The shafting is one of the most important elements of the propulsion complex. The main purpose of the shafting is to transfer mechanical energy from the main engine to the propulsion unit and transfer the thrust developed by the propulsion unit to the ship's hull.
Intermediate shaft
In accordance with the Rules for the Classification and Construction of Inland Navigation Vessels of the Russian River Register (hereinafter referred to as RSVP), the diameter of the intermediate shaft d etc. must be no less than:
where R m = 570 MPa - temporary resistance of the shaft material (steel 45X),
k = 130 - intermediate shaft with forged flanges;
With EW = 1.05 - gain;
P = 700 kW - design power transmitted by the shaft;
n = 174 min -1 - speed of rotation of the intermediate shaft.
d i - diameter of the axial hole of the shaft.
d r - outer diameter of the shaft.
For further calculations we take the diameter of the intermediate shaft d pr = 170 mm
Thrust shaft
The diameter of the thrust shaft is calculated using the same formula as the diameter of the intermediate shaft. For a thrust shaft in rolling bearings (3.2.2, p. 34) k=142. Thus we get:
For further calculations, d up = 185 mm is assumed.
Propeller shaft
In accordance with the PSVP, the diameter of the propeller shaft is determined by the same formula as the diameter of the intermediate shaft:
where k = 160 is the propeller shaft with a length of more than 4 propeller shaft diameters from the forward end of the propeller hub.
For further calculations, we take the diameter of the propeller shaft d gr = 205 mm.
In accordance with clause 3.5.1. The PSVP cone of the propeller shaft for the propeller should be made with a taper of no more than 1:12.
To protect the shaft from corrosion, bronze lining is selected. In accordance with clause 3.3.3. PSVP thickness of bronze cladding must be at least:
where d gr = 205 mm is the actual diameter of the propeller shaft.
The thickness of the bronze cladding is assumed to be s = 14 mm.
The thickness of the lining between the bearings can be:
S"=0.75. 14=10.5 mm. We accept 11 mm.
The thickness of the connecting flanges of the intermediate and inner ends of the propeller shaft must be no less than the largest of the following values:
0.2. dpr =0.2. 170=34 mm
where: d pr - diameter of the intermediate shaft;
R mv - temporary resistance of the shaft material, MPa;
R mb - temporary resistance of the bolt material, MPa;
i is the number of bolts in the connection;
D - diameter of the center circle of connecting bolts, mm.
I accept d B = 35 mm.
I use 8 bolts with M35 thread for connection.
The taper of the shafts is 1:10, so the shaft connections to the coupling can be made with end nuts.
Shafting elements
Thrust bearing
A thrust bearing with a thrust journal diameter of 400 mm is selected.
Maximum stop P max = 200 kN.
Support bearings
Sliding bearings with a wick-ring lubrication system are used as support bearings. The bearing is selected according to the diameter of the intermediate shaft d = 170 mm in accordance with OST 5.4153-75.
According to PSVP, the maximum distance between adjacent bearings is:
where k 1 = 450 coefficient for plain bearings.
d r = d pr = 170mm - shaft diameter.
Minimum distance between adjacent bearings:
Since the distance from the thrust bearing to the stern bearing does not exceed 6000 mm, we accept for installation one journal bearing in accordance with OST 5.4153-75.
Calculation of the braking device
According to PSVP, each shaft line must have a braking or locking device that prevents rotation of the shafts in the event of failure of the main engine.
The towing speed is assumed to be v = 3 m/s.
When towing a vessel with the main engine turned off, the propeller under the influence of the oncoming flow creates a torque:
where k m = 0.027 is the torque coefficient,
c = 1 t/m 3 - density of water,
D B = 2.408 m - propeller diameter,
w = 0.25 - associated flow coefficient.
Brake diameter based on torque:
where p = 7500 kPa - permissible specific pressure,
f = 0.4 - friction coefficient (steel-ferrado),
k = 0.11 - ratio of yoke width to brake diameter,
b = 100 0 =1.7 rad - brake pad wrap angle.
Since the brake device is installed on the flange connection of the propeller and intermediate shafts, we take the diameter of the brake equal to the diameter of the flange.
D T = D Ф = 0.62 m.
Friction force:
Tightening force (according to Euler's formula):
where b = 1.7 rad is the grip angle of the friction pad.
To compress the pads we use a screw with an M30 thread.
Thread pitch s = 3.5 mm.
The average diameter is taken d av = 0.9d = 0.9 30 = 27 mm.
Helix angle:
Thread friction angle:
where b = 60 0 = 1.05 rad - thread profile angle,
m = 0.25 - friction coefficient
Torque:
Tightening force:
L-lever length, m
P z? 0.735kN for 1 person.
The brake design is shown in Figure 1.
Rice. 1
Checking the shaft line for critical rotation speed
To determine the critical speed of rotation of the propeller shaft during transverse vibrations, the shaft line is conditionally replaced by a two-support beam with one hanging end. The design diagram of the beam is shown in Figure 2.
Rice. 2
l1 = 11.27 m, l2 = 1.38 m.
Propeller weight.
Shaft rowing, represents one or more shafts connected in one line that transmit motion from a steam engine, turbine or other ship engine to the propeller or paddle wheels (see).
The Shaft line of a large warship consists of the following main parts: the crankshaft of the machine or steam turbine spindle, the intermediate Shafts, the thrust Shaft, the stern Shaft and finally the propeller or end Shaft.
Sometimes some of the listed parts (for example, the stern shaft and the end shaft) are connected into one common shaft, and with a short line there are no intermediate shafts.
Each of the parts of the Shaft has a special purpose and each of them has its own requirements.
I. Cranked Shaft forms an integral part of the steam engine, to which the work of the cylinders is transmitted.
In multi-cylinder machines it usually consists of several pieces connected to each other by flange couplings. Each piece of shaft has one, two or three elbows and is forged for navy ships in its entirety.
To lighten the weight, the crankshaft is made hollow; the ratio of the diameter of the internal drilled hole to the diameter of the shaft is usually taken equal to half.
In order to avoid prolonged disablement of the ship in the event of a crankshaft failure, during the construction of the vessel itself, a spare part of this shaft is prepared, and all its parts are designed to be interchangeable whenever possible.
An exception is made for high-power machines, in which shaft failures, manufactured with the modern state of technology, are extremely rare.
The shaft necks rotate in the frame bearings of the machine, gun metal, filled with anti-friction metal, while the neck of the crank is encircled by the bearing of the lower head of the connecting rod of the same design. Bearing all the blows from the inertial forces of the moving masses of the steam engine and constituting the most essential part of the latter, the crankshaft requires the most careful calculation when designing. There are a number of empirical formulas for calculating the crankshaft; These are, for example, the formulas of the English Lloyd's and Bureau Veritas, given in reference books and special technical sources.
In these formulas, the diameter of the shaft is determined depending on the number and size of the machine’s cylinders, the length of the piston stroke, the steam pressure in the boilers and some other data characterizing the power of the machine. Although practical formulas give good results, it is necessary to accurately test the crankshaft for complex torque and bending moments using the theoretical formula:
where: d - shaft diameter in dm., f - permissible stress of the material in English fnl. per sq. ind., T1 - torque and M - bending moment.
All stresses in the material, both for bending and torsion of the shaft, and for crushing and friction work in the bearings, due to the particularly careful manufacturing of all these parts and the desire to lighten the weight of the mechanisms, are taken to be much greater when designing military fleet vehicles than for commercial fleet vessels.
In steam turbines there is no crankshaft - it is replaced, that's how. called turbine rotor spindle.
I. Intermediate Shaft serves to connect the crankshaft of a machine or the spindle of a steam turbine with a thrust or sternshaft. They also avoid making the intermediate shaft long so that they can be removed from the engine room without removing bulky parts of the mechanisms. Therefore, there are often several intermediate shafts; they rest on intermediate bearings, sometimes called “corridor” bearings, due to their location in the corridor of the propeller shaft.
Since the intermediate shaft is not subject to shock and is well supported by intermediate bearings, their diameter is calculated only for torsion and is usually made smaller than other shafts of the same vessel.
Bearings are made like frame bearings for turbine and high-speed installations in general, or simply cast iron, filled with anti-friction metal in their lower half.
A worm wheel of a rotary drive is installed on the intermediate shaft or on the crank flange, which is used to manually rotate the entire shaft line when the machines are idle. The shaft is supposed to be turned daily in the campaign.
The thrust shaft is one of the intermediate shafts, only with a special purpose. It carries several rings that are integral with the shaft body and fit into the corresponding cavities of the thrust bearing.
These rings perceive the persistent pressure of the propeller, which imparts movement to the vessel (see Propeller).
The number of rings is calculated to provide sufficient surface area to absorb thrust pressure without excessively increasing the diameter of the rings.
Necessary requirements:
1) precise fit of the thrust shaft rings to the thrust bearing rings, so that the pressure is perceived by all rings simultaneously and
2) the correct location of the intermediate bearings supporting the shaft in order to avoid its sagging, which disrupts the proper operation of the thrust rings.
The thrust bearings adopted in our fleet are in most cases Modzleya systems with removable horseshoe rings to facilitate their fitting and repair; but in small installations, bearings of the ordinary closed type with cavities for the thrust shaft rings are also used. The disadvantage of the latter is inaccessibility for inspection during operation and difficulty in fitting.
The thrust bearing housing is usually made of cast iron or cast steel.
Horseshoe staples - gunmetal, hollow, cast iron or cast steel; in the last two cases, they are necessarily lined with anti-friction metal; in addition, the rings are always cooled with water. The ship's foundation for the thrust bearing is made, perhaps, rigid and connected properly to the ship's hull. In turbine installations, thrust bearings are located directly next to the turbines and therefore special thrust shafts are not required for them; but to separate the Shaft line from the turbines, a special ring and a bearing are made on one of the intermediate Shafts, which holds the Shaft in the proper position when it rotates freely from the ship’s progress after this Shaft is disconnected from the turbines.
One ring of relatively small diameter turns out to be sufficient in this case due to the fact that the shaft does not transmit any work and only rotates freely.
III. Deadwood Shaft passes through the ship's hull in the so-called. the stern tube (see) and along the entire length of the backout packing of this pipe is lined with gun metal bushings mounted on it in a hot state, in order to avoid rusting, since it has to work with water lubricant; if the stern tube is made with a special injection lubricant, then the shaft is not lined.
The part of the shaft between the linings is covered either with a special rubber compound (Villenius), which protects this part from corrosion, or with copper. When installed on a ship, stern tube shafts are inserted through a stern tube whose opening is too small for the flange to pass through; Therefore, the shaft coupling is made hot or with a special ring on the keys.
A brake is usually attached to the inner end of the stern shaft in case it is necessary to stop the shaft while the ship is moving, for example, to disconnect or communicate the shaft line with the engine.
IV. End Shaft,- the last, aft part of the Shaft line, connected with one flange to the stern shaft; On the other, conical end of this Shaft, a propeller is mounted, strengthened with keys and a nut screwed onto the threaded end of the Shaft.
At the propeller itself, the end shaft is supported by an outer bracket attached to the hull of the ship and equipped, like a stern tube, with a sleeve with backout packing, which is why the part of the shaft entering this sleeve is also lined with gunmetal.
The end shaft, like the crankshaft, is designed for complex torque and bending moments due to the fact that it is usually made of considerable length and, like the outer part, is easily subject to impacts.
In turbine installations, where, due to the large number of revolutions of the propellers, the end shaft is of a relatively small diameter with a significant length, they are also checked by calculation for the possibility of destruction from centrifugal force, at the so-called “critical number of revolutions”.
If the diameter is insufficient, the shaft may sag and break, as a result of the centrifugal force that develops with increasing speed.
Both the end shaft and the stern shaft are currently being made hollow; The shaft holes are sealed tightly with plugs on the threads.
In the production of the entire Vala line, the most serious attention is paid to the quality of steel and their finishing. It is required that the cross-sectional area of the blank be at least 5 times larger than the cross-sectional area of the finished forging. When testing test strips, the steel should give a tensile strength of 27 to 30 tons. per 1 sq. dm. and elongation over 30% by 2 dm. length.
After forging, the shafts are carefully annealed; no defects are allowed in the metal during turning; the diameter of the Shaft along its entire length must be the same, and the drilled hole is completely concentric with the outer circumference of the Shaft. The shaft flanges must be strictly perpendicular to its axis.
When assembling the Shafts on a ship and during their service, the most serious attention is paid to ensuring that the entire line of the Shaft is strictly straight and the Shafts lie tightly on their bearings.
Propeller shaft
shafting element directly connected to the propeller. On large ships, the propeller shaft length is up to 12 m; on small ones it is directly connected to the engine and propeller.
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"Propeller shaft" in books
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From the book Legendary Streets of St. Petersburg author Erofeev Alexey DmitrievichRowing Canal The canal was dug in the 1960s along the bed of the Vinnovka River, which flowed from the Middle Nevka and flowed into the Bolshaya. The river separated Bychiy Island from Krestovsky Island, the origin of its name is unknown. The old mouth of the river is a channel leading to the Bolshaya Nevka to the west
ROWING CHANNEL
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rowing ship
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TSBRowing sport
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From the book General structure of ships author Chaynikov K.N.§ 47. Transfer of engine power to the propeller shaft Transmission mechanisms from the main ship engine to the propeller shaft serve mainly to reduce the number of GSSU revolutions transmitted to the propulsion unit. To obtain the maximum value of propulsive efficiency.
Marine site Russia no September 21, 2016 Created: September 21, 2016 Updated: November 24, 2016 Views: 27123
The purpose of the stern tube device is to provide the necessary waterproofness of the ship's hull, and the propeller shaft - one or two supports, to absorb static loads from the weight of the shaft and propeller and dynamic loads from the operation of the propeller under different immersion conditions.
Stern tube devices of sea vessels are divided into two groups:
with non-metallic and metallic liners.In the first case, backout, textolites, wood-laminated plastic, rubber-metal and rubber-ebonite segments, thermoplastic materials (caprographite, caprolon), etc. are used as antifriction bearing materials.
In an oil-lubricated metal bearing, the support bearing shells are filled with babbitt.
When operating a ship, constant and variable loads arise in the stern tube under the influence of forces and moments transmitted to the propeller shaft from the propeller, which cause stress in the stern tube bearings and pipes. The engine transmits torque to the propeller, which is not constant.
Periodic changes in torque in the engine-shafting-propeller system cause torsional vibrations. When the frequency of the disturbing forces coincides with the frequency of natural torsional vibrations, resonance conditions arise, under which the forces in the parts increase sharply.
Significant forces are also observed in near-resonance zones, when partial coincidence of frequencies occurs. In the range of 0.85-1.05 of the calculated shaft rotation speed, the presence of forbidden resonance zones is not allowed.
During the operation of the propeller, periodic disturbing forces and moments arise on its blades, which are perceived by the stern tube device and transmitted to the ship's hull through its bearings. These forces arise as a result of the change in its thrust and the tangential force of resistance to rotation of each blade during one revolution of the propeller. In this case, conditions may be created under which the frequency of the forces occurring on the propeller coincides with the frequency of the natural bending vibrations of the shaft line, which will lead to resonant vibrations of the propeller shaft and high stresses in its main sections.
The total bending moment consists of the moment from the mass of the screw, the hydrodynamic bending moment and the moment from inertial forces during bending vibrations of the shaft line.
Hydrodynamic imbalance of the propeller occurs due to differences in the pitch of each blade or when the propeller operates partially submerged. During the manufacture of the blades, their pitch differs slightly, but during operation, if individual blades break or deform, the resulting forces can lead to vibration that is dangerous for the stern tube supports. During ballast transitions, due to the difference in thrust, an additional bending moment is created, which leads to significant hydrodynamic imbalance and, as a consequence, increased vibration of the ship's hull.
The load from the mass of the propeller shaft and propeller is perceived by the stern tube bearings, which also perceive the construction static imbalance of the propeller. The maximum part of the load falls on the stern tube bearing and its aft part. During operation, additional loads may occur on the stern tube device when the propellers hit foreign objects.
The stern tube device is the same for all ships, regardless of their size and purpose, and consists of a stern tube, inside of which there are bearings, and a sealing device that prevents the penetration of sea water into the vessel. In Fig. Figure 1 shows the stern tube arrangement of a single-screw vessel with non-metallic bearings, the most widely used in the navy. The bow end of the stern tube 4 with a flange 11 is firmly attached to the afterpeak bulkhead 12, and the aft end is inserted into the stern tube 3, sealed with rubber rings 15 and tightened with a union nut 16 with a special stopper 2. The sealing rubber is installed between the restrictive collar 14 of the stern tube and the stern tube with the bow side and the union nut and the sternpost on the other side to prevent the penetration of sea water into the space between the stern tube and the sternpost.
In the area where the stern tube exits, a stuffing box seal is installed inside the vessel, which includes a packing 9 installed between the shaft and the pipe, and a pressure sleeve 10. The stuffing box is accessible from the engine room or the propeller shaft tunnel. In the middle part, the stern tube is supported by floras 13, which can be welded to the pipe or rest on a movable support, as shown in Fig. 1.
Inside the stern tube there is an aft stern tube bushing 5 and a bow bushing 7 with backout strips or its substitute 6 and 8 assembled in them according to the “barrel” or, less commonly, “dovetail” design. The stern tube bushings are secured to the pipe with locking screws to prevent rotation; the longitudinal displacement of the stern bearing strips is prevented by ring 1.
To ensure reliable lubrication and cooling, the bearings are forcibly pumped with sea water; for this purpose, grooves are provided in the set of bearing strips at their joints for the free passage of water. In the backout set, the lower strips have an end-to-end arrangement of fibers, the upper ones have a longitudinal arrangement (see Fig. 1, section A-A), since the lower ones perceive large specific loads. Brass thrust strips 18 are installed between the lower and upper backout strips, with the help of which they are prevented from turning in the stern tube bushing. To protect the propeller shaft from the corrosive effects of sea water in the area of the stern tube, it has a bronze lining 17 or is protected with a special coating.
Bearings are mounted in the stern tubes - they absorb the forces from the propeller and shafting. For the manufacture of stern tubes, steel is used, less often gray cast iron grade SCh 18-36. They can be manufactured welded or inset. In the first case, the pipe is connected by welding to the stern post, the flanges of the ship's hull frame and the afterpeak bulkhead; in the second, it is inserted into the ship's hull from the stern or bow and secured. Insert pipes are manufactured cast, welded-cast or forged-welded. The connection between the stern tube and the stern post is overwhelmingly cylindrical along its length, and in some cases it is conical. The wall thickness of the stern tube must be at least (0.1-0.15) dr, where dr is the diameter of the propeller shaft along the lining.
In general, the stern stem, stern tube, hull and reinforced stern bulkhead should form a single, well-bonded, rigid structure. The insufficient rigidity of this unit, the lack of a rigid connection between the pipe and the flanges of the set, and the presence of weakened fits in the connections of the stern tube with the stern stem do not ensure reliable and trouble-free operation of the stern tube devices and contribute to increased vibration of the stern part of the vessel.
Sealing glands are an important component in the stern tube device. Experience in operating stern tube devices on large-tonnage vessels shows that the most reliable designs in operation are those that provide not only rigidity of the unit, but also a reliable gland seal that prevents sea water from entering the vessel's hull.
In this case, preference should be given to such stuffing box devices that house both the main and auxiliary stuffing box, making it possible to break it afloat without trimming. The stuffing box device can be installed in the bow of the stern tube, as shown in Fig. 1, or have a remote housing.
Rice. 2. Propeller shaft seals
The remote oil seal of the stern tube (Fig. 2, a) consists of a housing 4, which is attached to the flange of the afterpeak bulkhead using studs 7. Inside the oil seal housing there is a packing 3, which is sealed by a pressure sleeve 6 using nuts 5. The auxiliary oil seal can be sealed with a special brass ring 1, the axial movement of which is ensured by simultaneous rotation of three brass screws 2.
The design of a remote, separately fixed gland is irrational, as it overloads the stern tube device and the gland itself with additional loads due to misalignment of the axial gland packing and the shaft.
The seal design shown in Fig. 1 is widely used on ships. 2, b. A separate stuffing box 5, together with packing 4, is completely recessed into the stern tube 3, thereby increasing the rigidity of the seal and improving the operation of the stuffing box assembly. Uniform compression of the oil seal is carried out by rotating one of the six running gears 1, interconnected by a gear 2.
In the design considered, as in many others, auxiliary seals are not provided and, therefore, the possibility of breaking the seal afloat without trimming the vessel is excluded. In this case, the “Pneumostop” seal (Fig. 3) of the Kyiv-type icebreaker, which is installed in the aft part of the stuffing box, is of interest.
A water distribution ring 2 is inserted into the body 1 of the bow stern tube until it stops, which is sealed with two rubber rings 5 and locked with screws 9. The water distribution ring has a groove to accommodate a rubber ring 3 (pneumatic stop) with a bronze inner ring of stiffness 4.
The pneumatic stop is secured with a cover 8 and bolts 7, after which there is a space for stuffing the oil seal. If it is necessary to stop the access of water into the housing, it is necessary to supply air under pressure through channel 6 in the body of the stern tube bushing inside the shaped rubber ring of the pneumatic stop, which will compress the shaft. During normal operation, the gap between the pneumatic stop and the propeller shaft is within 3-3.5 mm, thereby preventing their contact.
1 - fairing; 2 - propeller blade; 3 - propeller hub; 4 - bracket; 5 - propeller shaft; 6 - stern tube device; 7 - intermediate shaft; 8 - support bearing; 9 - brake; 10 - thrust bearing; 11 - thrust shaft; 12 - main engine shaft.
The main elements of the shafting are:
Propeller shaft;
Intermediate shafts;
Main thrust bearing;
Support bearings;
Stern tube device.
STERN PIPES AND LININGS
Sleeve bearings with water or oil lubrication, installed in the stern tube, are used as stern tube bearings. The stern tube is attached with the bow end to the last afterpeak bulkhead, and the other end to the aft end of the hull, for example, in the mortar hole.
Currently, two structural types of non-metallic bearings with cooling and lubrication by water are widely used in shipbuilding: stacked from individual liners and monolithic in the form of cylindrical bushings.
For the manufacture of bushings for stern tube bearings operating in sea water, corrosion-resistant materials are used: brass LTs40Mts1.5, LTs40MtsZZH, LTs16K4, bronze BrA9Mts2L, BrOYUTS2 and a number of other brasses and bronzes. Backout, textolite, rubber, chipboard, and polyamides are used as antifriction materials for non-metallic bearing shells; for metal bearings - babbitt. The characteristics of non-metallic materials are given in table. 6.2. Backout is the name given to guaiac (iron) wood.
Ship propulsors.
The mover called such a ship's device that, using the work of the engine, creates in the water emphasis– a force capable of moving a ship in a given direction.
Movers are divided into:
Bladed - propellers, winged propellers, paddle wheels;
Water jet.
The propeller (Fig. 7) has from 3 to 6 blades mounted radially on the hub. The surfaces of the blades facing the bow of the vessel are called. sucking, facing aft- pumping. There are different screws right And left rotation. To increase the efficiency of propellers, guide nozzles and propulsive attachments on the rudder are used. Guide nozzles can be fixed or rotary and are used on large and small vessels. The propulsion attachment on the rudder regulates the flow of water behind the hub and increases the efficiency of the propeller, as well as improves the rudder conditions.
Fig.7 Screw
Controllable pitch propeller (CPP) has blades that rotate around their vertical axis. They can be installed at any angle, forming the step required for a given mode of operation of the vessel. The CVS allows not only to use the ship's engine in different operating conditions, but also to keep it in place without turning off the engine.
Rice. 10. Adjustable pitch screw,
/ - slider; 2- connecting rod; 3 - crank disc; 4 - stock; 5-piston! 6- spool regulator; 7 - control drive; 8 - oil pump; 9 - electric motor; 10 - oil tank.
Based on the method of connecting the blades to the hub, propellers are distinguished between solid ones and those with removable blades. Controllable pitch propellers (CPPs) are widely used, in which the pitch of the blades can be changed by turning them while the ship is moving. The number of propeller blades on modern transport ships varies from three to six, rarely more.
The diameter of the propellers of modern large displacement ships reaches 10 m or more.
Wing propeller It is a disk mounted flush with the bottom plating and driven into rotation around a vertical axis by a ship's engine. Along the circumference of the disk, perpendicular to it, there are 4-8 blades immersed in water, each of which rotates along with the disk, as well as around its own axis.
Water jet propulsors
Jet boat "Moray"
The boat is equipped with a single-stage water-jet propulsion system. Its main parts are: a water intake with a protective grille at the inlet and a flange for attaching the propeller to the boat transom; four-bladed rotor having a disk ratio A/Ad = 0.8, diameter 189 and pitch 190 mm; a nozzle with a straightening apparatus built into it; reversible steering device and propeller shaft with bearings and stern tube seal.
1 - propeller shaft; 2 - stern tube bearing housing cover; 3 - oil seal Ø 20X42X11; 4 - M8 nut, 10 pcs.; 5 - washer 8, 10 pcs.; 6 - gasket; 7 - bearing No. 46205; 8 - grease fitting; 9 - oil seal Ø 25X47X11, 2 pcs.; 10 - stern tube bearing housing; 11 - water intake; 12 - inspection hatch body; 13 - wing nut M10, 2 pcs.; 14 - hatch cover; metal, foam plastic, fiberglass; 15 - stator (ring with flange); 16 - bolt M8X70, 6 pcs.; 17 - cotter pin 2.5X45; 18 - fairing nut; 19 - reverse steering device; 20 - rubber-metal bearing; 21 - M4X12 screw; 22 - nut M24X1; 23 - lock washer; 24 - nozzle - straightening apparatus; 25 - rotor; 26 - key B 8X50; steel 2X13; 27 - filler - polystyrene foam; 28 - molding, fiberglass; 29 - M6X12 screw, 8 pcs.; 30 - strip of protective grille 3X18; 31 - strip 4X20X150, 2 pcs.; 32 - fitting - water intake of the engine cooling system; 33 - rotor ventilation fitting; 34.35 - flanges; 36 - hub of the straightening apparatus; 37 - straightening vane; 38 - attachment for reverse steering device; 39 - pin M8X24; 40 - fairing.
Ship devices.
Serve to ensure the necessary operational and navigational qualities of the vessel. The main ship devices that almost all ships are equipped with include: steering, anchor, mooring, fender, boat, cargo, towing, railing, awning and etc.
Steering and thruster devices.
The steering device, which includes a rudder and a rudder drive, is designed to control the vessel.
Steering wheel consists of a feather and a baller. Feather- this is a flat or two-layer streamlined shield with internal reinforcing ribs. Baller- this is the rod with which the rudder blade is turned. There are: ordinary rudders, balanced rudders, semi-balanced rudders.
Fig.12 Electric steering device:
a - location of the steering device.
1 - steering gear; 2 - steering pin; 3 - semi-balanced steering wheel; 4 - rudder stock.
b - sector steering gear with electric drive.
1 - manual steering wheel drive (emergency drive); 2 - tiller; 3 - gearbox;
4 - steering sector; 5 - engine; 6 - spring; 7 - rudder stock;
8 - profile figured steering wheel; 9 - segment of the worm wheel and brake; 10 - worm.
Fig.13 Steering device with hydraulic drive:
a - diagram of the hydraulic drive of the Atlas type steering device with telemotors;
b - piston of the hydraulic steering machine.
1 - connection to the on-board network; 2 - cable connections; 3 - spare canister;
4 - steering pump; 5 - steering column with telemotor sensor; 6 - indicator device;
7 - telemotor receiver; 8 - engine; 9 - hydraulic steering machine;
10 - rudder stock; 11 - steering wheel position indicator sensor.
Rice. 7.14. Steering device diagram
1,2- stock bushings; 3 - compensation ring; 4 - stock thrust bearing; 5 - yoke; b - oiler; 7 - helmport tube; 8 - rubber ring; 9 - seal ra; 10 - sternpost heel; 11 - emphasis; 12 - pin; 13- pin facing; 14 - bronze bushing; 15 - baller; 16 - rudder feather; 17 - steering gear
Steering wheel drive consists of mechanisms and devices designed to shift the rudder on board. These include the steering gear and steering gear. The steering gear is usually placed in a special tiller compartment. Transfer of effort to the steering wheel. Developed in the steering machine, carried out using steering gear. There are tiller, sector and screw drives.
Steering gear control drive(steering gear) serves to transmit commands from the wheelhouse to the steering machine.
Additional controls:
Bow rudder;
Active steering;
Rotary nozzle;
Thruster device.
The steering gear consists of the following main structural units: drive to the stock (tiller, hydraulic cylinders, plungers, sliders); fixed or variable displacement pumps; electric drives of pumps; emergency drive; control system and oil pipeline with hand pump, fittings and tanks.
Rice. 17.1. Drive to the steering gear stock in a four-cylinder
Execution
Cylinders (Fig. 17.2) of small steering machines are made in one piece, and larger sizes (to simplify the production of the workpiece and processing) are welded or assembled from two parts: a cylinder and a bottom.
Rice. 17.2. Cylinder
Rice. 17.3. Plunger
Rice. 17.4. Tiller
The main parts must have high strength, have greater accuracy of relative position, high accuracy and roughness of working surfaces.
Cylinders consisting of two parts are processed in the following order. First, each part is processed separately with an allowance for further machining and the ends for welding. To obtain high accuracy of alignment and parallelism, two pairs of cylinders are bored, checking their installation along the mating surface with the guide beams with an indicator with an accuracy of 0.01 mm. In this case, first the surfaces of the first pair of cylinders are bored, and then, without changing the vertical installation of the spindle, the second pair of cylinders of one steering machine.
Anchor device.
Serves to ensure reliable anchorage at sea, in roadsteads and in other places remote from the shore, by attaching to the ground using an anchor and an anchor chain. It consists of: anchors (Fig. 9), anchor chains (Fig. 9), anchor machines, anchor fairleads and stoppers.
Fig.9 Anchor, anchor chain
Anchors distinguished by deadlifts And auxiliary.
The main parts of any anchor are spindle And horns(paws).
anchor chain serves to attach the anchor to the ship's hull.
Anchor machines To lift the anchor, winches with a horizontal axis of rotation of the drum are used - windlasses- or with a vertical axis of drum rotation - spiers
Rice. 7.13 Anchor device diagram
1 - anchor; 2 - anchor niche; 3 - anchor fairlead pipe; 4 - deck hawse; 5 - anchor chain; b - screw stopper; 7 - windlass; 8 - pipe to chain box; 9 - chain box; 10- chain box sewing; 11 - recoil drive of the main end of the anchor chain; 12 - verb
Anchor mooring spiers There are single-headed and double-headed with a vertical arrangement of the mooring drum and chain sprocket. Double-deck capstans are manufactured in the form of separate units: a head with a stock, a drive with a gearbox and a manual brake drive, from which they are assembled on a stand and on a ship. Single-deck spiers are more compact - they do not have a stock; All components and parts are located in the same plane, which allows them to be manufactured in aggregate form.
Double-deck, single-head, electrically driven anchor-mooring capstan (Fig. 18.1) includes a capstan head consisting of a mooring drum 2, put on the stock on two keys, and a chain sprocket 3,
. 
Rice. 18.1. Anchor-mooring double-deck capstan with electric
drive
.
Stoppers designed for attaching anchor chains and holding the anchor in the fairlead in the stowed position.
Mooring and fender devices.
Mooring device serves to ensure reliable anchorage of the vessel at the pier or near another floating structure (ship, barrel).
Includes:
- bollards - steel or cast iron bollards for fastening mooring lines on a ship;
- fairleads - steel or cast iron castings with an oval hole in the bulwark to direct the mooring line to the mooring bollard;
Winches (Fig. 10) or spiers (Fig. 11) (steam, electric, hydraulic) - are designed to pull the vessel to the pier after securing the moorings to it. There are winches simple And automatic.
To prevent damage to the side when mooring to the berth, especially when mooring ships to each other in the open sea in rough seas, ships are provided with fender device - soft or wooden cushions thrown overboard or permanently fixed on board in places most susceptible to impacts.
Rescue equipment.
Rescue equipment- This is a set of means of rescuing passengers and crew provided on board, including:
§ lifeboat device , designed to rescue people in the event of the loss of a ship, as well as for communication with the shore and other ships. Includes: lifeboats ( Fig.12 ), rafts, capsules, work boats, crew boats, davits;
§ life rafts ;
§ floating devices and life-saving equipment for personal use.
Fig. 12 lifeboats.
Cargo devices.
Designed to perform loading and unloading operations by ship's means. The cargo equipment on dry cargo ships includes booms or cranes, cargo hatch closures and means of intra-hold mechanization.
Rice. 23 Cargo masts: a) – single; b) – L-shaped; c) – U-shaped
Towing devices for tugboats.
Towing device, installed on towing and rescue vessels, is intended for towing non-self-propelled vessels and watercraft, as well as self-propelled vessels that have lost the ability to move under their own power.
Includes:
towing winch,
Hook, or guide block,
towing bar,
towing hawse and tow rope limiters.
Special devices (for example, cargo transfers, fishing, research, etc.).
Armature ship pipelines are used to start and stop the system, isolate its individual sections, regulate the amount and pressure of the working medium, and change the direction of its movement. The fittings are divided into taps, valves, clinkers, latches and flaps.
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