ZEMSNARYAD - a dredger is a floating machine equipped with mechanisms, aggregates and devices for underwater excavation of soil, mining, transporting it to the required distance with subsequent laying. With the help of a dredger, you can fulfill your desires in a variety of areas: clean water bodies, from a park pond or a sump of a plant, to deepening a river, a lake, extract sand and gravel from a quarry, sapropel from a lake.
The suction dredger is a powerful pump, mostly mounted on floating pontoons, and is often referred to as a dredger. The variety of types of work performed and areas of application gives rise to a variety of models of dredgers, depending on: the specific conditions in which the dredger is operated, the composition of the soil, the depth of development, the distance of transportation and the height of the soil, the availability of roads to the place of delivery of the dredger and the availability of electricity, autonomy in terms of fuel and lubricants, availability of service vessels, climatic conditions and many other conditions. The productivity of dredgers is very different - from 10 m3/h to 200 m3/h on the ground, the depth of development is from 0.5 to 12..15 m from the water surface. The on-board equipment is modern - from power units to instrumentation. The crew is no more than two people, and all units of the dredger are controlled from a warm and comfortable cabin with the help of "joysticks" and buttons.
Choosing a dredger
What is a dredger for? You have become the owner of a reservoir for the first time. It can be a pond or lake, a flooded quarry. Everything was issued: proper permits from local authorities, supervisory authorities. We firmly decided what benefit you want to take from this reservoir: either just clean it from silt and deepen the bottom, or get alluvial sand, or other minerals such as: peat, sapropel...
Or maybe the reservoir has long been owned by your company, in particular, the sump - sludge or ash accumulator, and now there is a need to clean it.
The second step is the acquisition of special equipment for the development of soil under water. The most acceptable equipment for the development of soil under water today are dredgers. Professionals who have been involved in hydromechanization for many years will choose the right model very quickly. Although experts make mistakes.
Nuances when choosing a dredger
Now about transportation, loading and unloading operations, launching. The smaller the weight and size characteristics of the dredger (especially with sufficient strength of its nodes), the cheaper and more accessible the transporting and crane equipment, the easier it is to launch the dredger into the water. Dismantling should be for a minimum number of blocks, preferably without dismantling the cabin, units.
The dredger is a machine used for the construction of harbors and canals, land reclamation, in mining projects, as well as in transport construction (including road construction).
Depending on the purpose, different models of dredgers may differ in some way from each other, but in general, the following list of components and assemblies can be distinguished, typical for this type of machine:
- Frame.
- Papillon piles and pile apparatus.
- Deck superstructure.
- Hydrotransport plant.
It is made in the form of pontoons. It serves as the basis for placing all the necessary working mechanisms.
Located at the back of the case. Provide movement of the dredger in the course of excavation.
Located on the central pontoon. Includes control cabin with all the necessary set of control and measuring equipment.
Placed in the hold of the car. Consists of the following elements:
- soil pump;
- power plant (drive);
- suction slurry pipeline;
- pressure slurry pipeline.
As a power plant can be used:
- electric motor;
- diesel-electric installation;
- diesel engine.
The suction slurry pipeline is a pipe connecting the soil pump and the soil intake device.
The soil pumped out by the pump is fed into the pressure slurry pipeline, through which it is transported to the floating slurry pipeline, and then to the onshore one.
The working body of the dredger, with the help of which the soil is being developed.
Using the boom, the operator adjusts the depth of development, and also moves the ripper. The lifting and lowering of the boom is carried out with the help of a winch, for which a steel cable is fixed on its head.
Performs an auxiliary function of flushing, cooling and compacting the soil pump parts.
Before you start placing an order for a dredger, it would not be superfluous to find out what it is like today, what it consists of, and so on, read about it in our article.
In the event that buying a dredger is too expensive, a good option is to rent it. How this is done and what is needed for this - read, the latest and most relevant information.
Dredge production ^
The production of a dredger is a complex of works in which the direct manufacture of the machine is only the final stage.
First of all, the customer fills out a questionnaire and draws up a technical assignment, in which he describes in as much detail as possible the requirements for the future machine, as well as all the features of the planned dredging or alluvial works.
The design department of the manufacturer studies the terms of reference and the questionnaire, and also analyzes information about the type of soil being developed, current and waves in the operating area of the designed dredger, climatic conditions, navigation, distance to unloading the soil.
In addition, the possibility of transport delivery of dredger modules to the place of work is taken into account.
The information obtained serves as the basis for the development of a dredger project, in which, first of all, the type of the future machine is determined and justified. Depending on the task and working conditions, this can be:
- dredger with rotary cultivator: provides high-quality loosening of the soil, but cannot be used on hard rocks.
- dredger with milling ripper: able to work with almost any type of soil. Provides a fairly even bottom profile. Flaw: May interfere with navigation.
- dredge with free suction: instead of a baking powder, hydraulic erosion of the soil is used, which is then sucked up by the soil pump into the slurry pipeline. The best option for the development of loose soils.
- dredge on caterpillar tracks: Suitable for all types of ground, except for hard rocks or soils containing large stones. If the waves and current are below the pontoons, they have little effect on the operation of this machine. It has extremely high mobility and stability.
- multi-bucket Dredger: The use of this type of dredger is driven by the need to keep the excavated rock relatively dry. Requires a barge or floating conveyor belt to unload soil. Nowadays, it is most often used for the extraction of minerals: gold, diamonds, tin, etc.
- grapple or multi-grab dredger: The performance of these dredgers depends on the cycle time and bucket volume. Advantages: allows you to develop at great depths and extract large stones, easy to operate, has a relatively low cost.
- Backhoe dredger: Great for hard soil excavation. At the same time, it allows you to quite accurately plan the profile of the bottom.
When developing a project, engineers determine the required dimensions of the working bodies and other components of the dredger, select the type and power of the drive, calculate the required load capacity of the winch, etc.
At the place of production of the dredger, only a partial assembly of the individual components of the machine takes place in such a way that it is transportable.
This point is very important, as more and more projects are being carried out in remote areas with undeveloped shipping. The dredger can only be delivered to such regions by car or rail. That is why it is so important at the design stage of the machine to provide for the possibility of its delivery by these modes of transport.
An example of such mobility is the BEAVER dredgers from IHC, individual blocks of which are adapted to international container standards.
The final assembly of the dredger and launching are carried out at the work site.
How to determine the quality of a dredger ^
Before signing a contract for the supply of a dredger, experts recommend visiting the manufacturing facilities of the manufacturer.
This visit will give you the opportunity to personally verify the quality of the assembly work, to check how well and with what equipment the welds are performed.
A sign of a solid, reliable and durable design is the presence on the body of the machine of the so-called ship set. It is a strong skeleton of rolled metal beams of angle, tee or strip profile.
Ensure that the foundations under machinery and equipment are secure.
If they are not strong enough, under the influence of engine vibration, the entire structure will quickly become loose and you will have to spend a lot of time and effort welding and patching numerous cracks.
It is desirable that the design of the dredger provides for disassembly into a minimum number of modules that can be conveniently transported.
Do not forget that for proper operation, as well as the possibility of repair, the dredger must be accompanied by comprehensive operational documentation:
- passport (form);
- specification;
- technical description;
- user manual.
If you do not need a "large" dredger, then you may be interested in a mini-dredger. About these units, different companies and names, for example, Minnow, Crab and others, make the right choice.
The composition of the dredgers operating on the inland waterways of Russia is determined by the properties of the developed soils, the conditions for their extraction and removal, hydrological and other factors of the work sites.
Depending on the listed and other factors, dredgers are divided into types according to the following criteria:
The method of separating and lifting the soil from the bottom of the reservoir and its removal outside the developed slot;
Mode of working movements of dredgers in the process of extraction and removal of soil;
Type of power plant;
The method of moving the dredger from one job to another;
Hull structures.
Separate types of dredgers are distinguished by their hourly productivity, expressed in cubic meters of excavated soil.
According to the method of separating the soil from the bottom and raising it above the surface of the water, dredgers and scoop shells are distinguished.
Dredgers (Fig. 1, a) suck the soil together with water by a soil pump with a suction pipe submerged below the bottom surface. Water entering the pipe erodes and captures the soil. The mixture of water and soil is called pulp. The latter, through the suction pipe, enters the soil pump, and then into the pressure pipeline of the dredger housing attached to the pump, to which a floating pipeline is connected, intended to move the soil to the place of its laying. The process of moving the pulp along the pipeline is called refilling. All types of soil can be refilled, but gravel and stony soils are mostly impractical to move in this way due to the fact that the soil pump and the soil pipeline are very worn out.
Ground pipelines are floating and coastal, i.e. refilled soil can be transported both to the water and to the shore. There are dredgers in which the soil pipeline, suspended on a special boom, goes away from the projectile. On low-capacity dredgers, the pulp can move away from the projectile in the form of a jet (Fig. 1, b) ejected through a special nozzle.
For the development of cohesive clay soils, dredgers with a mechanical baking powder, which is a cutter with knives, are used (Fig. 1, V), which separate the soil from the bottom of the reservoir in the form of shavings. The end of the suction pipe enters inside the cutter so that the soil chips are carried away by the suction water jet into the suction pipe.
To improve the absorption of sandy and gravel soils, hydraulic looseners are used, which are devices that eject one or more jets of water under pressure, loosening the soil. This increases the productivity of the dredgers and improves the cleanliness of the working - it reduces the unevenness of the bottom formed after the operation of the dredger.
Bucket shells are multi-bucket and single-bucket. The latter are divided into rod and clamshell. For multi-bucket shells (Fig. 1, d), the main working device is an endless bucket chain moving along the bucket frame.
The scoops are emptied over a soil well, from which the soil enters special vessels - scows, adapted for quick release from the soil. In scows, soil can be transported to any distance. In cases where the emptying of scows into the water is unacceptable due to the conditions of navigation or when the soil must be unloaded ashore, scow unloaders are used. The latter have devices for extracting soil from the scows and transporting it to the shore.
The soil extracted by multi-scoop projectiles can also be removed through a floating soil pipeline, but for this it is necessary to have a soil pump with an engine on the projectile. Such shells are not built in the USSR; more economical dredgers with mechanical baking powder are used instead.
Rice. 1. Main types of dredgers:
A- dredger; b- dredging pump with jet ejection; c - dredger with a mechanical baking powder; g - multi-bucket projectile; d - rod projectile; e - clamshell projectile
Multi-bucket projectiles of small productivity can remove soil away from the projectile along a long inclined tray, called a longcouloir.
There are multi-bucket projectiles of low productivity (for small rivers), which remove soil away from the projectile along a conveyor, which is a rubberized tape (chevron - with ribs) moving along rollers. The conveyor can move soils (except for highly liquefied ones) not only in a horizontal direction, but also with some elevation.
On a rod projectile (Fig. 1, d) the scoop is attached to a rod, at one end hinged on a special boom. The other end of the bar is held by a cable. The scoop is lowered to the required depth. When choosing a cable, the scoop captures the soil. After the scoop is filled with soil, it is raised, the boom is turned and the scoop is emptied above the scow or at some distance from the projectile.
On a clamshell projectile (Fig. 1, e), the extraction of soil is carried out with a bucket consisting of two or more valves. The bucket is suspended on a cable to the boom. To extract the soil, a bucket with open doors is lowered to the bottom (given away). When the bucket is raised, the flaps automatically close, capturing the soil. The bucket is emptied above the scow or at some distance from the projectile (for example, on the shore).
The dredging devices of the dredger are small in size, therefore, during dredging operations, the shells are moved across or along the slots (deep areas). When the projectile is moved transversely with respect to the longitudinal axis of the developed slot, called papillonage, narrow chips of the soil are removed across the entire width of the slot. With longitudinal movement, the slot is developed in the form of a trench; trench development of slots is possible on sandy soils. Trenching is based on the fact that when the suction device is immersed by a certain amount in sandy soil, a funnel is obtained; when moving the dredger along the slot at the bottom, a trench is formed. To deepen the slot across the entire width, a series of parallel trenches is developed.
The dredgers without mechanical openers work in a trench way. Dredgers with baking powder and dredgers equipped with special tips work with papillonage. In accordance with the above, depending on the method of working movements, papillon and trench dredgers are distinguished.
According to the type of power plant that drives devices for extracting and moving soil, dredgers are: with internal combustion engines - diesel, diesel-electric, on which internal combustion engines drive electric generators that generate electricity to drive the electric motors of individual units of shells, steam-electric, where electric generators are driven by steam engines.
Modern dredgers are built with diesel and diesel-electric power plants and electrified mechanisms. The cost and maintenance of such projectiles is lower than with steam power plants, which must have steam boilers, large coal bunkers or oil tanks. This increases the size of the shell bodies, requires more maintenance personnel and increases the cost of excavation by 25-30%. However, in the dredging fleet there are still steam shells built in previous years.
According to the method of movement of dredgers from one job to another, self-propelled and non-self-propelled shells are distinguished.
Self-propelled dredgers have propellers (mainly screws) driven by power plants designed to extract soil, or independent. The latter are on electrified dredgers, where the main engine drives a generator that generates electrical energy, and electric motors are installed to operate individual mechanisms. The power of the dredger propellers must be sufficient to move it and the service vessels available with it. Non-self-propelled dredgers are moved from one job to another by towing motor ships.
The strength of the hulls depends on the area of operation of the dredgers. On this basis, they can be river, lake and sea. To work on large reservoirs, dredgers with lake-type bodies are built.
The main production indicator of a dredging projectile is its technical performance, given by the projectile in optimal soil and other conditions. Each type of dredger has its own most favorable conditions. For example, dredgers without baking powder give the highest performance on medium-sized sands; multi-bucket shells - on silty and sandy-gravelly soils of medium density, filling the scoops completely and well falling out of them; single-bucket rod shells - on coarse gravel. In addition to the physical properties of the soil, the thickness of the removed layer and the depth of soil extraction affect the technical performance. The highest productivity can be achieved starting from the layer determined for each dredger and the estimated depth of soil extraction. On dredgers, the technical performance corresponds to certain values of the length of the soil pipeline and the height of the refilling of the soil.
The technical performance is established in the process of spinning production and heat engineering tests. It is determined by the volume of the recess (developed slot). To do this, calculate the volume of excavated soil and divide it by the number of hours of clean (minus all downtime) work of the dredger.
If there are several soil intake or soil removal devices, the technical performance is determined for each device: for dredging pumps - with trench and papillon tips, for working with baking powder and without baking powder; for multi-bucket shells - when working on scows and longcouloir, etc.
Estimated is the performance assigned to the dredger for specific conditions for the extraction and removal of certain soil; actual - the performance that the dredger gives in the process of performing this work.
The ratio of actual productivity to technical productivity is called the utilization factor of technical productivity. For example, if the actual productivity is 400, and the technical one is 500 m3/h, then this coefficient is KP = 0.80.
The coefficient of use of working time KV is the ratio of the number of hours spent on the extraction of soil to the time spent by the dredger at work or on the reach. For example, if with a working period of 3600 hours, 3000 hours were spent on soil extraction, then KV = 0.83.
The product of the considered coefficients is called the exploitation coefficient
If you want to know how rivers deepen or beaches form, we recommend this article for reading. In it you will learn what a dredger is and how it works.
Suction projectile is an earth-moving transport unit with a continuous work action. These devices are intended for sand extraction, delivery of pulp to the place of discharge, underwater mining of rocks and clearing the bottom of rivers.
The following models of dredgers are considered the most common: 300-40, 350-50L 500-60, 1000-80 and 1500-100. Let's take a closer look at the main components of the unit using an example suction dredger 1000-80. This unit is characterized by high performance and power. The main part of the dredger is the drive system, which consists of a 3MP-125 gear motor. Thanks to these mechanisms, the rotation speed varies from 12 to 18 rpm.
The body of the projectile has a rectangular shape and is divided by partitions into 10 compartments. Part of the compartments is used as a living room. A cutout 4.5 m wide and 12.0 m long is made in the front of the body, which is designed for hanging the frame of the soil intake device. The engine room is located in the middle of the hull. There is a water supply pump and a starting system. Dredger 1000-80 is not self-propelled. To make it easier to tow, the bottom of the hull is raised to the waterline. The superstructure consists of a metal frame, which is sheathed with wooden shields. A hatch is provided above the control compartment. Through it, you can lift heavy equipment with a crane. The dredger also has a rheostat for regulating the operation of the electric motor at 240, 260, 280 and 297 rpm. Thus, the start of the soil pump is facilitated. For additional water supply, two more pumps can be installed.
The soil sampling unit is located on a welded frame. The winch for lifting the frame is located in the forward section of the frame. The suction pipe is suspended from the transverse diaphragms of the frame. The upper part of the tube is connected using a stuffing box compensator and a flexible rubber hose. To loosen the soil, a cutter is used, which consists of six helical knives.
In the engine room, a manual overhead crane is provided, designed to lift 10 tons. Also, to lift parts, two monorails with rolling cats weighing 5 tons each are attached to the A-shaped boom. To lift the cargo on board, two jib cranes with manual hoists were provided.
The process of soil extraction is as follows: water is poured into the soil pump and the main engine is started along with the gearbox. With the help of a frame-lifting mechanism, the suction pipe is buried in the ground. Further, when all the main units are put into action, a vacuum is created in the suction pipe. Then, the water flowing to the soil receiver captures the particles of earthen rock. Thus, the slurry moves along the soil pipeline to the pump. Then the mixture falls on the blades of the impeller and is ejected to the body section of the pressure pipeline.
The purpose of the working equipment of the dredger is the destruction of soil
that, removing it from the face and forming a trench. There are following
blowing methods of soil destruction and transportation: hydraulic
skie, mechanical, combined. The most effective is
the use of combined methods, for example, mechanical destruction
soil removal and its hydraulic transportation from the slaughter zone.
Dredger (dredging projectile)- floating means for sub-
water development of soils and mining of non-metallic materials (sand, granular
wiya) from the bottom of reservoirs. The dredge is equipped with means for workers
movements, transportation of slurry (pulp) through the slurry pipeline
ladies to the place of laying.
Dredgers are divided into the following types:
According to the working body - for suction, ejector, screw, er-
By working movements - anchor-cable, pile-cable,
pile and with the help of engines;
According to the type of soil ripper on suction dredgers, ejector and airlift-
nyh - milling, hydraulic or milling-hydraulic
(rarely used augers, vibration and other rippers
According to the method of transporting the soil - in its own hold
(hold dredger), through floating and onshore slurry pipelines,
along the suspended slurry pipeline, along the long couloir (long flume), in
scows, in bunker barges;
According to the type of drive of the working body - diesel, diesel-electric,
electric diesel-hydraulic, diesel-electro-hydraulic
personal.
Scope of dredgers:
Dredging;
Alluvium of dams, dikes and beaches;
Extraction of building materials and minerals;
Development of ash and slag storage facilities for thermal power plants;
Cleaning of canals, rivers and various reservoirs, industrial and
agricultural sedimentation tanks;
development of underwater trenches for laying pipelines (du-
kerov) and cables, as well as their washing;
Alluvium of roads and areas for industrial and civil construction
authority.
question number 20 option 4
1. As traction means for pulling underwater pipes
pipeline, depending on the required traction force, it is recommended
it is possible to use special traction winches of the LP series (winch pro-
hauling), tractors equipped with winches, as well as the same type
coupled tractors.
Tractors should be used in the construction of small
transitions and traction forces up to 20–30 tons.
If tractors cannot move in the crossing range, then it is allowed
repents of their movement along the shore with fixation on the shore of the block
to change the direction of the traction cable.
2. When pulling the pipeline, if the power of traction
funds are insufficient, pipelayers can be used to lift
ma separate sections of the pipeline located on the coast. For workers
pipelines with a diameter of less than 1020 mm cannot be applied to the pipeline
water additional pushing forces, with a diameter of 1020 mm and more
- the magnitude of the pushing forces and the need for their application should
be substantiated by calculation in the design of work.
question number 20 option 5
The working bodies of underwater earth-moving machines are mechanisms operating in an aggressive environment (water, soil, solid inclusions) with large dynamic loads. The requirements for working bodies must satisfy the conditions for normal operation of machines.
Mechanical rippers are divided into the following groups: milling, rotary, rotary bucket, screw, vibration, etc.
Rotary rippers are used to destroy overgrown vegetable soils (Fig. 87). Working bodies consist of drums with knives. Drums are disks on which knives are fixed.
Milling-hydraulic rippers are used to prevent sticking of cutters and increase the suction area. On the cutter of such a ripper, hydraulic nozzles of the side, frontal and flushing types are installed (Fig. 88).
Rotary bucket rippers are available with one or two rotors, with a hopper or a rotating suction pipe, reversible.
Screw rippers are used for the development of peatlands and are replaceable equipment.
Silty and gravel-song soils are developed by vibrating soil intake devices. Vibration drives are hydraulic and electric vibrators.’
question number 21 option 1
Rope-scraper installations can be used to develop
tops of trenches in swamps, construction of crossings through small
rivers and reservoirs, as well as in mountainous areas on slopes of more than 20 °
Scheme of operation of the rope-scraper installation:
a - with one bucket; b - with two buckets
Scheme of work of LS-302 and LS-1001
The installation consists of a tractor (T-100 tractor), a two-drum
buggy (L 51), mounted on the rear axle and towing device
tractor, a set of scraper buckets and an anchor device with
block. Hook hooks can be used as such a device.
anchor attached to the installation, buried in the ground or laid in
perek trench logs or pipes, as well as a tractor
question number 21 option 2
Currently, the following methods for developing trans-
necks with the help of excavators with a highly developed supporting surface:
single-bucket excavator TE-3M on widened tracks; one-
bucket excavator E-652B on sleighs, foam drags and flat
floating pontoons; swamp excavators MTP-71 (EO-4221) or
ECB; excavators TE-3M, MTP-71 (EO-4221) and EKB and some
Equipped with various types of interchangeable equipment excavator
tor can perform the following types of work:
1) dragline - digging trenches and pits in swamps, swamps
floodplains of rivers, as well as rivers and reservoirs with a depth of not more than 0.9 m ;
2) grab - development of trenches and pits in swamps, rivers
and reservoirs with a water level height of more than 0.9 m. At the same time, the excavator
walks afloat, keeping from arbitrary movement or
flow with the help of a rope brace;
3) backhoe - digging trenches and pits in conventional
ground conditions;
4) by crane - hanging weights on the pipe, production
loading and unloading and installation work in the swamps, as well as
max rivers and rivers with a water level of not more than 0.9 m.
ensure the patency and operation of the excavator in the swamps of all
types. Centralized tire inflation system with control panel
in the driver's cab provides the necessary increase in pressure in
tires when moving and working on hard ground and reducing its
on swampy and soft soils.
question number 21 option 3
Ballasting and securing pipelines at design elevations
can be carried out in one of the following ways: backfilling of pipe
wires with mineral soil; concreting of the pipeline; mouth-
novkoy on the pipeline of single reinforced concrete cargoes of various
structures; fixing pipelines with anchor devices;
filling the inner cavity of the pipe with water, oil or oil
ducts (for oil pipelines and for oil product pipelines) (Fig. 8.5).
All means of balancing can be divided into two main
The first group includes devices that act on pipes
wire own weight:
a) single reinforced concrete loads;
b) group installation of single reinforced concrete loads;
c) single iron weights;
d) mineral backfill soil (usually used when raising
deepening of the pipeline);
e) fixed hydrophobized soils;
f) polymer-container ballasting devices (PCBU),
filled with local or imported soil or crushed stone;
g) mineral soil in a sheath of non-woven synthetic
materials;
h) continuous concreting of pipes;
i) anchor plates;
j) combined methods, etc.
The second group includes anchor devices that carry support
b) drop-down type;
c) fired;
d) explosive;
e) frozen;
f) pile cantilever type;
ability;
j) anchor injectors, etc.
question number 21 option 4
anchor devices, bearing spo-
the property of which is determined by the properties of soils:
a) screw anchor devices (VAU);
b) drop-down type;
c) fired;
d) explosive;
e) frozen;
f) pile cantilever type;
g) anchor anchor devices;
h) gantry anchor devices;
i) screw anchor devices with increased retention
ability;
j) anchor injectors, etc.
question number 21 option 5
The team for the installation of screw anchors consists of 6 people; VAG machinist, sump operator, bulldozer operator, electric welder, pipelayer and insulator. The screwing of the anchors is carried out, as a rule, after the pipeline has been laid in the trench. The manual method of screwing anchors is very laborious and can only be recommended in special cases. The mechanization of fixing the pipeline with anchor devices depends on their type, pipeline diameter and working conditions. The most widely used are screw anchors with a blade diameter of 150 - 500 mm, for screwing which machines such as VAG, MBTA, MZVK-rotators are used. Hydraulic anchor rotators VAG101, VAG203, VAG204 are attachments on tractors T-100 M or T-130 G, VAG201 - on excavator E304V, VAG202 - on pipelayers T1224V or T1530V, VAG205 - on skidder TDT-55. The working body of the machines is a rotator, consisting of a hydraulic motor and a gearbox. Auxiliary equipment used when screwing anchors includes a trench caisson KT-1, used in flooded areas to fix the pipeline to anchors with clamps, a set of equipment KRG1 with a steam mobile installation, or a steam converter D-563 for developing permafrost soils before screwing anchors. The bearing capacity of anchor devices is controlled by a DKA-351 dynamometer. The set of machines and equipment also includes an ASB1 or SDAU welding unit for welding anchors with a collar and an ISTZB bitumen melting pot for applying a protective bitumen coating on the surface of anchor collars.
question number 26 option 1
The principle of operation of control dampers designed for
regulation of high costs, is to change their skip-
sknoy ability when turning the disk in accordance with the input signal
cash coming from the control device (control
numbering machine, automatic controller, remote control panel
management, etc.).
Shut-off and control damper with electric drive:
1 - body; 2 - disk; 3 - shaft; 4 - axis; 5, 6 - supports; 7 - pressure flange;
8 - sealing rings; 9 - pin; 10 - rubber ring;
11 - clamping ring; 12 - manual override
question number 26 option 2
There are several types of shutoff pipeline actuators.
fittings:
Electric drives;
Pneumohydraulic drives;
Pneumatic actuators;
Hydraulic drives;
With mechanical gear.
question number 26 option 3
Check valves are protective fittings and are used for
prevent the reverse flow of the medium on the linear part of the pipeline
water and thereby preventing an accident, for example, in the event of a sudden
stopping the pump. On fig. 13.14 shows a general view of the check valve.
It is an automatic self-acting safety
device. The shutter is the main assembly of the check valve. He skips
medium in one direction and shuts off its flow in the opposite direction. Valve-
we are not shut-off valves.
Swing check valve DN 50–600 mm
question number 26 option 4
To protect the vessels of apparatuses, tanks, pipelines and other
technological equipment from destruction at excessive
pressure relief valves are most often used.
With an increase in pressure in the system above the permissible safety
ny valve automatically opens and dumps the necessary
redundant working environment, thereby preventing the possibility of an accident. By-
after the end of the discharge, the pressure decreases to a value less than the beginning
valve actuation, the safety valve closes automatically
increases and remains closed until the system again increases
the pressure is higher than allowed. On fig. 13.15 shows a cargo pre-
safety valve. Safety valves are designed
for liquid and gaseous, chemical or petroleum media,
The tightness standards in the valve must comply with GOST 9789–75.
Cargo relief valve
question number 26 option 5
| Scheme | ball valve |
Tap is a locking device consisting of a body and a plug, in
in which the plug has the shape of a body of revolution with a hole for passing
liquid or gas. On fig. 13.8 shows a diagram of a ball valve
porno with electric drive. The tube rotates around its axis.
On fig. 13.9 shows the valve plug seal.
Crane schemes:
a - conical; b - cylindrical; in - spherical;
1 - body; 2 - cork; 3 - separating washer; 4 - gland packing;
5 - stuffing box; 6 - shank
Cranes are also classified according to other design features.
signs, for example, according to the method of creating a specific pressure on the seals
surfaces, according to the shape of the plug passage window, according to the number of
dov, by the presence or absence of a narrowing of the passage, by the type of control
and drive, according to the material of the sealing surfaces, etc.
(Fig. 13.11).
Advantages of cranes:
Low hydraulic resistance;
Straightness;
Simplicity of design;
Small overall dimensions and weight;
High strength and rigidity;
Reliable sealing;
Independence from the direction of movement of the medium;
Possibility of regulation of pressure and giving.
Each type of crane has its advantages and disadvantages.
very necessary