A conical rami wanda aka yanke wa damar lebur shugaban dunƙule da za a yi amfani da an kira wani countersink rami. Yana kuma iya a kira a matsayin conical rami da aka yanka a cikin wani PCB laminate, ko wani rami halitta ta amfani da wani rawar soja. Babban manufar ne to bari shugaban wata countersunk dunƙule, da zarar an saka da ci da gumi saukar a cikin rami, ya zauna tare da ja ruwa surface na laminate. A mazugi dimbin yawa rami, wanda aka yanke a cikin PCB laminate, shi ne wani countersink. An kullum amfani da su bayar da izinin Tapered shugaban a dunƙule zauna ja ruwa tare da saman ko kasan laminate.

An yafi amfani, don haka da cewa lebur shugaban dunƙule iya zama ja ruwa tare da surface to da tsabta look da kafuwa. Don tabbatar da daidai zane ga masana'antu, mafi masana'antun bukatar cikakkun bayanai na rami diamita. Suna kuma bukatar su san idan rami ne plated ko ba. Sanin idan rami ne farantin ko ba ne m saboda a wasu yanayi wani Unplated rami iya grounded da tsarin, wanda zai iya haifar da matsala da zai bukaci plating to gyara. Countersinks yawanci suna da wani 82 digiri ko 90 digiri kwana. Duk da haka, wasu kusassari ne zai yiwu cewa abokin ciniki zai bukatar samar da PCB qage.

Ga cikakken hakowa daga countersink ramukan, da wadannan bayanai da ake bukata:

▪ Wanne gefe na hukumar ne countersink rami ya kamata a fadi na sukar, a saman ko kasan?

▪ Shin kwatami da shaft ya zama ta hanyar plated ko ba-plated?

▪ Taper kwana ko countersink kwana

▪ Countersink diamita

▪ A ƙãre diamita na shaft na rami

▪ Zurfin na countersink ne da za a fadi na sukar

Kasa shi ne wani hoto wanda ya samar da wani misali da wani countersink rami:

A: Countersink kwana, D: Countersink diamita, d: Hole diamita, H: Hole zurfin