Types of ropes and cables. vegetable ropes

Cables (ropes) are products twisted from steel wires or twisted from plant and artificial fibers. According to the material, the cables are divided into vegetable, steel (wire), combined and synthetic.

They are made from plant fiber processed in an appropriate way. Depending on the source material, plant cables are hemp, manila and sisal.

Hemp cables made from hemp fibers - hemp. Hemp can be used in its pure form (white ropes) and tarred (tarred ropes). The grinding of hemp protects the cable from moisture and rapid decay, but its strength is somewhat reduced. Hemp cables are strong and elastic, but they absorb moisture strongly, so they sink in water, and in cold and wet weather they become heavy and stiff.

manila cables, made from the fibers of the stems and leaves of the banana tree, very convenient for use on ships. The peculiarity of these cables is their low hygroscopicity, due to which they do not sink in water. These cables are the strongest of the vegetable cables and are distinguished by their flexibility and considerable elasticity.

Sisal ropes made from the fibers of the leaves of the tropical agave plant. These cables are inferior in strength to hemp. They have a high rigidity, as a result of which they wear out quickly.

Vegetable cables are made as follows. First, the fiber is twisted into kabolki. Then a strand is obtained from several kaboloks. Three or four strands twisted together form a cable, which is called a cable work cable (Fig. 1, a). Several cables (three or four) of cable work, twisted together, form a cable work cable (from-gate cable). The cables used for cable work are called strands (Fig. 1, b)

Rice. 1 Vegetable cables a - cable work, b - cable work, c - direct descent, d - reverse descent, 1 - cables, 2 - strands, 3 - strandy

In order for the cable not to untwist and keep a constant shape, constituent elements(cable strands, strands and cables in general) are twisted in different directions. Usually the fibers are twisted into cables clockwise so that the coils go from left to top to the right, the cables into strands in reverse side, and the strand into the cable again clockwise. In this direction, the lay turns out to be a cable of direct descent (Z-shaped) (Fig. 1, V). In some cases, apply reverse direction lays. Such cables are called reverse descent cables (S-shaped) (Fig. 1, G).

Braided cables have also been used on ships, which consist of one loosely twisted strand covered with a braid of linen threads. These cables stretch a little and do not twist, therefore they are used for signal halyards and laglins of outboard lags.

The thickness of plant cables is measured along the circumference. Depending on it, these cables have special names. So, cables up to 25 mm thick are called lines, from 100 to 150 mm - pearls, from 150 to 350 mm - cable and over 350 mm - ropes (cables with a circumference of 25-100 mm do not have a special name).

Rice. 2 Steel cables of various lay: a - single; b - double; c - triple

steel cables made of steel, usually galvanized, wire with a diameter of 0.2-5 mm. Depending on the number of layers, single, double and triple lay cables are distinguished (Fig. 2). The easiest way is to make a single lay steel cable. In this case, several wires are twisted directly into a cable.

Such single-strand cables are called spiral. But more often and in a large assortment, double-lay cables are made: the wire is first twisted into strands, and then several strands are twisted into a cable. If several such cables are twisted together, then a triple lay cable will be obtained.

Multi-strand cables are twisted around the central core (Fig. 3), which is used as steel wire or organic fibers. The core, filling the void inside the cable, prevents the strands from falling to the center, and the organic core containing anti-corrosion grease, in addition, protects the cable wire from rusting, which increases its service life. In addition to the center core, some cables may have an organic core within each strand.

big practical value has a classification of cables according to their flexibility. The most rigid are single-strand spiral cables. Rigid cables include cables with a wire core, and cables with a central organic core are semi-rigid. Flexible cables have several organic cores. Triple lay ropes have the greatest flexibility.

To designate grades of steel cables adopted digital system, according to which each cable is marked with a product of numbers: the first of them indicates the number of strands in the cable, the second - the number of wires in each strand. When marking a triple lay cable, one more factor is added in front, which indicates the number of strands in the cable. The number of organic cores in the cable is indicated by the last digit.

Rice. 3 Steel cables with a core: a - wire, b - synthetic, c - organic

6 X 24 + 7 means a double lay cable consisting of 6 strands, each strand of 24 wires, and having 7 organic cores. A six-strand triple lay cable, each strand of which is twisted of 7 strands of 19 wires and has one organic core, will be designated: 6 X 7 X 19 + 1.

Combined cables have strands consisting of galvanized steel wires covered with vegetable yarn.

Synthetic ropes they are made from artificial fibers, which include kapron, nylon, curalon and polypropylene, the most common now. These cables in their strength, elasticity, flexibility and durability are much superior to the best vegetable ones. They are not subject to rotting and mold, almost do not lend themselves to the action of oil, oils, alkalis and acids. For ship work most often, steeper three-strand synthetic cables are used, and for mooring ends it is allowed to use braided eight-strand synthetic cables.

The use of cables on ships requires knowledge of their main characteristics, of which strength is the most important. The strength of the cable is characterized by its breaking force, which is understood as the minimum load that breaks the cable. The breaking strength of the rope depends on its diameter and design, type of lay and material, wire diameter, steel quality, etc.

The values ​​of the breaking force of the cables are given in the state standards. For practical purposes, it is often sufficient to know the approximate value of the breaking force, which can be determined from various empirical formulas.

For example, breaking force R(in N) and mass G(in kg) 100 normal three-strand manila rope of cable work is determined by:

Where f is an empirical coefficient, the magnitude of which varies up to 4 when the cable circumference changes from 30 to 350 mm. More precisely, this coefficient can be determined by the formula

f \u003d 650 - 0, 75 C 100

WITH— rope circumference, mm.

Table 1

The breaking strength of other types of plant ropes can be determined using the same formulas with the correction indicated below (in % of the calculated value R) :

• Manila increased strength + 30;
• Sisal normal - 30;
• The same increased strength - 0;
• Hemp white, normal - 20;
• Same special + 5;
• The same tarred normal - 25;
• Same special.

Synthetic ropes have significantly higher strength. The breaking force of the curalon cable is 1.5 times, and of nylon and kapron - more than 2.5 times higher than that of manila. At the same time, the mass of synthetic cables is 10% less than vegetable ones.

Breaking force and mass of steel cables can be determined:

Wherek Andk 1 — empirical coefficients, the value of which for various types of cables is indicated in Table. 1;

d — cable diameter, mm.

In order to choose the right cable for work, it is necessary to know not only the breaking force, but also its working strength (permissible tension). Working strength - the load at which the cable can work under given conditions for a long time without violating the integrity of individual elements and the entire cable. Working strength R(in Newtons) is only a part of the breaking force and is determined by:

Where n is the safety factor.

For cables used on ships, n usually taken equal to 6. More precisely, it can be chosen taking into account the purpose, operating conditions and type of cable. Yes, for standing rigging P drops to 4, in devices for lifting people it rises to 14.

Example 1. Normal three-strand Manil mooring cable, circumference 250 mm. Calculate the breaking force and working strength of 100 m of cable and the weight of the cable coil of 200 m.

• We find the coefficient of efficiency f \u003d 650 - 0, 75 × 250 100 \u003d 4, 625;
• We define R = 4, 625 × 250 2 = 289062, 5 H;
• Then we determine Р = 29062, 5 6 = 48177, 1 H;
• Weight of 100 m of cable G = 0.007-250 2 = 437.5 kg. The mass of a bay of 200 m will be 2 times larger, i.e. 875 kg.

Example 2 Steel flexible towing cable with a diameter of 60 mm. Calculate the breaking force and working strength of 100 m of the cable and the weight of the coil of 500 m of this cable.

• We choose from the table. 1 value & = 350 and k1 =0,3;
• We define R = 350 . 60 2 \u003d 1,260,000 N;
• P and n I in n \u003d 5, we get P \u003d 1260000 5 \u003d 252000 H;
• Weight of 100 m rope G= 0.3. 60 2 \u003d 1080 kg, and a bay of 500 m has G — 5-1080 = 5400 kg.

The supply of ships with cables is carried out in accordance with the Rules for the Classification and Construction sea ​​vessels Register of the USSR.

The strength and durability of cables depends not only on their design and quality, but also on proper operation, storage and care. A good cable can quickly become unusable if you do not follow the basic rules of technical operation and use it in inappropriate conditions.

Identification of the good quality of the cable depends on the correct reception. Upon receipt of the cable, carefully inspect it and check the basic design data and the presence of a certificate with a tag. When inspecting steel cables, they check the integrity of the galvanization, the presence of rust, the safety of the wire and the tightness of the wires in the strands. When accepting vegetable ropes, it is necessary to pay attention to their smell and color, since a musty smell indicates the presence of rot and mold.

The pitched cable should be of a uniform light brown color, free of spots, not sticky to the hands, and not crackle when unfolded. The stickiness of the cable indicates an excessive amount of resin, and a dry crackle indicates that the cable is stale.

The safety of the cable is largely ensured by the correct methods of opening the coils (Fig. 4), which do not allow the formation of loops and creases (pegs), since the creases cause significant local deformation of the cables and rupture of individual wires, and also make it difficult to work with cables.

When unraveling, the plant cable bay is placed on edge, the strapping is removed and, having passed the inner end of the cable through the inner cavity of the bay, they unravel it, holding the outer hoses with their hands.

To unravel the steel cable coil, holding the coil by the extreme hoses, roll it out on the deck and at the same time pull the running end. A thick steel cable is usually received on a ship wound on a drum. In this case, it is best to unwind the cable from a rotating drum, setting it in a horizontal position on two supports.

Rice. 4 Rope unraveling: a - vegetable; b and c - steel

The cables loosened from the bay should be stretched along the deck so that they straighten out, and then cut into pieces of the desired length. In order to prevent the cable from untwisting at the place of the cut, on both sides of this place it is preliminarily tied with a soft wire or a cable, stamps are applied. The cut cable is wound on views or stored in small bays. From the action of moisture, the cable protects the cover, which is put on the view. In good weather, the cover must be removed to dry the cable.

Vegetable cables are usually stored in small, loosely laid bays. The cables are laid in a coil, i.e. direct descent cables are clockwise, and reverse descent and cable work cables are counterclockwise. To protect against the action of moisture, the bays of the plant cable are suspended or laid on gratings (banquettes).

During rain or fresh weather, the bays should be covered with tarpaulins or covers. All unused cables should be stored in dry, well ventilated areas. From time to time, the cables must be thoroughly ventilated, for which they should be hung on handrails, between masts, or in other convenient places.

Cables that were in use are well dried before being laid in coils. Plant cables that are wet in sea water should be washed with fresh water before drying. For washing large cables, you can use the ship's entrances to the mouths of the rivers, where the cable can be washed overboard in river water.

Synthetic cables are not afraid of moisture, and drying them is optional, but it is impossible to wind a wet cable around a view. The cable should be dried in the shade, as it deteriorates from the action of sunlight. If dirty, the cable can be washed sea ​​water. Synthetic ropes are very sensitive to abrasion and melting, so drum surfaces must be smooth.

During operation, static electricity accumulates on the surface of synthetic cables, which can cause sparks to form. Therefore, new synthetic cables can be used on tankers only after antistatic treatment, soaking for a day in sea water with a salinity of at least 20%, or in a specially prepared saline solution (20 kg table salt per 1 m 3 of water). During operation, the cables must be periodically, at least 1 time in 2 months. roll on the deck with salty sea water, about which they make an entry in the logbook.

Careful care is also required for combined cables with a shirt made of vegetable cables. These cables must not be laid in coils damp or wet, since the moisture remaining in the jacket can cause intense corrosion of the wire.

Steel cables should be systematically lubricated (tied). This not only protects the cable from corrosion, but by reducing friction between the wires, it helps to reduce wear. Rope grease NMZ-Z or ZZT is usually used as a lubricant. Netted cables must be lubricated with grease at least once a month. Range composition: 87% grease, 10% bitumen, 3% graphite.

There are about four dozen varieties of steel rope on the modern market. All of them are made in strict accordance with GOSTs, but at the same time they can differ greatly from each other. To understand this, it is necessary to study the classification of ropes.

Selection Criteria for Steel Ropes

People who constantly work with metal cables and ropes have practically no problems with their choice. Trouble begins when a non-standard rope is required for the job. In this case, you need to use GOST, which describes the exact classification.

According to this GOST, all metal ropes can differ in such parameters as:

• construction type;
• type cross section wires;
• type, method and direction of lay details;
• core material;
• degree of balance and torsion;
• maximum strength level;
• mechanical properties wires;
• appointment.

Home design feature of all steel ropes is the number of strands (braids) and the way they are twisted. According to this feature, the lay can be single, double or even triple. In the first case, the wire is twisted in a spiral shape in one or more layers. If the cable is still covered with shaped wire from above, then it is called closed.

Double-lay ropes consist of thin single strands, the number of which can be up to six. They are also used for the manufacture of triple lay ropes.

Classification of ropes by lay parameters

A twist is the process of twisting strands of a metal rope. The strands can touch each other pointwise, linearly or in a combined way. Strands of different layers may have the same or different diameters. If filling wires are laid between them, then the rope is marked as "LK-Z". In the event that wires of different diameters are laid between the strands, this is an LK-RO rope.

Sometimes during the production process, the wire and strands go through a preliminary deformation. This is done in order to obtain a non-twisting rope. If the strands fall apart immediately after removing the retaining ties, then you have an unwinding rope in front of you.

The lay direction of the metal rope can be right or left. This takes into account not only the position of the strands of the outer layer, but also their position in relation to the rope itself. On this basis, the twist can be:

• cross,
• unilateral,
• combined.

Types of ropes by core type

The core is located in the very center of the steel rope and is necessary to give it the necessary flexibility and strength. It is usually produced using metal or organic materials. Ropes with a metal core are used to solve problems such as:

• increase in structural strength,
• increase in wear-resistant properties when working at high temperatures,
• reduction of structural elongations under tension.

The organic core of metal ropes can be made from natural or synthetic materials. Usually these are cotton threads, polyethylene, nylon and more.

Types of ropes according to the degree of balance and twist

The balance of a metal rope is determined by whether straightening was used in the process of its production. It takes stress off the strands when they are hung horizontally. It is thanks to this that the product retains its straightness.

If, being in a horizontal position, the rope at the end is twisted into a ring, it means that straightening was not carried out during its production.

To determine the degree of twist of the rope, you need to study the direction of all the strands of the lay. They can have the same direction in all layers (rotating) or the opposite direction in different layers (low-rotating).

Other characteristics of metal ropes

When buying metal cables, you need to pay attention to the quality of the wire, as well as the accuracy of manufacturing. Typically, they are produced using normal, high or high quality. It can be coated with a galvanized or polymer layer, which protects it from medium, hard or especially hard aggressive environments.

It can be used to lift and transport goods only, or both goods and people. To determine its strength characteristics, you need to pay attention to the latest value in the marking. It can be in the range of 1370-1770 N/mm2. The higher the strength characteristics of a metal rope, the more load it can withstand.

§ 63. Means of communication and signaling on the water.

On small vessels, communications and signaling are necessary to communicate with the shore and other vessels, to send distress signals.

All types of means of communication or signaling on small vessels are divided into three main types: visual, sound, radio engineering.

1. Visual alarm.

The means of visual communication include flag and light signaling.

A. Flag signaling.

Flag semaphore (Fig. 148, a) is the most common and affordable type of communication. Its essence is that each letter of the Russian alphabet corresponds to a certain position of the hands. In the semaphore alphabet, there are 29 alphabetic characters, 8 service characters and 4 change of place characters. In order to use a flag semaphore, an amateur boatmaster must know it well, and on a vessel at sea, have two brightly colored flags nailed to the handles for ease of use. You must also have a spare pair of semaphore flags.

Signal flags (see annex) are used for communication and signaling with posts, lighthouses and passing ships. If the amateur navigator does not know by heart the meaning of each flag or combination of flags, then the ship must have a table where these values ​​would be written out. The combinations of flags given in the appendix, the navigator in navigation must know by heart and have prepared combinations on the ship in order to quickly report a warning or distress signal at the right time or read the signal raised by another ship.

Single Flag Signal Values

A - "I do speed tests"

B - "I'm unloading (unloading) explosive"

IN - "I need health care»

G - "I need a pilot"

D - “Stay away from me. I manage with difficulty"

E - "I am steering my course to the right"

AND - "I need help"

W - Coast Station Call Alert

AND - "I'm going to make a semaphore message"

TO - "Stop your ship immediately"

L - “Stop. I have an important message"

M - "I have a doctor on board"

Rice. 148 a- flag semaphore alphabet;

H - "No", negative

ABOUT - "Man overboard"

P - At sea: "Your lights are out." In the port: "The crew to get on the ship"

R - "My ship is not moving"

Rice. 148 b- individual signs and tricks

WITH - "My cars are running full speed backwards"

T - "Don't Cross My Course"

At - "You are walking into danger."

F - “I am not in control. Keep in touch with me"

X - "I have a pilot on board"

C - "Yes", affirmative

SCH - "My ship is not infected"

B - "Stop your actions, follow me"

S - "I'm delivering mail"

B. Light signaling.

Light signaling is used at night, when other means of communication cannot transmit a message. Each letter of the Russian alphabet is assigned a certain combination, consisting of a set of dots and dashes transmitted by a searchlight, a signal device or a cloak.

The point is transmitted by short pressing the key that closes the electrical circuit. The dash should be three times the length of the dot.

In the absence of electric lighting, the message can be transmitted with an electric pocket torch or oil torch, covering the light with the palm of your hand or cap.

Rice. 149. Use of a signaling mirror. A- alignment of the sunspot; b - signaling

Light signaling also includes a light signaling mirror (heliograph), which is a device that allows you to apply the rays reflected by the mirror in the form of light signals at a distance of up to 20 miles. This device is based on pointing the reflection of the solar disk ("bunny") at the object of interest. The signal mirror consists of two metal plates fastened on a hinge, the surface of one of which is chrome-plated and polished. The plate has a sighting hole. To give signals, the mirror should be held in the hand in such a way that the vessel or aircraft that is giving the signal can be seen through its sighting hole on the upper sash (Fig. 149, a). In order for the “bunny” to fall on the target and notice your signal on the ship or aircraft, it is necessary to turn the mirror so that the beam that passes through the sighting hole and is reflected from the lower sash onto the inner surface of the upper sash in the form of a light circle coincides with the sighting hole (Fig. 149.6).

To prevent the mirror from falling into the water, it must have a cord that is worn around the neck during signaling.

Pyrotechnic signaling or pyrotechnic means are used to signal the position of a vessel or in distress. Pyrotechnics are divided into day (thick orange smoke) and night (bright stars or flames).

Boat parachute rocket RB-40Sh takes off at a height of at least 200 m, burns bright red and slowly descends by parachute. Duration of burning 35 sec. The visibility range of the signal is 10-15 miles.

A night signal cartridge, commonly referred to as a "flare", is held in the hands when burned and produces a torch of red, blue, or white fire.

The cartridges are respectively designated F-2K, F-2G and F-2B.

Red fire flares are for distress signals, white flares for drawing attention, blue - to call the pilot. The duration of the signal for cartridges of red and blue fire is at least 60 seconds, for white fire - 30 seconds. Visibility range 5 miles.

The flares are safe to handle and are not blown out by the wind.

The day signal cartridge, when fired, emits orange smoke, which is visible from a distance of 3-4 miles. The burning time of the cartridge is not less than 30 seconds.

Floating smoke grenades are effectively used during daylight hours. Thick orange smoke, even in clear and calm weather, is visible for at least 5 miles. Smoke formation occurs within 5 minutes. and runs without an open flame.

Pyrotechnic cartridges are reliable, and preparation for the action of the aforementioned pyrotechnic means takes no more than 7-10 seconds.

To give a signal, the cap of the cartridge is unscrewed and the ring with the cord is pulled out with a sharp movement. All cartridges when giving a signal must be kept away from you downwind.

Visual signaling also includes water surface dyes that are clearly visible from an aircraft.

Dyes include packages with dyes - fluorescein or uranine brand "A", coloring the surface of the water on an area of ​​up to 50 m 2 in yellow-green color. The visibility range of such a spot from an aircraft reaches 15-20 km.

It is not necessary to have all the above pyrotechnic signaling devices when sailing in open waters, but at least 1-2 devices from each of the above pyrotechnic groups must be on board. It is possible to have one remedy reliably replacing another. This is necessary for the case of a distress call. To avoid a fire, pyrotechnic signals should only be lit overboard on the leeward side of the vessel.

2. Audible alarm.

On small boats, all types of car signals, whistles, signal horns, bells are applicable to give signals, attract attention, indicate their location in the fog (poor visibility), in the absence of visual signaling. Car horn 1 mile, horn 0.5 mile, whistle twice as far as voice, electric, air sirens and steam horns 2 km.

The P12 Distress Cartridge emits a signaling sound audible in calm weather at a distance of at least 5 miles.

3. Radio signaling.

An emergency portable boat radio station "Shlyup" and an emergency aircraft radio station "Kedr-S" can be used as a radio-technical signaling device for sending distress signals on small vessels, which can operate both from an automatic alarm and distress sensor, and from a manual key. The receiver of the Sloop radio station has two wavelength ranges: 400-550 kHz and 600-9000 kHz. Signal transmission can be carried out on waves with frequencies of 500, 6273 and 8364 kHz. The station has the shape of a cylinder with a diameter of 280 mm, height 500 mm, weighs 25 kg and is powered by a hand generator.

Radio station "Kedr-S" operates at frequencies 500, 2232, 4465, 8928 and 13392 kHz. In a set weighing 25 kg There are two types of antennas. Power is supplied by dry batteries.

An emergency portable radio station of the "Raft" type, designed to send and receive telegraph and telephone call and distress signals, as well as to receive signals in the medium ranges (100-550 kHz), intermediate (1605-2800 kHz) and short (6000-8000 kHz) waves. There is an automatic alarm sensor.

The radio station is powered by a hand generator. The receiver can also be powered by water-filled batteries of the "Dymok" type, which are included in the supply of life-saving equipment. The radio station consumes no more than 35 tue, and when receiving no more than 6 Tue. The amount of electricity consumed from water-filled batteries when receiving does not exceed 1.5 Tue.

"Raft" weighs 23 kg, has dimensions 270X300X415 mm and can operate with a 6m telescopic antenna, a 9m mast and a 100m box kite.

Radar passive reflectors installed on sailing, rowing, wooden, plastic boats also refer to the means of signaling, by which navigators of ships where ships are installed radar stations, detect small vessels. The installation of passive radar reflectors is necessary for the timely detection of a small vessel by ships big fleet both on open water spaces and on inland waterways. There are many cases when the timely detection of a small vessel in poor visibility and in fog prevented a collision between small vessels and large ones when the latter changed its course.

The presence of passive radar reflectors on small boats is of decisive importance in rescue operations to search for ships carried away at sea.

The passive radar reflector consists of three metal exactly mutually perpendicular disks with a diameter of 240 mm and thickness 1 mm. TO one of the discs is attached to a steel tube with a diameter of 50 mm and length 130 mm. It is mounted on a wooden two-meter rod, which, together with the reflector, is installed vertically on the mast.

§ 64. Rigging work on the ship.

Rice. 150. Cables: a - three-strand and four-strand cables of cable work; b- hemp cable work cable and its parts

Rigging works are called all work with cables in the manufacture of rigging, tugs, mooring ends, etc. Any rope on a ship is called a cable.

Cables are vegetable, steel and synthetic. Vegetable cables are hemp, manila, sisal and cotton (Fig. 150). Hemp rope can be white and tarred. A tarred rope is more durable, but slightly weaker than white. Of the vegetable cables, the best for mooring a ship are hemp white or resin. Vegetable cables are afraid of soot, high temperatures, and oils. If the white cable in the middle is light, then its quality is good, if it is brown, then the cable is rotten.

Rice. 151. Steel cables: a - hard; b - semi-rigid; V- flexible; G- benzel

Steel cables are made from galvanized wires (Fig. 151). Having a greater strength than vegetable, these cables are more rigid, and therefore not so easy to use. The more wires in the cable, the softer, more elastic it is, the more convenient it is to work with it.

The cables require care: vegetable cables are dried after work, steel cables are lubricated with grease or used oil once a month. Acids and alkalis spoil any cables.

Rice. 152. rigging tool 1 - pile, 2 - mushkel, 3 - half-mushkel, 4 - draek, 5 - spatula, 6 - knife

The rigging tool is used when working with cables (Fig. 152). With the help of a pile, strands of a cable break through when sealing fires, cable connections. Draek is used for tightening benzels, lashings and beating around rigging lights and knots. Mushkel - a wooden mallet for beating cables. Gardaman - a leather "thimble" with a steel or copper head in the palm of your hand.

In addition, the set of rigging tools includes a knife, chisel, hammer and spatula.

2. Knots.

Knots serve to bind cables and fasten them to any objects, equipment, etc. They must quickly knit and untie, but not spontaneously unravel. The main nodes (Fig. 153).

A straight knot is used to fasten two ends of a small diameter cable (with a slight tensile force to avoid tightening the knot).

The reef knot is used when a quick return of the connected gear is required, for which you need to pull the free end of the cable.

Rice. 153 Marine knots: A- straight, b - reef, V- noose, G - bleached; d- a simple bayonet; e- locking knot; and- boat knot; h - hook knot; and - sheet (left) and bramshkot (right); k - flat knot; l - towing, m- buoy knot

The choke is used to quickly secure the cable to logs and other round surfaces when towing. For the strength of the knot and to reduce slip on a smooth round surface, one or two hoses are additionally made.

A faded knot is knitted when there is an assumption that the noose will slip.

A simple bayonet is used when fastening mooring lines to eyelets and poles. A variety of a simple bayonet is a bayonet with two hoses - it does not creep and does not tighten.

The locking knot is used when fastening the boat bells, when one towing cable is fed to several boats.

The boat knot is used to attach the boat, for example, when towing.

The hook knot is knitted for laying a vegetable cable on the hook.

The clew knot is used for knitting sheets into the clews of sails. A variation of it is the bramshkot knot, which is used for heavier loads.

A flat knot is used for tying cables of various thicknesses, for example, a conductor with a tug (more often a knotted knot with a reverse loop for untying is used for this).

The towing knot is used for laying the towing line on the hook.

The buoy knot is used when knitting a buoy for the anchor trend.

3. Splash and lights.

Splashes are used to splice two cables. They are short and long or accelerating. A short mold gives a slight thickening at the splicing site. To splice two cables with a short splash, the strands of both ends are unraveled (Fig. 154, a). A mark is applied to the cable, which protects the cable from unraveling.

Strands of one cable are inserted crosswise into the strands of another. Turning the cable in the sun, they break the running strand of one cable under the oncoming strand of the other so that when tightened, they press each other. Usually three punches are made for each strand, then cut off half a strand and punched one more time. To splice two cables with a long (accelerating) splash (Fig. 154, b) the cable is unraveled by one to one and a half meters and stamps are applied. Then one strand is twisted, and a strand of another cable is twisted in its place. The remaining two intact strands are tied together, and the ends of the strands are cut off. To splice two steel cables with an accelerating splice, the same is done. Only the punching of the running strand is carried out against the descent under the two root strands of another cable, while clamping one root strand located on the left. So they break through all the strands in order from right to left, clamping one root and passing two others under it.

Fire is a loop made at the end or in the middle of the cable (Fig. 155). A brand is applied to the cable, and its free end is unraveled. Having arranged the loose strands in order, the punching starts from the middle one, passing it under the nearest root strand against the descent. Then they pierce the upper left under the next root, while holding the previous root. The fire is turned 180 ° and the third strand is pierced under the remaining root. In the process of further punching, you need to look so that the root strand is between the two running ones. Then, one strand is punched under one root. A total of three punches are made.

Rice. 154. Splice: A- short splice (1- 4 - successive methods of splicing two cables); b- long splice

To apply a brand (Fig. 156), you need to take a pile or canvas thread, put it in a loop on the cable and wrap it with the free end 10-20 times. Having passed the end into the loop, the latter is dragged and cut off.

Rice. 155. simple fire

Rice. 156. Simple brand: 1 - running end; 2 - root end

4. Making fenders and mops.

Fenders serve to protect the ship's hull from impacts and friction during mooring and when the ship is moored at the berth. You can use hard (wooden) and soft (wicker) fenders (Fig. 157). Soft fenders are made from pieces of old rope, tow and crushed cork. A cork or tow is placed in a canvas bag according to the size of the fender, then the old cable is unraveled and the bag is tied crosswise with it, leaving a loop on top. The bag is suspended at a convenient height and passed through the loop of the cable. The latter are twisted for each other. At the end of the work, the free ends are tucked under the braid. A mop is made as follows: a piece of an unnecessary vegetable cable is loosened into heels, a handle is cut out, as shown in the figure (Fig. 158), the end of the handle is evenly wrapped with heels and a benzel is applied. After that, the cables are turned inside out, fitted and fastened again with a benzel.

The ends of the heels are trimmed evenly, the mop is washed and dried. At the other end of the handle, a hole is drilled for attaching a cable with a loop (the cable is needed so that the mop does not fall overboard).

Rice. 157. Making a soft fender

Rice. 158. Making a mop (successive manufacturing techniques)

For the production of steel cables, the requirements for which are stipulated by GOST 2688-80, a special wire is used, which is preliminarily subjected to heat treatment which gives it high strength. Steel cable is actively used in various industries: oil refining, coal mining, construction, in the operation of sea and river transport, etc.

The purpose of the steel cable

The product is most often used when performing rigging, towing and lifting works. So strong and at the same time flexible element is an integral part of the equipment of cranes, excavators and drilling rigs. In addition, it is used in the mechanisms for lifting and lowering passenger and freight elevators, it is used to reinforce concrete, giving it the required mechanical characteristics. Such cables have received the widest application in the performance of lifting operations, because the high strength and flexibility that these products possess make it possible to manufacture load-gripping devices from them that can withstand significant mechanical loads.

Given the complexity of the work for which they use steel cables should be given very serious attention to their choice. On the modern market there are different kinds ropes and cables made of steel, which makes their choice very difficult for an ignorant person. In such cases, it is better to turn to professionals who are able to select the product in accordance with the tasks for which it is planned to be used.

Strict compliance requirements performance characteristics applied not only to metal cables, but also to additional elements in combination with which they are used. Such products are subjected to special tests and checks before they are put into operation, after which they are issued certificates and permits for use for their intended purpose.

The main parameters by which these cables are selected by the consumer are flexibility, strength and load capacity, as well as the limit values ​​​​of their tension. In order to increase the resistance of steel cables to the effects of aggressive environments in which they will be operated, in some cases they can be subjected to additional processing. The weight of a wire rope can be one of the most significant parameters when it comes to certain areas use of this product.

Rope design features

Steel cables today are manufactured using different technologies, but there are common features their devices, which should be discussed in more detail. The basis of the design of any such cable is a set of steel wires intertwined around a common core. The core can be made of various materials, including non-metallic ones. The main purpose of such an element is the formation of a model finished product and protection of its surface from punching, which can occur under the influence of significant mechanical loads. If metal is used as the core material, then its surface must be protected from corrosion, for which it is coated with zinc or aluminum.

Often the cables are made with a core of organic materials, which are used as cotton fabric, manila, hemp or sisal. Organics are known to be very susceptible to decay and fungal infections. To avoid this phenomenon, organic cores are impregnated with a special lubricant, which significantly extends the service life of the steel product and additionally helps to minimize friction between its constituent elements.

Types of ropes are also actively used, the core of which is made of synthetic materials: polyamide threads. As a rule, such cables have a two-layer device, while both layers, separated by synthetic threads, do not rub against each other. The great advantage of steel products of this design is their relatively low weight - a very important property in many situations. As metal cores of cables, insulated metal plates, wire or tape, twisted in a spiral can be used.

According to the level of their flexibility, steel cables are divided into three categories: with the least degree of flexibility (hemp core and 42 wires), flexible (72 wires, from which individual strands are pre-made) and with increased flexibility (hemp core and 144 wires, pre-made twisted in 6 strands).

Types and marking of products

When choosing a steel cable for solving certain problems, a lot of factors should be taken into account: its structure, length and diameter, as well as the main parameters - flexibility and the maximum load that it can withstand. It is imperative to pay attention to the design of such a product, which largely determines its main characteristics. Cables are classified as one or another type of construction depending on how many twists they are made of. Yes, steel cable. single lay consists of a core on which a wire is wound in a spiral. Such elements are often used as separate strands for the manufacture of more complex products - double lay steel cables.

The design of such products includes a core, on which strands are wound in a certain sequence. Strands are used to make both single-layer and multi-layer cables, which are able to withstand significant loads and may have the ability not to twist during operation, which is very important in many situations. The most complex in their design are triple lay cables, for the manufacture of which so-called strands are used. A strand is, in fact, a double-lay steel cable, specially made in order to further form more complex products from it.

For the production of cables of complex design, strands made in various ways can be used. To mark and determine the type of strands from which the cable is made, use the designation LK - linear touch. The most simple strands (LK-0) are characterized by the same lay pitch in all layers and its repeating pattern.

To form the layers of the strand, wire of different diameters can be used, in such cases it is designated LK-R. There are also mixed types of strands, some layers of which are made of wire of the same diameter, while others are made of wire of different diameters. Such strands are designated LK-RO. The method of making strands is very important to consider when choosing cables. for various purposes, since it is he who largely determines the properties that the finished product has.

For the production of steel cables, strands are also used, made according to the principle of non-linear (LK), but point contact of the wire in them (TK). The peculiarities of the arrangement of such strands are that in each of their layers a different wire winding pitch is used, in addition, these layers intersect with each other. It should be said right away that it is not recommended to use steel cables with such strands in cases where they will experience significant dynamic loads.

This is explained by the fact that due to the low density internal structure such products, their layers under the action of dynamic loads are subjected to strong friction, which can lead to a rapid failure of the entire cable. There are also combined cables, for the manufacture of which strands of LK and TK types are used. They are designated respectively TLC. Each of the above types of steel cables should be selected depending on their purpose, carefully assessing the conditions in which they will be used.

Classification and characteristics of plant cables. on ships and auxiliary courts The Navy uses hemp, manila and sisal cables. Plant cables are more expensive than steel cables and less durable (non-tarred hemp cables are about 6 times weaker than flexible steel cables of the same thickness).

According to the manufacturing method, there are cables of cable work (ordinary) and cables of cable work (lapel).

Cables of cable work (Fig. 4.11, a, b) are made by twisting the fibers into cables (yarn). Several cables twisted in the opposite direction form a strand. Three or four strands twisted in the same direction as the fibers form a rope. 4-strand cables (Fig. 4.11, b) have a central core. It prevents the strands from sinking and is used in cases where special flexibility and untwisting of the cable is required. 4-strand cables are weaker than 3-strand cables of the same thickness by about 20%.

Rope work cables are usually made of right twist (straight descent). Cables of the left twist (reverse descent) are produced only by special order. Cable work cables (Fig. 4.11, b) are obtained by twisting to the left side of three or four cables of cable work of the right twist - strand-ney. The 4-strand cable has a center core for the same purpose as the 4-strand cable.

Rice. 4.11. Vegetable ropes:
a - a three-strand cable of cable work of the right twist (direct descent); b - four-strand cable of the right twist; c - three-strand cable work cable (lapel); 1 - strands; 2 - fibers; 3 - strand; 4 - cables; 5 - core

Depending on the circumference and the method of manufacture, plant cables are called:

Cords - with a circumference from 8.8 to 37.7 mm;
- lines - with a circumference of up to 25 mm cable work and up to 35 mm cable work;
- cables - with a circumference of 25 to 100 mm for cable work and from 35 to 100 mm for cable work;
- pearls - cables of cable work with a circumference of 100 to 150 mm;
- cables - cables of cable work with a circumference of 150 to 350 mm;
- ropes - cables of cable work with a circumference of more than 350 mm.

Plant cables are used almost everywhere where considerable flexibility is required.

Hemp cables are made from hemp (processed hemp fibers). Cables of cable work are white (from non-tarred cables) and resinous. Cable work cables are only resin.

The squash is tarred with hot wood resin. With normal pitching, the weight of the resinous cable increases compared to the non-resined one by up to 18%. Too much resin makes the cable brittle, less flexible and heavier. Unresined cable is more susceptible to moisture and rots faster than resinous cable.

By technical indicators Depending on the grade and quality of raw materials, hemp cables of cable work, both non-resined and resinous, are divided into four groups: special purpose, special, increased and normal. Cable work cables are made only in two groups: elevated and normal.

The most common on ships are 3-strand cables of direct descent cable work, non-resined and resinous for special purposes and special ones.

Non-resined and resinous hemp cables of cable work are produced with a circumference from 30 to 350 mm. Cables with a circumference up to 275 mm are made with a length of 250 ± 10 m, and with a circumference over 275 mm - a length of 200 ± 8 m. Cable work cables are made with a circumference from 150 to 450 mm and a length of one end 100 ± 4 m.

The relative elongation of the cables without breaking the strength of 8-10%. This makes them suitable for jobs with sudden tension changes. Hemp cables are produced according to GOS T 483-55 (Table 4.11-4.13).

T a b l e 4.11

T a b l e 4.12

T a b l e 4.13

Manila cables are made from manila hemp - the fibers of a wild-growing banana - abacus. They are released unresined. The color is golden brown. The cables get wet a little and do not sink in water, under the influence of moisture they do not lose their elasticity and flexibility, they dry quickly and therefore are little susceptible to decay. Their strength is somewhat greater than the strength of hemp unresined cables. Manila cables lengthen without loss of strength by 20-25%.

According to technical indicators, manila cables are divided into elevated and normal ones and are made in 3- and 4-strands with a circumference from 30 to 350 mm. The length of the bay (the whole end) is 250 ± 10 m. They are produced according to GOST 1088-41 (Table 4.14).

T a b l e 4.14

Sisal ropes are made from sisal hemp, fibers from the leaves of the tropical agave plant. Released unresined. The color is light yellow. They differ from manila cables in less elasticity and strength, greater fragility and the ability to absorb moisture. The relative elongation of the cables is about 20%.

According to technical indicators, sisal cables are divided into elevated and normal ones and are made with a circumference from 20 to 350 mm. The length of the bay is 250 ± 10 m. They are produced according to GOST 1088-41 (Table 4.15).

T a b l e 4.15

Lini- twisted products in the form of thin individual strands or cables of cable work. The lines are made from non-resined and resinous cables; the cables in the lines are called threads.

All lines, with the exception of shkimushgar, are made from hemp good quality, sh k and m u sh g a r - from low-grade hemp. Sh k and m u sh k a - a line twisted by hand from any number of threads. Vorsa - a stump of an old cable, loosened into heels. Lines with a thickness of 18, 20, 22, 25 mm, diplotlines and laglins are made at least 200 m long, the rest - at least 100 m. Lines are produced according to G O ST 1091-41 (Table 4. 16).

T a b l e 4.16

Braided linen cords (halyards) are made by interlacing 8 strands, consisting of several linen threads. The thickness of the cords is from 8.8 to 37.7 mm, the length is from 200 to 600 m. Cords, depending on the purpose and type of thread, are divided into especially responsible ones - from sewing threads No. 14, 5/4 and responsible - from sewing threads No. 10 /3. Cords are produced according to OS T N K L P 7628/778 (Table 4.17).

T a b l e 4.17

Measurement of plant cables, their weight, breaking and working strength. The thickness of the plant cable is measured along the circumference in millimeters. In e from 1 line. m of cable W in kg can be selected from GOS T and determined by the formulas: - hemp untarred special purpose and special

- hemp resinous special purpose and special

- Manila

- sisal

where C is the circumference of the cable, see R and breaking strength of the cable R in kgf
where K is the strength factor (Table 4.18);
C - cable circumference, mm.

T a b l e 4.18. N o t e. Large values ​​of the coefficient K correspond to smaller rope circles.

The value of the breaking strength of the cable can be selected from GOST.

P o d b o r t r o s o v for specific type work is carried out according to the formula (4.4). According to the rules of the Maritime Register C C C R, the safety factor n for plant cables is taken in the range of 6-10; for lifting people - 14.

Rules for acceptance of plant cables. Vegetative ropes in factories are rolled into coils and pulled together in four places with bindings. In one bay of a cable with a thickness of 30 to 75 mm, from one to four separate ends of 250 m each can be assembled; cables with a thickness of 90 and 100 mm can have up to two separate ends of 250 m each; cables with a thickness of 115 mm or more are assembled at one end into a bay. Coils of ropes with a thickness of 34) to 50 mm are packed in an investment fabric or matting and sheathed.

Lines with a thickness of 18-25 mm, Lotlin, Diplotlin roll into bays 200 m long and are pulled together in four places with bindings. The remaining lines are collected in skeins 100 m long and tied in two places. The skeins are collected in packs with lines of the same size and names, the pack contains no more than 20 skeins.

The cords are wound into coils with one whole end. Several bundles are packed in a bale, tied up and sheathed with a packing cloth.

A tag with the name and characteristics of the product is attached to each packaged coil of cable, line, halyard and a certificate is given.

Upon acceptance onto the ship, the cable is carefully inspected and the main design data are compared with the tag on the coil and the certificate. The unresined cable should correspond in color to the natural color of the hemp, should not have brown spots, the smell of rot, mold and burning, should be evenly twisted along the entire length. The strands should not have knots, twists; each turn of the strand should stand out clearly. The tar rope should have a smooth surface, a uniform light brown color and a fresh tar smell. The cable should not have scuffs, knots, bulges and stick to hands. A cable that cracks when straightened (a stale cable with fibers burned out from the resin) cannot be accepted on a ship.

After an external examination, 10 measurements of the cable thickness are made in different places. The arithmetic mean of these measurements gives the circumferential thickness of the cable. Rope thickness up to 50 mm in circumference can be measured with a caliper.

Working with plant cables. To unravel the bay of a plant cable, it is placed with an edge on the deck, the strapping is removed, the inner end of the cable is threaded into the middle of the bay and it is unraveled (Fig. 4.12).

Rice. 4.12. Unraveling a bay of plant cable

The cable received on the ship is pulled by hoists or cargo. Before rigging, lotlins, laglins and halyards are soaked in fresh water, untwisted, and then pulled out.

Vegetable cables shrink when wet (shorten by 8-12%), and when dried, they stretch. Therefore, in rain or fog, in order to avoid breaking, the cables under tension are weakened.

The cable, which was in the water, is thoroughly dried by hanging it or stretching it to its full length above the deck. A wet and then frozen cable under tension significantly loses strength (the strength of a wet sisal cable decreases by 10-15%, untarred hemp - by 20-25%) and breaks easily, so it is recommended to use resin cables in the cold season. The cables contaminated with silt are washed in fresh water and dried.

Mats are placed at the points of contact between the cable and metal surfaces.

Cables are afraid of high temperatures, smoke, soot, soot, exposure to oils and acids (this causes the cable to decay); they are not recommended to be stretched near chimneys, kept open under the scorching rays of the sun.

The cables in operation are wound on views or laid in bays (the latter are placed in a net, on banquets or suspended). When winding the cable onto the view, the root end of it is grabbed to the view drum; cable hoses are placed on the view evenly and tightly, for which they are upholstered with a wooden mallet. A view with a cable is installed in a place protected from rain and covered with a cover. The cover is removed in good weather, the cable is ventilated. The cables are laid in coils in a twist, i.e., the direct descent cables are laid clockwise, the reverse descent and cable cables are counterclockwise.

Plant cable storage. Unused cables are stored in coils in dry ventilated storerooms; once every three months, the cables are raised to the upper deck for inspection, drying and ventilation.

It is recommended to fasten the ends of the cables by the butts, eyelets, as well as the connection of two cables with the help of steel thimbles. High-quality mold reduces the strength of the plant cable by 10-15%. Cables of large thickness, having more than two splices, on responsible work cannot be used.

It is impossible to store plant cables in a packaged form, as this does not allow timely notice the beginning of their deterioration and take protective measures. Approximate service life of plant cables for cable work is 3 years, pearls - 2 years, other cables - 1 year.

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