside threading
Outside threads on rods, bolts and screws are manually cut with dies. They are divided depending on the device into round, prismatic, solid, sliding. The prismatic thread has a pair of identical halves that are fixed in a frame-shaped die with handles. On a pair of outer sides of these dies, prismatic grooves are located, which are intended for 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 stubborn screws. A steel plate-cracker is installed between the stop screw and the die so that the device does not burst when pressed with the screw.
The round die is fixed in the easy-holder 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 diameter of the rod, an incomplete thread is cut, and with a larger diameter, an even one.
Threading set for pipes and rules for its use
Ideal for home use, this is a pipe threading kit. Klupp is a modernized die that has a special guide and ratchet. The tools in the kit can be different, for example:
- Sliding
... As a rule, they consist of cutters, the distance between which can be adjusted. Allows you to cut threads in several passes, accurately and efficiently. - Monolithic
... The tool has a cylindrical shape with an internal hole and is installed in a ram holder. Allows you to make a thread in one pass.
Depending on the diameter of the pipe and the direction of the thread (right, left), a drill is selected. Further, the work process is as follows:
- klupp is installed in the ratchet;
- oil is applied to the cutting part;
- a guide is installed on the edge of the pipe;
- the ratchet spins, making a thread;
- in the process, the edges and the pipe are treated with oil.
An example of threading using a die is presented in the video:
Internal threading
The internal thread is independently cut using taps inserted into the driver. The tap has an intake part (its end), which is necessary for cutting, a gauging part (middle) used for guidance when cutting a hole and sizing, and a tail, having a square head in section, to hold the tap in the collar when cutting.
When changing from undersized to full metric or fastening inches, a tap set is used that includes three taps of different depths.
Instrument composition
Klupp is a special threading device equipped with several sets of cutting radial dies. They have different diameters to suit a particular sewer or water pipe.
In addition to the klupp, you will need:
- set of taps for cutting internal threads;
- gas wrench or vise to fix the pipe;
- machine oil or any other;
- grinding machine for processing metal with a cut disc.
Note! When working with a grinder, you must protect your eyes and hands with special glasses and gloves.
Basic thread locations
The connection of pipes for supplying gas or liquids is made in such a way that pipe threads of a cylindrical shape 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, a short and long cylindrical thread is used. The last two turns are called escape. It is formed due to the design of the die, in which the first turns are countersunk. Thanks to the escape, the coupling can be jammed on the pipe, which guarantees the reliability of the tightness of the connection with the sealing material.
The length of the short type should be slightly less than half the length of the sleeve. Then a gap of 2-3 millimeters should remain between the ends of the structures to be connected, which is allowed to jam the clutch on the run. For non-pluggable connections using fittings, the short version is used. Such a connection can be disconnected on an installed pipeline solely by cutting the pipe products.
In order to separate the assembled pipes without cutting them, a squeegee is used. It includes a sleeve, locknuts and a long thread, which must be sized so that when connecting the squeegee, the locknuts and sleeve can be easily screwed onto its surface. The dimensions of the 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 outer section diameter is almost the same as the inner one, unlike water pipes, a pipe is usually rolled onto the pipe, with the maximum allowable wall thickness such pipes should be no less than when cutting pipe threads on gas and water pipes.
Carving tools
First of all, you need to stock up on all the necessary tools. There is a special electrical unit on sale, but when buying it, you should take into account the dimensions of the tool. It is difficult for a unit with a large size to cut threads on a pipe near a wall.
The best option is to do the work manually. In order to cut a thread on a pipe near the wall, you will need the following tools:
- Die holder;
- Two dies;
- Sealing lubricants (grease, machine oil);
- File or grinder.
The thread on the pipe near the wall should be such that the nut can be removed without difficulty. In some cases, people cover the assembly joint with a dye compound. This is not recommended. Especially for these purposes, there are lubricants and fum tapes. What are seals for? They prevent leaks. With them, tightening and removing the nut will occur without problems.
Instructions
No special knowledge is required to thread a pipe near a wall. All work is carried out according to the standard scheme. In some cases, it is necessary to slightly hollow out the wall so that you can cut the threads without significant effort.
Shut off the riser before starting work. Then the structure is cut off, leaving the area for threading. Be careful when cutting the pipe. Make sure that the cut is smooth. This will make it quicker and easier to fix the plate. If the cut is not very smooth, you can use a grinding wheel to give it the necessary texture.
In order to cut a thread on a structure near the wall, you need to use a die. The chamfer on the cut will help to make the first turn easier. Before work, it is recommended to coat the die and the pipe near the wall with grease. Then the die is put on the structure. In order to cut the product, careful rotational movements are performed: 2 turns forward and 1.5 turns in the opposite direction. Try to do the job as carefully as possible.
For reliable fixation, it is required to perform 7 turns, which, in total, is 10 millimeters. Make sure that the plate advances correctly. Its movement should be smooth, slow and precise. Do not jerk.
Cutting a thread on a pipe with a large diameter, located near a wall, is a very difficult task, especially for a layman. In this case, the die can be replaced with a die. In shops you can find hand and power tools. The manual version is cheaper, but it is easier to work with an electric die. The choice is yours.
When performing work, it is important to carefully secure the structure. It is good if you are not alone in doing this. If there are two squeegees on the structure, it is recommended to purchase a tap or a special tool for making turns by hand to make turns.
Related article: How to fix insulation to a brick wall
It is recommended to coat the turns with grease before working with the crane. You can use lard as it. If no sealing grease is available, fum tape can be used. For the tap, a silicone gasket is required. So the job is done. However, this is not all. It is required to check the structure for reliability and quality, to conduct an inspection. After a visual inspection, it is recommended to open the water and see if the structure is leaking. If all is well, the job is done.
DIY threading equipment
On pipes with small volumes of work, do-it-yourself external threads can be cut using pipe plugs, using non-sliding or sliding dies.
Initially, the pipe is clamped into a clamp, the end of the pipe is cleaned from scale with a file, after which the cut part is lubricated with sulfofresol or drying oil.
A special tool is installed on the pipe - klupp, which has sliding dies, and with gentle blows on the faceplate handle with a hammer or mallet, guide dies are brought close to the pipe, then everything is fixed with bolts. In addition, based on the risk of the faceplate, cutting dies are installed. Then the tool begins to rotate clockwise, while simultaneously pressing on it.
In the body of the pipe die, on one side there are four holes for the cutting die, and on the other side there are three holes for the guide die. The cutting guide dies are bred, 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, in which the pins of the die enter. If you turn the faceplate, the pins begin to slide along the spiral grooves, and the dies come closer (if you turn the faceplate to the left) or gradually diverge (if you turn the faceplate to the right). At the time when the dies are already mounted in the required position, the faceplate is secured with clamping bolts.
Pipe die sets are made with a pair of sets of cutting dies: for threading pipes of 20 or 15 millimeters in size and for cutting pipes with a diameter of 25, 38, 32 and 50 millimeters.
For pipe dies, radial double-sided or radial one-sided dies are used. Dies are produced in 4 copies per package. Each has a designation with a size and serial number from one to four. Corresponding numbers are located at each slot on the body of the klupp body. The pipe has replaceable sleeves for different pipe diameters, located in the guide flange and fastened with screws. The latter is fastened with screws to the body, where the corresponding plate numbers are installed.
Pipe couplings have the advantage of the highest quality of the resulting thread on the products and structural strength. The disadvantage of this equipment is its large weight and the need for serious care.
When cutting a 50 mm thread, it is necessary to rearrange the guide strips by turning them 180 degrees, then with the short side inside the die.
Slicing development
The pipe threading sequence consists of the following steps:
- They clean the desired section of the pipe from rust, other irregularities and paint drips of the outer diameter of the pipe.
- The required section of the pipe is abundantly lubricated with machine oil or sulfofresol, due to which the load on the handle during cutting will be much less. The same can be done for dies / dies.
- Securely fix the pipe in a vice. Along with this, the end of the pipe protruding for cutting should not be more than 5–8 of its diameters, otherwise the cutting accuracy is not guaranteed. Dies with a guide sleeve or die plates do not require such restrictions.
- The pipe is prepared for cutting, for which purpose a lead-in cone with a height of at least half the height of the die is obtained with a file at the end. At this point, a running thread is formed, if this is critical, then it can then be removed with a hacksaw for metal.
- A die or klupp is planted, and, vigorously rotating the knob, they acquire the desired threaded section. be directed not to forget that the length of the cut section of the thread must be a couple of turns longer than the required one. To be sure, it is possible to drive the die over the cut area a couple of times.
So, if you begin to follow the recommendations and instructions suggested in the article, you can quickly and properly cut threads on the pipe. Do you have any questions about the topic? Then ask questions by writing a comment on the article.
Klupps of Mayevsky's technology for threading on pipes
Equipment such as Mayevsky's klupp is often used. This device has two-piece split dies. A separate part of the dies corresponds to a specific pipe size. The dies, depending on the number indicated in the socket and on the dies, are mounted in the housing socket using screws according to the risks marked on the dies of the required size and on the housing. A persistent cover fastened with screws is placed on the dies.
Klupp Mayevsky - appearance
This equipment is produced in two sizes: for threading 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 construction and maintenance, the ability to quickly replace the dies.
How to thread a pipe near a wall
Often times, threading needs to be done on site, with the piping partly anchored to the water or heating system. In hard-to-reach places, it is impossible to thread a thread on a pipeline installed near the wall with a die with a knob. For such purposes, you will need to use a threading device such as a ratchet die. With its help, the threading process is simplified several times.
The manual threading procedure is carried out as follows:
- A nozzle of the corresponding diameter is fixed in the clamp of the klupp, after which you can proceed to the procedure itself.
- The pipe surface is cleaned - the working area.
- The area to be cut must be cleaned until a metallic sheen appears.
- A chamfer is made at an angle of 45-60 degrees.
- The material is lubricated with Litol or Solidol.
- A wrench is put on the working area of the pipe.
- Moderate reciprocating rotations of the tool are performed.
As with a die, and when working with a die, you need to make a half turn back after each new thread to remove the metal edge. To facilitate the process of threading, you can use an electric die cutter, however, it is rational to purchase such a tool only if you need to use it daily.
On pipes, you can cut not only external, but also internal threads, for which taps are used. However, the need to obtain a thread on the inner part of the pipeline arises only in rare cases. Knowing the peculiarities of self-threading, there will never be problems with the installation of water supply and heating systems.
