diff --git a/src/src/main/java/com/my/graphiteDigesterBg/move/MoveLiquidAdd.java b/src/src/main/java/com/my/graphiteDigesterBg/move/MoveLiquidAdd.java
index 8d6d01a..d1d244f 100644
--- a/src/src/main/java/com/my/graphiteDigesterBg/move/MoveLiquidAdd.java
+++ b/src/src/main/java/com/my/graphiteDigesterBg/move/MoveLiquidAdd.java
@@ -110,7 +110,7 @@ public class MoveLiquidAdd extends DiTaskMoveBase {
             slotIndex = slotGroupIndexList.get(pumpIndex*2+1);
         }
 
-        var tubeStatus = this.slot.getTubeStatus(slotIndex);
-        return ResHeatingTubeRackSlot.TUBE_STATUS_USED.equals(tubeStatus);
+        var tube = this.slot.getTubes().get(slotIndex);
+        return tube.getHasTube();
     }
 }
diff --git a/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackSlot.java b/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackSlot.java
index 56635af..7655040 100644
--- a/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackSlot.java
+++ b/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackSlot.java
@@ -41,17 +41,20 @@ public class ResHeatingTubeRackSlot {
     public String taskUuid;
     // manager
     private final ResHeatingTubeRackSlotManager manager;
-    // tube status list
-    private final List<String> tubeStatusList;
+    // tube rack location
+    private final List<ResHeatingTubeRackTubeSlot> tubes;
 
     // constructor
     public ResHeatingTubeRackSlot( ResHeatingTubeRackSlotManager manager, Integer index ) {
         this.isLocked = false;
         this.index = index;
         this.manager = manager;
-        this.tubeStatusList = new ArrayList<>();
+
+        this.tubes = new ArrayList<>();
         for ( int i = 0; i < 16; i++ ) {
-            this.tubeStatusList.add(TUBE_STATUS_EMPTY);
+            var tube = new ResHeatingTubeRackTubeSlot();
+            tube.setHasTube(false);
+            this.tubes.add(tube);
         }
     }
 
@@ -74,9 +77,11 @@ public class ResHeatingTubeRackSlot {
     // setup as error slot
     public void setupAsErrorSlot() {
         this.isErrorSlot = true;
-        this.tubeStatusList.clear();
+        this.tubes.clear();
         for ( int i = 0; i < 16; i++ ) {
-            this.tubeStatusList.add(TUBE_STATUS_EMPTY);
+            var tube = new ResHeatingTubeRackTubeSlot();
+            tube.setHasTube(false);
+            this.tubes.add(tube);
         }
     }
 
@@ -84,7 +89,7 @@ public class ResHeatingTubeRackSlot {
     public List<Integer> allocEmptyTubeIndexes( Integer count ) {
         List<Integer> indexes = new ArrayList<>();
         for ( int i = 0; i < 16; i++ ) {
-            if ( TUBE_STATUS_EMPTY.equals(this.tubeStatusList.get(i)) && indexes.size() < count ) {
+            if ( !this.tubes.get(i).getHasTube() && indexes.size() < count ) {
                 indexes.add(i);
             }
         }
@@ -92,23 +97,18 @@ public class ResHeatingTubeRackSlot {
             throw new RuntimeException("异常处理区试管空位不足");
         }
         for ( var index : indexes ) {
-            this.tubeStatusList.set(index, TUBE_STATUS_USED);
+            this.tubes.get(index).setHasTube(true);
         }
         return indexes;
     }
 
-    // set tube status
-    public void setTubeStatus( Integer index, String status ) {
-        this.tubeStatusList.set(index, status);
-    }
-
-    // get tube status
-    public String getTubeStatus( Integer index ) {
-        return this.tubeStatusList.get(index);
-    }
-
     // set rack position
     public void setRackPosition(String rackPosition) {
         this.rackPosition = rackPosition;
     }
+
+    // get tubes
+    public List<ResHeatingTubeRackTubeSlot> getTubes() {
+        return tubes;
+    }
 }
diff --git a/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackTubeSlot.java b/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackTubeSlot.java
new file mode 100644
index 0000000..71cdb81
--- /dev/null
+++ b/src/src/main/java/com/my/graphiteDigesterBg/resource/ResHeatingTubeRackTubeSlot.java
@@ -0,0 +1,23 @@
+package com.my.graphiteDigesterBg.resource;
+public class ResHeatingTubeRackTubeSlot {
+    // index of slot
+    public Integer index;
+    // has tube
+    private Boolean hasTube;
+    // rack code
+    public String rackCode;
+    // tube code
+    public String tubeCode;
+    // tube status
+    public String digestStatus;
+
+    // set has tube
+    public void setHasTube(Boolean hasTube) {
+        this.hasTube = hasTube;
+    }
+
+    // get has tube
+    public Boolean getHasTube() {
+        return this.hasTube;
+    }
+}
diff --git a/src/src/main/java/com/my/graphiteDigesterBg/task/TaskSampleAdd.java b/src/src/main/java/com/my/graphiteDigesterBg/task/TaskSampleAdd.java
index 2559896..c3a439f 100644
--- a/src/src/main/java/com/my/graphiteDigesterBg/task/TaskSampleAdd.java
+++ b/src/src/main/java/com/my/graphiteDigesterBg/task/TaskSampleAdd.java
@@ -60,7 +60,7 @@ public class TaskSampleAdd extends DiTaskBase {
 
         // 初始化试管架状态
         for ( int i=0; i<16; i++ ) {
-            slot.setTubeStatus(i, ResHeatingTubeRackSlot.TUBE_STATUS_USED);
+            slot.getTubes().get(i).setHasTube(true);
         }
         // 移动加液盘到观察视角
         liquidPlateMotor.moveTo("LiquidPlateCameraShot");
@@ -70,7 +70,7 @@ public class TaskSampleAdd extends DiTaskBase {
         var tubeRackEmptyList = statusConfirmAction.getResult(List.class);
         for ( var item : tubeRackEmptyList ) {
             Integer index = (Integer)item;
-            slot.setTubeStatus(index, ResHeatingTubeRackSlot.TUBE_STATUS_EMPTY);
+            slot.getTubes().get(index).setHasTube(false);
         }
 
         this.setStatus(TaskStatus.FINISHED);