Torch with integral flashback arrestor and thermal shut-off device

Abstract

A torch with integral flashback arrestor and thermal shut-off device is provided. In one approach, a torch body includes a passageway of the torch body, and a cartridge assembly disposed within the passageway. The cartridge assembly may include at least one of: a resettable pressure-sensitive device, and a thermal shut-off device, wherein the pressure-sensitive device and the thermal shut-off device are modifiable from a first configuration to a second configuration in response to a pressure or temperature gradient in the torch body, and wherein the second configuration restricts flow through the passageway. The cartridge may further include a check valve disposed along the passageway, for example, within a bore of a bushing, or within a retainer coupled to the torch body at an inlet of the passageway.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation of International Application No. PCT / US2016 / 069392, filed on Dec. 30, 2016, the entire contents of which is hereby incorporated by reference.BACKGROUND OF THE DISCLOSUREField of the Disclosure[0002]The present disclosure relates to cutting, welding, and heating devices and, more particularly, to cutting torches with flashback arrestors.Discussion of Related Art[0003]Oxygen-fuel cutting, welding, or heating devices discharge fuel gas and oxygen from a nozzle for cutting, welding, or heating purposes. A typical torch includes a control body for connecting to separate fuel gas and oxygen supplies, tubes for supplying the oxygen and fuel gas from the control body to a head, and a cutting tip mounted to the head. The cutting tip receives the fuel gas and oxygen from the head and discharges these gases from its nozzle. More specifically, the head includes an interior surface extending around and defining a hea...

AI Technical Summary

Benefits of technology

This patent describes a torch body that includes a passageway and a cartridge assembly. The cartridge assembly includes a pressure-sensitive device and a thermal shut-off device that can change from a first configuration to a second configuration in response to pressure or temperature changes in the torch body. In the second configuration, the device restricts the flow of gas through the passageway. There is also a bushing and a check valve positioned along the passageway, which can work with either the pressure-sensitive device or the thermal shut-off device. The technical effect of this patent is that it provides a way for monitoring and controlling the flow of gas in a torch body, which can help improve the performance and efficiency of welding or cutting processes.

Problems solved by technology

Flashback may be caused by mixed gases (e.g., fuel / oxygen) that are allowed to develop within the welding hose due operator error, improper gas pressure, and / or defective equipment.

More specifically, in some cases, improper procedure / operation can result in reverse flow of oxygen into the fuel hose or reverse flow of fuel into the oxygen hose leading to mixed gas (e.g., flammable gas) within either hose.

Due to the rapid and explosive nature of flashback, it poses a major safety hazard to the operator of the gas torch and can damage the gas torch and associated equipment.

Although this stops the flashback from traveling upstream from the components that supply the gas to the torch, it disadvantageously does not eliminate the effects of flashback within the torch itself.

As a result, the torch can still be damaged or the operator can be injured by flashback within the torch.

However, this packing material may become damaged, such as by becoming clogged with carbon deposits resulting from flashback.

Disadvantageously, the removal and replacement of packing material in cutting torches is labor intensive.

Additionally, and of significant safety importance, if the packing material is not properly packed it may not perform its intended function, which can result in damage to the torch or injury to its operator.

Check valves, however, are mechanical devices that may become unreliable when contaminated with dirt or debris, which can cause the check valve to leak.

Moreover, the check valves cannot prevent flashback flame from propagating upstream once flashback occurs.

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