770130 - Hobart 3/16" x 25' Grade R Oxy-Acetylene Twin Welding Hose

Technical Overview of the Hobart 770130 Grade R Twin Hose

The Hobart 770130 is a premium-quality Grade R twin welding hose assembly designed specifically for oxy-acetylene welding, cutting, and heating applications. Engineered with a 3/16-inch inner diameter (ID), this hose strikes an optimal balance between gas flow capacity and operator ergonomics. While 1/4-inch hoses are common for heavy industrial runs, the 3/16-inch diameter of this unit significantly reduces the drag weight on the torch handle, allowing for finer manipulation and reduced wrist strain during precision work. The hose measures 25 feet in length, a standard dimension that suits the majority of workshop cylinder cart configurations and bench-top setups.

Constructed from durable rubber compounds, the hose features a siamese (twin-line) design where the oxygen and fuel lines are molded together to prevent tangling and maintain a tidy workspace. The exterior is color-coded according to industry safety standards: green for oxygen and red for fuel gas. It comes factory-assembled with standard "B" size brass fittings (9/16"-18 threads). The oxygen fitting utilizes right-hand threads, while the acetylene fitting utilizes left-hand threads (indicated by the notched nut), ensuring that lines cannot be cross-connected at the regulator or torch end, a critical safety feature.

Safety and Compatibility Warning: This hose is classified as Grade R. It is chemically formulated for use with Acetylene gas only. It must not be used with alternate fuel gases such as Propane, Propylene, Natural Gas, or MAPP gas. These oil-based fuel gases can attack the rubber lining of Grade R hoses, causing the material to rot, crack, or delaminate from the inside out, leading to potential leaks and fire hazards. For applications involving propane or other fuel gases, a Grade T hose is required. Users must verify their fuel gas type before installation to ensure compliance with safety protocols.

The hose is resistant to kinking and general abrasion found in metalworking environments. However, as with all Grade R hoses, it should be kept free from oil and grease contamination to preserve the integrity of the rubber cover. This assembly is an ideal replacement for worn or damaged hoses on Hobart, Miller, and other major brand oxy-acetylene outfits.