diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/RangeExpression.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/RangeExpression.php
index cbcb706d76..5e85715087 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/RangeExpression.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/AST/RangeExpression.php
@@ -12,6 +12,26 @@ class RangeExpression extends Node
     private $higher_bound;
     private $higher_inclusive;
 
+    public static function lessThan(Field $field, $bound)
+    {
+        return new self($field, $bound, false);
+    }
+
+    public static function lessThanOrEqual(Field $field, $bound)
+    {
+        return new self($field, $bound, true);
+    }
+
+    public static function greaterThan(Field $field, $bound)
+    {
+        return new self($field, null, null, $bound, false);
+    }
+
+    public static function greaterThanOrEqual(Field $field, $bound)
+    {
+        return new self($field, null, null, $bound, true);
+    }
+
     public function __construct(Field $field, $lb, $li = false, $hb = null, $hi = false)
     {
         $this->field = $field;
diff --git a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
index 1e21ca764e..bebacaee6f 100644
--- a/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
+++ b/lib/Alchemy/Phrasea/SearchEngine/Elastic/Search/QueryVisitor.php
@@ -137,13 +137,13 @@ class QueryVisitor implements Visit
 
         switch ($node->getId()) {
             case NodeTypes::LT_EXPR:
-                return new AST\RangeExpression($field, $expression, false);
+                return AST\RangeExpression::lessThan($field, $expression);
             case NodeTypes::LTE_EXPR:
-                return new AST\RangeExpression($field, $expression, true);
+                return AST\RangeExpression::lessThanOrEqual($field, $expression);
             case NodeTypes::GT_EXPR:
-                return new AST\RangeExpression($field, null, null, $expression, false);
+                return AST\RangeExpression::greaterThan($field, $expression);
             case NodeTypes::GTE_EXPR:
-                return new AST\RangeExpression($field, null, null, $expression, true);
+                return AST\RangeExpression::greaterThanOrEqual($field, $expression);
         }
     }