5G efficient PFC inductor

[0031] Example 1

[0032] An annealing process for a silicon steel core 1 includes the following steps:

[0033] (1) Put the silicon steel core 1 into the furnace liner and hoist it into the annealing furnace, heat it to 600°C, keep it for 1.5h, and ventilate the nitrogen in the furnace liner to remove oily smoke;

[0034] (2) Continue heating the silicon steel core 1 to 770°C, and then keep it for 2.5 hours;

[0035] (3) Transfer the furnace bladder to the holding pit for cooling. After the silicon steel core 1 is cooled to 310°C, vacuum the furnace bladder, then open the inlet valve of the furnace bladder to introduce air, and control the air flow rate to 5m 3 / h;

[0036] (4) When the furnace bladder returns to normal pressure, take out the silicon steel core 1 and cool it naturally in the air.

[0037] Wherein, in the step (1), the nitrogen gas pressure in the furnace bladder is 0.06 MPa.

[0038] Wherein, in the step (1), the nitrogen flow rate during the ventilation process is contro

[0044] Example 2

[0045] An annealing process for a silicon steel core 1 includes the following steps:

[0046] (1) Put the silicon steel core 1 into the furnace liner and hoist it into the annealing furnace, heat it to 600°C, keep it for 1.5h, and ventilate the nitrogen in the furnace liner to remove oily smoke;

[0047] (2) Continue heating the silicon steel core 1 to 770°C, and then keep it for 2.5 hours;

[0048] (3) Transfer the furnace bladder to the holding pit for cooling. After the silicon steel core 1 is cooled to 310°C, vacuum the furnace bladder, then open the inlet valve of the furnace bladder to introduce air, and control the air flow rate to 5m 3 / h;

[0049] (4) When the furnace bladder returns to normal pressure, take out the silicon steel core 1 and cool it naturally in the air.

[0050] Wherein, in the step (1), the nitrogen gas pressure in the furnace bladder is 0.06 MPa.

[0051] Wherein, in the step (1), the nitrogen flow rate during the ventilation process is contro

[0057] Example 3

[0058] An annealing process for a silicon steel core 1 includes the following steps:

[0059] (1) Put the silicon steel core 1 into the furnace bladder and hoist it into the annealing furnace, heat it to 500°C, keep it for 2 hours, and ventilate the nitrogen in the furnace bladder to remove oily smoke;

[0060] (2) Continue heating the silicon steel core 1 to 750°C, and then keep it for 3 hours;

[0061] (3) Transfer the furnace bladder to the holding pit for cooling. After the silicon steel core 1 is cooled to 300°C, vacuum the furnace bladder, then open the inlet valve of the furnace bladder to introduce air, and control the air flow rate to 4m 3 / h;

[0062] (4) When the furnace bladder returns to normal pressure, take out the silicon steel core 1 and cool it naturally in the air.

[0063] Wherein, in the step (1), the nitrogen gas pressure in the furnace bladder is 0.04 MPa.

[0064] Wherein, in the step (1), the nitrogen flow rate during the ventilation process is c