国家/地区 中国（2）
IPC部 B（2）
IPC大类 B05（2） C09（2） F16（2）
IPC小类 B05D（2）
IPC B05D005/00（2）
发明人
公开年 2023（2）
申请年 2022（2） 
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