When using elbow machines, we need to consider the way the 90 degree elbow center formula is calculated. Such as when we do Φ 610 Induction Bending Machine, if early know center formula so that it will be very convenient.

Elbow is a common connection pipe fitting used in plumbing installation. It is used to connect the pipe corner and change the direction of the pipe.

Other names :90° bend, right Angle bend, love bend, stamping bend, pressing bend, mechanical bend, welding bend, etc.

Purpose: connect two pipes with the same or different nominal sizes to make the pipes turn at 90°, 45°, 180° and various degrees.

Bending radius less than or equal to 1.5 times of pipe diameter belongs to the elbow, greater than 1.5 times of pipe diameter belongs to the elbow.

Technical requirements for manufacturing elbow:

You want to control the radius of curvature. For example, if the radius length is 1.5D, the radius of curvature must be within the required tolerance. Because most of these pipe fittings are used for welding, in order to improve the welding quality, the end is built into groove, leaving a certain Angle, with a certain edge, this requirement is also relatively strict, how thick the edge, how much the Angle is and the deviation range are specified, the geometric size is much more than the pipe fittings. The surface quality and mechanical properties of the elbow are basically the same as those of the pipe. For welding convenience, the steel material of the pipe is the same as that of the pipe to be connected.

• 1. 1.5 elbow center height A= diameter *1.524, in fact, is the multiple of diameter D*, the result of the number behind the decimal point will be rounded to take the number, such as the diameter D of 219 is 200, the center height is 200*1.524=304.8, take 305; For another example, the diameter of 114 is 100, and the central height is 100*1.524=15.4, taking 152. (applicable to the algorithm of curvature radius of elbows DN100 and above is convenient and quick to calculate).

• 2. Poke height = center height + radius of elbow. For example, the poke height of elbow 1.5 times the diameter of 219 =305+219/2=305+109.5=414.5

• 3. Length of the outer arc =(height of the center + radius)*3.14*2/360* degree, that is, (height of the poke)*3.14*2/360* degree, from which we can calculate the length of the outer arc of the 90-degree elbow = height of the poke *3.14/2

• 4. Inner arc length =(center height - radius)*3.14*2/360* degree

• 5, elbow length = elbow central height *3.14/2* elbow outside diameter/pipe diameter +(pipe wall thickness *3)+ machining allowance, such as 180*8 pipe blanking, push 273 elbow, using the above formula can be calculated, the cutting length =381*1.57*273/180+24=931.22mm+ machining allowance.