British ships, such as HMTS Monarch and HMTS Alert solved the problem by providing a trough for the repeater to bypass the sheave. A rope connected in parallel to the repeater went through the sheave which pulled the cable back in to the sheave after the repeater had passed. It was normally necessary for the ship to slow down while the repeater was being laid.K. R. Haigh, Cableships and Submarine Cables, pp.
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Vibration signatures are widely used for studying belt drive malfunctions. Some of the common malfunctions or faults include the effects of belt tension, speed, sheave eccentricity and misalignment conditions. The effect of sheave Eccentricity on vibration signatures of the belt drive is quite significant. Although, vibration magnitude is not necessarily increased by this it will create strong amplitude modulation.
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Deficiencies were noted and in the early 1950s combines were equipped with what John Deere called the "Variable Speed Drive". This was simply a variable width sheave controlled by spring and hydraulic pressures. This sheave was attached to the input shaft of the transmission. A standard 4 speed manual transmission was still used in this drive system.
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The model at the Telegraph Museum Porthcurno shows an original configuration in which a "V" sheave was in the center flanked by two flat sheaves.
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As a temporary measure, in 1982, R22 operators received a kit from Robinson that was installed in the cockpit and on the belt tension actuator, isolating the tensioning circuits and locking the clutch/drive system at take-off tension. The problem was ultimately solved by replacing the four individual v-belts with two dual v-belts. The upper, driven sheave is mounted on the main/tail rotor drive shaft incorporating flexible couplings, and is raised and lowered relative to the engine-mounted, driving sheave by means of a belt tension actuator. During shutdown, the actuator is used to lower the upper sheave to loosen the drive belts.
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Two sheave wheels, diameter with a diameter and a rim lie on a nearby rubble heap. Both have sections of rim missing and some buckled spokes.
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If the sheave is too close to the drum, the fleet angle will be greater than 1.25°; if it is too far away, the fleet angle will be less than 0.25°.
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The dome slit, which still operates, has an opening of and can be opened or closed by hand in seconds. The dome tower and equatorial room are original save a motor drive which replaced the old rope and sheave method of rotating the dome. As of September 2014, the motor drive is being serviced and the rope and sheave method is once again in use. In the center of the equatorial room is the 1896 refractor telescope.
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Photos of show the change in bow sheaves after a modernization. In that case the entire ship was essentially rebuilt. The Monarch (4) page at History of the Atlantic Cable & Undersea Communications has a painting of Monarch anchored off Sesimbra during 1969 operations showing the drastic change in the ship's bow after the 1968 modernization. After a 1968 modification Monarch had three bow sheaves, a flat surface sheave and two "V" sheaves, and one "V" stern sheave.
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The main sheet traveler is stainless, typically a slide-car riding a 5/8 track mounted amidships, with small fair leads and cleats mounted inside the gunwales near the deck. The original fair leads and cleats were cast aluminum. The main sheet block is a fiddle attached to the slide, and a dual sheave block on the boom with the upper. The sheet comes off the upper large sheave to a block/camcleat mounted to the deck swivel for 6:1 purchase.
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Eccentric sheave, with strap and eccentric rod fitted. In mechanical engineering, an eccentric is a circular disk (eccentric sheave) solidly fixed to a rotating axle with its centre offset from that of the axle (hence the word "eccentric", out of the centre). It is used most often in steam engines, and used to convert rotary into linear reciprocating motion to drive a sliding valve or pump ram. To do so, an eccentric usually has a groove at its circumference closely fitted a circular collar (eccentric strap).
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Graphic depiction of a single lineset and the parts of a counterweight system. (A) Hoisting cables, (B) Turnbuckles, (C) Purchase line, (D) Arbor rod, (E) Spreader plates, (F) Cut steel counterweight, (G) Rope stop/lock (brake)/Lock rail, (H) Locking safety ring, (I) Tension sheave (block). Not shown: head sheave, loft sheaves, and batten. Counterweight fly system at FirstOntario Concert Hall in Hamilton, Ontario Locking rail and arbors First introduced in Austria in 1888, counterweight rigging systems are the most common fly systems in performing arts facilities today.
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The drill line then enters the first sheave of the crown block and makes typically 6 to 12 passes between the crown block and traveling block pulleys for mechanical advantage. The line then exits the last sheave on the crown block and is fastened to a derrick leg on the other side of the rig floor. This section of drill line is called the "dead line." A modern drawworks consists of five main parts: the drum, the power source, the reduction gear, the brake, and the auxiliary brake.
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Drum hoists are mounted on concrete slabs within a hoistroom, the hoisting ropes run from the drum, up to the top of the headframe, over a sheave wheel and down where they connect to the conveyance (cage or skip).
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211–214, Adlard Coles, 1968 . American ships, for a time, tried using flexible repeaters which passed through the sheave. However, by the 1960s they were also using rigid repeaters similar to the British system."Two new British cable ships completed", New Scientist, No. 240, p.
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For startup, the engine is started with the belts loose, allowing the engine to run without spinning the rotor system. Immediately after engine start, the clutch switch located in the cockpit is closed by the pilot, powering the actuator to slowly raise the upper sheave to flight position, which tightens the belts. The actuator is thereafter controlled by pressure-sensing column springs, automatically maintaining proper belt tension during flight as the belts wear and stretch. The shaft on which the upper sheave is mounted drives both the main and tail rotors; the main gear box delivers power to the main rotor shaft through a set of splash- lubricated spiral bevel gears.
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Thomas John Dobbs, who had been guiding the bowk down a guide rope, managed to slowly lowered himself to within hailing distance of pit bottom, and was rescued with nothing more than cuts and bruises. Following an accident investigation by HM Inspectorate of Mines, it was found that the rope had corroded, where it had been in contact with the headframe sheave wheel. But as the rope was covered with a protective coating of tar, the corrosion had gone undetected. The sheave wheels on both the No.1 and No.2 shafts at Deep Navigation were unusual, in that they were constructed of different parts that had been riveted together, not a singular wheel that had been cast.
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The headframe is a "wood four-post type headframe with one sheave instead of two. . . and stands high. . . ." It is the only four post headframe of its type within the Tintic Mining District. The headframe is located just east of Dividend Road (formerly Utah State Route 159), about east of Eureka.
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The colliery in 1994. The sheave wheel is preserved as a memorial. Littleton Colliery was a deep coal mine situated two miles north of Cannock on the A34 in the village of Huntington. The colliery closed on 3 December 1993 and was the last working coal mine on the Cannock Chase Coalfield.
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Embedded within the story are Tolkien's versions of European legends: 'King Sheave', and 'The Death of St. Brendan', a three-page poem also titled 'Imram'. Sauron Defeated includes some further 40 pages of commentary and notes on The Notion Club Papers by Christopher Tolkien, and reproduces examples of the pages hand- written by Tolkien.
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This canal may receive a circlip an o-ring or a gasket. # A depression on the entire circumference of a cast or machined wheel, a pulley or sheave. This depression may receive a cable, a rope or a belt. # A longitudinal channel formed in a hot rolled rail profile such as a grooved rail.
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Storey, Jack, (4 December 1992). "Shipwreck artifact dispute simmers". Evening News, p. A1. Following a settlement agreement, a single sheave block, shaving mug, pocket watch, mallet, pickax, saucer, and pitcher from the Sagamore are now the property of the State of Michigan and are on loan for display in the Great Lakes Shipwreck Museum.
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The two carriages, can carry up to 20 passengers seated and 10 standing, and when fully loaded each can weigh up to 8 tonnes, or 16 tonnes in total, well within the capacity of the 128 tonne breaking strength. The sheave wheel, gear box and motor located in the machine room below the top station. May 2019.
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Sometimes it is not possible to achieve the optimum fleet angle. Where there is no space to rig a sheave the requisite distance from the drum, two additional spooling devices are available. One is a fleet angle compensator, which is driven automatically by the rope tension. The other is a level winder that is mechanically driven.
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340–341 The cable- handling gear, built by Thames Iron Works and designed by W. B. Esson,Wilkinson, p. 250 could also double as a paying-out machine for cable- laying work. In this mode the winch was taken out of gear and controlled with the brake. The cable sheave was mounted on a boom on the bow.
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They made the boy their king, crowning him with a garland of golden wheat. Tolkien's Sheave fathers seven sons from whence came the Danes, Goths, Swedes, Northmen, Franks, Frisians, Swordmen (for the Swordmen cf. 'Widsith', v. 62: "Mid Seaxum ic wæs ond Sycgum ond mid Sweordwerum"; "I've been among the [tribes named] Saxons (Daggers), Swords and Swordsmen".
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On the night of January 26, 1904, non-union replacement workers were coming off shift in the Independence Mine when the cage that they were riding in had a serious mishap. The cage was drawn into the sheave wheel at the top of the shaft. The cable that supported the cage was severed, and the cage fell.Jameson, p.
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The wire rope had parted approximately where it rested over the topmost sheave, when the davit was in its stowed position. The fore and aft davit’s fall wires had been replaced on 22 August 2010 and the next scheduled replacement was due in August 2014. In November 2017 she joined "Celestyal Cruises" and renamed simply as "Majesty".
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The hoist frames were mounted on top of each pylon. Sheave blocks, winches and snatch blocks were used to facilitate the lifting, and cables inside the pylons were stressed with jacks. Pressure grouting was performed to fill the voids between the wire and the high-density polyethylene (HDPE) tubes. A two tonne tower crane, fixed inside the pylons, lifted the cables into position.
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Forests without lianas grow 150% more fruit; trees with lianas have twice the probability of dying. The word liana does not refer to a taxonomic grouping, but rather a habit of plant growth – much like tree or shrub. It comes from standard French liane, itself from an Antilles French dialect word meaning to sheave. Lianas may be found in many different plant families.
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When coaxial cables were introduced as submarine cables, a new issue with cable-laying was encountered. These cables had periodic repeaters inline with the cable and powered through it. Repeaters overcame significant transmission problems on submarine cables. The difficulty with laying repeaters is that there is a bulge where they are spliced in to the cable and this causes problems passing through the sheave.
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The new system uses the latest in computer technology to monitor and control the movement of the carriages with comprehensive integrated safety systems to improve the smooth and safe running of the railway. New digital control panels allow clear and concise information to be relayed to the driver. A new hydraulic disc brake mounted on the main sheave wheel was installed in January 2020.
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The wood is hard and durable, attractive, reddish, and closely grained. It has been used extensively for fence posts,Qualities Required of Species for Agroforestry and Fuelwood for ornamental articles, and for high-load applications such as sheave blocks. The wood's "air dried" density is 1040 kg/m³.Aussie Fantom The tensile strength is around eighty megapascal, the transverse strength is over one hundred MPa.
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A Mirkwood appears in several places in J. R. R. Tolkien's writings, among several forests that play important roles in his storytelling. Projected into Old English, it appears as Myrcwudu in his The Lost Road, as a poem sung by Ælfwine.The Lost Road and Other Writings, King Sheave, 91 He used the name Mirkwood in another unfinished work, The Fall of Arthur.The Fall of Arthur, pp.
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Within four years there were 160 other lode or reef tin mines being worked in the neighbourhood. Hence, the Great Northern had a key role in stimulating the development of the mining industry and the economy of the Atherton Tableland. The place demonstrates rare, uncommon or endangered aspects of Queensland's cultural heritage. The mine contains the only timber headframe with sheave wheels surviving in North Queensland.
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University of California Press: Berkeley, 1982. In 1847, Rowland built the first private grist mill in the Los Angeles region, not far east of his home. Rowland must have been doing well with his cattle, crops, orchards and vineyards as he exhibited at a California State Fair in the early 1850s a sheave of wheat.Need reference from Bancroft Library, University of California at Berkeley.
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The automatic level winder fitted is designed and engineered to be compatible with the grooving on the drum. Alternatively, a sheave can be integrated and installed within the housing frame. In this case, the system can be set up anywhere around the drum. Oceanographic installations that spool rope up to 46 layers have demonstrated that level winders give synchronized and controlled spooling in the harshest, most testing conditions.
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The diameter of a loft block sheave for galvanized aircraft cable is typically at least 32 times the diameter of the cable. For example, loft blocks are typically used with GAC, but blocks may be used to facilitate flying heavier line sets (e.g., electrics). Loft blocks may be equipped with idler pulleys or sag bars to limit the sag of horizontally running lift lines on under-hung systems.
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Tanley then confronts Haru and Gobei. In the fight that follows, Haru accidentally knocks Gobei unconscious by hitting him in the head with a sheave, but forces Tanley to flee afterwards. Haru returns to attempt to rescue Alison. Using a large harpoon gun mounted on a cart, Haru shoots a harpoon through the room which inadvertently lands in the back of a truck in which Tanley is trying to escape.
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A breast derrick is a derrick without a boom with a mast constructed from two upright members. The upright members are more spread at their bottom ends than their top ends. There are crossbars to join the two members from the bottom to the top to form a mast. Without the use of boom, the top crossbar is also used to connect to a sheave or a block that is used for lifting the load.
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In a "traction" elevator, cars are pulled up by means of rolling steel ropes over a deeply grooved pulley, commonly called a sheave in the industry. The weight of the car is balanced by a counterweight. Sometimes two elevators are built so that their cars always move synchronously in opposite directions, and are each other's counterweight. The friction between the ropes and the pulley furnishes the traction which gives this type of elevator its name.
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The Puretic power block is a special kind of mechanised winch used to haul nets on fishing vessels. The power block is a large powered aluminium pulley with a hard rubber-coated sheave. While many men were needed for the back- breaking work of hauling a purse seine manually, the same work could be done by fewer men with a power block.Schmidt PG (1959) "The Puretic power block and its effect on modern purse seining".
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Antony spent the first night after turning on the electrical system watching the main entrance light, to ensure that it did not create a fire and was hence safe for his family. At some point between 1868 and 1884 a water hydraulic lift was installed by Waygood and Co., the remains of which were discovered in 2008. A wooden lift car was discovered on the ground floor and a spanning sheave in the roof space.
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The bale hoist was used to load bales of wool onto transports and is located on the rear eastern side of the woolshed, adjacent to the powerhouse. The hoist is made from steel and consists of a vertical upright with a horizontal arm at the top. The arm is supported by decorative steel bracing. Part of the hydraulic power network, the hoist had a single cable that operated through a series of sheaves; the lower sheave is now missing.
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Extra timber and lagging was placed at the entrance of the mine shaft due to fears of falling rocks. Safety concerns also led to replacement of the old pulley-sheave with a new gin-wheel. Ladder ways and timbering in the shafts were substantially upgraded as most had split due to water logging. Most of the metal infrastructure such as pipe work and bolts had corroded due to their long period of saturation, and were replaced.
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Grid-mount upright loft blocks Under-hung loft & mule blocks A block is a pulley used to support and direct lift and operating lines. A block consists of a grooved wheel, known as a sheave (pronounced "shiv"), steel side plates, spacers, shaft, flange bearings, mounting angles and clips, etc. Blocks are sized based on anticipated live loads, operating speeds, line type and other factors. Sheaves were traditionally fabricated of cast iron, but steel and nylon sheaves are now common.
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The operator would select a gear, typically 3rd. An extra control was provided to the operator to allow him to speed up and slow down the machine within the limits provided by the variable speed drive system. By decreasing the width of the sheave on the input shaft of the transmission, the belt would ride higher in the groove. This slowed the rotating speed on the input shaft of the transmission, thus slowing the ground speed for that gear.
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A torque limiter is an automatic device that protects mechanical equipment, or its work, from damage by mechanical overload. A torque limiter may limit the torque by slipping (as in a friction plate slip-clutch), or uncouple the load entirely (as in a shear pin). The action of a torque limiter is especially useful to limit any damage due to crash stops and jams. Torque limiters may be packaged as a shaft coupling or as a hub for sprocket or sheave.
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Level winders can be hydraulically or electrically driven and computer controlled, or they can be simple mechanical devices. A mechanical level winder comprises a main shaft (the lead screw) with helical screw grooving along which the rope feeder travels. The rope feeder housing includes two vertical roller bars and one horizontal roller, or alternatively a wire rope sheave. The lateral movement of the housing is generated by a chain drive sprocket ratio between drum and lead screw, as shown in the image.
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Sceaf in the boat, illustration from Fredrik Sander's 1893 edition of the Poetic Edda Sceafa ( , also spelled Scēaf, Scēf) was an ancient Lombardic king in English legend. According to his story, Sceafa appeared mysteriously as a child, coming out of the sea in an empty skiff. The name also appears in the corrupt forms Seskef, Stefius, Strephius, and Stresaeus. Though the name has historically been modernized Shava (and Latinized Scefius), J. R. R. Tolkien used the correctly constructed modern English spelling Sheave.
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A sheave can also refer to a pulley which has an adjustable operating diameter for use with a mechanical belt. This is accomplished by constructing the pulley out of several pieces. The two main "halves" of the pulley can be moved closer together or farther apart, thus altering the operational diameter. The usual construction is some sort of locking collar or set screws to secure the components, one half with a threaded central shaft and one half with a threaded center.
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Storey, p. A1. Following a settlement agreement with the GLSHS, an axe, double sheave block, signs, a valve, steering wheel, steam whistle, lumber hook, open-end wrenches, a soup bowl, an oiler, and a block pulley from Myron are now the property of the State of Michigan. Myrons artifacts are on loan to the GLSHS for display in the Great Lakes Shipwreck Museum. Myrons remains are shattered by surf and ice but she is a popular site for scuba divers.
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Cathryn Sophia is a bay filly bred in Maryland by Robert Manfuso. She was sired by Street Boss, a sprinter who won the Bing Crosby Handicap and the Triple Bend Handicap in 2008. The best of his other progeny have included Rapper Dragon, Danza (Arkansas Derby) and The Quarterback (Newmarket Handicap). Cathryn Sophia's dam Sheave was an unraced daughter of the 2003 American Horse of the Year Mineshaft, and a distant female-line descendant of the 1923 Kentucky Oaks winner Untidy.
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The minimum bend radius is in general also a function of tensile stresses, e.g., during installation, while being bent around a sheave while the fiber or cable is under tension. If no minimum bend radius is specified, one is usually safe in assuming a minimum long-term low- stress radius not less than 15 times the cable diameter, or 2 inches. Beside mechanical destruction, another reason why one should avoid excessive bending of fiber-optic cables is to minimize microbending and macrobending losses.
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A bitt and sheave was located at the keel of each davit to facilitate the lowering of boats, and the falls could be taken across the deck so that a number of men could work simultaneously on each boat and davit. They had to be lowered by hand, ideally by a team of between eight and ten men. Despite Titanic having a number of electric winches, they could only have been used to winch the lifeboats back out of the water.
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Mine shaft Warszawa, Katowice. Currently functioning as observation tower and part of the Silesian Museum The most visible feature of a traditionally-built mine shaft is the headframe (or winding tower, poppet head or pit head) which stands above the shaft. Depending on the type of hoist used, the top of the headframe will either house a hoist motor or a sheave wheel (with the hoist motor mounted on the ground). The headframe will also typically contain bins for storing ore being transferred to the processing facility.
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The first known Canadian dump truck was developed in Saint John, New Brunswick, when Robert T. Mawhinney attached a dump box to a flatbed truck in 1920. The lifting device was a winch attached to a cable that fed over sheave (pulley) mounted on a mast behind the cab. The cable was connected to the lower front end of the wooden dump box which was attached by a pivot at the back of the truck frame. The operator turned a crank to raise and lower the box.
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This limits the Giggle to 31 MPH, even down hill. However the US version is freely available in the UK, NL & Germany. With no further modification it will allow the Giggle to get to 38MPH on level roads and >40 mph down hill. The effect of removing the tiny washer that sits between the two 'cones' is a gain of 1-2 mph however research has shown that moving the washer behind the primary Sheave has the same effect and improves the geometry of the V-belt.
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Drum hoists are used for motor-assist, engaging an operating line, and dead- haul, engaging the lift lines, applications. A dead-haul drum hoist uses the single drum to support all the lift lines running from the head block of a line set. The lift lines neatly wrap and unwrap in a side-by-side arrangement on the drum as it is spun by the motor. As a lift line coils and uncoils from the drum of a drum hoist, its fleet angle (angle of a line between drum and sheave) changes.
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A one-way sprag clutch is built into the center of the upper sheave to allow the rotor system to continue to rotate in the event of engine failure, allowing the R22 to enter autorotation and land in a controlled manner. Because the main rotor has very little mass and inertia, autorotation in an R22 requires careful and proper execution to assure a successful outcome. Much time is spent in training practicing various types of autorotation. Target speed in an autorotation is and the glide ratio is approximately 4:1 in maximum-glide configuration.
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Departure zip SuperFly in Whistler, British Columbia, Canada A type of pulley with a grooved wheel known as a sheave is used in zip-lines, and the pulley turns as it travels along, thus reducing friction and enabling greater speed than would otherwise be possible. The zip-line trolley is the frame or assembly together with the pulley inside that run along the cable.Some examples can be seen here. Zip-lines also have some kind of device to allow the cargo or rider take advantage of the pulley system.
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The driver sits in the booth at the top station with full sight of both carriages (CCTV screens also allow full view of the bottom and top stations where passengers alight and disembark). The system is powered by a 60 horse power electric motor, the motor drives a David Brown 17 inch gear- box, which then rotates the 7 ft diameter main pulley or sheave wheel. Gravity aids in the movement of the carriages making the Tramway very energy efficient. In 2019 a new Programmable logic controller drive system was installed by Wheelsets UK in preparation for the 2020 season.
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Mule blocks may be permanently installed as part of counterweight rigging systems, or used for spot rigging, where they are often equipped with swivel-pivots to divert lines across a large range of angles. ;Tension block Tension blocks are single- sheave blocks located at the lower end of the arbor guide track, beneath the arbor. The operating line is reeved through the tension block from the bottom of the arbor through the rope lock. Tension blocks typically ride vertically along the arbor guide system tracks, instead of being fixed, to allow for variation in the length of the operating line.
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Coat of arms of Lethbridge The Coat of arms of Lethbridge is an official symbol of the city of Lethbridge, Alberta, Canada. It was designed by Reverend John Stanley Chivers and adopted on September 16, 1907. The shield is a roundel with three divisions, blue (azure), red (gules) and brown (ochre), with charges depicting a locomotive (for transportation), a sheave of wheat (for agriculture) and a hand with pickaxe (for coal mining) as the foundation of the early economy of the city. A circular scroll reads City of Lethbridge • 1890 • 1906, the town and city incorporation years respectively.
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As the upper section has its drive at the bottom of the section, a third cable is needed that connects the two cars via a sheave at the Summit stop. Halfway stop is also the location of the engineering depot, with access for trams from both upper and lower sections. Engineers have depot facilities for inspection and maintenance of the trams, including inspection pits. Although there is no public access to the depot, some parts of both the depot and the control room can be viewed by passengers through internal glazing in the viewing area, whilst interchanging between upper and lower sections.
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The Idlewild Lodge hotel, not to be confused with the Ski Idlewild base lodge, was a part of the Idlewild Guest Ranch and featured tennis courts, a swimming pool, a disc golf course, cross country ski trails, and the Idlewild Barn, an ice skating rink. After many years of providing novice skiers with fun and affordable skiing, Ski Idlewild closed on March 20, 1986. In 1986, the left sheave train (wheel system) of the chairlift failed and fell to the ground. There were no deaths or injuries, but four people had to be evacuated from the lift by the ski patrol.
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Jenkin had fitted her out the year before for laying the Cagliari to Malta and Corfu cables but on this occasion she was better equipped. She had a new machine for picking up the cable, and a sheave or pulley at the bows for it to run over, both designed by Jenkin, together with a variety of wooden buoys, ropes, and chains. Liddell, assisted by F. C. Webb and Fleeming Jenkin, was in charge of the expedition. Jenkin had nothing to do with the electrical work, his care being the deck machinery for raising the cable but it was a responsible job.
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The "V" shape of the belt tracks in a mating groove in the pulley (or sheave), with the result that the belt cannot slip off. The belt also tends to wedge into the groove as the load increases—the greater the load, the greater the wedging action—improving torque transmission and making the V-belt an effective solution, needing less width and tension than flat belts. V-belts trump flat belts with their small center distances and high reduction ratios. The preferred center distance is larger than the largest pulley diameter, but less than three times the sum of both pulleys.
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On April 1, 2013, a large tanker struck the bridge, causing severe structural damage and leading to a temporary closure of vehicular traffic. As the original Memorial Bridge had been closed in October 2011 and its replacement was under construction, the Piscataqua River Bridge was the only bridge between Kittery and Portsmouth remaining open. The bridge was repaired and re- opened to vehicle traffic on May 13, 2013. On August 21, 2016, the bridge became stuck in the closed position due to a mechanical failure after a shift in one of its trunnions caused a sheave and thrust block in the south tower to jam.
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A 4-wheel 'dummy' car sat on the single-track at the top of the hill, connected via a large sheave under the track to the counterweight running on a narrow-gauge track in a tunnel under the road. A tram destined for the wharf would close-up to the dummy and push it down the steep hill (gradient 1 in 8), thus raising the counterweight and being assisted in braking. The tram was then assisted up the hill by the weight of the descending counterweight via the dummy. The dummy is behind car 2010 in the photograph below, and is on display at the Sydney Tramway Museum.
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The replica ship Kalmar Nyckel 's sprit topmast A sprit topmast is a small topmast that was sometimes carried on the end of the bowsprit of a large European warship during the Age of Sail. Its purpose as initially built was to assist the spritsail (which hung below it) in bringing the around when tacking. Unlike other topmasts, the sprit topmast, because of its odd angle, lacked a sheave. Instead, the short vertical pole (the mast proper) was secured to the bowsprit with a knee, and held a platform ("top") supported underneath by trestletrees and crosstrees and further secured to the bowsprit with a series of special chain plates.
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In North America, the C3's top speed is limited by the factory via a washer on the end of the boss shaft of the V-belt transmission. This washer limits how close the belt sheaves can come together, thus limiting the potential front diameter of the belt at full throttle. Removal of the washer is possible with simple tools and will increase the top speed to an RPM limited of 40 mph, although damage caused by modification is excluded from the Yamaha warranty. In Europe the Giggle Primary sheave variator (Part No 15PE76200000 ) is different from its US C3 version (Part No 3XYE7620010).
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Trade journal coverage of V-belts in automobiles from 1916 mentioned leather as the belt material, and mentioned that the V angle was not yet well standardized. The endless rubber V-belt was developed in 1917 by John Gates of the Gates Rubber Company. Multiple-V-belt drive was first arranged a few years later by Walter Geist of the Allis- Chalmers corporation, who was inspired to replace the single rope of multi- groove-sheave rope drives with multiple V-belts running parallel. Geist filed for a patent in 1925, and Allis-Chalmers began marketing the drive under the "Texrope" brand; the patent was granted in 1928 ().
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This can be used by removing the driving pins from the rear wheels, allowing the drive train to power the winch drum instead of the wheels. James Boydell worked with the British steam traction engine manufacturer Charles Burrell & Sons to produce road haulage engines from 1856 that used his Dreadnaught Wheels which were particularly suited to bad roads or off-road use. A number of road locomotives are fitted with a crane boom on the front. The boom pivot is mounted on the front axle assembly and a small winch is mounted on an extension to the smokebox in front of the chimney, the cable passing over a sheave at the top of the boom arm.
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Typical K values are 1.04 for roller bearing sheaves and 1.09 for plain bearing sheaves (with wire rope). The increased force produced by a tackle is offset by both the increased length of rope needed and the friction in the system. In order to raise a block and tackle with a mechanical advantage of 6 a distance of 1 metre, it is necessary to pull 6 metres of rope through the blocks. Frictional losses also mean there is a practical point at which the benefit of adding a further sheave is offset by the incremental increase in friction which would require additional force to be applied in order to lift the load.
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An F/A-18 Hornet engages the #4 wire, with the white retractable deck sheave in the foreground. Each pendant has its own engine systems that absorb and dispel the energies developed when a landing aircraft is arrested. On American Nimitz-class carriers, hydro-pneumatic systems are used, each weighing , wherein oil is hydraulically forced out of a cylinder by a ram connected to the purchase cable, through a control valve. A major development in arresting gear was the constant runout control valve, which controls the fluid flow from the engine cylinder to the accumulator and is designed to stop all aircraft with the same amount of runout regardless of mass and speed.
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A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable or belt, or transfer of power between the shaft and cable or belt. In the case of a pulley supported by a frame or shell that does not transfer power to a shaft, but is used to guide the cable or exert a force, the supporting shell is called a block, and the pulley may be called a sheave. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt. The drive element of a pulley system can be a rope, cable, belt, or chain.
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The old coal mining sheave wheel, now featured in the centre of Radstock, in front of the Radstock Museum Map of the Somerset Coalfields The Somerset Coalfield in northern Somerset, England is an area where coal was mined from the 15th century until 1973. It is part of a larger coalfield which stretched into southern Gloucestershire. The Somerset coalfield stretched from Cromhall in the north to the Mendip Hills in the south, and from Bath in the east to Nailsea in the west, a total area of about . Most of the pits on the coalfield were concentrated in the Cam Brook, Wellow Brook and Nettlebridge Valleys and around Radstock and Farrington Gurney.
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"Hookup man" ensures that aircraft launchbar (left) and holdback fitting (right) are properly seated in the catapult. ABEs operate and perform maintenance on steam catapults, barricades, arresting gear, and associated equipment ashore and afloat; operate catapult hydraulic systems, retraction engines, water brakes, jet blast deflectors, deckedge and Integrated Catapult Control Stations (ICCS), and jet blast deflector control panels; arresting gear engines, sheave dampers, deckedge control station, and associated equipment; perform aircraft handling duties related to the operation of aircraft launching and recovery equipment. Most of the work in this rating is performed outdoors on the deck of aircraft carriers, in all climatic conditions, in fast-paced and often potentially hazardous environments. ABEs work closely with others in aviation ratings.
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The hand spinning movement that he initiated as a part of the Indian freedom struggle has made the handwoven cloth known as "Khadi" made from handspun cotton yarn world-famous. Women spinners of cotton yarn still continue to work to produce handspun yarn for the weaving of Khadi in Ponduru, a village in South India. A great wheel (also called a wool wheel, high wheel or walking wheel) is advantageous when using the long-draw technique to spin wool or cotton because the high ratio between the large wheel and the whorl (sheave) enables the spinner to turn the bobbin faster, thus significantly speeding up production.Brown, Rachel, ‘’The Weaving, Spinning and Dyeing Book’’, pp.
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J. R. R. Tolkien treated Sceaf in a poem "King Sheave" which was published after his death in "The Lost Road" in The Lost Road and Other Writings and very slightly revised and printed as prose in "The Notion Club Papers (Part Two)" in Sauron Defeated. In Tolkien's treatment, a ship drifts to the land of the Longobards in the north. It beaches itself and the folk of that country enter and found a young and handsome boy with dark hair asleep with a "sheaf of corn" as his pillow and a harp beside him. The boy awoke the following day and sang a song in an unknown tongue which drove away all terror from the hearts of those who heard.
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Flat belt on a belt pulley Belt and pulley system Cone pulley driven from above by a line shaft A belt and pulley system is characterized by two or more pulleys in common to a belt. This allows for mechanical power, torque, and speed to be transmitted across axles. If the pulleys are of differing diameters, a mechanical advantage is realized. A belt drive is analogous to that of a chain drive; however, a belt sheave may be smooth (devoid of discrete interlocking members as would be found on a chain sprocket, spur gear, or timing belt) so that the mechanical advantage is approximately given by the ratio of the pitch diameter of the sheaves only, not fixed exactly by the ratio of teeth as with gears and sprockets.
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