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skills requirement:

●The surface is flat, the dimensional error is no more than 2mm, and there is no distortion.

●The weld seam is clear, no blisters, and no leakage after 3MPa water pressure test.

●The water in the water flows smoothly, and does not deform under the pressure of 3 MPa.

●Water mist, sizing, oil mist erosion.

●Material SUS304.