The bend pipes of crosslinked polyethylene (PE) is directly connected with the deformation stresses compressive material on one side and tensile bending radius - with the other. Subject to the rules of forming avoids dangerous surge, resulting in damage to the tubular. To do this correctly calculate the minimum radius of HDPE pipe bending, permissible when dealing with this type workpieces.
The concepts and norms
Polyethylene relates to a sufficiently strong and at the same time ductile structures, allowing it to be heated softened condition and impart a desired shape articles. When properly organized critical violations molding process the material structure is usually not observed.
These properties allow the use of preforms of polyethylene pipes during installation, since in this case it is possible to easily bend around obstacles or change the direction of the intended seal. Under the minimum bend radius of a typical polyethylene pipe understood limit value at which it maintains its resistance and does not break.
This parameter, expressed in metric units, depends on the following factors:
- Temperatures tubular walls.
- Technical parameters related to its geometric proportions.
By the latter is meant indicator SDR, which is a ratio of the outer diameter of the tubular blank to the stated thickness of its walls.
Important! Law is valid, according to which with increasing SDR walls and the heating temperature is allowed to make bending arc of smaller radius.
In the calculation for the safe operation of bending the indicator should follow precisely these initial data (SDR and the temperature of the material or the environment).
Methods of forming tubes IPA
To bend the standard HDPE pipe in the home environment - you should use proven techniques successfully applied by craftsmen. Among the known approaches to this process are the following methods:
- The use of soldering or dryer building.
- Filling the cavity of the tube with hot water (boiling water).
- Filling it warmed up to 80-90 degrees particulate composition (salt or river sand).
Cranking plastic pipe at home are allowed by other methods (gas burner, for example).
Note! Possible and simplest approach consists in heating the blank pipe in the sun in the summer.
But this method straightening implement pipeline only in very hot weather (at temperature not lower than 30 degrees).
With a large volume of the tube blanks and the need to bend their special molding equipment require high precision. It is claimed in the industrial production and at home rarely used.
Tools and materials needed
In order to bend the plastic pipe on the basis of a low density polyethylene in various situations may require the following tools:
- a special molding machine;
- assembling or soldering powerful hair dryer (with the possibility of changing the operating temperature);
- conventional gas burner;
- bending pattern made taking into account the desired molding angle.
Each of these tools is suitable for the particular mode of bending pieces and can be used at home. When laying the water pipeline on a garden site recommends use of elements to ensure reliable reception of flanged joints.
They are listed below:
- Adapters for PE products.
- Tees and corners sedelochnye.
- Fitting, especially for compounds produced HDPE pipes.
In addition, for the joining of sections of different materials (stainless steel and PE, for example) need to be reserved couplings DRC.
And for the design of reliable branches within equip the site most convenient to use sedelochnymi taps Fischer, always available on the open market.
Calculation of minimum diameter for a given length
For rough calculations required bend radius two rigid lines 30 and 50 centimeter in length (their choice depends on the magnitude of the bend). The procedure is as follows:
- First measured bend radius already preformed pipes to be copied to the original preform.
- When measuring a strong bend taken at 30 cm line and applied to the ends of the curved tube, whereupon the distance is measured between it and the center of the workpiece.
- At low bending (greater length of the tube) the same operation is done with a line of 50 cm as shown in the picture below.
A - the interval (clearance), mm.
D - the diameter of the arc mm.
R - radius, which is supposed to bend the pipe in mm.
To understand what the desired parameter R should focus on the image below the text where a sample has a curved workpiece.
Based on the data obtained during the measurements more necessary to pick up the appropriate index value of radius (diameter) of the arc, the values of which can be found in specially prepared tables. They are located in the sources on the internet (which takes into account various options for pre-measurement).
Bending angle of 90 degrees
Often during the pipe installation requires perfect right angle, for which it's best to use a bending template. It is a basis in the form of a suitable size fiberboard with right angles. Main admissibility condition on the bending template - warming smooth bending zone, eliminating the possibility of disruption of the structure material.
Additional Information! If necessary, issue the pipe bend 90 degrees recommend warm portion whose length is equal to its six diameters.
Under this condition bend it is smooth and even.
recommendations made
During the molding work performed by one of the methods described workpieces bending, it is recommended to adhere to the following rules:
- When heated, a long fold should proceed slowly by performing this procedure stepwise (continuously moving from one portion to another molded).
- It is forbidden to bring the building dryer very close to HDPE product (otherwise it can just melt).
- Bend pipes of large diameter (110 mm) is allowed only on a special molding equipment.
- With self sedelochnyh manufacture of taps required heating temperature control element.
Important! When exceeding the permissible value of 120 degrees resulting angle may be different from the desired values in one direction or another.
To work independently with a polyethylene-based products are allowed to start only after thorough preparation for these procedures. Before forming products are encouraged to review the materials presented in the article.
