Double hammer

Last updated

A double hammer is a forging implement used in metallurgy. It operates on puddle balls and blooms by hitting both sides at the same time. [1] Double hammers are made of two blocks attached to rollers which facilitate opposing movement along a set of rails. [2] Double hammers are normally operated by three people at a time: one holding the instrument in place and the other two moving the blocks back and forth. [3]

Related Research Articles

Metallurgy Domain of materials science that studies the physical and chemical behavior of metals

Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals; that is, the way in which science is applied to the production of metals, and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist.

Revolver Type of repeating handgun that has a cylinder holding the cartridges

A revolver is a repeating handgun that has at least one barrel and uses a revolving cylinder containing multiple chambers for firing. Before firing a round, cocking the hammer partially rotates the cylinder, indexing one of the cylinder chambers into alignment with the barrel, allowing the bullet to be fired through the bore. The hammer cocking can be achieved by either the user manually pulling the hammer back, via internal linkage relaying a rearward movement of the trigger, or both. By sequentially rotating through each chamber, the revolver allows the user to fire multiple times until having to reload the gun, unlike older single-shot firearms that had to be reloaded after each shot.

Action (firearms) Functional mechanism of breech-loading

In firearms terminology, an action is the functional mechanism of a breech-loading firearm that handles the ammunition cartridges, or the method by which that mechanism works. Actions are technically not present on muzzleloaders, as all those are single-shot firearms with a closed off breech with the powder and projectile manually loaded from the muzzle. Instead, the muzzleloader ignition mechanism is referred to as the lock.

Browning Hi-Power American-Belgian semi-automatic pistol

The Browning Hi-Power is a single-action, semi-automatic handgun available in the 9mm and .40 S&W calibers. It was based on a design by American firearms inventor John Browning, and completed by Dieudonné Saive at Fabrique Nationale (FN) of Herstal, Belgium. Browning died in 1926, several years before the design was finalized. FN Herstal initially named the design the "High Power", which alludes to the 13-round magazine capacity, almost twice that of other designs at the time, such as the Luger or Colt M1911.

Bellows Contraption for drawing and blowing air

A bellow or pair of bellows is a device constructed to furnish a strong blast of air. The simplest type consists of a flexible bag comprising a pair of rigid boards with handles joined by flexible leather sides enclosing an approximately airtight cavity which can be expanded and contracted by operating the handles, and fitted with a valve allowing air to fill the cavity when expanded, and with a tube through which the air is forced out in a stream when the cavity is compressed. It has many applications, in particular blowing on a fire to supply it with air.

Semi-automatic pistol Type of pistol

A semi-automatic pistol is a type of repeating single-chamber handgun (pistol) that automatically cycles its action to insert the subsequent cartridge into the chamber (self-loading), but requires manual actuation of the trigger to actually discharge the following shot. As a result, only one round of ammunition is fired each time the trigger is pulled, as the pistol's fire control group disconnects the trigger mechanism from the firing pin/striker until the trigger has been released and reset.

Copper extraction Process of extracting copper from the ground

Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper consists of a series of physical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.

SIG Sauer P220 Swiss-German semi-automatic pistol

The SIG Sauer P220 is a semi-automatic pistol. Designed in 1975 by the SIG Arms AG division of Schweizerische Industrie Gesellschaft, and produced by J. P. Sauer & Sohn, in Eckernförde; it is currently manufactured by both SIG Sauer companies: SIG Sauer GMBH, of Eckernförde, Germany; and SIG Sauer, Inc., of New Hampshire, United States.

Bloomery Type of furnace once used widely for smelting iron from its oxides

A bloomery is a type of metallurgical furnace once used widely for smelting iron from its oxides. The bloomery was the earliest form of smelter capable of smelting iron. Bloomeries produce a porous mass of iron and slag called a bloom. The mix of slag and iron in the bloom, termed sponge iron, is usually consolidated and further forged into wrought iron. Blast furnaces, which produce pig iron, have largely superseded bloomeries.

Trip hammer

A trip hammer, also known as a tilt hammer or helve hammer, is a massive powered hammer. Traditional uses of trip hammers include pounding, decorticating and polishing of grain in agriculture. In mining, trip hammers were used for crushing metal ores into small pieces, although a stamp mill was more usual for this. In finery forges they were used for drawing out blooms made from wrought iron into more workable bar iron. They were also used for fabricating various articles of wrought iron, latten, steel and other metals.

Rolling block Firearm action, subclass of breech loader

A rolling-block action is a form of firearm action where the sealing of the breech is done with a specially shaped breechblock able to rotate on a pin. The breechblock is shaped like a section of a circle. The breechblock is locked into place by the hammer, thus preventing the cartridge from moving backwards at the moment of firing. By cocking the hammer, the breechblock can be rotated freely to reload the weapon.

Trigger (firearms) Mechanism that activates a gun

A trigger is a mechanism that actuates the function of a ranged weapon such as a firearm, airgun, crossbow, or speargun. The word may also be used to describe a switch that initiates the operation of other non-shooting devices such as a trap, a power tool or a quick release. A small amount of energy applied to the trigger leads to the release of much more energy.

Hammerless

A hammerless firearm is a firearm that lacks an exposed hammer or hammer spur. Although it may not literally lack a hammer, it lacks a hammer that the user can pull directly. One of the disadvantages of an exposed hammer spur is the tendency to get caught on items such as clothing; covering the hammer by removing the spur reduces this tendency.

Break action

Break action is a type of firearm action in which the barrel or barrels are hinged much like a door and rotate perpendicularly to the bore axis to expose the breech and allow loading and unloading of cartridges. A separate operation may be required for the cocking of a hammer to fire the new round. There are many types of break-action firearms; break actions are universal in double-barrelled shotguns, double rifles and combination guns, and are also common in single shot rifles, pistols, and shotguns, and can also be found in flare guns, grenade launchers, air guns and some older revolver designs. They are also known as hinge-action, break-open, break-barrel, break-top, or, on old revolvers, top-break actions.

Handgun Short-barreled firearm designed to be held and used with one hand

A handgun is a short-barrelled firearm that can be held and used with one hand. The two most common handgun sub-types in use today are revolvers and semi-automatic pistols, although other handgun-types such as derringers and machine pistols also see infrequent usage.

FB P-83 Wanad Semi-automatic pistol

The P-83 Wanad is a single-action and double-action Polish semi-automatic pistol, chambered for the 9×18mm Makarov cartridge and designed by Ryszard Chełmicki and Marian Gryszkiewicz of the state research institute Ośrodek Badawczo-Rozwojowy in Radom. The P-83 succeeded the P-64 as the sidearm for the Polish Army and police. The P-83 is still in limited use by both the Polish police and the Polish military but it has been mostly replaced by Glock 19 pistols in Police service and partially by the indigenous WIST 94 pistol in the Polish military.

Axe Type of wedge tool

An axe is an implement that has been used for millennia to shape, split and cut wood, to harvest timber, as a weapon, and as a ceremonial or heraldic symbol. The axe has many forms and specialised uses but generally consists of an axe head with a handle, or helve.

Metallurgy in pre-Columbian America

Metallurgy in pre-Columbian America is the extraction, purification and alloying of metals and metal crafting by Indigenous peoples of the Americas prior to European contact in the late 15th century. Indigenous Americans have been using native metals from ancient times, with recent finds of gold artifacts in the Andean region dated to 2155–1936 BCE, and North American copper finds dated to approximately 5000 BCE. The metal would have been found in nature without need for smelting, and shaped into the desired form using hot and cold hammering without chemical alteration or alloying. To date "no one has found evidence that points to the use of melting, smelting and casting in prehistoric eastern North America." In South America the case is quite different. Indigenous South Americans had full metallurgy with smelting and various metals being purposely alloyed. Metallurgy in Mesoamerica and Western Mexico may have developed following contact with South America through Ecuadorian marine traders.

Metals and metal working had been known to the people of modern Italy since the Bronze Age. By 53 BC, Rome had expanded to control an immense expanse of the Mediterranean. This included Italy and its islands, Spain, Macedonia, Africa, Asia Minor, Syria and Greece; by the end of the Emperor Trajan's reign, the Roman Empire had grown further to encompass parts of Britain, Egypt, all of modern Germany west of the Rhine, Dacia, Noricum, Judea, Armenia, Illyria, and Thrace. As the empire grew, so did its need for metals.

Safety (firearms) Feature on firearms to prevent accidental discharge

In firearms, a safety or safety catch is a mechanism used to help prevent the accidental discharge of a firearm, helping to ensure safer handling.

References

  1. Robert Hunter (1883). The Encyclopædic Dictionary. Cassell, Petter, Galpin and Co. p. 171.
  2. Louis Emmanuel Gruner; Lenox Smith (1872). The Manufacture of Steel. D. Van Nostrand. p.  55. double hammer metallurgy.
  3. Eugene Benjamin Wilson (1905). A Manual of Mining (4 ed.). John Wiley & Sons. p.  628.