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Tugboat Hitch
The Tugboat hitch (a.k.a. Backhanded mooring hitch or Lighterman's Hitch) is a knot ideal for heavy towing, or making fast to a post, bollard, or winch. It is easy to release, even under great Structural load, load. Tying To tie, take a single turn or a round turn around the post. Pass a Bight (knot), bight under the standing part, then drop the bight over the top of the post. Then make a bight in the rope on the other side of the standing part and drop it over the post. Note that in each placement of a bight over the post, the end's side of the bight should lead to the side away from the standing part—this will make casting off easier. Continue this repetition as necessary until secure (usually three bights). Finish by half-hitching a bight around the standing part or a round turn about the post. With heavy loads, it is important to have made enough bights and turns to reduce force on the final turns or a hitch—otherwise, it will be difficult to untie (a hitch) or may slip. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winch
A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a spool (or drum) attached to a hand crank. Traditionally, winches on ships accumulated wire or rope on the drum; those that do not accumulate, and instead pass on the wire/rope (see yacht photo above), are called capstans. Despite this, sailboat capstans are most often referred to as winches. Winches are the basis of such machines as tow trucks, steam shovels and elevators. More complex designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. It might include a solenoid brake and/or a Mechanical brake stretch wrapper, mechanical brake or ratchet (device), ratchet and pawl which prevents it unwinding unless the pawl is retracted. The rope may be stored on the winch. When trimming a line on a sailboat, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knot
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ''bend'' fastens two ends of a rope to each another; a ''loop knot'' is any knot creating a loop; and ''splice'' denotes any multi-strand knot, including bends and loops. A knot may also refer, in the strictest sense, to a stopper or knob at the end of a rope to keep that end from slipping through a grommet or eye. Knots have excited interest since ancient times for their practical uses, as well as their topological intricacy, studied in the area of mathematics known as knot theory. History Knots and knotting have been used and studied throughout history. For example, Chinese knotting is a decorative handicraft art that began as a form of Chinese folk art in the Tang and Song Dynasty (960–1279 AD) in China, later popularized in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bollard
A bollard is a sturdy, short, vertical post. The term originally referred to a post on a ship or quay used principally for mooring boats. It now also refers to posts installed to control road traffic and posts designed to prevent automotive vehicles from colliding or crashing into pedestrians and structures, whether intentional from ram-raids and vehicle-ramming attacks, or unintentional losses of control. Etymology The term is probably related to bole, meaning a tree trunk. The earliest citation given by the ''Oxford English Dictionary'' (referring to a maritime bollard) dates from 1844, although a reference in the ''Caledonian Mercury'' in 1817 describes bollards as huge posts. History Wooden posts were used for basic traffic management from at least the beginning of the 18th century. An early well-documented case is that of the "two oak-posts" set up next to the medieval Eleanor cross at Waltham Cross, Hertfordshire, in 1721, at the expense of the Society of Antiqua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Load
A structural load or structural action is a force, deformation, or acceleration applied to structural elements. A load causes stress, deformation, and displacement in a structure. Structural analysis, a discipline in engineering, analyzes the effects of loads on structures and structural elements. Excess load may cause structural failure, so this should be considered and controlled during the design of a structure. Particular mechanical structures—such as aircraft, satellites, rockets, space stations, ships, and submarines—are subject to their own particular structural loads and actions. Engineers often evaluate structural loads based upon published regulations, contracts, or specifications. Accepted technical standards are used for acceptance testing and inspection. Types Dead loads are static forces that are relatively constant for an extended time. They can be in tension or compression. The term can refer to a laboratory test method or to the normal usage of a material ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Round Turn
A turn is one round of rope on a pin or cleat, or one round of a coil. Turns can be made around various objects, through rings, or around the standing part of the rope itself or another rope. A turn also denotes a component of a knot. When the legs of a loop are brought together and crossed the rope has taken a turn. One distinguishes between single turn, round turn, and two round turns depending on the number of revolutions around an object. The benefit of round turns is best understood from the capstan equation. Riding turn A riding turn is a section of rope that passes on top of another section of rope, often parallel or at only a slight angle to the section below. Examples of riding turns can be seen in both the constrictor knot and the strangle knot. The second course of wrappings in some seizing knots can be referred to as riding turns. The formation of an unintentional riding turn on a sailing winch can cause it to jam. Single hitch A single hitch is a type of knot. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bight (knot)
In knot tying, a bight is a curved section or slack part between the two ends of a rope, string, or yarn.. "Any slack part of a rope between the two ends, particularly when curved or looped." A knot that can be tied using only the bight of a rope, without access to the ends, is described as in the bight. The term "bight" is also used in a more specific way when describing Turk's head knots, indicating how many repetitions of braiding are made in the circuit of a given knot. Bight vs. open loop Sources differ on whether an open loop or U-shaped curve in a rope qualifies as a bight. treats bights and loops as distinct, stating that a curve "no narrower than a semicircle" is a bight, while an open loop is a curve "narrower than a bight but with separated ends". However, ''The Illustrated Encyclopedia of Knots'' (2002) states: "Any section of line that is bent into a U-shape is a bight." Slipped knot In order to make a slipped knot (also slipped loop and quick release knot), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half-hitch
The half hitch is a simple overhand knot, where the working end of a line is brought over and under the standing part. Insecure on its own, it is a valuable component of a wide variety of useful and reliable hitches, bends, and knots. Two successive half hitches tied around an object makes up the common clove hitch. Two successive half hitches tied around the standing part of a rope is known as two half-hitches or double half hitch. One instance where a half hitch stands on its own without additional embellishment is when added to a timber hitch to help stabilize a load in the direction of pull. A timber hitch is tied on the far end of the load to bind it securely and a half hitch made at the forward end to serve as a guide for the rope. In this instance, the half hitch combined with a timber hitch is known as a killick hitch or kelleg hitch. The knot is attractive to the eye and so is used decoratively for French whipping which is also known as ''half hitch whipping''. Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
