A method for operating a device configured to deliver a liquid includes: a) back-suctioning a liquid situated in a pressure line section counter to a usual delivery direction by at least one pump; b) monitoring at least one operating parameter of the at least one pump during the back-suctioning, the at least one operating parameter being representative of a counterpressure that the at least one pump operates against during the back-suctioning; and c) detecting an increase in the counterpressure, and stopping the back-suctioning.

A filter assembly may include an outer insert and an inner insert. The outer insert having an aperture and a plurality of outer grooves. The outer grooves are formed in a radially outer periphery of the outer insert and are separated from each other and the aperture. The inner insert may be disposed within the aperture. A plurality of inner grooves may be formed in a radially outer periphery of the inner insert. Each of the outer and inner grooves may have a closed axial end and an open axial end.

A device for the suction filtration of fluids, such as urea solutions for exhaust gas after-treatment systems, has a tank (2) storing the fluid, and a filter element (34) arranged in the tank and provided with a filter medium (32) separating the tank contents from a clean-side inner filter cavity (20). The filter cavity extends from the bottom (10) of the tank (2) to a filling level height (28) and corresponds to a part of the filling volume of the tank (2). On the filter cavity (20), a suction connection (22) discharges the cleaned fluid by a suction pressure corresponding to a system operating pressure. The filter element (34) is provided with a filter medium (32), which is air-impermeable if suction pressures are within the range of a low system operating pressure.

An apparatus for providing liquid additive includes a tank for the liquid additive which has at least one heat distribution structure for distributing heat in a first tank section. A delivery unit is inserted into the tank for removing the liquid additive from the tank. The delivery unit includes at least one heating device. The heating device of the delivery unit and the heat distribution structure of the tank are connected to each other by at least one thermal coupling. A method for assembling the apparatus and a motor vehicle having the apparatus are also provided.

A method for operating a device for providing a liquid additive, the device having a delivery path running from a tank to an additive dispensing device, at least one section of the delivery path forming a jacket, includes: delivering the liquid additive from the tank to the additive dispensing device along the delivery path in a delivery direction; stopping the delivery of the liquid additive; at least partially evacuating the section of the delivery path; and forming a thermal insulator in the jacket by the evacuated delivery path.

A filter element (3), in particular an air filter element, for a filter arrangement (1), having a frame (6) that has at least one contact surface (11) for contacting a clamping surface (30) of at least one clamping element (27, 28) of the filter arrangement (1), wherein the at least one contact surface (11) includes straight segments (12, 13, 14) and oblique segments (15, 16) arranged between the straight segments (12, 13, 14), and wherein the straight segments (12, 13, 14) are arranged such that the clamping surface (30) when the latter is displaced relative to the at least on contact surface (11) essentially exclusively contacts the oblique segments (15, 16).

Tank for a liquid solution based on water and urea which is suitable for being combined with a selective catalytic reduction system. The tank comprises: a container including an upper wall; a filling pipe union which is positioned on the upper wall of the container and which is suitable for introducing the liquid solution; a lower opening, from which the liquid solution being introduced passes into the container and which protrudes with respect to the upper wall towards the interior of the container; a closure float which is positioned in the container and which is connected to the lower opening and which is configured so as to raise and close the lower opening once the liquid solution in the container reaches a predetermined level.

An exhaust aftertreatment system for increasing fractional efficiency of diesel or gasoline particulate filters includes a particulate filter that includes a housing and a filter substrate positioned in the housing. The filter substrate is pre-conditioned with an aqueous solution or suspension configured to decompose or evaporate in response to exposure to heat so as to precondition the filter substrate.

A fluid system for a machine includes a tube assembly and a sock filter enveloping the tube assembly. The fluid system also includes a filter protector adjacent to a fastener in the tube assembly and including a first connector fitted with a first tube, a second connector fitted with a second tube, and a wall that arcs between the first connector and the second connector and limits contact between a sock filter enveloping the tube assembly and the fastener.

A urea water tank (11) is provided with a unit insertion opening (12H) that is disposed on a top surface part (12A) of a tank body (12) and opens more largely than an external dimension (D2) of a sensor unit (20), a sensor mounting member (16) that is disposed on the top surface part (12A) of the tank body (12) and closes the unit insertion opening (12H), and a filter which is formed as a tubular body to surround the sensor unit (20), and inserted in the unit insertion opening (12H) of the tank body (12) from a lower end (24A4)-side, and having an upper end (24A3) mounted on the top surface part (12A) of the tank body (12) by using the sensor mounting member (16).