--- a/vendor/magento/module-sales/Model/Order/Pdf/AbstractPdf.php
+++ b/vendor/magento/module-sales/Model/Order/Pdf/AbstractPdf.php
@@ -304,7 +304,7 @@ abstract class AbstractPdf extends \Magento\Framework\DataObject
 
                 $y1 = $top - $height;
                 $y2 = $top;
-                $x1 = 25;
+                $x1 = 290 - ($width / 2);
                 $x2 = $x1 + $width;
 
                 //coordinates after transformation are rounded by Zend
@@ -660,7 +660,7 @@ abstract class AbstractPdf extends \Magento\Framework\DataObject
      */
     public function insertDocumentNumber(\Zend_Pdf_Page $page, $text)
     {
-        $page->setFillColor(new \Zend_Pdf_Color_GrayScale(1));
+        $page->setFillColor(new \Zend_Pdf_Color_GrayScale(0));
         $this->_setFontRegular($page, 10);
         $docHeader = $this->getDocHeaderCoordinates();
         $page->drawText($text, 35, $docHeader[1] - 15, 'UTF-8');
@@ -1038,7 +1038,7 @@ abstract class AbstractPdf extends \Magento\Framework\DataObject
                 $itemsProp['shift'] = $shift;
             }
 
-            if ($this->y - $itemsProp['shift'] < 15) {
+            if ($this->y - $itemsProp['shift'] < 30) {
                 $page = $this->newPage($pageSettings);
             }
             $this->correctLines($lines, $page, $height);