diff --git a/scripts/verify-nozzle.js b/scripts/verify-nozzle.js
index 8d6b113..64e8633 100644
--- a/scripts/verify-nozzle.js
+++ b/scripts/verify-nozzle.js
@@ -65,6 +65,9 @@ try {
     [1440, 900],
     [1280, 720],
     [1920, 1080],
+    [2048, 990],
+    [2560, 1238],
+    [1366, 768],
     [390, 844],
   ]) {
     await page.setViewportSize({ width, height });
@@ -75,6 +78,7 @@ try {
         width: document.documentElement.scrollWidth,
         height: document.documentElement.scrollHeight,
         scene: rect(document.querySelector("#scene")),
+        parts: JSON.parse(document.querySelector("#scene").dataset.nozzleBounds),
         labels: [...document.querySelectorAll(".nozzle-label")].map(rect),
         panel: rect(document.querySelector('[data-panel="nozzle"]')),
         foot: rect(
@@ -83,6 +87,14 @@ try {
       };
     });
     assert.ok(layout.width <= width);
+    assert.equal(layout.parts.length, 12);
+    layout.parts.forEach((part, index) => {
+      assert.ok(part.top >= 20 && part.bottom <= layout.scene.height - 28,
+        `${width} 部件 ${index + 1} 上下未裁切：${JSON.stringify(part)}`);
+      const inset = (layout.scene.width < 550 ? 90 : 144) + 8;
+      assert.ok(part.left >= inset && part.right <= layout.scene.width - inset,
+        `${width} 部件 ${index + 1} 不被标签遮挡`);
+    });
     if (width >= 1100) {
       assert.ok(layout.height <= height);
       assert.ok(layout.foot.bottom <= layout.panel.bottom + 1);
@@ -111,6 +123,7 @@ try {
       height,
       scene: layout.scene,
       labels: layout.labels.length,
+      parts: layout.parts,
     });
   }
   await page.setViewportSize({ width: 1440, height: 900 });
diff --git a/src/views/Monitor/NozzleFraming.js b/src/views/Monitor/NozzleFraming.js
new file mode 100644
index 0000000..f0a5c3e
--- /dev/null
+++ b/src/views/Monitor/NozzleFraming.js
@@ -0,0 +1,41 @@
+import * as THREE from "three";
+
+export function boxCorners(box) {
+  return [box.min.x, box.max.x].flatMap((x) =>
+    [box.min.y, box.max.y].flatMap((y) =>
+      [box.min.z, box.max.z].map((z) => new THREE.Vector3(x, y, z)),
+    ),
+  );
+}
+
+// 将部件包围盒全部纳入透视视锥，并留出两侧标签与底部说明空间。
+export function fitNozzleCamera(camera, controls, boxes, width, height) {
+  const bounds = boxes.reduce((result, box) => result.union(box), new THREE.Box3());
+  const center = bounds.getCenter(new THREE.Vector3());
+  const backward = camera.position.clone().sub(controls.target).normalize();
+  const right = new THREE.Vector3().crossVectors(camera.up, backward).normalize();
+  const up = new THREE.Vector3().crossVectors(backward, right).normalize();
+  const labelWidth = width < 550 ? 90 : 144;
+  const horizontal = Math.max(0.15, 1 - (2 * (labelWidth + 22)) / width);
+  const vertical = Math.max(0.2, 1 - 80 / height);
+  const tangent = Math.tan(THREE.MathUtils.degToRad(camera.getEffectiveFOV() / 2));
+  let distance = controls.minDistance;
+  for (const box of boxes) {
+    for (const point of boxCorners(box)) {
+      const relative = point.sub(center);
+      const depth = relative.dot(backward);
+      distance = Math.max(distance,
+        depth + Math.abs(relative.dot(right)) / (tangent * camera.aspect * horizontal),
+        depth + Math.abs(relative.dot(up)) / (tangent * vertical));
+    }
+  }
+  distance *= 1.04;
+  controls.maxDistance = Math.max(1000, distance * 2);
+  controls.target.copy(center);
+  camera.position.copy(center).addScaledVector(backward, distance);
+  camera.far = Math.max(1600, distance * 4);
+  camera.updateProjectionMatrix();
+  camera.lookAt(center);
+  controls.update();
+  camera.updateMatrixWorld(true);
+}
diff --git a/src/views/Monitor/NozzleScene.js b/src/views/Monitor/NozzleScene.js
index 18ffcfd..6b8775d 100644
--- a/src/views/Monitor/NozzleScene.js
+++ b/src/views/Monitor/NozzleScene.js
@@ -1,5 +1,6 @@
 import * as THREE from "three";
 import "./Nozzle.css";
+import { boxCorners, fitNozzleCamera } from "./NozzleFraming.js";
 
 const modules = [
   {
@@ -116,6 +117,10 @@ export class NozzleScene {
       return group;
     });
     this.build();
+    this.partBounds = this.parts.map((part) => {
+      const box = new THREE.Box3().setFromObject(part);
+      return box.translate(part.position.clone().negate());
+    });
     this.overlay = document.createElement("div");
     this.overlay.className = "nozzle-annotations";
     this.overlay.hidden = true;
@@ -287,30 +292,33 @@ export class NozzleScene {
   }
 
   focus() {
+    const { camera, controls } = this.owner;
+    camera.position.copy(controls.target).add(new THREE.Vector3(0.32, 0.42, 1).multiplyScalar(340));
+    this.fit();
+  }
+
+  boxes() {
+    this.group.updateMatrixWorld(true);
+    return this.parts.map((part, index) => this.partBounds[index].clone().applyMatrix4(part.matrixWorld));
+  }
+
+  fit() {
     const { camera, controls, container } = this.owner;
-    const narrow = container.clientWidth < 550;
-    const available = Math.max(
-      0.3,
-      (container.clientWidth - (narrow ? 180 : 300)) / container.clientWidth,
-    );
-    const distance = Math.max(340, 170 / (camera.aspect * available * 0.63));
-    controls.target.set(0, 22, 0);
-    camera.position.copy(
-      new THREE.Vector3(0.32, 0.42, 1)
-        .normalize()
-        .multiplyScalar(distance)
-        .add(controls.target),
-    );
-    controls.update();
+    if (!container.clientWidth || !container.clientHeight) return;
+    fitNozzleCamera(camera, controls, this.boxes(), container.clientWidth, container.clientHeight);
   }
 
   update(disassembled) {
-    this.amount += ((disassembled ? 1 : 0) - this.amount) * 0.09;
+    const target = disassembled ? 1 : 0;
+    const changing = Math.abs(target - this.amount) > 0.0001;
+    this.amount = changing ? this.amount + (target - this.amount) * 0.09 : target;
     this.parts.forEach((part, i) => {
       part.position
         .fromArray(modules[i].base)
         .addScaledVector(new THREE.Vector3(...modules[i].offset), this.amount);
     });
+    if (changing || this.lastDisassembled !== disassembled) this.fit();
+    this.lastDisassembled = disassembled;
     this.owner.container.dataset.nozzleExplode = this.amount.toFixed(3);
     this.annotate();
   }
@@ -328,6 +336,16 @@ export class NozzleScene {
       labelWidth = narrow ? 90 : 144;
     const slots = [[], []];
     this.group.updateMatrixWorld(true);
+    camera.updateMatrixWorld(true);
+    this.owner.container.dataset.nozzleBounds = JSON.stringify(this.boxes().map((box) => {
+      const points = boxCorners(box).map((point) => point.project(camera));
+      return {
+        left: Math.min(...points.map((point) => (point.x + 1) * w / 2)),
+        right: Math.max(...points.map((point) => (point.x + 1) * w / 2)),
+        top: Math.min(...points.map((point) => (1 - point.y) * h / 2)),
+        bottom: Math.max(...points.map((point) => (1 - point.y) * h / 2)),
+      };
+    }));
     this.parts.forEach((part, i) => {
       const p = part.getWorldPosition(new THREE.Vector3()).project(camera);
       slots[i % 2].push({ i, x: ((p.x + 1) * w) / 2, y: ((1 - p.y) * h) / 2 });