OTT-JAKOBHelical springIt is an elastic device that stores and releases mechanical energy and is manufactured using a variety of materials, the most common of which is steel. The production of helical springs involves the use of simple winding mechanisms, such as mandrel, mandrel or cylinder, regardless of the shape, size or end use of the spring.

Whether cold-wound or hot-wound coil springs, they all start with long wires of different diameters. The type of process used to manufacture coil springs depends on whether the production run is small batch production, which is done on lathes, or large batch production, which is produced on automatic winders or computer numerical control (CNC) machines.

Helical spring material

Materials used to make coil springs include different forms of steel and alloys. The most common metal types include high and medium carbon steel, chromium-vanadium steel, chromium-silicon steel, various grades of stainless steel, copper and nickel. The choice of metal depends on the application in which helical springs are used. In all cases, the metal comes in the form of a wire. In some manufacturing instances, the metal is delivered in the form of metal rods that are heated and drawn into wires of the appropriate diameter.

Cold winding process

Heat treatment - Cold winding begins with heat treatment of the wire or efforts to reach its highest level of strength. The cold-wound process can only use wires with a diameter of 0.75 inches or 18 mm or less.

Mandrel - Mandrel is one of two methods used to produce coil springs. The process can be done using a lathe, winding machine or a hand crank machine. The guide mechanism is used to align the wire to the desired spacing, that is, the distance between the wires as it winds.

Hot winding

Wire - Wire used for hot coil winding can be thicker, varying in thickness from 3 inches or 75 mm to 6 inches or 150 mm. Wires for thermal winding are heated to 1700o F, which is why manufacturers can use larger diameter wires.

Mandrel - Heated metal is wound around the mandrel in the same process as cold winding, but with more care. A CNC machine controls the rotation and pitch of the spindle.

Cooling - The next step in the hot coil winding is to cool the wound coil as quickly as possible, a process called quenching. There are several different methods used to quench steel parts, one of the most commonly used is oil. The purpose of cooling is to harden the coil of steel and minimize the formation of thermal gradients and phase transition gradients that can cause cracking.

Extreme cooling alters the crystal structure of metal parts and freezes the changes, making the metal harder. When cooling begins, a layer of steam forms around the parts as the first stage of the process. The vapor layer is removed by heating a quenching agent, after which a convection stage further removes heat to cool the part.

Heat treatment

Whether the spring is hot or cold, it must be heat treated to reduce the stress on the metal and help it maintain its normal elasticity. The winding process creates stress in the material to prevent deformation such as cracking. The heat treatment process consists of placing the coil spring in an oven at a set temperature for a specified time to release the stress. Once heated, allow to cool slowly.

Stress relief temperature is between 350o F and 500o F. The process temperature varies with the material. The cooling can last one to two hours to avoid the tension associated with the temperature difference of the material. For larger springs, the complexity of the cooling process becomes even more critical.

Finished coil spring

The finishing of a coil spring depends on its design, which may vary according to its shape, coating, pitch setting, and how it is reinforced.

Grinding - Some springs require grinding to flatten their ends to match their design. The grinding process is done manually or automatically according to the manufacturing process. For manual grinding, the helical spring is held in place by a clamp and grinded using a grinding tool. Through automatic grinding, the spring is fixed in place and both ends are polished according to the machine programming.

The above content describes how the coil spring is made. OTT-JAKOB spring production process problems. In addition, Shenzhen Oudejie Technology specializes in the sale of new imported OTT-JAKOB spring, and promises to sell products are new imported, while providing our customers with quotation, selection, product information and other services.