In the life of any person there is often a need to bend pipes. For such an operation, there is a special tool - a pipe bender. When a standard tool is unavailable, the question arises how to make it yourself.
The pipe bender is the device intended for are flexible pipes both on production, and in house conditions.
Various brands and designs of tools are offered in stores and on the market. At the same time, the acquisition of an expensive device in order to sometimes bend a small number of pipes is not always advisable. In this case, the person is puzzled how to make the pipe bender himself, and it turns out that the problem is completely solvable.
Features are flexible
As you know, the pipe is a hollow construction of a round profile. The main parameters are external Ø and wall thickness. Because of hollowness, uncontrolled bending can lead to its deformation (flattening, crushing, etc.) at the bend site. Eliminate dangerous deformation is possible only by bending with rounding of a certain minimum radius.
The scheme are flexible pipes.
The main parameter of the bend that requires control is the minimum diameter of the bend, which depends on the external diameter of the pipe and the thickness of its walls. For the most common pipes, the minimum bending diameter is:
- Ø 20-35 mm with a wall thickness of 2 mm - 5 Ø pipes;
- with a wall thickness of more than 2 mm - 3 Ø;
- Ø 35-60 mm with a wall thickness of over 2 mm - 4 Ø pipes.
During the bending, they are set by two main parameters - Ø and bend angle, determined by the purpose of the bend. At the same time, Ø of the required bend should not be less than the minimum diameter.Back to table of contents
Basic requirements for pipe benders
Scheme of the device bender.
- The device should fix in a stationary state one of the ends of the pipe at the bend site in order to ensure bending by simply moving the second end of the pipe.
- The pipe bender must provide a bend for a given Ø. Consequently, the design must contain a fixed part with the rounding of the desired Ø.
- At the initial stage of the bend, a tight contact of the pipe with the rounded element should be ensured and its displacement away from this element should be excluded.
- The device should allow movement of the free end in the direction that provides the bend.
- Finally, a natural requirement is simplicity in the manufacture and operation, availability of the materials used.
The simplest design bender
When bending steel tubes of small diameter or from a material of soft metals (aluminum, copper) or when bending with a small bend angle, a pipe bender of the simplest design can be effectively used. The principle of operation of such a device is based on the bending around the pattern.
Scheme manual pipe bender.
To make such a construction is very simple. A template is fixed on the base in the form of a flat surface (preferably wooden, in order to facilitate the fastening of parts). The template is made of boards, sawn so as to form a semicircle of the diameter specified for the bend. The thickness of the board must exceed the external diameter of the flexible pipe.
One end is secured in a vice. At the beginning of the contact of the pipe with the template, a stop is fixed on the base, which ensures that the template is pressed to the beginning of rounding. The stop can be made of any available material, including wood.
The pipe is passed between the template and the stop. By smoothly moving the second end manually, a bend is made along the template diameter at a given angle. If the force is not enough to bend, you can use the lever: insert a metal rod into the pipe or use a pipe of larger diameter and put it on top of the pipe being bent.Back to table of contents
The bend of pipes of larger diameter or thick-walled pipes causes a complication of the design of the pipe bender. Pipe benders using the principle of running around a fixed roller found spreading. This design of the device is close to the factory.
Drawing homemade pipe bender.
The design of the device is a durable metal frame in which a fixed roller and a lever with a movable roller, as well as a clamp for fixing the pipe, are fixed. A steel fixed roller should have Ø equal to the bending Ø. This condition largely determines the size of the entire device. The roller is made with a round hole with a diameter equal to the outer diameter of the bent pipe. A similar design has a movable version. Rollers are machined on a lathe.
The frame of the pipe bender must have high strength, since it is he who perceives the main load during bending. The material can be a steel pipe of rectangular cross-section or a strip of sufficient thickness.
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Pipe bender manufacturing
The framework of the pipe bender consists of two vertical strips (pillars) that are welded to the base in the final operation. On these side racks, holes are drilled according to the diameter of the axis under the fixed roller. The height from the base to the center of the hole must be 15–20 mm greater than the radius of the fixed roller. In this case, for universality, it is better to provide for turnover, that is, to bear in mind that a roller may have Ø equal to the maximum diameter of the bend. Side racks of the frame can be shortened so that they rise above the drilled hole at a height of 50-60 mm.
The scheme of the pipe bender with a chain.
The lever is made of two metal strips not less than 4 mm thick. The width of the strip is chosen 20 mm greater than the diameter of the hole for the roller axis. In the upper part of the lever must form a handle, so the strips after assembling the structure are interconnected (usually welded). In the lower part of the lever, a hole is drilled in the strips to install it on the axis of the fixed roller. Ø of this hole is equal to the diameter of the hole in the frame. The length of the lever below the hole is 10 mm. In the middle of the lever are drilled holes in the strips for the axis of the rolling roller. The distance between the centers of the holes under the axis is equal to the diameter of the fixed roller, provided that the diameters are equal.Back to table of contents
The movable roller is mounted on the axle and fixed by welding or cotter pin. Then the axis with a roller is installed in the holes of the lever and is also fixed with a cotter pin. The degree of fixation of this axis in the holes does not matter much.
Fixed mounted on its axis and rigidly fixed by welding. To him the requirement of mandatory immobility is put forward during operation.
On the axis of the fixed roller are installed side bands of the lever on both sides of the fixed roller. The lever on the axis should be free, i.e. the free rotation of the lever around the axis must be ensured. The axis of the fixed roller with a lever is fixed in the holes of the side pillars of the frame and fixed by welding. After that, you can complete the formation of the lever knob and secure the lever strips to each other.
The scheme with the size of a homemade pipe bender.
The base of the frame is made of weighted metal plate. A hole is drilled in the center and a thread is cut for the fixed roller retainer. Instead of drilling, it is possible to weld a nut into which the bolt lock is screwed into the base. Side racks of the frame with all fixed elements are welded to the base. A bolt is screwed into the hole for additional fixation of the fixed roller.
On the basis of the line pulling the pipe through the rollers is fixed latch. The design of the lock can be any, provided that the fixed end is secured. These can be axle shafts with bolt fastening and a diameter corresponding to the outer diameter of the tube. Use of collars is possible. The main requirement is to secure the clamp to the base when mounting the device and securely fix the end of the pipe when it is bent.
To reduce the size of the device, it is recommended to carry a lever handle about 25 cm long. A handle extension should be provided in the form of a pipe of the desired internal diameter.
In the absence of a welding machine, some welding connections can be replaced with bolted ones.
In particular, the mounting of the axles of both rollers can be accomplished with the help of bolts.
In order to make the pipe bender itself, you need to provide for the availability of such a tool as:
- electric drill with a set of drills;
- grinders with cutting and abrasive discs;
- hammer (sledge hammer);
The pipe bender - the device, simple on a design. It is quite possible to make it yourself in the presence of certain plumbing skills.