Elbow Manufacturing Process
a. Mandrel Method/Hot Forming Method
One of the most common manufacturing methods for manufacturing Elbows from pipes.
After heating the raw material, it is pushed over a die called “mandrel” which allows the pipe to expand and bend simultaneously. Applicable to a wide size range.
Characteristics of mandrel bending strongly depend on the integrated shape and dimensions of the mandrel.
Elbows manufactured by using hot mandrel bending have advantages of small thickness deviation and shorter bending radius than those of any other bending method type.
b. Extrusion Method/Cold Forming Method
In the cold extrusion method, a pipe with the same diameter as a finished product is pushed through a die and formed into its desired shape. Usually applied to stainless steel small to medium sizes elbows.
c. “UO” Method (Welding)
In this method the plate is cut out into a specially designed shape, it is formed first into a U-shape using a die and then into an O-shape or tubular form using another die, that is why this method is known as UO method. Once the fittings formed in tumbler shaped it is welded from inside and outside of the closing seam. A cut plate is 1st from in U shape and then in O shape
d. Hot Forming Die Bending Method
In this method the pipe is been inspected before any process. Then after cutting out pipe into specified length, it goes under elliptical forming using a die shown in the picture. For producing a specified radius for elbow, it bends in another die. In the next step the elbow goes under heat treatment. In the end shot blasting, cleaning, beveling and coating are done respectively to finalize the product.
Tee Manufacturing Process
a. Hydraulic Bulge Method (Cold Forming)
Cut piece of Pipe is placed in hydraulic die and liquid is fill inside the pipe, Hydraulic pressure pushes out the branch, in the fixed opening in the die.
This method gives the good surface finish. However, higher thickness Tee cannot be manufactured by this method.
b. “Monaka” Method
This manufacturing method is similar to Elbows, using steel plates as the raw material.
In this method two pieces of raw material plates cut out symmetrically and are press-formed and welded together.
c. Hot Extrusion Method
Tee with large diameters, heavy wall thickness and/or special material with challenging workability that cannot be manufactured using the hydraulic bulge method are manufactured using hot Extrusion Method.
In Hot Extrusion Method, normally bigger diameter pipe is used than the finished product size, the branch outlet is extruded from the pipe with help of extrusion tool.
Other dimensions of body and branch can also be adjusted by pressing the die if required.
Reducer Manufacturing Process
a. Outer Die Method
One of the most common method for manufacturing Reducers is using an outer die.
The pipe is cut and pressed in the outer die; compressing the one end of the pipe into a smaller size. This method is useful for manufacturing of small to medium size of reducers.
b. Plate Forming Method
Plates can also be used to manufacture Reducers.
In an UO method, plate is cut in a specially designed shape which is formed into a U-shape and an O-shape respectively, then finished with a single weld seam.
Cap Manufacturing Process
a. Deep Drawing Method
CAPs are manufactured by Deep Drawing method. In this method, Plate is cut out in a circle and formed by deep drawing die.
Stub End Manufacturing Process
a. Flaring Method
Stub Ends or Lap Joints Flange are manufactured by flaring method. Pipe end is a flare or spared out to form flange face. Stub ends are also manufactured by forging in which forge block are machined to final dimension.
Post time: Apr-07-2022