Abstract: An internal combustion rotary engine comprises: at least one combustion chamber; a flywheel; at least one piston provided in said flywheel; two or more barrier elements; a circumferential volume between the outer surface of said flywheel, the housing of said flywheel, and two or more barrier elements; wherein some parts of the circumferential volume are also delimited by one or more pistons, and wherein the barrier elements are adapted to be positioned within said circumferential volume thereby to essentially block the flow of air therein, and to be positioned such as to at least partially unblock the flow of air therein, thereby allowing said air flow to take place, and to be positioned such as to be totally open to promote the piston to move between circumferential area and wherein the timing of movement of the barrier elements is dependent from the rotation of said flywheel and/or the location of said piston(s); and wherein the barrier element that is in contact with a portion of pressurized air is adapted

Abstract: An apparatus enables forming extruded plastic material into a strip that may be formed into an irrigation pipe. The apparatus includes a pair of juxtaposed rollers which when rotated, the linear velocity of a contact surface of one of the rollers of the pair is different from the linear velocity of a contact surface of the other roller of the pair. Thus, extruded material that passes between the rollers is concurrently stretched and flattened.

Abstract: An apparatus enables forming extruded plastic material into a strip that may be formed into an irrigation pipe. The apparatus includes a pair of juxtaposed rollers which when rotated, the linear velocity of a contact surface of one of the rollers of the pair is different from the linear velocity of a contact surface of the other roller of the pair. Thus, extruded material that passes between the rollers is concurrently stretched and flattened.