Technical Requirements
Technical parameters for tube mill line
①Type of tube mill: Φ406tube mill
②Tube O.D.: Φ114~Φ406mm
③Wall thickness: 4.0~12.7mm
④Type of pipe: round pipe
2. Selection of seam annealer
①Configuration: 600kW seam annealer 1 unit (3 sets)
②Model: KGPS-600kW/1kHz 2 set
KGPS-600kW/2kHz 1 set
③Temperature setting scope: 600~950℃
④Temperature control precision: ±1%
⑤Heating seam width: >20mm
⑥Cooling method: air-water cooling
3. Annealing speed for typical specification
①Calculation conditions: A. Type of pipe: round pipe B. Power:
1800KW; C. Annealing temperature rise: 950℃.
②Annealing speed:
Wall thickness (mm) | 3×600KW annealing speed (m/min) |
| |
| |
| |
| |
③Note:
- The speed in the above tables are calculated values on theory, and
the actual operating speed will be affected by many factors such as
mill modification, distance between inductor and pipe, seam
position and so on.
- The above annealing speed is calculated based on the temperature of
950℃. For different material of steel pipe and annealing
temperature, the annealing speed will be different.
Ⅱ. Technical Description for Seam Annealer
The application of seam annealing method promotes steel pipe
quality level. Induction heater is the main part of steel pipe
induction annealing equipment, which heat the pipe seam welded and
quenched to critical temperature, this process can reduce welding
stress and potential crack, and the produced close grains structure
can guarantee producing tenacious steel pipe meeting all standard
specifications. With the advantage of seam rapidly sectional
heating, the oxydation and deformation of steel pipe can be made to
be the minimum, and the precise diathermancy make the close grains
in seam area conformity with its parent material.
1. Main features for seam annealer
- The inverter adopts 1500A/2000V rapid SCR to form parallel inverter
circuit.
- The seam annealer power supply adopts the integration design of
rectifying/inverter to achieve more compact structure and
convenient maintenance.
- Adopt typical voltage and current intersection angle method timing
phase-lock control to make the operation more reliable and high
efficient; the adoption of tank circuit overvoltage/overcurrent
protection circuit ensures the power supply protection be more
precise.
- Adopt clutters wave start-up method with small impact and high
successful rate.
- Tank circuit and plane inductor can be installed on adjustable
mechanical positioning table, which can adjust the relative
distance between inductor and pipe seam to be fit for the pipe
online annealing of variable specifications.
- Adopt PLC and thermometric instrument of high precision to realize
temperature closed loop to control the annealing temperature.