class MyUploader{
  private $var1 = null;
  private $var2 = null;
  private $extensions = array(
    0 => array("pdf","doc","docx")
    ,1 => array("dft","dxf","dwg")
    ,2 => array("step","igs","x_t")
  );
  [etc...]

  function __construct(){
    $this->var1 = 'value1';
    $this->var2 = 'value2';
    [etc...]
  }

  function store_file(){}
  function remove_file(){}
}

$uploaders = array(
   'ul1' => new Uploader()
   'ul2' => new Uploader()
   etc..
);

$uploaders[ul1]->store_file()