A continuous cleaning installation 1 of a passing strip S includes a tank 2, an aqueous solution 3 inside the tank 2. It also includes at least a roll 4 immerged in the aqueous solution 3, at least an ultrasound emitter 5, a feed for feeding 6 an aqueous solution and emptying 7 the tank. Moreover, it also includes and estimator for estimating 8 the aqueous solution level, a calculator for calculating 9 for each ultrasound emitter 5 its distance to the aqueous solution level and a controller for controlling the power 10 of the at least one ultrasound emitter 5 and at least an impermeable closable opening 11 on at least a lateral side of the tank through which the at least one ultrasound emitter 5 can pass.

The invention concerns a continuous pickling plant (101) for the treatment of metal products (109) in the form of a strip or tube which includes a plurality of acid solution process tanks (102) each divided into a plurality of turbulence cells (114) and a recirculation system of the acid solution. The plant also includes, upstream of the plurality of process tanks (102), a device for heating (124; 126) the metal product (109), namely an induction heating (124) system and/or a tunnel with water sprays (126). A solution with only two pickling tanks (102) is also presented. Devices are described (135; 136; 138, 138a) to increase turbulence in the tanks and to accelerate pickling, e.g. by adding fresh acid (146) in the first tank. The invention also concerns a related pickling process. The invention optimizes the effect of the acid and reduces the residence time of the strip (109) in the plant.

There is provided a liquid removal device that removes liquid attached to a surface of a steel sheet, the device including a slit nozzle that jets gas to the surface of the sheet, the slit nozzle being installed so as to jet gas from a downstream side toward an upstream side in a movement direction of the sheet that moves relatively to the slit nozzle and being configured in a manner that a jet angle θ, a back face inclination angle β, and a back face length L of a nozzle back face of the slit nozzle satisfy, β+θ≥60° and L≥20mm, and a gap h between a jetting port of the slit nozzle and the sheet, a slit width d, and nozzle pressure P.sub.n of the slit nozzle satisfy the following relationship: P.sub.n≥2.0×10.sup.10(h/d).sup.0.6{1/(1+exp(β+θ−58)+1}.sup.−4L.sup.−7.

A pickling facility includes: a pickling tank for storing an acid solution; a conveyance part for continuously conveying a steel plate immersed in the acid solution; a measurement part for measuring at least one parameter which has a correlation with a heat transfer coefficient between the acid solution and a reference surface disposed in the acid solution so as to face the steel plate; and a conveyance speed decision part configured to decide a conveyance speed of the steel plate conveyed by the conveyance part, on the basis of a measurement result of the at least one parameter.

A water-based grinding machine for polishing a surface of a metal strip includes an unwinding wheel, a polishing mechanism, a cleaning mechanism, a drying mechanism and a winding wheel. The polishing mechanism includes a first polishing wheel and a first workbench. The metal strip is drawn from the unwinding wheel into a gap between a polishing wheel and a pad, and then is drawn to the cleaning mechanism. The cleaning mechanism includes a third workbench and a cleaning liquid storage tank. At least one pair of felt wheels is arranged above the third workbench. The metal strip passes through a gap between the at least one pair of felt wheels. An outer circumference of the at least one pair of felt wheels is covered with a wool layer. The cleaning liquid storage tank is provided with a cleaning pipe. The drying mechanism includes an oven.

A pickling facility includes: a pickling tank for storing an acid solution; a conveyance part for continuously conveying a steel plate immersed in the acid solution; a measurement part for measuring at least one parameter which has a correlation with a heat transfer coefficient between the acid solution and a reference surface disposed in the acid solution so as to face the steel plate; and a conveyance speed decision part configured to decide a conveyance speed of the steel plate conveyed by the conveyance part, on the basis of a measurement result of the at least one parameter.

The invention concerns a continuous pickling plant (101) for the treatment of metal products (109) in the form of a strip or tube which includes a plurality of acid solution process tanks (102) each divided into a plurality of turbulence cells (114) and a recirculation system of the acid solution. The plant also includes, upstream of the plurality of process tanks (102), a device for heating (124; 126) the metal product (109), namely an induction heating (124) system and/or a tunnel with water sprays (126). A solution with only two pickling tanks (102) is also presented. Devices are described (135; 136; 138, 138a) to increase turbulence in the tanks and to accelerate pickling, e.g. by adding fresh acid (146) in the first tank. The invention also concerns a related pickling process. The invention optimizes the effect of the acid and reduces the residence time of the strip (109) in the plant.

[Object] To provide a liquid removal device capable of removing liquid on a steel sheet without using wringer rolls and a drier.

[Solution] A liquid removal device that removes liquid attached to a surface of a sheet-like member that moves relatively, the liquid removal device including: a slit nozzle that jets gas to the surface of the sheet-like member; and a gap measurement device that measures a gap between a jetting port of the slit nozzle and the sheet-like member. The slit nozzle is installed so as to jet gas from a downstream side toward an upstream side in a movement direction of the sheet-like member that moves relatively to the slit nozzle, and is configured in a manner that a jet angle , a back face inclination angle , a back face length L of a nozzle back face, a gap h, a slit width d, and nozzle pressure P.sub.n of the slit nozzle satisfy the following relational formulas.

[00001]$\begin{array}{cc}{P}_{n}2.0{10}^{10}.Math.{\left(h.Math.\text{/}.Math.d\right)}^{0.6}.Math.{\left(\frac{1}{1+\exp \left(+-58\right)}+1\right)}^{-4}.Math.L^{-7},+60.Math.,L20.Math..Math.\mathrm{mm}& \left[\mathrm{Math}..Math.1\right]\end{array}$