The carbonitriding of fasteners is of critical importance to their functionality and one of the most common case-hardening heat treatments. Studying how the process works in this application will shed a great deal of light on all carbonitriding processes. Let’s learn more.
Gas carbonitriding is a modified form of the carburizing process and is not a form of nitriding. In this process, both carbon (C) and nitrogen (N) are introduced into the surface of the steel by introducing ammonia (NH3) and a hydrocarbon enriching gas into the furnace atmosphere in order to add nitrogen to the carburized case as it is being produced.
L&L Special Furnace Co. Inc. delivered three bench-mounted box furnaces that will be used to test high-temperature aerospace fasteners. The fastener manufacturer now has five GS series furnaces at its facility in Pennsylvania. The furnaces have internal dimensions of 18 inches wide x 12 inches high x 24 inches deep. Included is a spring-assist vertical lift door that allows for effortless loading and unloading at high temperatures. The industrial control system includes a Eurotherm temperature controller, over-temperature protection and a recirculation fan for uniformity.
L&L Special Furnace Co. Inc. manufactured and supplied a high-uniformity, pit-style furnace used for annealing to a manufacturer of aerospace fasteners. The annealing process occurs when the parts are evenly heated to 1400°F (760°C) and held for a predetermined amount of time. Temperature uniformity is critical to this process, and both ambient and load temperature must maintain ±10°F throughout the cycle. The fastener parts are placed in baskets and loaded by an overhead crane into the furnace. There are guide bars to ensure that the load is centered and cannot damage the furnace liner. The program or recipe is entered into the program control, and the cycle is started. At the completion of the cycle, the parts are removed and are ready for inspection and shipment.
Most heat treaters are aware of many failure phenomena, perhaps the most well-known of which is hydrogen embrittlement (aka hydrogen-assisted cracking). But there are several other types, such as liquid-metal embrittlement, that we must understand as well. Let’s learn more.
SECO/WARWICK delivered an all-metal high-vacuum furnace with a work-chamber size of 1,200 mm x 1,200 mm x 1,200 mm to Hauck Heat Treatment Group’s recently expanded plant in Eindhoven, Netherlands. According to the companies, it is the largest furnace of its type currently in operation in the Benelux region. It is also the third furnace SECO/WARWICK has delivered to Hauck’s Eindhoven facility. In addition, SECO/WARWICK has established a strong cooperation with Hauck’s plant in Poland, where new vacuum furnaces are scheduled to be delivered.
OSR Inc., a manufacturer of automotive fasteners, plans to increase its manufacturing production in Columbus, Ind. The company, a joint venture between Japan’s Owari Precise Products Co. and Columbus-based Rightway Fasteners Inc., will invest $7 million to construct and equip a new 82,395-square-foot manufacturing facility. OSR plans to add up to 12 new positions and is hiring immediately for positions in heat treatment and IT. Production is scheduled to increase at the beginning of 2020.
AFC-Holcroft received an order from a Midwestern facility of a U.S.-based manufacturer of safety-critical fasteners and assembly solutions for a mesh-belt furnace. The new equipment will replace an older AFC-Holcroft installation. The furnace, which will be used in the production of metal fasteners, will integrate with existing companion equipment including a loading system, pre- and post-wash systems, oil quench and temper furnace.
Can-Eng Furnaces International Ltd. commissioned a continuous mesh-belt heat-treat system for the production of high-quality automotive fasteners in the Piedmont region of Italy. The high-volume fastener system features energy-efficient combustion and waste-heat recovery systems, atmosphere-controlled mesh-belt hardening system, oil quench, post-wash system, temper furnace, soluble oil system, bi-directional conveyor discharge and Can-Eng’s Level 2 SCADA system. The system was commissioned in the fourth quarter of 2018 and has exceeded the company’s performance expectations.
Can-Eng Furnaces International Ltd. has been contracted to design and commission a large-capacity fastener hardening system for a Tier 1 automotive supplier based in Detroit, Mich. The system closely integrates a computerized part-tracking and metering system, pre-washer, mesh-belt hardening furnace, oil-quench system, post-washer, temper furnace, soluble oil system, endothermic-gas generator and level 2 automation system. It is engineered to produce at a rated capacity of 6,000 pounds (2,700 kg) per hour.
United Process Controls (UPC) delivered an Atmosphere Engineering EndoFlex endothermic-gas generator to Jomarca, a fastener manufacturer in South America. The generator is intended for carburizing operations at the company’s Brazilian plant, which includes 10 large continuous rotary-retort furnaces that process over 2,200 tons of fasteners a month. The high-capacity generator was integrated into the plant’s existing gas-distribution system in the first quarter of 2018 and is supplying endothermic gas to all carburizing furnaces.
Check out the October 8, 2020 issue of Industrial Heating, featuring the "Improving Kiln ROI: Taking Back Lost Profits with a Bricking Machine", "Industrial Automation: Manufacturing, Heat Treating and Data Analytics", "Optimizing Burner Management and Combustion Control with Safety PLCs", and much more.