For orders you will usually need customers as well.

I used this [answer][1] as reference when I first did this 

You want to only run the `bin/magento data:migrate` command. With `-r` if you want to start afresh.

In your `config.xml`, comment out the `Eav` and other steps you want to exclude:

    <steps mode="data">
            <step title="Data Integrity Step">
                <integrity>Migration\Step\DataIntegrity\Integrity</integrity>
            </step>
            <!--<step title="EAV Step">
                <integrity>Migration\Step\Eav\Integrity</integrity>
                <data>Migration\Step\Eav\Data</data>
                <volume>Migration\Step\Eav\Volume</volume>
            </step>-->
            <step title="Customer Attributes Step">
                <integrity>Migration\Step\Customer\Integrity</integrity>
                <data>Migration\Step\Customer\Data</data>
                <volume>Migration\Step\Customer\Volume</volume>
            </step>
            <step title="Map Step">
                <integrity>Migration\Step\Map\Integrity</integrity>
                <data>Migration\Step\Map\Data</data>
                <volume>Migration\Step\Map\Volume</volume>
            </step>
            <!--<step title="Url Rewrite Step">
                <integrity>Migration\Step\UrlRewrite\Version191to2000</integrity>
                <data>Migration\Step\UrlRewrite\Version191to2000</data>
                <volume>Migration\Step\UrlRewrite\Version191to2000</volume>
            </step>-->
            <step title="Log Step">
                <integrity>Migration\Step\Log\Integrity</integrity>
                <data>Migration\Step\Log\Data</data>
                <volume>Migration\Step\Log\Volume</volume>
            </step>
            <step title="Ratings Step">
                <integrity>Migration\Step\Ratings\Integrity</integrity>
                <data>Migration\Step\Ratings\Data</data>
                <volume>Migration\Step\Ratings\Volume</volume>
            </step>
            <!--<step title="ConfigurablePrices step">
                <integrity>Migration\Step\ConfigurablePrices\Integrity</integrity>
                <data>Migration\Step\ConfigurablePrices\Data</data>
                <volume>Migration\Step\ConfigurablePrices\Volume</volume>
            </step>-->
            <step title="OrderGrids Step">
                <integrity>Migration\Step\OrderGrids\Integrity</integrity>
                <data>Migration\Step\OrderGrids\Data</data>
                <volume>Migration\Step\OrderGrids\Volume</volume>
            </step>
            <!--<step title="Tier Price Step">
                <integrity>Migration\Step\TierPrice\Integrity</integrity>
                <data>Migration\Step\TierPrice\Data</data>
                <volume>Migration\Step\TierPrice\Volume</volume>
            </step>-->
            <step title="SalesIncrement Step">
                <integrity>Migration\Step\SalesIncrement\Integrity</integrity>
                <data>Migration\Step\SalesIncrement\Data</data>
                <volume>Migration\Step\SalesIncrement\Volume</volume>
            </step>
            <!--<step title="PostProcessing Step">
                <data>Migration\Step\PostProcessing\Data</data>
            </step>-->
        </steps>

Then in your `map.xml` ignore most product stuff with:

         

             <ignore>
                 <document>catalog_category*</document>
             </ignore>
             <ignore>
                 <document>catalog_compare*</document>
             </ignore>
             <ignore>
                 <document>catalog_eav_attribute</document>
             </ignore>
             <ignore>
                 <document>cataloginventory_stock*</document>
             </ignore>
             <ignore>
                 <document>catalog_product_*</document>
             </ignore>
             <ignore>
                 <document>core_*</document>
             </ignore>
             <ignore>
                 <document>cms_*</document>
             </ignore>

  [1]: https://magento.stackexchange.com/questions/134046/migrate-orders-from-magento-1-9-to-2-using-the-magento-data-migration-tool/134326