So the means cannot control leak the material, then possibly is the graphite pad or the copper collar wears (for example seal face not to be smooth seriously, gap big).

如此办法不能控制漏料，则可能是石墨垫或铜环磨损较严重(如密封端面不光滑，间隙大)。

youdao

The collar is pressed equally according to different material, the machine could be set at different pressure, shape's temperature and pressing time.

回压均匀，可任意调节压力大小、模具的温度和压烫时间，可适用于多种不同的面料；

youdao

Nubby, shiny material familiar to varsity athletes surprisingly made sense on a coat that was paired with a goatskin collar shawl, lace-inset blouse and stretch-wool seamed pants.

WSJ: Weather's silver lining: coat comfort on runways