The irrigation matter (1) of the present invention is inserted and welded in the interior of a drip irrigation pipe (2) during production thereof. It has a number of protrusions (8) arranged in a row emerging from a solid flat part/base (6) of the outer convex surface (7) of the emitter (1). The pipe (2) is locally swollen, covers and is welded both on the protrusions (8) and on their base (6), so that a unified welded assembly is formed between protrusions (8) and the pipe. The water outlets (10) are typically and preferably formed between the prismatic protrusions (8) by cutting off the tips of the protrusions (8) during passage of the drip irrigation pipe in a continuously rotating concave fraise (35) located at the end of the production line. Cutting takes place after the pipe has passed through a system of successive pairs of concave and convex rollers which squeeze it, stretch it and make it rigid, maintaining it in a flattened convex and bent form.
