diff --git a/ApplicationLibCode/ProjectDataModel/Jobs/RimKeywordFactory.cpp b/ApplicationLibCode/ProjectDataModel/Jobs/RimKeywordFactory.cpp
index e39aa14013..754d4e20f2 100644
--- a/ApplicationLibCode/ProjectDataModel/Jobs/RimKeywordFactory.cpp
+++ b/ApplicationLibCode/ProjectDataModel/Jobs/RimKeywordFactory.cpp
@@ -836,6 +836,54 @@ namespace
         }
         return result;
     }
+
+    //--------------------------------------------------------------------------------------------------
+    /// Shorten a parser item name to at most maxWidth characters so long names (e.g.
+    /// "CONNECTION_TRANSMISSIBILITY_FACTOR") do not widen their column beyond the data. Each
+    /// underscore-separated token is truncated to progressively shorter prefixes ("CONN_TRAN_FACT",
+    /// "CON_TRA_FAC", ...), falling back to token initials ("CTF") and finally a hard cut.
+    //--------------------------------------------------------------------------------------------------
+    std::string shortenItemName( const std::string& name, size_t maxWidth )
+    {
+        if ( name.size() <= maxWidth ) return name;
+
+        std::vector<std::string> tokens;
+        std::stringstream        tokenStream( name );
+        std::string              token;
+        while ( std::getline( tokenStream, token, '_' ) )
+        {
+            if ( !token.empty() ) tokens.push_back( token );
+        }
+        if ( tokens.empty() ) return name.substr( 0, maxWidth );
+
+        auto joinPrefixes = [&tokens]( size_t prefixLength )
+        {
+            std::string joined;
+            for ( const auto& t : tokens )
+            {
+                if ( !joined.empty() ) joined += "_";
+                joined += t.substr( 0, prefixLength );
+            }
+            return joined;
+        };
+
+        size_t longestToken = 0;
+        for ( const auto& t : tokens )
+            longestToken = std::max( longestToken, t.size() );
+
+        for ( size_t prefixLength = longestToken - 1; prefixLength >= 2; --prefixLength )
+        {
+            std::string candidate = joinPrefixes( prefixLength );
+            if ( candidate.size() <= maxWidth ) return candidate;
+        }
+
+        std::string initials;
+        for ( const auto& t : tokens )
+            initials += t.front();
+        if ( initials.size() <= maxWidth ) return initials;
+
+        return name.substr( 0, maxWidth );
+    }
 } // namespace
 
 //--------------------------------------------------------------------------------------------------
@@ -897,12 +945,21 @@ QString deckKeywordToAlignedString( const Opm::DeckKeyword& keyword )
 
         const size_t        numCols = header.size();
         std::vector<size_t> width( numCols, 0 );
-        for ( size_t c = 0; c < numCols; ++c )
-            width[c] = header[c].size();
         for ( const auto& row : rows )
             for ( size_t c = 0; c < numCols; ++c )
                 width[c] = std::max( width[c], row[c].size() );
 
+        // Long parser item names (e.g. "CONNECTION_TRANSMISSIBILITY_FACTOR") would otherwise pad
+        // every data row to the header width and push lines past the 132-character limit enforced
+        // by some simulators. Shorten each header to the width of its data, letting narrow columns
+        // grow to a small minimum so the abbreviations stay readable.
+        constexpr size_t minHeaderWidth = 8;
+        for ( size_t c = 0; c < numCols; ++c )
+        {
+            header[c] = shortenItemName( header[c], std::max( width[c], minHeaderWidth ) );
+            width[c]  = std::max( width[c], header[c].size() );
+        }
+
         // Header comment line: "--" occupies the same two columns as the data-row indent so the
         // header names line up with the values below them.
         if ( numCols > 0 )
diff --git a/ApplicationLibCode/UnitTests/RifOpmFlowDeckFile-Test.cpp b/ApplicationLibCode/UnitTests/RifOpmFlowDeckFile-Test.cpp
index 1accd05b3a..f9c76fb2e1 100644
--- a/ApplicationLibCode/UnitTests/RifOpmFlowDeckFile-Test.cpp
+++ b/ApplicationLibCode/UnitTests/RifOpmFlowDeckFile-Test.cpp
@@ -15,6 +15,7 @@
 #include "opm/input/eclipse/Deck/DeckKeyword.hpp"
 #include "opm/input/eclipse/Deck/DeckRecord.hpp"
 #include "opm/input/eclipse/Parser/ParserKeywords/B.hpp"
+#include "opm/input/eclipse/Parser/ParserKeywords/C.hpp"
 
 #include <QDebug>
 #include <QDir>
@@ -575,3 +576,39 @@ TEST( RifOpmFlowDeckFileTest, RemoveAndInsertKeywordAtSectionStart )
     ASSERT_NE( nextIt, keywords.end() );
     EXPECT_EQ( "BCPROP", *nextIt ) << "BCPROP should be the first keyword inside SCHEDULE";
 }
+
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+TEST( RimKeywordFactoryTest, DeckKeywordToAlignedStringShortensLongHeaders )
+{
+    using C = Opm::ParserKeywords::COMPDAT;
+
+    Opm::DeckKeyword kw( ( Opm::ParserKeywords::COMPDAT() ) );
+
+    std::vector<Opm::DeckItem> items;
+    items.push_back( RifOpmDeckTools::item( C::WELL::itemName, std::string( "WELL-1" ) ) );
+    items.push_back( RifOpmDeckTools::item( C::I::itemName, 12 ) );
+    items.push_back( RifOpmDeckTools::item( C::J::itemName, 34 ) );
+    items.push_back( RifOpmDeckTools::item( C::K1::itemName, 5 ) );
+    items.push_back( RifOpmDeckTools::item( C::K2::itemName, 7 ) );
+    items.push_back( RifOpmDeckTools::item( C::STATE::itemName, std::string( "OPEN" ) ) );
+    items.push_back( RifOpmDeckTools::defaultItem( C::SAT_TABLE::itemName ) );
+    items.push_back( RifOpmDeckTools::item( C::CONNECTION_TRANSMISSIBILITY_FACTOR::itemName, 0.1234567891 ) );
+    items.push_back( RifOpmDeckTools::item( C::DIAMETER::itemName, 0.216 ) );
+    items.push_back( RifOpmDeckTools::defaultItem( C::Kh::itemName ) );
+    items.push_back( RifOpmDeckTools::item( C::SKIN::itemName, 0.0 ) );
+    items.push_back( RifOpmDeckTools::defaultItem( C::D_FACTOR::itemName ) );
+    items.push_back( RifOpmDeckTools::item( C::DIR::itemName, std::string( "Z" ) ) );
+    kw.addRecord( Opm::DeckRecord{ std::move( items ) } );
+
+    QString text = RimKeywordFactory::deckKeywordToAlignedString( kw );
+
+    // Long parser item names must be abbreviated so they do not widen the columns (issue #14136).
+    EXPECT_FALSE( text.contains( "CONNECTION_TRANSMISSIBILITY_FACTOR" ) );
+
+    for ( const QString& line : text.split( '\n' ) )
+    {
+        EXPECT_LE( line.size(), 132 ) << "Line exceeds 132 characters: " << line.toStdString();
+    }
+}