Forging makes it possible to obtain a metal part of the desired shape by deforming the metal by applying a significant force, cold or hot, by shock or by pressure using a hammer -pestle, a forging press or a forging machine. Forging is a very accident-prone industrial activity ...
Forging makes it possible to obtain a metal part of the desired shape by deforming the metal by applying a significant force, cold or hot, by shock or by pressure using a hammer -pestle, a forge press or an ark industrial forge machine.
Forging is a very accident-prone industrial activity: to the high risks of strong noise emissions, cuts and crushing of the hands, projections of metal dust and scale, fumes from the lubricants of the dies, are added the exposure to high temperatures and thermal burns and the requirements of handling and awkward postures.
The physical and chemical risks of forges can be controlled by the use of machines and equipment that comply with standards, with protective and signaling devices and physical and immaterial barriers, gas capture and dust as close as possible to their point of emission, effective ventilation, and compliance with essential safety requirements (fight against noise, hygiene of premises, etc.) and personal protection, with sustained attention during periods of setting up tools and starting production, or during machine maintenance and repair operations.
The main occupational hazards in industrial forges
Forging is a process of shaping malleable metals by hammering or pressing, most often by hot plastic deformation. Forged metal is stronger and more ductile than cast metal, and capable of large thermal variations and mechanical stresses.
There are several types of forging operations (hammering, stamping, forging, extrusion…). This is how the shaping of metal parts (from bars, blanks or pieces of metal) by applying powerful shocks or compressive forces is an operation carried out:
- Either hot, by a striking device (hammering) against a support (anvil) or by pressure between two blocks (stamping dies).
- Either cold, by very strong pressure exerted by a punch (extrusion) in a die.
In the automotive industry, forging is used to produce forged steel parts, engines (connecting rods, crankshafts, …), transmissions (shafts and crowns of differential, …) and suspensions, and s& #39;is made by means of induction heated billets placed on forging presses or by forging on drop hammers.
In the aircraft industry, high-strength components (wing spars, turbine discs and landing gear components) are forged and pounded from special steels, aluminum, titanium or nickel and steel alloys.
The hot forging temperatures are of the order of 1250°C for steel, 700°C for brass, 900°C for titanium and the heating of the metal before striking is carried out thanks to induction generators or oil- or gas-fired furnaces.
We use vertical or horizontal forging presses, screw or hydraulic, fully or partially automated, manual horizontal forging machines depending on the size of the series to be manufactured.
Drop hammers use a cylinder of steam or compressed air to lift the hammer.
Blacksmiths occupy several specialized positions: rammer, forging press operator, stamping operator, oven driver, lubricator, etc.: they work in difficult conditions specific to this heavy industry, in a very noisy and hot atmosphere. Blacksmithing uses ovens to heat the raw parts which expose them to high heat and infrared rays and blacksmiths use many chemicals, some of which are allergenic and carcinogenic, including the breakdown products of the combustion of lubricants. Thermal risks linked to hot metal, chemical risks linked to the products used and physical risks linked to handling, machinery, etc. make forging a very accident-prone activity.