Choose Features tab→Assembly Features group→Groove Weld 
.
Click the Groove Weld Options button, then on the Groove Weld Options dialog box, define the weld symbol attributes.
Click the base face(s), then click the Accept (checkmark) button.
Click the target face(s), then click the Accept (checkmark) button.
Click the edges that define the top-path on the target side of the weld, then click the Accept button.
Click the edges that define the bottom-path on the target side of the weld, then click the Accept button.
On the command bar, click the Preview button.
Tip:
Some groove welds require that you also define base top-path and bottom-path edges.
Groove weld features are not combined with the parts they touch, and do not modify the input parts.
You can use the material removal commands, such as cutout, hole, and revolved cutout to modify a groove weld feature.
You can use the commands on the shortcut menu to edit, delete, suppress, and rename groove weld features.