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Patent for Invention：Preparation method of porous surface heat exchange tube of thermally-sprayed iron-based powder

Patent for Invention：Preparation method of porous material of spraying wire mesh

Patent for Invention：Ultrasonic flaw detection method for computer-assisted checking

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Utility Model Patent Certificate：U-shaped tube bundle heat exchanger

Utility Model Patent Certificate：Special pipe penetrating tool for U-shaped pipe

Utility Model Patent Certificate：Pressing tool for eccentric reinforcement pad

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Utility Model Patent Certificate：Hoisting device capable of largely hoisting manhole cover

Utility Model Patent Certificate：Hoisting device

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