Towing device. Towing and coupling devices. What will we do with the received material
Section 39. TOWING DEVICE
Towing is the transportation on the water surface of non-self-propelled (at this moment) self-propelled floating equipment.
There are three main methods of towing: wake, side-to-side (log) and push. The last type of towing
carried out only by river and lake vessels. Lagging is carried out mainly during in-port operations. At sea, wake towing is used when the towing vessel pulls the towed one.
The towing device is called a towing device.
Figure: 91. Towing hooks:
1 - hook hung directly on the arc; 2 - hook with roller; 3 - vertical stop; 4 - latch; 5-fold part of the hook
On vessels specially designed for towing, the towing device consists of towing winches, towing hooks and bollards, which serve to fasten the towing cables and the cables themselves.
The towing winches are installed on icebreakers and powerful sea tugs. They are steam and electric. The towing rope is attached directly to the winch drum. The winch device allows you to automatically maintain a certain tension on the cable. When jerking, the winch automatically releases the towing rope, and when the tension in the rope looses, pick it up.
Harbor tugs are usually fitted with towing hooks. They are simple (Fig. 91, a), semi-automatic (Fig. 91, b) and automatic (Fig. 91, c).
From a simple hook, the tow rope can only be released if it has some slack. Failure to release the tug under tension can lead to an accident. This disadvantage is eliminated by the use of semi-automatic hooks.
To recoil the towing cable from the semi-automatic hook, fold the vertical stop and hit the tail of the latch with a handbrake or a crowbar. The hinged part of the hook will turn under the tension of the cable, and the tug will slide off it.
Figure: 92. Securing the tug on lighters and barges:
a - on the bitten; b - with the help of mash; 1 - towing rope; 2 - bitng; 3-tug hawse; 4- home brew
To release the cable from the automatic hook, it is enough to pull on the cable guy attached to the top of the vertical arm.
The towing hooks are fixed on a special towing bow, along which they can slide when the vessel turns. In addition, special towing bollards are installed in the bow, and often at the stern.
On non-self-propelled ships - lighters, barges, which are permanent objects of towing, there are special devices that provide a simple and reliable fastening of the towing cable.
In most cases, such vessels are equipped with strong towing bittens near the rods. When installing towing bitts in the center plane of the vessel, the towing cable is attached directly to them (Fig. 92, a).
If two pairs of bitts are installed, then a small wash is attached to them (Fig. 92.6), and a towing cable is already attached to it with a bracket. To eliminate lateral movements of the towing cable and thereby reduce the yaw of the towed object, in the bulwark above the stem there is a special hawse for the towing cable.
Self-propelled sea transport vessels, for which towing operations are of an episodic nature, do not, as a rule, have special towing devices designed for long-term sea towing. Their towing equipment usually consists of several pairs of reinforced bollards and towing ropes, designed according to the Rules of the USSR Register for emergency towing.
In case of short-term towing of transport vessels within port waters (entering a vessel into or leaving a port, draping, etc.), the towing cable is attached directly to the bollards. However, even the reinforced towing bollards of transport vessels do not have sufficient strength to attach towing ropes to them during long sea towing.
In this regard, in order to carry out towing operations by transport vessels, additional towing equipment is installed on them in the form of bitts, towing arms and butts, etc. deckhouses, cargo hatch coamings, etc.).
Fastening the tow rope to the towed vessel. During long-term sea towing of a transport vessel, the towing cable is very often attached to one or two of its anchor chains1. So that all the tension of the towing rope is not transmitted to the windlass, chain stoppers with rope pendants are attached to the anchor chains, with the help of which the load from towing will be partially transferred to the bollards (Fig. 93).
The big advantage of this method is the ability to easily change the length of the tug and its sag by pulling or picking up the anchor chains. At the same time, the sections of the chain passing through the hawses will also change, and the chain will not experience kinks and friction in one place. Besides
moreover, the chains are much less damaged by friction on the haws than cables.
All of the above factors have an extremely large positive value when carrying out long-term towing in difficult towing conditions. At the same time, this method requires large and time-consuming preparatory work: it is necessary first to fill up the anchors on the deck with the help of the bow cargo arrows and unstick them from the anchor chains; quick recoil of the tug is difficult.
Figure: 94. Fastening of the tow rope on the bow of the tug:
1 - towing wash; 2 - towing rope:
3 - guy line; 4 - verb-hack; 5 - bars; 6 - wooden fenders
In this regard, during short-term sea towing, a towing cable is attached using special towing pendants "mustaches" (Fig. 94, a) or a wash wound around the coaming of the bow cargo hold (Fig. 94.6).
In the first case, before attaching the tug, the anchors are preliminarily vented and guides are carried into the haws, with the help of which the towing pendants - "mustaches" are pulled onto the deck. The ends of the pendants on the deck of the vessel are connected with a plant cable benzene. For reliable fastening, 15 to 20 slings are made from a 75 mm cable.
If it is necessary to quickly give the tug under the gasoline, a wooden block must be placed and a sharp ax must be nearby to cut the cable.
It is not recommended to connect the ends of the pendants with rigging or anchor shackles, as the towing rope cannot be released if it is taut. In addition, when the towing cable jerks
the yoke can be deformed, and then it will be very difficult to give the tug.
This method of attaching a towing cable is most often used when escorting transport vessels in tow near an icebreaker. In this case, the pendants are attached to the towing cable using a special Nikolaev block (Fig. 95), which is included in the towing equipment of all icebreakers. In the absence of the specified block, this connection is made using an anchor bracket.
When starting the wash, its ends are led into the haws, located immediately behind the forecastle, they are carried around the hatch coaming and connected with a verb-hook for quick return if necessary.
Sometimes it is preferred to distribute the tug tension and
On the coamings of the hold, and on the bollards located nearby. In that
In the case, the ends of the mash, being carried around the coaming, are attached to the bollards or, before they are carried around the coaming, they are placed on one and a half or two hoops on the bollards.
Fastening the tow rope to the towing vessel. When
When a transport vessel is used as a temporary towing vehicle, the towing rope on it is most often fixed with the help of wash to the coaming of the aft cargo hatch (Fig. 96, a) or to the base of the aft superstructure.
To prevent the cable from fraying at the corners of the coamings, wooden beams are placed under it in these places. For the same purpose, the haws, through which the mash cable passes, are sheathed with wood. The cable itself in this place should be covered with pieces of old canvas. If the wash is based on a steel cable, then in Mectax passing through the hawses it must be periodically lubricated with some kind of shooting gallery or fat. The tow rope is usually connected to the wash with an anchor shackle, since the Nikolaev block is not included in the towing equipment of transport vessels. So that when the tension of the towing cable is weakened, the wash cannot go under the hull, several earrings are wound from the stern to support it.
A guy is attached to the bracket connecting the wash with the towing cable, with the help of which, if necessary, the towing cable can be lifted to the deck.
If towing is carried out with two tugs, they can be attached directly to the hatch coaming without putting in the wash (Fig. 96.6).
When towing light objects, the towing cable can be attached to several pairs of reinforced and reinforced cleats (fig. 97). 
Towing ropes can only be attached to steel (but not cast iron) bollards, the diameter of which allows the tug to be placed on them without excessive kinks. So that the load on all the bollards is evenly distributed, only one eight is placed on the first bollards, and one and a half on the second, and the cable is finally fixed on the third bollards (Fig. 98). With a sufficient diameter of the bollards, the most effective method of fastening the tug will be, in which one log is placed on the aft bollard of the first bollards, two on the bow, and on the second bollards the tug is finally fixed with the help of eights.
If towing is carried out in a long tug, then when it is etched away, under the influence of a large dead weight and the movement of the vessel, it can begin to etch at high speed. Doing so could rupture it or damage the devices to which it is attached.
To regulate the speed of the towing cable etching, it must first be spread across the deck with long sleeves. Attach the inner end of each hose with a stopper to strong parts of the body. Then the stoppers are released alternately as the cable is etched away.
During towing, it is necessary to constantly monitor the condition of the towing cable in the places where it passes through the haws and its fastening. If necessary, weed or pick up the cable to protect it from chafing. In order to avoid pulling out the cable, it is recommended to install a chain stopper in front of the hawse, as shown in fig. 99.
The greatest difficulties arise when it is necessary to select (partial or complete) a towing cable at the stern of a transport vessel. This is due to the fact that very often the thick towing cable does not fit on the warping ropes of the mooring winch; it has to be selected with the help of a special whistle driven through the rosin: a block onto the mooring winch (Fig. 100). If the towing cable is long and the distance from the rosin to the hawse is short, this operation must be repeated several times. Having previously pulled in the towing cable into the stern hawse with the help of a guy, it is taken on a stopper and disconnected from the wash. Then, attaching the whistles to it as close as possible to the hawse, they begin to pull back the latter, and a towing cable is selected on the deck. When the point of attachment of the towing cable approaches the kanifas-block, a stopper is placed on the cable nearby, and the whistlers are again transferred to the hawse, etc.
To facilitate the work with the towing equipment, the ship should have a stock of special clamps for quickly connecting the ends of steel cables, making lights on them, etc. At the points of attachment of the towing cable, it is necessary to have spare brackets, stoppers, grapples, rigging and locksmith tools ready at hand ...
It should be borne in mind that at the moment the ships move away from the place, the towing cable can be pulled with a jerk and burst or vibrate sharply, so you cannot be near it at this time.
On an ordinary transport ship, towing ropes, various towing devices (wash, pendant, clamps, etc.) are included in the ship's emergency stock. All towing equipment must always be in perfect order and safety. The towing ropes should be stored in an easily accessible place where they cannot be damaged.
Staples, stopper turnbuckles, clamps must be widespread and lubricated. It is not allowed to use parts of the towing equipment for any other purpose.
All towing equipment must be periodically inspected, replacing parts in which defects are found. Brackets, hooks, lanyards of stoppers are replaced when cracks are found in them, towing cables - if they have more than 10% of the wires damaged over a length of eight diameters.
Towing device
Along with the carriage of goods on self-propelled ships, a large place in the work of the fleet is taken by tug transportation, which in many cases is more profitable. Towing operations are also often associated with the rearrangement and mooring of self-propelled vessels, their entry into and out of the port, and the relocation of non-self-propelled floating structures. These works are carried out by special vessels - tugs, which, among other devices, must have a device that ensures reliable and convenient towing.
The design of the towing device depends on the towing method. The simplest and at the same time the most common method of towing is towing on a hook. In this case, the vessels are connected with a long flexible cable, which is fed from the stern of the towing vessel to the bow of the towed one. Harbor tows are often lagged when the tug is secured with several mooring ends at the side of the towed vessel. With this method of towing, good controllability is achieved, which is very important in a limited port area. Recently, pushing towing has become widespread on rivers. In this case, the tug is installed in the stern of the towed vessel and a reliable connection is made using cables or a special device.
The main parts of the towing device when towing on a hook are the towing cable and g to (Fig. 92).
Both vegetable and steel cables are used as towing cables. Vegetable is usually used for port towing. For sea towing, a steel flexible cable is used. The disadvantage of a steel cable is its low elasticity. Therefore, sea towing is carried out with a long tug length (400-500 m) or 2-3 anchor chain bows are included in the cable. Due to its long length and considerable weight, the cable sags and softens jerks. Synthetic fiber ropes are very flexible.
The towing rope is attached to a special hook. Towing hooks are simple, semi-automatic and automatic. A simple hook (Fig. 93, a) is inconvenient in that the cable can be returned only if there is slack.
Figure: 92. Towing device: 1- towing rope; 2- soft fender; 3- towing hawse; 4- towing arch; 5- biteng; b- towing winch; 7- towing hook; 8- shoulder strap, 9- towing bow
Figure: 93. Towing hooks: a - simple; b - semi-automatic; в - automatic
But often it is necessary to give up the towing rope under tension at the moment of the jerk, when it is directed at an angle to the center plane and causes a large roll of the tug, which can lead to overturning of the latter. Fast recoil of the tensioned cable is ensured by the use of automatic and semi-automatic hooks (Fig. 93, b, c). Both those and others have a folding part, which is held in working position, resting against a special latch. When the latch slides, the turning part is released, the hook opens, and the tow rope slides off it.
In the semi-automatic hook, the latch is manually shifted using a release cable held on the bridge. The latch of the automatic hook is held against shear by a special spring, adjusted to a certain force. In the case when the tension of the cable exceeds the calculated force, the latch moves and the hook automatically opens.
The hook is fixed on the towing bow located in the horizontal plane. Parallel to the towing bow, a shoulder strap is often installed on which a hook, which has a significant mass, lies. The hook is attached to the towing bow through spring shock absorbers.
The location of the towbar installation has a great influence on the seaworthiness of the tug. Usually it is installed approximately in the middle of the ship's length at a height of 1-1.5 m from the upper deck. This position of the bow provides good turnability of the tug and convenient servicing of the towing area, but if the cable is pulled laterally, it can cause a dangerous list of the vessel. Therefore, in sea towing, in order to avoid side jerks, the towing cable from the hook is passed through the aft towing hawse. If it is not there, then the cable is loosened with guys or a chain stopper is applied to it.
To protect the aft part of the deck from the towing cable, several towing arches are installed. The height of the arches is chosen depending on the position of the towing hook.
Many offshore tugs have an automatic towing winch. In this case, the towing cable is not fixed on the hook, but on the winch drum. The winch has a special device that automatically adjusts the rope tension. In the event of an increase in the pulling force, as well as with various jerks, the winch will release the cable, thereby softening the jerks. When the pulling force decreases, the cable is automatically selected.
The towing device should also include bittens and fenders. Installation along each side of 2-3 bitts or arched bollards ensures reliable fastening of the cables when towing with a log. There are soft fenders on the bow and stern of the tug.
The towing device must always be in good condition. All parts of the towing device should be inspected before each offshore towing. Automatic and semi-automatic hooks require especially careful maintenance. Regular cleaning and lubrication of these hooks will not ensure reliable operation. The rubbing parts of the automatic hooks must be paced periodically. The towing ropes should be lubricated with machine oil at least once a month. During storage, the cables are covered with a canvas cover, removing it in sunny weather for ventilation. So that when towing the cable does not fray in the hawse, it is recommended to crate it in the break points. If there are more than 10% of broken wires in the towing rope over a length equal to its eight diameters, the rope must be replaced.
A towing device is a set of products and mechanisms that provide a vessel with the ability to tow other vessels (or other floating craft) or go in tow itself.
The towing device of transport vessels includes:
Towing cables;
Towing bollards;
Towing haws;
Views and banquets for towing rope storage.
In addition to the above, elements of anchor and mooring devices are used (capstan, anchor chains, bollards, etc.).
The simplest and at the same time the most common method of towing is towing from the hook. In this case, the vessels are connected by a long flexible cable, which is fed from the stern of the towing vessel to the bow of the towed one. Harbor tows are often lagged, when the tug is fixed at the side with several mooring lines. With this method of towing, good handling is achieved, which is very important in the limited port water area.
Forced towing operations to rescue damaged vessels are carried out by transport vessels or rescue tugs. In this case, the captain of the towing vessel decides on the spot all issues of organizing and carrying out towing, and also makes the necessary calculations. Requirements for towing arrangements for vessels are specified in the Rules for the Classification and Construction of Sea-Going Ships, Volume 1, Section 5.
The main parts of the towing device for special vessels - tugs.
Towing device of a vessel - tug:
1 - towing rope; 2 - towing hawse; 3 - soft fender; 4 - towing arch; 5 - bitng; 6 - towing winch; 7 - towing hook; 8 - shoulder straps; 9 - towing bow
The main parts of the towing device when towing from the hook are the tow rope and the hook. Both vegetable and steel cables are used as towing ropes.
Vegetable is usually used for port towing. For sea towing, a steel flexible cable is used. The disadvantage of a steel cable is its low elasticity.
Therefore, sea towing is carried out with a long tug length (400 - 500 m) or two or three anchor chain bows are included in the cable. Due to its long length and considerable weight, the cable sags and softens jerks. Synthetic fiber ropes are very flexible. Therefore, it is advisable to use them for sea towing.
The towing rope is attached to a special hook. The towing hooks are necessary in order to be able to quickly release the towing cable at any time. Towing hooks are simple, semi-automatic, automatic.
A simple hook is inconvenient in that the cable can only be returned if there is slack. But often it is necessary to give up the towing cable under tension at the moment of the jerk, when it is directed at an angle to the center plane and causes a large roll of the tug, which can lead to overturning of the latter.
Fast recoil of the tensioned cable is ensured by the use of automatic and semi-automatic hooks. Both those and others have a folding part, which is held in the working position, resting against a special latch. When the latch slides, the turning part is released, the hook opens and the tow rope slides off it.
In a semi-automatic hook, the latch is manually shifted by means of a release cable held on the bridge. The latch of the automatic hook is held against shear by a special spring, adjusted to a certain force. In the event that the tension of the towing cable exceeds the design force, the latch moves and the hook automatically opens.
a) - simple; b) - semi-automatic; c) - automatic
The hook is fixed on the towing bow located in the horizontal plane. Parallel to the towing bow, a shoulder strap is often installed on which a hook, which has a significant mass, lies. The hook is attached to the towing bow through spring shock absorbers.
The location of the towbar installation has a great influence on the seaworthiness of the tug. Usually it is installed approximately in the middle of the ship's length at a height of 1 - 1.5 m from the upper deck.
This position of the bow provides good turnability of the tug and convenient maintenance of the towing device, but if the cable is pulled laterally, it can cause a dangerous list of the vessel. Therefore, in sea towing, in order to avoid side jerks, the towing cable from the hook is passed through the aft towing hawse. If it is not there, then the cable is loosened with guys or a chain stopper is applied to it.
To protect the aft part of the deck from the towing cable, several towing arches are installed. The height of the arches is chosen depending on the position of the towing hook.
Many offshore tugs have an automatic towing winch. In this case, the towing cable is not fixed on the hook, but on the winch drum. The winch has a special device that automatically adjusts the rope tension.
In the event of an increase in the pulling force, as well as with various jerks, the winch releases a little rope, thereby softening the jerks. When the pulling force decreases, the cable is automatically selected.
Icebreaker towing device: 1 - winch; 2 - Bullivan's stopper; 3 - towing eyelet; 4 - Nikolaev block; 5 - benzel
The towing device should also include bittens and fenders. Biteng is a cast iron or steel pedestal designed for attaching tow ropes. Installation of two or three bitts or strong bollards along each side ensures reliable fastening of the cables when towing with a log.
Soft fenders, located on the bow and stern of the tug, allow to avoid dents in the outer skin of the vessel when the tug approaches the side.
In accordance with the requirements of the International Convention for the Safety of Life at Sea, all ships must have line-throwing devices for transferring a life line from one ship to another, which can also be used when transferring a tow line as a guide.
6.4. Towing deviceThe towing of ships by sea is a special case of maritime practice. As a rule, towing is carried out by transport vessels or powerful rescue tugs. To service a towed object, especially a large-tonnage vessel, when maneuvering in ports and narrows, one or two auxiliary tugs are attached to help the towing vehicle.
A towing device is a set of products and mechanisms that provide a vessel with the ability to tow other vessels (or other floating craft) or go in tow itself.
^ The towing device of transport vessels includes: towing ropes, towing bollards (bitengi), tow haws, views and banquets for towing cables storage. In addition, elements of anchor and mooring devices are used (pins, anchor chains, bollards, etc.).
^ The simplest and at the same time the most common method of towing is towing from the hook. In this case, the vessels are connected by a long flexible cable, which is fed from the stern of the towing vessel to the bow of the towed one. Harbor towing is often done lag, when the tug is fixed at the side with several mooring ends. With this method of towing, good controllability is achieved, which is very important in the limited port water area (Fig. 6.51).
The main parts of the towing device when towing from the hook are the tow rope and the hook. Both vegetable and steel cables are used as towing ropes.
^
The towing rope is attached to a special hook.
Towing hooks
are necessary in order to be able to quickly give up the towing rope at any time. Towing hooks are simple, semi-automatic, automatic. Simple hookinconvenient in that the cable can be returned only if there is slack. But often it is necessary to give up the towing rope under tension at the moment of the jerk, when it is directed at an angle to the center plane and causes a "large roll of the tug, which can lead to overturning of the latter (Fig. 6.52). Fast return of the tensioned cable is ensured by using automatic and semi-automatic hooks.
Figure: 6.51. Towing device for towing vessel: 1 - towing rope; 2 - towing hawse; 3 - soft fender; 4 - towing arch; 5 - biteng; 6 - towing winch; 7 - towing hook; 8 - shoulder straps; 9 - towing bow
The hook is fixed on the towing bow located in the horizontal plane. Parallel to the towing bow, a shoulder strap is often installed on which a hook, which has a significant mass, lies. The hook is attached to the towing bow through spring shock absorbers.
The location of the towbar installation has a great influence on the seaworthiness of the tug. Usually it is installed approximately in the middle of the ship's length at a height of 1 - 1.5 m from the upper deck. This position of the bow provides good turnability of the tug and convenient servicing of the towing device, but if the cable is pulled laterally, it can cause a dangerous list of the vessel. Therefore, in sea towing, in order to avoid side jerks, the towing cable from the hook is passed through the aft towing hawse. If it is not there, then the cable is loosened with guys or a chain stopper is applied to it.
Figure: 6.52. Failuresn th tugabout wka
To protect the aft part of the deck from the towing cable, several towing arches. The height of the arches is chosen depending on the position of the towing hook.
Many sea tugs have an automatic towing winch. In this case, the towing cable is not fixed on the hook, but on the winch drum. The winch has a special device that automatically adjusts the rope tension. In the event of an increase in the pulling force, as well as with various jerks, the winch releases a little rope, thereby softening the jerks. When the pulling force decreases, the cable is automatically selected.
^ The towing device should also include bittens and fenders. Biteng is a cast-iron or steel pedestal designed for attaching towing cables and having a reinforced attachment to the deck. The installation along each side of two or three bitts or strong bollards ensures reliable fastening of the cables when towing with a log. Soft fenders, located on the bow and stern of the tug, allow avoiding dents in the hull of the vessel when the tug approaches the side.
Attachment methods for the towing rope. Forced towing operations to rescue damaged vessels are carried out by transport vessels or rescue tugs. On transport vessels, the towing device is installed in case of emergency towing and therefore it is prohibited to use the towing cable for other purposes.
For sea towing, a steel flexible cable is used. The disadvantage of a steel cable is its low elasticity. Therefore, sea towing is carried out with a long tug length (400 - 500 m) or two or three anchor chain bows are included in the cable. Due to its long length and considerable weight, the cable sags and softens jerks. Synthetic fiber ropes are also highly elastic, so it is advisable to use them for sea towing.
On transport ships, the choice of the method of attaching the towing ropes is determined depending on the size and characteristics of the structure of the vessels, the availability of means for fastening the towing ropes, and in case of forced towing - also on weather conditions. In all cases, a reliable fastening of the cables must be ensured and the possibility of changing the length of the towing cable and its immediate return must be provided.
Rand from. 6.53. TOr heating bat ksirnogo Fig. 6.54. Podkrep lazinessx tov:
cable on bollards 1 - rigging chain; 2 - lanyard; 3 - deck butt
When sea towing over long distances, the method of attaching the towing cable to two or one anchor chains is used (Fig. 6.55).
Figure: 6.55. Fastening the towing rope to the anchor chain: 1 - towing rope; 2 - anchor bracket; 3 - an elongated link; 4 - anchor chain;
5 - connecting the cable to the chain using a bracket (option A or B); 6 - steel cable;
7 - fastening the chain with a lanyard with a bifurcated hook (portable stopper)
^
Fastening the tow rope to the towed vessel.
The easiest way is to attach the towing cable directly to the bollards (fig. 6.53). This method can be used when towing small vessels over a short distance in confined sailing conditions, where you need to frequently select and haul off a tug. But in this case, it is necessary to carefully examine the bollards, and if they are not particularly reliable, then they need to be reinforced (Figure 6.54).
Sometimes it is advisable to fasten the towing cable directly to the anchor (Fig. 6.56). The presence of a heavy anchor significantly improves the operation of the towline as a whole. But in this case, it is necessary to think over the method of connecting with the anchor, since a simple throwing of the cable fire onto the anchor legs does not provide connection reliability due to the possibility of rubbing the cable against the sharp edges of the anchor head.
^
If you cannot use anchor chains, then you have to start a wash.
Braga - a steel cable, which is wound behind rigid hull structures (deckhouses, coamings of cargo hatches) with the distribution of the load to as many points as possible, and without sharp bends of the cable (Fig. 6.57). Wooden beams are attached at the corners under the wash. For the emergency return of the mash, a verb-hack is used.
Figure: 6.56. Options for attaching a towing cable to the anchor: 1 - towing cable; 2 - anchor; 3 - anchor chain; 4 - steel conductor
Figure: 6.57. Securing the tug to the wash on the towed vessel: ^ 1 - conductor; 2 - anchor bracket; 3 - clamps; 4 - home brew; 5 - wooden beams at the corners of the hatch coaming; 6 - lifting bracket; 7 - clamps; 8 - towing rope
Figure: 6.58. Fastening of the tug to the wash enclosed around the hatch coaming: a - general view: 1 - earrings; 2 - home brew; b - connecting device: 1 - towing cable; 2 - verb-hack; 3 - conductor; 4 - home brew; 5, 7 - anchor brackets; 6 - tee
Figure: 6.59. Mounting the wash for the poop of the towing vessel: 1 - towing rope; 2 - anchor bracket; 3 - ends of the mash with lights; 4 - earrings; 5 - wooden fenders; 6 - a conductor with a bracket
Fastening the towing rope to the towing vessel (fig. 6.58, 6.59). At the stern, it should be possible to easily and reliably kickback the towing rope in the event of a forced stop at sea and a dangerous approach to the towed vessel, as well as a sudden threat of collision.
In this way, it is more convenient to fasten the towing rope on equal-deck vessels, passing the wash around the stern hold coaming. The bollard should be covered with such a number of mash slags, which is allowed by its load. The remainder of the pulling force should be transferred to the cargo hatch coamings or other strong structures located on the deck of the ship. The mash rope should be taken of the same strength as the towing one, or it should be made of several slings.
When the vessels reach full towing speed, the towing device should be inspected. A watch shall be installed at the stern of the towing vessel and at the bow of the towed vessel to monitor the operation of the towing device. At the place where kickback of the towing cable is possible, there must be a tool that allows either to cut the towing cable, or to activate the release device.
All ships, when in tow, are prowling. Rudder yaw can only be prevented if the yaw rate allows the helmsman to keep the boat on course.
Icebreaker towing vessels in ice. In severe ice conditions or in case of damage to the escorted vessels, it may be necessary to tow them by an icebreaker (Fig. 6.60).
Figure: 6.60. Bat ksirovka t transportn th ship
Preparation of the conducted vessel for towing is as follows.
Anchors are removed to the deck, which is necessary to thread the icebreaker's towing line through the anchor haws, as well as to avoid breakage of the anchors and damage to the icebreaker side. Vessels navigating in ice conditions must always be ready to anchor on deck.
^ A sufficient number of throwing ends and guide cables with brackets are prepared on the vessel's tank for receiving the tug from the icebreaker.
Prepare in advance everything necessary for the adoption and fastening of the "whiskers" on the deck of the ship, for which steel conductor cables with brackets are introduced through the haws, designed to attach them to the ends of the "whiskers", which will be dragged through the haws to the deck.
It is necessary to provide for a quick recoil of the towing line supplied from the icebreaker. One of the ways of attaching the sling is that the "mustache" lights that go out through the anchor haws onto the deck are tied with a Manila or hemp cable. To return the tug this lash is cut. So that this can be done without the slightest delay, a wooden bar is tightly placed under the lashings. When towing, a sailor on watch, equipped with an ax, must be stationed near the lash.
The towed vessel must sail strictly in the center plane of the icebreaker. On sharp turns in the ice, the icebreaker must slow down to avoid breaking the towing line. When towing vessels of large displacement or long length, the icebreaker is poorly controlled. In these cases, when making turns in a towed vessel, it is necessary to put the rudder in the opposite direction and return to normal control as soon as the icebreaker begins to straighten on the channel or on the course.
Figure: 6.61. Icebreaker towing device: 1 - winch; 2 - Bullivan's stopper; 3 - towing eyelet; 4 - Nikolaev block; 5 - benzel
When towing in heavy ice, do not attach the towing cables to the mooring cleats or windlass, which are not designed for heavy loads and when such a load is applied, they will be cut or turned out (Fig. 6.62).
Figure: 6.62. Fastening the tow rope on the towed vessel: a) - two slings are passed through the haws and connected by means of a log; b) - sling lights are connected with benzene; c) - the sling is passed through the Nikolaev block; d) - Nikolaev block 1 - anchor bracket; 2 - log; 3 - sling branches; 4 - towing rope; 5 - benzel
6.5. Load device
A cargo device is a complex of structures, mechanisms and products intended for cargo operations by a vessel.
Loading device with arrows. The main elements of such a device:
masts or cargo columns that support the arrows (on some ships, the frontal bulkhead of the superstructure may be the support);
cargo booms with rigging and equipment for routing and fastening of rigging;
cargo winches;
cargo spaces (holds and twin decks) with appropriate closure of cargo hatches.
The simplest design is a single mast, which is a large diameter steel pipe. To secure the mast firmly, it is passed through a hole in the upper deck - partners and its lower end- spurs welded to the lower deck planking or second bottom. The place of attachment of the spur of the mast is called steps. In addition to being attached to the hull of the ship, the masts are unattached using a standing rigging made of a rigid steel cable. The cables running from the mast to the sides are called guys. Front mast supportedstays, and go to the stern backstays.
To ensure the required departure of cargo arrows overboard, instead of single masts, cargo columns and portal masts are installed, consisting of two masts - L-shaped or U-shaped, which are connected in the upper part saling. The sling serves to fasten the cable that supports the boom (fig. 6.63). A topm is installed in the middle of the saling. The top end of the topmast ends with a flat disc - clotick.
The towing device installed on tugs and rescue vessels is designed for towing non-self-propelled vessels and floating crafts, as well as self-propelled vessels that have lost the ability to move under their own power.
The choice of the type of towing device depends on the purpose of the tug and the towing method. For sea towing on a long cable, the wake method is used; towing in the port and in the roadstead is more often performed log (side to side), as well as in the wake on a short cable (up to 100 m long); for towing on inland waterways, both the first two methods are characteristic, and the method of pushing, which spread in the post-war years after the creation of special river and lake pushers. Towing in ice is carried out in a special way: the bow of the towed vessel is inserted into the recess in the stern of the tug, securely moored and in this position the vessel is towed.
The towing device includes a towing winch (installed only on sea tugs and inland water tugs), a cable, a hook, or a guide block, a towing bow, arches, a towing hawse and towline stops.
The towing winch is designed to adjust the length and tension of the towing cable during towing. The length is usually changed only when towing vessels on inland waterways; in the conditions of a winding fairway, when passing bypasses, rifts and other places, when it is necessary to reduce the distance between the tug and the vessel. The tension of the cable should only be adjusted when towing at sea in rough conditions, when the cable is alternately loose and over-tensioned.
The towing winch has a drum that allows receiving up to 300 m of rope on river vessels and up to 900 m on sea vessels. There are single-acting towing winches - on inland tugs - and automatic - on sea tugs (Fig. 7.40). When towing river and lake vessels, the cable from the towed vessel is directed to the drum of a single-action winch, braked by a band brake (in case of unexpected jerks, the shock absorber as part of the band brake is activated and the winch drum rotates). The design of the winch allows you to release the towing cable while the vessel is under way and to lock the winch drum when the drive is inoperative using the brake.
The repeated jerks arising on the rough sea are softened by a special automatic tracking device that releases the cable when it is over-tensioned and selects it when a slack appears. In order to avoid tangling of the cable on the towing winches, it is imperative that a cable layer is provided.
The towing winches are electrically or, more rarely, steam driven with a pulling force of 6 to 100 tf. Electric winches or view winches are used to feed and haul out towing ropes and perform mooring operations on tugboats that do not have special winches.
Towing cables used for towing are steel, vegetable (hemp, manila, sisal) and synthetic fibers (nylon, nylon, curalon). The latter have advantages over steel and vegetable ropes: they are lighter, more elastic, however, due to the sparking when they break, it is generally not allowed to use artificial fiber ropes when towing ships carrying first-class oil products.
The towing hook is used to secure the towing rope and its recoil when towing without the help of a special winch. On tugboats with towing winches, the hook is a backup. Towing hooks are folding and non-folding, open and closed, with or without a shock absorber, with a mechanical or hydraulic shutter, with automatic, remote or manual recoil. The rules of the USSR Register require that on sea tugs, folding closed hooks with shock absorbers, having a reliable and fast-acting recoil system, are used, which is very important for the safety of the tug - when it reaches a dangerous heel, the cable must be immediately released.
The towing hooks are equipped with spring shock absorbers designed to absorb the energy of the shock waves generated in the cable during towing. On some tugs of a limited navigation area, a tug guide block is used, through which a cable is passed from the winch to the towed vessel. The guide block is attached similarly to the towing hook - on the towing bow or (on inland waterway tugs) permanently.
The towing bow is installed in the area of \u200b\u200bthe ship's CG in length and as low as possible. It is designed to attach the towing hook to the tug hull so that it can move in a horizontal plane (for harbor tugs at least 180 °).
Tow arches made of pipes or round forged steel are located in the stern of the tug (two or three arches) to protect the equipment installed on the deck and people on it from damage by the cable. In addition, the towing arches allow for a smooth transition of the towing cable from side to side.
The stern towing hawse is designed to restrict the movement of the towing cable in the horizontal and vertical planes. The hawses are deaf, with a reclining outline, and also with rollers. Due to the fact that it is difficult to get a towing cable into blind haws, they are used only on small port and roadstead tugs. More common haws with basting, and on large tugs - with rollers.
The side stops of the towing cable prevent it from skidding in the horizontal plane into the nose at an angle greater than the permissible angle of horizontal movement of the towing hook.
The above details of the towing device are used when towing vessels by the wake method. For towing with a log, mooring bollards and spiers are used.
Pushers intended for pushing, as well as pushed vessels or barges, are equipped with coupling devices that ensure a rigid coupling of the pushed convoy (pusher - barge), elasticity upon impact and, if necessary, quick recoil. There are many different types of coupling devices, but the most widespread is a two-bearing coupling made of two vertical welded steel box-section beams and a whole system of cables, as well as double-bearing coupling devices with an automatic coupling lock, which provides automatic coupling of the pusher to the barge and remotely controlled uncoupling within 20 - 30 p.