Manufacturing Procedure Specification of Seamless Steel Pipe

2 .Casting Continuous

3. Billet inspection and cutting Inspection item: heat no, length, marking, dimensions, surface quality, Certificate,
4. Rotary Hearth Furnace Maximum temperature: 1250±10˚ ˚C, computer aid control system
5. Piercing, rolling The surface quality of the mandrel bars is verified every beginning of shift.
6. Slight-Stretch reducing Sample inspection item: OD, WT, frequency : 1/15 to 20 min
7. Cutting Length
   Finished pipe OD : pipe body 60.3mm &88.9mm
   Cutting to range length according to customer’s requirement
8. Hot rolling
   Pipe body：
   Control of the pipe temperature at the exit of the stretch reducing mill. The pipe
   temperature at the exit of the stretch reducing mill shall be above the
   transformation point Ar3. Value is given by technology department. Temperature of
   re-heating furnace is
   recorded electronically. Temperature of the pipe is recorded manually every half
   hour.
   9.
   Straightening
   Check straightness ruler or rope, Roll pressure.
9. Sampling
   2 samples are taken for each lot of 200 pipes. (Each lot has 100 pipes minimum) 3
   specimens are cut from each sample pipe.
   Traceability marking (heat, lot and specimen number) is applied on the sample and
   then on the specimen by marker.

Tee extrusion method (Hot Forming)

The hot-extrusion process consists of enclosing a piece of metal, heated to forging temperature, in a chamber called a “container” having a die at one end with an opening of the shape of the desired finished section, and applying pressure to the metal through the opposite end of the container. The metal is forced through the opening, the shape of which it assumes in cross-section, as the metal flows plastically under the great pressures used.

Tees using raw material with a bigger diameter than the finished product, the branch outlet is extruded from pipe while the main body is being pressed. The outlet’s wall thickness can also be adjusted as needed. Applied to Tees with large diameters, heavy wall thickness and/or special material with challenging workability that cannot be manufactured using the hydraulic bulge method.

Butt weld fitting production procedure video

.https://www.youtube.com/watch?v=amtIiQ2flc4

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