The invention relates to a method and to a delivery apparatus for carrying out the method, wherein the delivery apparatus comprises an eccentric screw pump having a rotor-stator unit with an outlet, a drive unit, a control device and a delivery section, and wherein the delivery apparatus comprises at least one pressure sensor and a characteristic-variable detection device.

A method to manufacture a tubular element for transferring abrasive materials such as concrete, inert materials or suchlike, wherein the tubular element comprises an internal tubular component made of chromium carbide or other wear-resistant material, and an internal tubular component in contact with and coaxial to the internal tubular component and made of composite material.

A method to manufacture a tubular element for transferring abrasive materials such as concrete, inert materials or suchlike, wherein the tubular element comprises an internal tubular component made of chromium carbide or other wear-resistant material, and an internal tubular component in contact with and coaxial to the internal tubular component and made of composite material.

A method to make a tubular element to transfer abrasive materials such as concrete, inert materials or suchlike, where the tubular element includes an external tubular component made of steel and an internal tubular component, coaxial to the external tubular component, where the internal tubular component is made of chromium carbide, or other similar material resistant to wear.

A two-branch or multi-branch double-layer wear-and-impact-resistant tube and manufacturing method thereof. The wear-and-impact-resistant tube comprises an outer protective tube and an inner wear-resistant assembled tube nested in the outer protective tube. The inner wear-resistant assembled tube comprises two or more tube walls, the two or more tube walls are jointed to form a tube having an annular cross section. The wear-and-impact-resistant tube can be a straight tube or a bent tube. If the wear-and-impact-resistant tube is a straight tube, upper and lower portions of the inner wear-resistant assembled tube employ different structures, and if the wear-and-impact-resistant tube is a bent tube, a large curved portion and a small curved portion of the bent tube employ different structures. The inner assembled tube of the wear-and-impact-resistant tube is divided into at least two portions, and the at least two portions thereof employ different structures. The tube structure extends a service life thereof, improves wear resistance and impact resistance thereof, and reduces a total weight of the tube.

Method and apparatus for producing a curved tubular segment comprising obtaining a curved external tubular element and a curved internal tubular element made of a material having a resistance to wear greater than that of the curved external tubular element and having a cross section such as to cover at least part of the internal surface of the curved external tubular element. It provides the insertion of the curved internal tubular element inside the curved external tubular element after heating the latter by means of a heating unit. Moreover, to form the curved external tubular element on the exact geometry of the curved internal tubular element a molding unit and a cooling unit are used to obtain a curved tubular segment without spaces between the curved external tubular element and the curved internal tubular element.

Method and apparatus for producing a curved tubular segment comprising obtaining a curved external tubular element and a curved internal tubular element made of a material having a resistance to wear greater than that of the curved external tubular element and having a cross section such as to cover at least part of the internal surface of the curved external tubular element. It provides the insertion of the curved internal tubular element inside the curved external tubular element after heating the latter by means of a heating unit. Moreover, to form the curved external tubular element on the exact geometry of the curved internal tubular element a molding unit and a cooling unit are used to obtain a curved tubular segment without spaces between the curved external tubular element and the curved internal tubular element.