File is not getting saved using paperclip

Hi all I have a form which contains attachments but the attachment is not getting created in file system and the fields for the attachment in DB is not getting filled when a new form is created .

I'm using paperclip

I hope the problem is with view part html=>:multipart (as I'm using a single form to create multiple instances)

My Controller:

def create   @ins=params[:ins].values.collect{|ins|}     respond_to do |format|     if @ins.all?(&:valid?)       @ins.each(&:save!)

     format.html { redirect_to :action => 'index'}     else

        format.html {render :action => 'new'}

     end end

def new      @ins ={} end

  My view:

<%= form_tag({:action => :create}, {:multipart => true}) %>    <% @ins.each_with_index do |ins, index| %>     <% fields_for "ins[#{index}]", ins do |f| %>         <%= f.text_field :pol_number%>        <%= f.file_field :attachment%>     <% end %>      <br/>      <% end %>         <%= submit_tag "Save"%> </form>

My Model:

class InsPol < ActiveRecord::Base has_attached_file :attachment


Moreover i have All the db migration for this attachment using paperclip and paperclip installed properly

Plz help me in this regard