សម្ពាធផ្សារ ប្រេកង់ welded pipe welded pressure welded pipe is one of the main parameter of process welding, after the two edges of the tube is heated towelding temperature and squeezing produce welded under pressure to form a common metal grains that is mutly crystals.ចាប់តាំងពីទទឹងបំពង់មួយ ...
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