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81-398: Granata is an Italian word for “grenade”. The Russian word Granata can mean either Grenade or Pomegranate . Grenade Grenades work by dispersing fragments (fragmentation grenades), shockwaves ( high-explosive , anti-tank and stun grenades ), chemical aerosols ( smoke , gas and chemical grenades ) or fire ( incendiary grenades ). Their outer casings, generally made of

162-751: A cupola , but in modern applications, it is more often melted in electric induction furnaces or electric arc furnaces. After melting is complete, the molten cast iron is poured into a holding furnace or ladle. Cast iron's properties are changed by adding various alloying elements, or alloyants . Next to carbon , silicon is the most important alloyant because it forces carbon out of solution. A low percentage of silicon allows carbon to remain in solution, forming iron carbide and producing white cast iron. A high percentage of silicon forces carbon out of solution, forming graphite and producing grey cast iron. Other alloying agents, manganese , chromium , molybdenum , titanium , and vanadium counteract silicon, and promote

243-464: A 10-tonne impeller) to be sand cast, as the chromium reduces cooling rate required to produce carbides through the greater thicknesses of material. Chromium also produces carbides with impressive abrasion resistance. These high-chromium alloys attribute their superior hardness to the presence of chromium carbides. The main form of these carbides are the eutectic or primary M 7 C 3 carbides, where "M" represents iron or chromium and can vary depending on

324-526: A Byzantine invention of the previous century, could not only be thrown by flamethrowers at the enemy but also in stone and ceramic jars. Later, glass containers were employed. In Song China (960–1279), weapons known as ' thunder crash bombs ' ( 震天雷 ) were created when soldiers packed gunpowder into ceramic or metal containers fitted with fuses. A 1044 military book, Wujing Zongyao ( Compilation of Military Classics ), described various gunpowder recipes in which one can find, according to Joseph Needham ,

405-561: A five-second fuze with a match-tip that was ignited by striking on a ring on the soldier's hand. William Mills , a hand grenade designer from Sunderland , patented, developed and manufactured the " Mills bomb " at the Mills Munition Factory in Birmingham , England in 1915, designating it the No.5. It was described as the first "safe grenade". They were explosive-filled steel canisters with

486-529: A grenade which could operate in either fragmentation or blast mode (selected at any time before throwing), the electronically fuzed enhanced tactical multi-purpose ( ET-MP ) hand grenade. During the Great War, handgrenades were frequently used by troops, lacking other means to defend against enemy tanks threatening to over-run the position, to various success. The Interwar period saw some limited development of grenades specifically intended to defeat armour, but it

567-404: A hand grenade, the objective is to have the grenade explode so that the target is within its effective radius while keeping the thrower out of the same. For this reason, several systems has been used to trigger the explosion. Impact was the first used, with fragile containers of Greek fire that ruptured when landing. Later impact fuzes contained some kind of sensitive explosive to either initiate

648-514: A hard synthetic material or steel, are designed to rupture and fragment on detonation, sending out numerous fragments ( shards and splinters ) as fast-flying projectiles. In modern grenades, a pre-formed fragmentation matrix inside the grenade is commonly used, which may be spherical, cuboid, wire or notched wire. Most anti-personnel (AP) grenades are designed to detonate either after a time delay or on impact. Grenades are often spherical, cylindrical, ovoid or truncated ovoid in shape, and of

729-505: A loud popping noise and a puff of smoke on detonation. The grenade body can be reused. Another type is the throwing practice grenade which is completely inert and often cast in one piece. It is used to give soldiers a feel for the weight and shape of real grenades and for practicing precision throwing. Examples of practice grenades include the K417 Biodegradable Practice Hand Grenade by CNOTech Korea. When using

810-563: A rule of mixtures. In any case, they offer hardness at the expense of toughness . Since carbide makes up a large fraction of the material, white cast iron could reasonably be classified as a cermet . White iron is too brittle for use in many structural components, but with good hardness and abrasion resistance and relatively low cost, it finds use in such applications as the wear surfaces ( impeller and volute ) of slurry pumps , shell liners and lifter bars in ball mills and autogenous grinding mills , balls and rings in coal pulverisers . It

891-459: A size that fits the hand of an average-sized adult. Some grenades are mounted at the end of a handle and known as " stick grenades ". The stick design provides leverage for throwing longer distances, but at the cost of additional weight and length, and has been considered obsolete by western countries since the Second World War and Cold War periods. A friction igniter inside the handle or on

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972-424: A spongy steel without the stress concentration effects that flakes of graphite would produce. The carbon percentage present is 3-4% and percentage of silicon is 1.8-2.8%.Tiny amounts of 0.02 to 0.1% magnesium , and only 0.02 to 0.04% cerium added to these alloys slow the growth of graphite precipitates by bonding to the edges of the graphite planes. Along with careful control of other elements and timing, this allows

1053-446: A spring-loaded striker hit the cap after the grenade is released like the Mills bomb with the latter being predominant since WWII. There is also an alternative technique of throwing, where the grenade is not thrown immediately after the fuze is ignited, which allows the fuze to burn partially and decrease the time to detonation after throwing; this is referred to as "cooking". A shorter delay

1134-483: A time delay or on impact. Modern fragmentation grenades, such as the United States M67 grenade , have a wounding radius of 15 m (49 ft) – half that of older style grenades, which can still be encountered – and can be thrown about 40 m (130 ft). Fragments may travel more than 200 m (660 ft). These grenades are usually classed as offensive weapons because the effective casualty radius

1215-402: A triggering pin and a distinctive deeply notched surface. This segmentation is often erroneously thought to aid fragmentation , though Mills' own notes show the external grooves were purely to aid the soldier to grip the weapon. Improved fragmentation designs were later made with the notches on the inside, but at that time they would have been too expensive to produce. The external segmentation of

1296-417: A wide range of applications and are used in pipes , machines and automotive industry parts, such as cylinder heads , cylinder blocks and gearbox cases. Some alloys are resistant to damage by oxidation . In general, cast iron is notoriously difficult to weld . The earliest cast-iron artefacts date to the 5th century BC, and were discovered by archaeologists in what is now Jiangsu , China. Cast iron

1377-399: A year after it was opened. The Dee bridge disaster was caused by excessive loading at the centre of the beam by a passing train, and many similar bridges had to be demolished and rebuilt, often in wrought iron . The bridge had been badly designed, being trussed with wrought iron straps, which were wrongly thought to reinforce the structure. The centres of the beams were put into bending, with

1458-438: Is added in the ladle or in the furnace, on the order of 0.5–2.5%, to decrease chill, refine graphite, and increase fluidity. Molybdenum is added on the order of 0.3–1% to increase chill and refine the graphite and pearlite structure; it is often added in conjunction with nickel, copper, and chromium to form high strength irons. Titanium is added as a degasser and deoxidizer, but it also increases fluidity. Vanadium at 0.15–0.5%

1539-439: Is added to cast iron to stabilize cementite, increase hardness, and increase resistance to wear and heat. Zirconium at 0.1–0.3% helps to form graphite, deoxidize, and increase fluidity. In malleable iron melts, bismuth is added at 0.002–0.01% to increase how much silicon can be added. In white iron, boron is added to aid in the production of malleable iron; it also reduces the coarsening effect of bismuth. Grey cast iron

1620-420: Is characterised by its graphitic microstructure, which causes fractures of the material to have a grey appearance. It is the most commonly used cast iron and the most widely used cast material based on weight. Most cast irons have a chemical composition of 2.5–4.0% carbon, 1–3% silicon, and the remainder iron. Grey cast iron has less tensile strength and shock resistance than steel, but its compressive strength

1701-481: Is comparable to low- and medium-carbon steel. These mechanical properties are controlled by the size and shape of the graphite flakes present in the microstructure and can be characterised according to the guidelines given by the ASTM . White cast iron displays white fractured surfaces due to the presence of an iron carbide precipitate called cementite. With a lower silicon content (graphitizing agent) and faster cooling rate,

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1782-453: Is difficult to cool thick castings fast enough to solidify the melt as white cast iron all the way through. However, rapid cooling can be used to solidify a shell of white cast iron, after which the remainder cools more slowly to form a core of grey cast iron. The resulting casting, called a chilled casting , has the benefits of a hard surface with a somewhat tougher interior. High-chromium white iron alloys allow massive castings (for example,

1863-595: Is known as the Iron Bridge in Shropshire , England. Cast iron was also used in the construction of buildings . Cast iron is made from pig iron , which is the product of melting iron ore in a blast furnace . Cast iron can be made directly from the molten pig iron or by re-melting pig iron, often along with substantial quantities of iron, steel, limestone, carbon (coke) and taking various steps to remove undesirable contaminants. Phosphorus and sulfur may be burnt out of

1944-533: Is much less than the distance it can be thrown, and its explosive power works better within more confined spaces such as fortifications or buildings , where entrenched defenders often occupy. The concussion effect, rather than any expelled fragments, is the effective killer. In the case of the US Mk3A2 , the casualty radius is published as 2 m (6 ft 7 in) in open areas, but fragments and bits of fuze may be projected as far as 200 m (660 ft) from

2025-433: Is one of the most common alloying elements, because it refines the pearlite and graphite structures, improves toughness, and evens out hardness differences between section thicknesses. Chromium is added in small amounts to reduce free graphite, produce chill, and because it is a powerful carbide stabilizer; nickel is often added in conjunction. A small amount of tin can be added as a substitute for 0.5% chromium. Copper

2106-545: Is the predominant system today, developed from the match-fuzes that were hand-lit in the early grenades. From there, two sub-groups were developed: friction-ignitors where a cord is pulled or a cap is twisted to ignite the delay-fuze like on the German Stielhandgranate; the other being strike- or percussion-ignitors where the user either hit the cap before the throw like on the Japanese Type 10 grenade , or have

2187-529: Is useful to reduce the ability of the enemy to take cover, throw or kick the grenade away and can also be used to allow a fragmentation grenade to explode into the air over defensive positions. Concerned with a number of serious incidents and accidents involving hand grenades, Ian Kinley at the Swedish Försvarets materielverk identified the two main issues as the time-fuze's burntime variation with temperature (slows down in cold and speeds up in heat) and

2268-755: Is very hard, but brittle, as it allows cracks to pass straight through; grey cast iron has graphite flakes which deflect a passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite "nodules" which stop the crack from further progressing. Carbon (C), ranging from 1.8 to 4 wt%, and silicon (Si), 1–3 wt%, are the main alloying elements of cast iron. Iron alloys with lower carbon content are known as steel . Cast iron tends to be brittle , except for malleable cast irons . With its relatively low melting point, good fluidity, castability , excellent machinability , resistance to deformation and wear resistance , cast irons have become an engineering material with

2349-682: The Chirk Aqueduct and the Pontcysyllte Aqueduct , both of which remain in use following the recent restorations. The best way of using cast iron for bridge construction was by using arches , so that all the material is in compression. Cast iron, again like masonry, is very strong in compression. Wrought iron, like most other kinds of iron and indeed like most metals in general, is strong in tension, and also tough – resistant to fracturing. The relationship between wrought iron and cast iron, for structural purposes, may be thought of as analogous to

2430-516: The Congo region of the Central African forest, blacksmiths invented sophisticated furnaces capable of high temperatures over 1000 years ago. There are countless examples of welding, soldering, and cast iron created in crucibles and poured into molds. These techniques were employed for the use of composite tools and weapons with cast iron or steel blades and soft, flexible wrought iron interiors. Iron wire

2511-644: The Governor of Jamaica in 1721. Improvised grenades were increasingly used from the mid-19th century, the confines of trenches enhancing the effect of small explosive devices. In a letter to his sister, Colonel Hugh Robert Hibbert described an improvised grenade that was employed by British troops during the Crimean War (1854–1856): We have a new invention to annoy our friends in their pits. It consists in filling empty soda water bottles full of powder, old twisted nails and any other sharp or cutting thing we can find at

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2592-671: The Hales rifle grenade , developed a modern hand grenade in 1906 but was unsuccessful in persuading the British Army to adopt the weapon until 1913. Hale's chief competitor was Nils Waltersen Aasen , who invented his design in 1906 in Norway, receiving a patent for it in England. Aasen began his experiments with developing a grenade while serving as a sergeant in the Oscarsborg Fortress . Aasen formed

2673-511: The Home Guard as an anti-tank weapon. It was produced in vast numbers; by August 1941 well over 6,000,000 had been manufactured. Sting grenades, also known as stingball or sting ball grenades, are stun grenades based on the design of the fragmentation grenade. Instead of using a metal casing to produce fragmentation, they are made from hard rubber and are filled with around 100 rubber or plastic balls. On detonation, these balls, and fragments from

2754-603: The Iraqi insurgency in the early 2000s against lightly armoured mine-resistant ambush protected (MRAP) vehicles, designed for protection only against improvised explosive devices , as well as drone ordnance in Ukraine 2022–2024. During World War II the United Kingdom used incendiary grenades based on white phosphorus . One model, the No. 76 special incendiary grenade , was mainly issued to

2835-609: The Jacobites in the battles of Killiecrankie and Glen Shiel . These grenades were not very effective owing both to the unreliability of their fuse, as well inconsistent times to detonation, and as a result, saw little use. Grenades were also used during the Golden Age of Piracy , especially during boarding actions; pirate Captain Thompson used "vast numbers of powder flasks, grenade shells, and stinkpots" to defeat two pirate-hunters sent by

2916-531: The Warring States period . This is based on an analysis of the artifact's microstructures. Because cast iron is comparatively brittle, it is not suitable for purposes where a sharp edge or flexibility is required. It is strong under compression, but not under tension. Cast iron was invented in China in the 5th century BC and poured into molds to make ploughshares and pots as well as weapons and pagodas. Although steel

2997-449: The springs , the striker spring in particular, coming pre-tensioned from the factory by mechanism designs that had not changed much since the 1930s. In 2019, a new mechanism, fully interchangeable with the old ones, was adopted into service. The main difference, apart from a fully environmentally stable delay, is that the springs now are twist-tensioned by the thrower after the transport safety (pin and ring) has been removed, thus eliminating

3078-403: The surface tension to form the graphite into spheroidal particles rather than flakes. Due to their lower aspect ratio , the spheroids are relatively short and far from one another, and have a lower cross section vis-a-vis a propagating crack or phonon . They also have blunt boundaries, as opposed to flakes, which alleviates the stress concentration problems found in grey cast iron. In general,

3159-634: The 13th century and other travellers subsequently noted an iron industry in the Alburz Mountains to the south of the Caspian Sea . This is close to the silk route , thus the use of cast-iron technology being derived from China is conceivable. Upon its introduction to the West in the 15th century it was used for cannon and shot . Henry VIII (reigned 1509–1547) initiated the casting of cannon in England. Soon, English iron workers using blast furnaces developed

3240-528: The 1720s and 1730s by a small number of other coke -fired blast furnaces. Application of the steam engine to power blast bellows (indirectly by pumping water to a waterwheel) in Britain, beginning in 1743 and increasing in the 1750s, was a key factor in increasing the production of cast iron, which surged in the following decades. In addition to overcoming the limitation on water power, the steam-pumped-water powered blast gave higher furnace temperatures which allowed

3321-731: The Aasenske Granatkompani in Denmark, which before the First World War produced and exported hand grenades in large numbers across Europe. He had success in marketing his weapon to the French and was appointed as a Knight of the French Legion of Honour in 1916 for the invention. The Royal Laboratory developed the No. 1 grenade in 1908. It contained explosive material with an iron fragmentation band, with an impact fuze , detonating when

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3402-653: The Paraguayan troops used hand grenades in their attempt to board Brazilian ironclad warships with canoes. Hand grenades were used on naval engagements during the War of the Pacific . During the Siege of Mafeking in the Second Boer War , the defenders used fishing rods and a mechanical spring device to throw improvised grenades. Improvised hand grenades were used to great effect by

3483-668: The Russian defenders of Port Arthur (now Lüshun Port ) during the Russo-Japanese War . Around the turn of the 20th century, the ineffectiveness of the available types of hand grenades, coupled with their levels of danger to the user and difficulty of operation, meant that they were regarded as increasingly obsolete pieces of military equipment. In 1902, the British War Office announced that hand grenades were obsolete and had no place in modern warfare. But within two years, following

3564-488: The alloy's composition. The eutectic carbides form as bundles of hollow hexagonal rods and grow perpendicular to the hexagonal basal plane. The hardness of these carbides are within the range of 1500-1800HV. Malleable iron starts as a white iron casting that is then heat treated for a day or two at about 950 °C (1,740 °F) and then cooled over a day or two. As a result, the carbon in iron carbide transforms into graphite and ferrite plus carbon. The slow process allows

3645-429: The benefit of what is called precipitation hardening (as in some steels, where much smaller cementite precipitates might inhibit [plastic deformation] by impeding the movement of dislocations through the pure iron ferrite matrix). Rather, they increase the bulk hardness of the cast iron simply by virtue of their own very high hardness and their substantial volume fraction, such that the bulk hardness can be approximated by

3726-520: The blast furnaces at Coalbrookdale. Other inventions followed, including one patented by Thomas Paine . Cast-iron bridges became commonplace as the Industrial Revolution gathered pace. Thomas Telford adopted the material for his bridge upstream at Buildwas , and then for Longdon-on-Tern Aqueduct , a canal trough aqueduct at Longdon-on-Tern on the Shrewsbury Canal . It was followed by

3807-536: The blast.. Fragmentation grenades are common in armies. They are weapons that are designed to disperse fragments on detonation, aimed to damage targets within the lethal and injury radii. The body is generally made of a hard synthetic material or steel, which will provide some fragmentation as shards and splinters, though in modern grenades a pre-formed fragmentation matrix is often used. The pre-formed fragmentation may be spherical, cuboid, wire or notched wire. Most explosive grenades are designed to detonate either after

3888-531: The bolt holes were also cast and not drilled. Thus, because of casting's draft angle, the tension from the tie bars was placed on the hole's edge rather than being spread over the length of the hole. The replacement bridge was built in wrought iron and steel. Further bridge collapses occurred, however, culminating in the Norwood Junction rail accident of 1891. Thousands of cast-iron rail underbridges were eventually replaced by steel equivalents by 1900 owing to

3969-522: The carbon in white cast iron precipitates out of the melt as the metastable phase cementite , Fe 3 C, rather than graphite. The cementite which precipitates from the melt forms as relatively large particles. As the iron carbide precipitates out, it withdraws carbon from the original melt, moving the mixture toward one that is closer to eutectic , and the remaining phase is the lower iron-carbon austenite (which on cooling might transform to martensite ). These eutectic carbides are much too large to provide

4050-439: The carbon to separate as spheroidal particles as the material solidifies. The properties are similar to malleable iron, but parts can be cast with larger sections. Cast iron and wrought iron can be produced unintentionally when smelting copper using iron ore as a flux. The earliest cast-iron artifacts date to the 5th century BC, and were discovered by archaeologists in what is now modern Luhe County , Jiangsu in China during

4131-621: The cotton, hemp , or wool being spun. As a result, textile mills had an alarming propensity to burn down. The solution was to build them completely of non-combustible materials, and it was found convenient to provide the building with an iron frame, largely of cast iron, replacing flammable wood. The first such building was at Ditherington in Shrewsbury , Shropshire. Many other warehouses were built using cast-iron columns and beams, although faulty designs, flawed beams or overloading sometimes caused building collapses and structural failures. During

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4212-524: The detonation point. Concussion grenades have also been used as depth charges (underwater explosives) around boats and underwater targets; some like the US Mk 40 concussion grenade are designed for use against enemy divers and frogmen . Underwater explosions kill or otherwise incapacitate the target by creating a lethal shock wave underwater. The US Army Armament Research, Development and Engineering Center (ARDEC) announced in 2016 that they were developing

4293-582: The development of steel-framed skyscrapers. Cast iron was also used sometimes for decorative facades, especially in the United States, and the Soho district of New York has numerous examples. It was also used occasionally for complete prefabricated buildings, such as the historic Iron Building in Watervliet, New York . Another important use was in textile mills . The air in the mills contained flammable fibres from

4374-520: The effects of sulfur, manganese is added, because the two form into manganese sulfide instead of iron sulfide. The manganese sulfide is lighter than the melt, so it tends to float out of the melt and into the slag . The amount of manganese required to neutralize sulfur is 1.7 × sulfur content + 0.3%. If more than this amount of manganese is added, then manganese carbide forms, which increases hardness and chilling , except in grey iron, where up to 1% of manganese increases strength and density. Nickel

4455-461: The enemy camp, the whole place will be set ablaze... Grenade-like devices were also known in ancient India. In a 12th-century Persian historiography, the Mojmal al-Tawarikh , a terracotta elephant filled with explosives set with a fuse was placed hidden in the van and exploded as the invading army approached. A type of grenade called the 'flying impact thunder crash bomb' (飛擊震天雷) was developed in

4536-721: The late 16th century and first used in September 1, 1592 by the Joseon Dynasty during the Japanese invasions of Korea . The grenade was 20 cm in diameter, weighed 10 kg, and had a cast iron shell. It contained iron pellets, and an adjustable fuse. The grenade was used with a dedicated grenade launcher called a 'wangu' (碗口). It was used in both the besieging and defense of fortifications, to great effect. The first cast-iron bombshells and grenades appeared in Europe in 1467, where their initial role

4617-526: The lower edge in tension, where cast iron, like masonry , is very weak. Nevertheless, cast iron continued to be used in inappropriate structural ways, until the Tay Rail Bridge disaster of 1879 cast serious doubt on the use of the material. Crucial lugs for holding tie bars and struts in the Tay Bridge had been cast integral with the columns, and they failed in the early stages of the accident. In addition,

4698-506: The main charge directly, or set off a primer charge that in turn detonates the main charge. This turned out to present significant drawbacks; either the primer is so sensitive that unintended and premature ignition happens, while a more stable substance often fails to set off the grenade when landing in softer ground, not seldom even allowing the targeted troops to hurl the grenade back. Thus, the only significant use of impact fuzes since WWI has been in anti-tank grenades. Fuze-delayed grenades

4779-768: The mid-17th century, infantry known as " grenadiers " began to emerge in the armies of Europe, who specialized in shock and close quarters combat, mostly with the usage of grenades and fierce melee combat. In 1643, it is possible that grenados were thrown amongst the Welsh at Holt Bridge during the English Civil War . The word grenade was also used during the events surrounding the Glorious Revolution in 1688, where cricket ball-sized (8.81 to 9 in (224 to 229 mm) in circumference) iron spheres packed with gunpowder and fitted with slow-burning wicks were first used against

4860-406: The molten iron, but this also burns out the carbon, which must be replaced. Depending on the application, carbon and silicon content are adjusted to the desired levels, which may be anywhere from 2–3.5% and 1–3%, respectively. If desired, other elements are then added to the melt before the final form is produced by casting . Cast iron is sometimes melted in a special type of blast furnace known as

4941-482: The original Mills bomb was retained, as it provided a positive grip surface. This basic "pin-and-pineapple" design is still used in some modern grenades. After the Second World War , the general design of hand grenades has been fundamentally unchanged, with pin-and-lever being the predominant igniter system with the major powers, though incremental and evolutionary improvements continuously were made. In 2012, Spränghandgranat 07 (shgr 07, "Blast hand-grenade 07")

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5022-485: The possibility of unintentional arming of the hand grenade. Modern manufacturers of hand grenades include: Cast-iron Cast iron is a class of iron – carbon alloys with a carbon content of more than 2% and silicon content around 1–3%. Its usefulness derives from its relatively low melting temperature. The alloying elements determine the form in which its carbon appears: white cast iron has its carbon combined into an iron carbide named cementite , which

5103-418: The properties of malleable cast iron are more like those of mild steel . There is a limit to how large a part can be cast in malleable iron, as it is made from white cast iron. Developed in 1948, nodular or ductile cast iron has its graphite in the form of very tiny nodules with the graphite in the form of concentric layers forming the nodules. As a result, the properties of ductile cast iron are that of

5184-419: The prototype of the modern hand grenade. The shells ( pào ) are made of cast iron, as large as a bowl and shaped like a ball. Inside they contain half a pound of 'divine fire' ( shén huǒ , gunpowder). They are sent flying towards the enemy camp from an eruptor ( mu pào ), and when they get there a sound like a thunder-clap is heard, and flashes of light appear. If ten of these shells are fired successfully into

5265-729: The relationship between wood and stone. Cast-iron beam bridges were used widely by the early railways, such as the Water Street Bridge in 1830 at the Manchester terminus of the Liverpool and Manchester Railway , but problems with its use became all too apparent when a new bridge carrying the Chester and Holyhead Railway across the River Dee in Chester collapsed killing five people in May 1847, less than

5346-475: The retention of carbon and the formation of those carbides. Nickel and copper increase strength and machinability, but do not change the amount of graphite formed. Carbon as graphite produces a softer iron, reduces shrinkage, lowers strength, and decreases density. Sulfur , largely a contaminant when present, forms iron sulfide , which prevents the formation of graphite and increases hardness . Sulfur makes molten cast iron viscous, which causes defects. To counter

5427-451: The rubber casing explode outward in all directions as reduced lethality projectiles, which may ricochet. It is intended that people struck by the projectiles will receive a series of fast, painful stings, without serious injury. Some types have an additional payload of CS gas . Sting grenades do not reliably incapacitate people, so they can be dangerous to use against armed subjects. They sometimes cause serious physical injury, especially

5508-467: The rubber fragments from the casing. People have lost eyes and hands to sting grenades. Sting grenades are sometimes called "stinger grenades", which is a genericized trademark as "Stinger" is trademarked by Defense Technology for its line of sting grenades. Chemical and gas grenades burn or release a gas, and do not explode. Practice or simulation grenades are similar in handling and function to other hand grenades, except that they only produce

5589-600: The success of improvised grenades in the trench warfare conditions of the Russo-Japanese War, and reports from General Sir Aylmer Haldane , a British observer of the conflict, a reassessment was quickly made and the Board of Ordnance was instructed to develop a practical hand grenade. Various models using a percussion fuze were built, but this type of fuze suffered from various practical problems, and they were not commissioned in large numbers. Marten Hale, known for patenting

5670-501: The technique of producing cast-iron cannons, which, while heavier than the prevailing bronze cannons, were much cheaper and enabled England to arm her navy better. Cast-iron pots were made at many English blast furnaces at the time. In 1707, Abraham Darby patented a new method of making pots (and kettles) thinner and hence cheaper than those made by traditional methods. This meant that his Coalbrookdale furnaces became dominant as suppliers of pots, an activity in which they were joined in

5751-464: The time, sticking a bit of tow in for a fuse then lighting it and throwing it quickly into our neighbors' pit where it bursts, to their great annoyance. You may imagine their rage at seeing a soda water bottle come tumbling into a hole full of men with a little fuse burning away as proud as a real shell exploding and burying itself into soft parts of the flesh. In March 1868 during the Paraguayan War ,

5832-580: The top of the grenade head was used to initiate the fuse. The word grenade is likely derived from the French word spelled exactly the same, meaning pomegranate , as the bomb is reminiscent of the many-seeded fruit in size and shape. Its first use in English dates from the 1590s. Rudimentary incendiary grenades appeared in the Eastern Roman (Byzantine) Empire , not long after the reign of Leo III (717–741). Byzantine soldiers learned that Greek fire ,

5913-602: The top of the grenade hit the ground. A long cane handle (approximately 16 inches or 40 cm) allowed the user to throw the grenade farther than the blast of the explosion. It suffered from the handicap that the percussion fuse was armed before throwing, which meant that if the user was in a trench or other confined space, he was apt to detonate it and kill himself when he drew back his arm to throw it. Early in World War I , combatant nations only had small grenades, similar to Hales' and Aasen's design. The Italian Besozzi grenade had

5994-556: The use of higher lime ratios, enabling the conversion from charcoal (supplies of wood for which were inadequate) to coke. The ironmasters of the Weald continued producing cast irons until the 1760s, and armament was one of the main uses of irons after the Restoration . The use of cast iron for structural purposes began in the late 1770s, when Abraham Darby III built The Iron Bridge , although short beams had already been used, such as in

6075-518: The widespread concern about cast iron under bridges on the rail network in Britain. Cast-iron columns , pioneered in mill buildings, enabled architects to build multi-storey buildings without the enormously thick walls required for masonry buildings of any height. They also opened up floor spaces in factories, and sight lines in churches and auditoriums. By the mid 19th century, cast iron columns were common in warehouse and industrial buildings, combined with wrought or cast iron beams, eventually leading to

6156-457: Was also produced. Numerous testimonies were made by early European missionaries of the Luba people pouring cast iron into molds to make hoes. These technological innovations were accomplished without the invention of the blast furnace which was the prerequisite for the deployment of such innovations in Europe and Asia. The technology of cast iron was transferred to the West from China. Al-Qazvini in

6237-480: Was announced as the first major innovation in the area of handgrenades since the Great War . Developed by Ian Kinley at Försvarets Materielverk (FMV), shgr 07 is a self-righting, jumping hand grenade containing some 1900 balls that covers a cone 10 metres in diameter with the centre about 2 metres in height. This minimize the dangers outside the lethal zone as there is little to no random scattering of fragments from

6318-410: Was more desirable, cast iron was cheaper and thus was more commonly used for implements in ancient China, while wrought iron or steel was used for weapons. The Chinese developed a method of annealing cast iron by keeping hot castings in an oxidizing atmosphere for a week or longer in order to burn off some carbon near the surface in order to keep the surface layer from being too brittle. Deep within

6399-481: Was not until the outbreak of WWII serious efforts were made. While there were infantry anti-tank weapons available, they were either not ubiquitous enough, ineffective or both. Anti-tank grenades were a suitable stopgap to ensure a rudimentary capability for every squad to be used for self-defence. Once rocket-propelled shaped charges became available in greater numbers, anti-tank hand grenades became almost obsolete. However, they were still used with limited success in

6480-511: Was used in ancient China to mass-produce weaponry for warfare, as well as agriculture and architecture. During the 15th century AD, cast iron became utilized for cannons and shot in Burgundy , France, and in England during the Reformation . The amounts of cast iron used for cannons required large-scale production. The first cast-iron bridge was built during the 1770s by Abraham Darby III , and

6561-474: Was with the besieging and defense of castles and fortifications. A hoard of several hundred ceramic hand grenades was discovered during construction in front of a bastion of the Bavarian city of Ingolstadt , Germany, dated to the 17th century. Many of the grenades retained their original black powder loads and igniters. The grenades were most likely intentionally dumped in the moat of the bastion prior to 1723. By

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