Abstract: The method for covering an object to be coated (40) with a meltable covering comprises the following steps: establishment of a flame (44), the direction of the flame (F) thereof being oriented towards the object to be coated and introduction of an amount of meltable covering material into the flame. The temperature of the flame is sufficiently high in order to result in the at least partial melting of the meltable material. The speed of the flame is chosen in such a way that the meltable covering material thus melted is projected onto the object to be coated. At least one part of the amount of meltable coating material is in a melted stated when it impacts upon the object to be coated. The amount of meltable covering material includes powder. The invention can be used for coating cast iron pipes.

Abstract: The invention relates to a device for positioning a die block (5) of a casting table (1) of a continuous vertical ascendant casting machine for pipes (T) with respect to a vertical axis of extraction (X—X), the die block (5) of the machine being fed by means of a device (3) for the supply of liquid iron, and bearing thereon.

Abstract: A plant for metallization of a metal pipe obtained by upward vertical continuous casting and displaced vertically in a continuous manner, includes, along the path of the pipe, a metallization station having a passage for the pipe, a metallization enclosure (6), spray guns (11) mounted inside the enclosure on an oscillating plate (10) surrounding the path, means for supplying each gun with metallization material (12), and a device for causing oscillation of the support plate and for displacing the guns inside the enclosure with an oscillating movement, the frequency and angular amplitude of which ensure the formation of a coating of uniform thickness.

Abstract: A sealing device for a casting table of a machine for the continuous vertical casting along a vertical extraction axis (X—X) of cast iron pipes (T) includes a die block (5) aligned with the vertical extraction axis and a device (3) for the supply of liquid iron. Two sealing gaskets (12A, 12B) are located between the outlet from the device supplying liquid iron and the entry to the die block. The sealing device has members (6, 15, 21) for tightening the die block against the outlet of the supply device, parallel to the vertical extraction axis, in order to tighten the sealing gaskets.

Abstract: A speed control method for controlling an electric motor by varying the supply duration of the motor, comprises the steps of:initially storing, for a constant speed to be obtained, the curve of the current in the motor as a function of the supply duration;selecting a supply duration;measuring the resulting current in the motor; andcorrecting the supply duration so that the point defined by the supply duration and the resulting measured current converges towards a point of the curve.

Abstract: A method for controlling a valve including a direct current motor acting upon an aperture adjusting part (3) against the force of elastic means (11) biasing the aperture adjusting part towards a zero flow rest position, comprising the steps of: selecting a desired valve aperture; determining a time interval (T.sub.a) as a function of the desired valve aperture; supplying the motor with a first constant current of a sufficient value for rotating the motor, during the mentioned time interval; supplying the motor with a second constant low value current thereafter until a next valve aperture is selected, this low value current being sufficient to hold the motor in its position against the force of the elastic means.

Abstract: A synchronous motor is divulged whose direction of rotation may be chosen, comprising a rotor with permanent magnet and a stator with homopolar field, including a winding fed with an AC voltage. In response to a stopping order, a circuit controls the switch for opening the connection of the winding when the voltage is decreasing in absolute value or is cancelled out and stores the sign of its slope at the time of opening. The circuit controls the switch for closing the connection when the voltage is cancelled out or is increasing in absolute value, with a sign slope identical to, respectively opposite, the stored sign, in accordance with an order for setting in rotation in a direction identical to, respectively opposite, the preceding direction of rotation.