国家/地区 中国（3）
IPC部 B（3）
IPC大类 C09（3）
IPC小类 C09D（3）
IPC C09D163/00（3）
发明人
公开年 2023（2）
申请年 2022（3）
专利权人

Preparing coating for screw thread, comprises e.g. providing workpieces with screw thread, pretreating screw thread part of workpieces with screw thread; sandblasting workpiece with screw thread after pretreatment; and preheating workpiece with screw thread after sandblasting.

SUN J, WANG Y, WANG L, LI R, SONG X, LIU X

Preparing internal spiral polyvinyl chloride drainage pipe, comprises e.g. bending and spiraling steel wire, extruding, injecting into brushing mechanism, carrying out spiral groove processing, forming inner spiral groove, spraying, extruding, painting and performing preliminary drying.

LIU Z

Preparing pipe material comprises cleaning mineral-inorganic composite materials, grinding, melting, casting and forming in combination with pipe mold by means of centrifugal casting, demolding and cooling, heating and densifying, and coating anti-corrosion coating.

WANG P