diff --git a/resources/views/rd/fire-shutter-drawing/index.blade.php b/resources/views/rd/fire-shutter-drawing/index.blade.php
index d490ead0..b8baeacc 100644
--- a/resources/views/rd/fire-shutter-drawing/index.blade.php
+++ b/resources/views/rd/fire-shutter-drawing/index.blade.php
@@ -1351,24 +1351,24 @@ function renderSbSide() {
             <text x="${ox+sD+vt+4}" y="${oy+srTopH+srDoorH/2-4}" fill="${doorStroke}" font-size="9" font-weight="700" text-anchor="start" font-family="Pretendard">후면</text>
             <text x="${ox+sD+vt+4}" y="${oy+srTopH+srDoorH/2+8}" fill="${doorStroke}" font-size="8" text-anchor="start" font-family="Pretendard" opacity="0.7">점검구</text>
 
-            <!-- ⑧ 밑면 점검구 (${bDoorW}mm) -->
-            <rect x="${ox+sbFrontW}" y="${oy+sH-vt}" width="${sbDoorW}" height="${vt}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1.5" stroke-dasharray="6 3"/>
-            <!-- 밑면 점검구 13mm 스크류 탭 -->
-            <rect x="${ox+sbFrontW}" y="${oy+sH-vt-f13}" width="${vt*0.5}" height="${f13}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="0.8" stroke-dasharray="3 2" rx="1"/>
-            <rect x="${ox+sbFrontW+sbDoorW-vt*0.5}" y="${oy+sH-vt-f13}" width="${vt*0.5}" height="${f13}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="0.8" stroke-dasharray="3 2" rx="1"/>
-            <!-- 밑면 접합부 직결피스 (나사 단면 표시) -->
+            <!-- ⑧ 밑면 점검구 절곡판 (5세그먼트: 17,13,main,13,17) -->
             ${(() => {
-                const y = oy+sH-vt/2;
-                const lx = ox+sbFrontW+vt*0.25, rx = ox+sbFrontW+sbDoorW-vt*0.25;
-                const r = Math.max(2.5, vt*0.25);
-                const screwCol = '#dc2626';
+                // 트레이 형태: 17mm 플랜지─13mm 스텝─본체─13mm 스텝─17mm 플랜지
+                const dx = ox + sbFrontW; // 점검구 좌측 가장자리
+                const dy = oy + sH;       // 밑면 레벨
+                const dw = sbDoorW;       // 점검구 폭
+                const df17 = f17, df13 = f13; // 플랜지 17mm, 스텝 13mm
                 return `
-                    <circle cx="${lx}" cy="${y}" r="${r}" fill="${screwCol}" stroke="#991b1b" stroke-width="0.8"/>
-                    <line x1="${lx-r*0.6}" y1="${y-r*0.6}" x2="${lx+r*0.6}" y2="${y+r*0.6}" stroke="white" stroke-width="0.8"/>
-                    <line x1="${lx+r*0.6}" y1="${y-r*0.6}" x2="${lx-r*0.6}" y2="${y+r*0.6}" stroke="white" stroke-width="0.8"/>
-                    <circle cx="${rx}" cy="${y}" r="${r}" fill="${screwCol}" stroke="#991b1b" stroke-width="0.8"/>
-                    <line x1="${rx-r*0.6}" y1="${y-r*0.6}" x2="${rx+r*0.6}" y2="${y+r*0.6}" stroke="white" stroke-width="0.8"/>
-                    <line x1="${rx+r*0.6}" y1="${y-r*0.6}" x2="${rx-r*0.6}" y2="${y+r*0.6}" stroke="white" stroke-width="0.8"/>
+                    <!-- 본체 (main span, 밑면 레벨) -->
+                    <rect x="${dx}" y="${dy-vt}" width="${dw}" height="${vt}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1.5" stroke-dasharray="6 3"/>
+                    <!-- 좌측 스텝 (13mm ↑, 본체 좌측 끝에서 상향) -->
+                    <rect x="${dx}" y="${dy-vt-df13}" width="${vt*0.7}" height="${df13}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1" stroke-dasharray="4 2"/>
+                    <!-- 좌측 플랜지 (17mm ←, 스텝 상단에서 좌측으로) -->
+                    <rect x="${dx-df17}" y="${dy-vt-df13}" width="${df17+vt*0.3}" height="${vt*0.7}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1" stroke-dasharray="4 2"/>
+                    <!-- 우측 스텝 (13mm ↑, 본체 우측 끝에서 상향) -->
+                    <rect x="${dx+dw-vt*0.7}" y="${dy-vt-df13}" width="${vt*0.7}" height="${df13}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1" stroke-dasharray="4 2"/>
+                    <!-- 우측 플랜지 (17mm →, 스텝 상단에서 우측으로) -->
+                    <rect x="${dx+dw-vt*0.3}" y="${dy-vt-df13}" width="${df17+vt*0.3}" height="${vt*0.7}" fill="${doorFill}" stroke="${doorStroke}" stroke-width="1" stroke-dasharray="4 2"/>
                 `;
             })()}
             <!-- 밑면 점검구 라벨 -->