A method for monitoring a flame cutting process includes a preheating phase, a piercing phase following the preheating phase and a cutting phase following the piercing phase, wherein a cutting torch applies a flame generated by combustion of a gas mixture to an electrically conductive workpiece and wherein an electric current flowing between an electrically conductive part of the cutting torch and the workpiece is measured by a current measuring device during a measuring period. An ignition point at which piercing of a hole through the workpiece using the flame starts due to oxidation of the workpiece is detected by a change in the measured current.

Cutting torch guide structures, systems, and kits include a base structure having a bottom surface and a channel formed in the base structure, a mechanically switched permanent magnet coupled to the base structure and configured to mechanically switch between two magnetic states, and a cutting torch guide structure configured to be releasably received in the channel and magnetically coupled to the base structure by magnetic attraction between a at least one permanent magnet fixed in at least one recess in the channel and a guide structure permanent magnet fixed to the cutting torch guide structure, where the cutting torch guide structure is configured with a first portion that is removable received in the channel of the base structure and a second portion that overhangs the base structure and includes an edge that defines a predefined shape and is configured to be in slidable contact with a cutting torch tip.

A portable device for precision plasma and oxy-fuel torch cutting is provided. Versions of an example portable cutting torch tool guide the gun of a cutting torch to make precision linear cuts or curved cuts in a metal workpiece. In an implementation, the device is a gun for a cutting torch, with an integrated rail follower and adjustable vertical and horizontal offsets from a workpiece. The cutting torch tool may use various kinds of rails for stable cuts, with optional movement damping, motorized drive, servos for vertical and horizontal offset, and remote control with user interface.

An automated oxy-fuel thermal processing system including an oxy-fuel torch, an automated machine tool operatively coupled to the torch for moving the torch relative to a work piece, and a circuit including a voltage source or a current electrically connected to the torch and configured to be electrically connected to the work piece. The automated oxy-fuel thermal processing system may further include a processor that is operatively connected to the torch, the automated machine tool, the circuit, and the voltage source or current source, wherein the processor is configured to control the operation of the torch, the automated machine tool and the voltage source or current source, and to monitor a current or voltage in the circuit in a predefined manner.

Methods for forming pierce holes in a metal workpiece are disclosed. According to one implementation, upon a plasma torch be energized, the cutting axis of the torch is rotated repeatedly between first and second angular positions to produce successively deeper pierces in a workpiece until a pierce hole is produced through a thickness of the workpiece. According to other implementations pierce holes are produced by rotating the cutting axis of the plasma torch tip around a designated central axis of the pierce hole in a diametrically reducing manner so that the produced pierce hole has a tapered profile with a cross-sectional area of the pierce hole at a top surface of the workpiece being greater than a cross-sectional area of the pierced hole at a bottom surface of the workpiece.

A method for monitoring a flame cutting process includes a preheating phase, a piercing phase following the preheating phase and a cutting phase following the piercing phase, wherein a cutting torch applies a flame generated by combustion of a gas mixture to an electrically conductive workpiece and wherein an electric current flowing between an electrically conductive part of the cutting torch and the workpiece is measured by a current measuring device during a measuring period. An ignition point at which piercing of a hole through the workpiece using the flame starts due to oxidation of the workpiece is detected by a change in the measured current.

Automated systems and methods for making cuts in large materials, particularly to trim and reduce the sizes of steel plates and slabs and produce therefrom one or more reduced-size pieces, optionally with the ability to reduce or avoid the need to perform a separate deburring operation on the materials after undergoing such cuts. Such a system includes multiple support units aligned in a longitudinal direction of a foundation and longitudinal and cross cutting units translatable in the longitudinal direction for performing, respectively, longitudinal and lateral cuts in a material. The support units are independently translatable in the longitudinal direction and each support unit has a crossmember that extends in the lateral direction, is adapted to at least partially support the material, and is operable to be raised and lowered in the vertical direction while the material is supported by the crossmembers.

A method of sensing and initializing a zero-height for a computer-controlled cutting machine implements ohmic contact between a tool head of the cutting machine and a work surface of the cutting machine in order to ascertain a zero-height of the tool head before executing a machine control operation, ensuring the tool head is positioned correctly at a predetermined operating height above the work surface throughout the machine control operation. A baseline electrical resistance is tracked across the work surface. A downward movement of the tool head toward the work surface is executed with a gantry-style movement mechanism of the cutting machine. The downward movement is stopped and a current height of the tool head is designated as the zero-height if a change in the baseline electrical resistance is detected. The tool head is electrically isolated in order to facilitate detection of the change in resistance.

A portable device for precision plasma and oxy-fuel torch cutting is provided. Versions of an example portable cutting torch tool guide the gun of a cutting torch to make precision linear cuts or curved cuts in a metal workpiece. In an implementation, the device is a gun for a cutting torch, with an integrated rail follower and adjustable vertical and horizontal offsets from a workpiece. The cutting torch tool may use various kinds of rails for stable cuts, with optional movement damping, motorized drive, servos for vertical and horizontal offset, and remote control with user interface.

Methods for forming pierce holes in a metal workpiece are disclosed. According to one implementation, upon a plasma torch be energized, the cutting axis of the torch is rotated repeatedly between first and second angular positions to produce successively deeper pierces in a workpiece until a pierce hole is produced through a thickness of the workpiece. According to other implementations pierce holes are produced by rotating the cutting axis of the plasma torch tip around a designated central axis of the pierce hole in a diametrically reducing manner so that the produced pierce hole has a tapered profile with a cross-sectional area of the pierce hole at a top surface of the workpiece being greater than a cross-sectional area of the pierced hole at a bottom surface of the workpiece.