A method for desulfurizing molten steel comprising taking a sample out from molten steel after tapping from a converter or during secondary refining and analyzing the sample rapidly with high accuracy by a method comprising a high frequency induction heating step wherein the sample is combusted and oxidized under the high frequency induction heating in an oxygen atmosphere having an oxygen purity of 99.5 vol % or more to convert S in the sample into SO.sub.2 and an analyzing step wherein SO.sub.2-containing gas produced in the high frequency induction heating step is analyzed through an ultraviolet fluorescence method to quantify S concentration of the sample.

A control unit can select a large-number control zone model in which the number of control zones, which are independently controlled, is large, and a small-number control zone model in which the number of control zones, which are independently controlled, is small. When a temperature is increased or decreased, the control unit can select the small-number control zone model so as to control, based on signals from temperature sensors of the respective control zones C1 . . . C5 whose number is small, heaters located on the respective control zones C1 . . . C5. When a temperature is stabilized, the control unit can select the large-number control zone model so as to control, based on signals signals from the temperature sensors of the respective control zones C1 . . . C10 whose number is large, the heaters located on the respective control zones C1 . . . C10.

An apparatus for detecting ground faults in a multifurnace installation with at least two induction furnaces and a multifurnace installation are described. A ground-fault sensor is associated with each induction furnace and is connected to the electrical supply line to the induction furnace coil. Furthermore, the apparatus has a ground-leak sensor. Moreover, the apparatus includes an additional ground-fault sensor that measures at the same location as the ground-leak sensor. In this manner an improvement of security during the operation of the system is obtained.

An apparatus for detecting ground faults in a multifurnace installation with at least two induction furnaces and a multifurnace installation are described. A ground-fault sensor is associated with each induction furnace and is connected to the electrical supply line to the induction furnace coil. Furthermore, the apparatus has a ground-leak sensor. Moreover, the apparatus includes an additional ground-fault sensor that measures at the same location as the ground-leak sensor. In this manner an improvement of security during the operation of the system is obtained.

The invention relates to a melting apparatus (100) for melting paraffin (1), having: a melting container (110) for receiving paraffin (1) to be melted; a storage container (190) for storing molten paraffin (4); having a melting container heating device (120) for heating the melting container (110), having a storage container heating device (191) for heating the storage container (190), having a fluid connection (113) fluidically connecting the melting container (110) and the storage container; the melting container (110), the storage container (190), and the fluid connection (113) being arranged so that molten paraffin (4) flows out of the melting container (110) into the storage container (190).

Magnetic field components are measured at multiple longitudinal positions and used to calculate estimated longitudinal position and length of a transversely localized electric current segment flowing across a gap between conductive bodies. The apparatus can be used with a remelting furnace. The electrode and ingot act as the conductive bodies, and arcs, discharges, or slag currents are the current segments spanning the gap. Actuators for movable sensors can be coupled to the sensors in a servomechanism arrangement to move the sensors along with the moving gap. An actuator for moving one of the conductive bodies can be coupled to sensors in a servomechanism arrangement to maintain the gap distance within a selected range as the gap moves.

Disclosed herein is a monitoring system including a detecting device configured to detect at least one of smoke and heat, an alarm in operable communication with the detecting device, wherein the alarm is configured to notify a user after the detecting device detects at least one of smoke and heat, a sensing structure configured to determine whether a heating apparatus has a temperature that is above a threshold, and a processor in operable communication with the sensing structure and at least one of the detecting device and the alarm, the processor configured to at least one of turn off at least one of the alarm and the detecting device; and reduce the sensitivity of the detecting device, when the sensing structure determines that the heating apparatus has a temperature that is above a threshold.

The invention relates to a dental furnace, in particular a firing furnace or press furnace, for firing or pressing a dental restoration part which is receivable in the furnace, possibly after pre-heating in a pre-heating furnace, and which is placeable on a base, in particular centrally thereon, wherein the dental furnace comprises a firing chamber whose diameter is larger than, in particular at least twice as large as, the largest dental restoration part to be fired, and which comprises a control device and an operating unit at the or for the dental furnace (10), wherein by means of the operating unit (26) the size and/or the weight and/or the number of the dental restoration part(s) (18) to be fired or pressed is adjustable in units.

The invention relates to a dental furnace, in particular a firing furnace or press furnace, for firing or pressing a dental restoration part which is receivable in the furnace, possibly after pre-heating in a pre-heating furnace, and which is placeable on a base, in particular centrally thereon, wherein the dental furnace comprises a firing chamber whose diameter is larger than, in particular at least twice as large as, the largest dental restoration part to be fired, and which comprises a control device and an operating unit at the or for the dental furnace (10), wherein by means of the operating unit (26) the size and/or the weight and/or the number of the dental restoration part(s) (18) to be fired or pressed is adjustable in units.

A cooling plate for a metallurgical furnace comprising a body (12) with a front face (18) and an opposite rear face (20), the body having at least one coolant channel (14) therein; the front face (18) being turned towards the furnace interior and preferably comprises alternating ribs (22) and grooves (24). The cooling plate includes wear detection means comprising: a plurality of closed pressure chambers (26, 28) distributed at different locations in said body, said pressure chambers being positioned at predetermined depths below the front face (18) of said body; and a pressure sensor (30) associated with each pressure chamber (26, 28) in order to detect a deviation from a reference pressure inside said pressure chamber when the latter becomes open due to wear out of said body.