diff --git a/YLErpDAL/Modules/SwapModule/SwapDealIndexFixer.cs b/YLErpDAL/Modules/SwapModule/SwapDealIndexFixer.cs
new file mode 100644
index 00000000..0ba1acc9
--- /dev/null
+++ b/YLErpDAL/Modules/SwapModule/SwapDealIndexFixer.cs
@@ -0,0 +1,25 @@
+using System;
+using YLErp.Derivatives.Interest;
+
+namespace YLErp.Modules.SwapModule;
+
+/// <summary>
+/// SwapDealService 专用取价器：通过实例方法委托给 TryGetFloatRate(virtual)，
+/// 而非 Fr007IndexFixer.Instance 那样直接调 EodPriceQueryService。
+///
+/// 为什么不用静态 Instance：SwapDealService.TryGetFloatRate 是 protected virtual，
+/// 测试通过 override 它注入 stub 利率。静态 Instance 绕过这个接缝会让 45 个测试失败。
+/// 本类把 TryGetFloatRate 包成 IIndexFixer，既保留 virtual 接缝，又用上 IndexFixerBase。
+/// </summary>
+internal sealed class SwapDealIndexFixer : IndexFixerBase, IIndexFixer
+{
+    private readonly SwapDealService _owner;
+    internal SwapDealIndexFixer(SwapDealService owner) => _owner = owner;
+
+    public bool TryGetFixing(DateTime fixingDate, string underlyingCode, out decimal rate)
+    {
+        bool ok = _owner.TryGetFloatRate(fixingDate, underlyingCode, out double r);
+        rate = Convert.ToDecimal(r);
+        return ok;
+    }
+}
diff --git a/YLErpDAL/Modules/SwapModule/SwapDealService.cs b/YLErpDAL/Modules/SwapModule/SwapDealService.cs
index 4183bece..c2a74be4 100644
--- a/YLErpDAL/Modules/SwapModule/SwapDealService.cs
+++ b/YLErpDAL/Modules/SwapModule/SwapDealService.cs
@@ -5,6 +5,7 @@ using System.Linq.Expressions;
 using YLErp.BLL;
 using YLErp.BLL.Eod;
 using YLErp.DBModels.Enums;
+using YLErp.Derivatives.Interest;
 using YLErp.Helpers;
 using YLErp.Modules.DataProviderModule;
 using YLErp.Modules.EodModule;
@@ -23,6 +24,10 @@ namespace YLErp.Modules.SwapModule
             return EodPriceQueryService.TryGetPrice(valueDate, underlyingCode, out rate);
         }
 
+        private IIndexFixer _indexFixer;
+        /// <summary>FR007 取价器，委托 TryGetFloatRate（保留 virtual 接缝供测试 stub）。</summary>
+        protected virtual IIndexFixer IndexFixer => _indexFixer ??= new SwapDealIndexFixer(this);
+
         #region 可测试化接缝（Seams）——override 这些虚方法可在测试中替换 DB/外部调用，生产代码行为不变
 
         // FindTrade 已上提到基类 SwapTradeBaseService（三子类实现一致，消除重复）
@@ -1037,9 +1042,8 @@ namespace YLErp.Modules.SwapModule
             if (string.IsNullOrEmpty(position.FloatRateUnderlyingCode)) return position.FloatRate;
 
             int days = (endDate - startDate).Days;
-            DateTime rateDate = days % period == 0
-                ? QdpCalendarHelper.GetNonHolidayDefore(endDate.AddDays(position.interest_rule ?? 0))
-                : QdpCalendarHelper.GetNonHolidayDefore(startDate.AddDays(position.interest_rule ?? 0));
+            DateTime rateDate = IndexFixerBase.GetFixingDate(
+                days % period == 0 ? endDate : startDate, position.interest_rule);
 
             if (preEod.id != 0 && days % period != 0)
             {
@@ -1047,9 +1051,9 @@ namespace YLErp.Modules.SwapModule
                 return preEod.FloatRate;
             }
 
-            if (TryGetFloatRate(rateDate, position.FloatRateUnderlyingCode, out double rate))
+            if (IndexFixer.TryGetFixing(rateDate, position.FloatRateUnderlyingCode, out decimal rate))
             {
-                position.FloatRate = positionClone.FloatRate = Convert.ToDecimal(rate);
+                position.FloatRate = positionClone.FloatRate = rate;
                 return position.FloatRate;
             }
             if (!swap) throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{rateDate:yyyy年MM月dd日}的价格");
@@ -1352,14 +1356,14 @@ namespace YLErp.Modules.SwapModule
                 if (accrueDate >= startDate && i % interestPeriod == 0
                     && !string.IsNullOrEmpty(position.FloatRateUnderlyingCode))
                 {
-                    var fr007RateDate = QdpCalendarHelper.GetNonHolidayDefore(accrueDate.AddDays(position.interest_rule ?? 0));
-                    if (TryGetFloatRate(fr007RateDate, position.FloatRateUnderlyingCode, out double floatRate1))
+                    var fixingDate = IndexFixerBase.GetFixingDate(accrueDate, position.interest_rule);
+                    if (IndexFixer.TryGetFixing(fixingDate, position.FloatRateUnderlyingCode, out decimal fixing))
                     {
-                        if (floatRate1 != 0) floatRate = floatRate1;
+                        if (fixing != 0m) floatRate = Convert.ToDouble(fixing);
                     }
                     else
                     {
-                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fr007RateDate:yyyy年MM月dd日}的价格");
+                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fixingDate:yyyy年MM月dd日}的价格");
                     }
                 }
                 if (accrueDate >= startDate)
@@ -1443,14 +1447,14 @@ namespace YLErp.Modules.SwapModule
                     // tdDynomicPrincipal = flowEvent.InterestPrincipal 使本金累积乘 closePercent^N）。
                     if (i % interestPeriod == 0 && !string.IsNullOrEmpty(position.FloatRateUnderlyingCode))
                     {
-                        var fr007RateDate = QdpCalendarHelper.GetNonHolidayDefore(accrueDate.AddDays(position.interest_rule ?? 0));
-                        if (TryGetFloatRate(fr007RateDate, position.FloatRateUnderlyingCode, out double floatRate1))
+                        var fixingDate = IndexFixerBase.GetFixingDate(accrueDate, position.interest_rule);
+                        if (IndexFixer.TryGetFixing(fixingDate, position.FloatRateUnderlyingCode, out decimal fixing))
                         {
-                            if (floatRate1 != 0) floatRate = floatRate1;
+                            if (fixing != 0m) floatRate = Convert.ToDouble(fixing);
                         }
                         else
                         {
-                            throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fr007RateDate:yyyy年MM月dd日}的价格");
+                            throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fixingDate:yyyy年MM月dd日}的价格");
                         }
                     }
 
@@ -1507,18 +1511,14 @@ namespace YLErp.Modules.SwapModule
                 tdDynomicPrincipal = tdDynomicPrincipal + interestProfitSum * remainingPercent;
                 if (!string.IsNullOrEmpty(position.FloatRateUnderlyingCode))
                 {
-                    // 获取合适的 rateDate
-                    var fr007RateDate = QdpCalendarHelper.GetNonHolidayDefore(endDate.AddDays(position.interest_rule ?? 0)); // 获取前一工作日;
-                    if (TryGetFloatRate(fr007RateDate, position.FloatRateUnderlyingCode, out double floatRate1))
+                    var fixingDate = IndexFixerBase.GetFixingDate(endDate, position.interest_rule);
+                    if (IndexFixer.TryGetFixing(fixingDate, position.FloatRateUnderlyingCode, out decimal fixing))
                     {
-                        if (floatRate1 != 0)
-                        {
-                            floatRate = floatRate1;
-                        }
+                        if (fixing != 0m) floatRate = Convert.ToDouble(fixing);
                     }
                     else
                     {
-                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fr007RateDate:yyyy年MM月dd日}的价格");
+                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fixingDate:yyyy年MM月dd日}的价格");
                     }
 
                 }
@@ -1572,17 +1572,14 @@ namespace YLErp.Modules.SwapModule
                 // 获取新的浮动利率
                 if (!string.IsNullOrEmpty(position.FloatRateUnderlyingCode))
                 {
-                    var fr007RateDate = QdpCalendarHelper.GetNonHolidayDefore(endDate.AddDays(position.interest_rule ?? 0));
-                    if (TryGetFloatRate(fr007RateDate, position.FloatRateUnderlyingCode, out double newFloatRate))
+                    var fixingDate = IndexFixerBase.GetFixingDate(endDate, position.interest_rule);
+                    if (IndexFixer.TryGetFixing(fixingDate, position.FloatRateUnderlyingCode, out decimal fixing))
                     {
-                        if (newFloatRate != 0)
-                        {
-                            floatRate = newFloatRate;
-                        }
+                        if (fixing != 0m) floatRate = Convert.ToDouble(fixing);
                     }
                     else
                     {
-                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fr007RateDate:yyyy年MM月dd日}的价格");
+                        throw new Exception($"获取不到{position.FloatRateUnderlyingCode}在{fixingDate:yyyy年MM月dd日}的价格");
                     }
                 }
             }