Double Stitch In Tubular Crochet

In the graphic, and photo are displayed how to make the union of Double Crochet, closing the row with a Slip stitch stung in the first Double Crochet of the row so that in this way remains in tubular form and the bond line is straight and not oblique as many of you happens.

This technique is widely used for circular crocheting projects such as caps, hats, bottles, etc. You begin to work as follows:

Work a chain base and 1 s.t stung on 1° ch to make a ring.

1° r: 3 ch to replace 1° d.c. Then, 1 d.c stung on each next ch. Finish the r. with 1 s.t. stung on 3°ch counting from the bottom

2°r: 3 ch and 1 d.c stung on each next d.c. Finish the r. with 1 s.t. stung on 3° ch counting from the bottom

Then, rep 2° r. all the time.

References:
-ch.: Chain Stitch
-rep: Repeat
-r: Row
-d.c: Double Crochet
-s.t.: Slip Stitch