Domains. Galvanized cable: gost, dimensions, purpose. steel cable How much does 1 m of cable with a diameter of 24 weigh

Metal ropes and twisted slings based on them are necessary and critical elements of transport and construction equipment, industrial equipment and lifting devices. Steel wire ropes with organic and metal cores are used throughout. Interstate standard 2688-80 defines the types of double lay products with an organic core and linear contact with steel wires.

Ropes of a similar design, but with a metal central strand, are produced in accordance with GOST 7668-80.

Steel rope GOST 2688-80 consists of six wire strands which are twisted into one concentric surface around an organic core.

Natural and artificial materials are used as an organic core, such as:

sisal;
hemp;
cotton yarn;
nylon threads;
nylon;
polyethylene.

The core material is impregnated with grease, which protects it from decay and increases the product's useful life. GOST 15037–69 greases are mineral oils containing solid hydrocarbons and copper salts. The organic core provides the necessary resilience and flexibility to the steel cables.

Each metal strand of LK-R consists of 19 round wires, twisted into three layers. The outer layer contains wires of different diameters, which provides a linear type of contact in the strands, uniformity and strength of the rope surface. LK-R strand ropes have high durability and performance.

The design feature is the direction of twisting of the rope elements. The direction of twisting the wire in the strands can be left and right. The combination of the directions of the elements during lay-up sets the properties of the cable. One-sided lay ropes are flexible, wear-resistant, but easily untwisted under load. Non-expanding structures are made by means of cross or combined stranding.

Round wire for steel ropes is made of uncoated carbon steel or with a galvanized outer layer.

The range of products with organic core and steel wire shell, defines GOST 2688–80. Steel ropes are subdivided according to their mechanical properties, purpose, type of wire material, method and direction of stranding, according to manufacturing accuracy and degree of balance.

Classification differences

According to their purpose, cables are divided into types:

GL - gruzoludskie, which are used when lifting, lowering, moving people and goods.
Г - cargo, they are used for transportation and fastening of goods.

By mechanical properties, brands are distinguished:

1 - the quality is normal.
VK - high quality.
B - high quality.

By the type of wire used:

without outer cover;
with a galvanized layer.

Depending on the density of zinc, the following types of galvanized wire are distinguished: coolant, C, J. Wire ropes with coolant coating are suitable for use in particularly harsh conditions and corrosive environments. For standard operating conditions in air, wire ropes of uncoated or coated group C are suitable.

In the direction of wire twisting:

Left lay - denoted by the letter L.
Right lay - no designation.

By the combination of wire and strand directions:

One-way lay: with the same direction of wires and strands in the rope.
Cross: with the opposite position of the wire and strands.
Combined: when the strands of the right and left twisting directions are used simultaneously when laying the cable.

By lay method:

Non-expandable - denoted by the letter N.
Unrolling - no symbol.

According to the manufacturing accuracy, constructions are distinguished:

increased accuracy - T;
normal.

By balance:

unaligned;
flattened - R.

The balance of a metal rope is determined by the fact whether straightening was used in the process of its production - straightening of the strands. This process relieves stress on the rope so that the product remains straight after twisting.

Symbol

All symbols specified in GOST, apply when marking ropes. The first digit of the marking is the diameter of the cable section, followed by the designation of the type of purpose, quality grade, coating group, direction of the lay, curl characteristic, indication of straightening, accuracy and designation of the marking group.

For example: Rope 28 - G - 1 - L - 1670 GOST 2688–80. The designation of untwisted non-aligned right lay cables, normal manufacturing accuracy and from uncoated wire will be shorter due to the absence of letters and numbers of the conventional designation. Only the diameter, purpose, quality group, left lay direction and marking group are indicated.

Straightened, non-twisting cables of high quality and manufacturing accuracy, made of wire coated with coolant, will have the following marking: Rope 21 - GL - V - ОЖ - Н - Р - Т - 1470 GOST 2688–80.

Marking groups, dimensions and weights

The last number in the designation of the rope - a marking group that indicates the strength characteristics of the rope. The higher the number, the stronger the cable and the more loads that it can withstand during operation.

According to GOST 2688-80, ropes with a cross-sectional diameter from 3, 6 to 56 mm with strength characteristics from 1370 to 1860 N / mm 2 (140-190 kgf / mm 2) are produced. The tables of the standard indicate the diameters of the ropes, all wire layers of strands, strength characteristics and the approximate weight of 1 thousand meters of rope. The weight of a steel rope GOST 2688–80 can be determined by multiplying the weight value of 1 thousand meters of rope taken from the table by the length of the rope and dividing the value obtained by 1000.

1 thousand meters of rope with a diameter of 12 mm weighs approximately 520 kg; with a diameter of 21 mm - 1630 kg. The weight of one meter of a product with a thickness of 37 mm will be approximately 5 kg, and of one meter with a thickness of 56 mm - 11.6 kg.

Steel rope (wire rope) - extra strong wire hoisting equipment. It combines the strength of reinforcement and the flexibility of a wire, eliminating their disadvantages. Most often, steel ropes are used in construction as load-bearing elements of structures. With their help, heavy and super-heavy loads are transported, the products are used for overlapping stadiums, sports grounds and fastening bridges.

Ropes produced according to different GOST standards have a specific purpose, which is associated with different levels of strength:

Types of steel ropes

There are many varieties of steel ropes. To make it easier to navigate the assortment, they are classified according to their characteristics.

Core material

The element itself is necessary to enhance wear resistance, flexibility and product strength. The core extends the service life of the entire rope and reduces the risk of deformation.

There are two options for cores: from metal (MC), as well as from organic materials (these can be both natural and synthetic fibers, they are designated OS).

The second type of core is made from hemp or polypropylene. It is additionally impregnated with anti-corrosion substances, as well as compounds that protect against decay. The metal core increases the load capacity and makes it possible to work in more severe conditions, at very high temperatures.

Design

Depending on the number of weaves, there are the following ropes:

Single (also called spiral). They are made of three layers of spirally woven wire.
Double lay - made of weaving in several layers.
Triple lay - when creating the rig, double lay ropes were used.

Strand type

Depending on the area of contact with the wire, steel ropes are divided into the following types:

point touch

Type of: Point
Designation: TC

linear touch

Type of: Linear
Designation: OK

Type of: Point-linear (with the same diameter)
Designation: LK-O

the same wire diameter of the steel rope

Type of: Linear contact of the wire with different diameters of the outer strands
Designation: LK-R

Type of: Linear contact of the wire, between the layers of which there are wires with different diameters and with the same
Designation: LK-RO

Type of: Point-to-Line Touch
Designation: TLK

By the way of twisting

By the degree of poise

By the mechanical properties of the wire

With the following designations, the manufacturer indicates the quality of the wire, which happens:

high - VK;
elevated - B
normal - denoted by one.

Wire surface coatings

The surface may not have a coating, which is not tolerated by a separate designation. Or a zinc coating can be applied, which allows the ropes to be used in special conditions:

Coolant - especially hard;
F - hard;
C - medium aggressive;

Cross - the direction of the strands is opposite to the direction of the rope.

One-sided (O) - the direction of the strands in the rope and the wire in the strands are the same.

Combined (K) - the presence of both right and left lay directions in the rope.

By appointment

Cargo-handling (GL) - for the transportation of personnel.

Cargo (G) - to move cargo objects.

Production and marking of steel wire rope

Industrial production of steel ropes is carried out on specialized equipment. The whole process is automated, so the density of the weave of the product is very high. There are several ways to manufacture products. One of the standard methods is to crimp the wire strands in a circle to deform them.

How steel rope is made

At the manufacturing plant, each product is created in accordance with GOST. A tag with the required marking is attached to the steel rope. It contains all the necessary information for the buyer:

name of the manufacturing company,
rope number,
symbol,
length,
weight in kg,
date of manufacture.

Example of marking:

12 GL V L O Z N R T 1770 GOST 2688-80

Decoding:

12 - rope diameter
GL - gruzolyudskoy
B - wire grade
L - left lay
О - one-sided lay
F - galvanized group F
H - non-rotating
P - straightened
1770 - marking group

Steel rope packing

GOST 11127-78 on steel ropes for sale and transportation prescribes packaging by winding the product on a drum. The ends are tightly attached to the structure. The drum neck must exceed 15 cable diameters, the drum side must protrude 2 cable diameters with a rope thickness of 25 millimeters. The end of the rope is wrapped from the outside with synthetic or natural materials. At the request of the customer, heavy ropes can be sheathed with boards with a maximum gap of no more than 50 millimeters. So it can be wrapped in waterproof paper according to GOST 515-77.

Rejection of steel rope

After the start of operation of the product, the steel ropes are monthly inspected for defects. Inspections are carried out by engineering and technical specialists at the enterprise.

Steel rope is rejected based on the following criteria:

the presence of wire breaks at the end fittings;
places of large concentration of wire breaks;
external and internal wear, the presence of corrosive changes;
wire exit from the lock;
breaks in strands;
reducing the diameter of the rope;
crushing strands;
the presence of bends;
deformation due to temperature or electrical discharge.

The presence of a critical number of damages and deformations of the steel rope indicates its marriage, therefore, the product can no longer be used.

Considering the main characteristics, it is possible to select a suitable steel rope for specific work, for example:

Single-weave round wire products are used at increased loads. They have high stiffness values, so these ropes are suitable for power lines and as cables protecting the load.
Double braiding of the rope provides the product with special strength. Therefore, it is preferred when there are strong end loads.
Steel rope LK-R is used for work in the open air, for example for construction cranes or any other lifting equipment. Since changes in temperature and different weather conditions, among other things, affect the wear of the material, it is optimally suited for such working conditions.
Steel ropes LK-O are highly resistant to wear and are used in aggressive environments. The outer layer of such a cable is made of large diameter wire, which allows the cable to be used for a long time. LK-O are widely used in elevators, on large ships, in the mountains when organizing rope bridges.

Cables are products that are twisted from steel wires or twisted from vegetable and synthetic fibers. On ships and auxiliary vessels of the Navy, ropes are used as standing and running rigging, mooring lines and tugs, in lifting devices, for fastening objects on a ship, for diving operations, in mine-sweeping business, in devices and mechanisms, in rigging and other works.

Material, construction and classification of steel cables. Steel cables used on naval ships are made of high-carbon galvanized steel wire with a diameter of 0.4 to 3.0 mm with a tensile strength of 130 to 200 kgf / mm2. The zinc coating of the wire, which protects the cable from rusting, is of three groups: for light working conditions - LS; for average working conditions - SS; for harsh working conditions and in sea water - ZhS. The wire is produced in three grades: B, I and II. The highest quality wire with high viscosity and mechanical strength is wire of grade B (highest), followed by wire of grades I and II. By design, steel cables are divided into three types: single, double and triple lay.

T rosyodinar and in and in k and consist of one strand, in which wires of the same diameter are twisted in a spiral in one or several (up to four) layers around one of the wires (Fig.4.1 ). The number of wires and layers in a strand is indicated in the cable characteristic by the sum of numbers, in which the first number indicates the presence of a central wire, the second - the number of wires in the first layer from the center of the strand, the third in the second layer, etc. The sum of all numbers indicates the total number of wires in strands. For example, writing 1 + 6 + 12 means that there are nineteen wires in the strand, of which six are twisted in the first layer and twelve in the second, one wire is the central one.

Rice. 4.1. Single lay spiral single strand cable

If the wires of one layer are twisted in the same direction as the wires of adjacent layers, then all layers will touch along the entire length of the wires (Fig. 4.2).

Rice. 4.2. Linear tangency of wires in strands

A cable twisted from such strands is called a cable with a linear touch of the wires and is denoted by the letters LK. When each subsequent layer of wires is wound in the direction opposite to the previous one (the wires of individual layers of the strand lie at an angle to the wires of adjacent layers and touch them at the points of intersection), a cable with a point contact is obtained - TK (Figure 4.3).

Rice. 4.3. Point contact of wires in strands

Single lay cables are otherwise called spiral or single strand. They are used in various devices and mechanisms. Ropes made of soft galvanized wire with a tensile strength of 50-90 kgf / mm2 are called benzene ropes. These ropes are very flexible and are used for applying benzels, making chain mail patches and in various rigging works.

Rope ropes are called cable work ropes. They are made by twisting several strands in one or two layers around a single metal, organic or mineral core (Figure 4.4).

Rice. 4.4. Double lay rope cable work: a - with a metal core; b - with organic or mineral core

Three-strand ropes are twisted without cores. (fig. 4.5).

Rice. 4.5. Three-strand rope

The center core fills the void in the center of the cable and prevents the strands from falling into the center. The metal core is an ordinary wire strand or a steel cable twisted from several strands; in the first case, the cable is called all-metal, in the second - a cable with a special wire core. Organic cores made of hemp, manila, sisal or cotton fabric contribute to the formation of a round rope shape and, being impregnated with anti-corrosion, anti-rotting grease (petroleum jelly, gun grease, rope ointment, etc.), protect the inner layers of the wire rope from corrosion, reduce friction between them and thus lengthen the service life of the rope. Mineral cores are made from asbestos and are used in ropes for high temperature applications. Wire ropes are used for standing rigging, making mooring lines, tugs, trawls, various slings, lashings, pendants; they are used for guineas and running rigging.

Cable work ropes (lapel) are called cables. They are twisted from several cables of cable work, which in this case are called strands (Fig. 4.6). Wire rope ropes are made of thinner wire than wire rope ropes. They are much more flexible than the latter, but at the same time weaker by about 25i / o. Cable work ropes are used mainly where special flexibility is required, for example, on light lifting mechanisms with rope winding on drums, for blades of boat hoists, etc. Thick cables with a diameter of 40-65 mm go to mooring lines and tugs.

Rice. 4.6. Triple lay cable work rope

The most widespread are cables of cable work, and especially six-strand ones, twisted around a hemp core.

Strands of double and triple lay cables consist of wires of the same or different diameters, twisted around a central wire or an organic (mineral) core in one or more layers. In the characteristic of the cable in the presence of strands with an organic core, zero is set instead of one. Writing 0 + 9 + 1 5 means that the strand has 24 wires twisted in two layers of 9 and 15 wires around an organic core. The wires in separate layers of the strand can have linear, point and point-linear tangency - T LK (Figure 4.7).

Rice. 4.7. Point and linear tangency of wires in strands

LK-type cables can have wires of the same diameter in all layers of the strand - LK - O, two different diameters in the upper layer of the strand - LK - R, different and the same diameter for individual layers of the strand - LK-RO and a smaller diameter filling the space between two layers, - LK - 3.

TK-type cables have wires of either the same diameter, or two different diameters in separate layers of the strand.

TLC-type ropes can have wires of one diameter, two diameters and different and identical diameters.

The area of filling the section of the cable of the LK type with metal is 13% higher than that of the cable of the TK type, the total breaking strength of the cable is the same value. The performance of the LK-type cable is 1.5-2 times higher.

Steel cables have right and left strand stranding directions. In the first case, the strands in the cable twist clockwise and form a direct descent cable (Fig. 4.8.6, c); in the second - counterclockwise, forming a reverse descent cable (Fig. 4.8, a).

By the type of lay, the cables are one-sided, cross and combined lay. A cable in which the direction of the lay of the outer layer of wires in the strands and strands in the cable is the same is called a one-way lay cable (Fig. 4.8.6). A cable in which the direction of the lay of the outer layer of wires in the strands and strands in the cable is different is called a cross-lay cable (Figure 4.8, a). A cable twisted from strands, half of which has a right lay of wires, and the other half has a left one, is called a combined lay cable (Figure 4.8, c).

For one-sided lay cables, the wires are located at an angle to the cable axis, for cross-lay cables - parallel to the cable axis, for combined lay cables - for a fir tree.

Rice. 4.8. Steel cable: a - left cross lay; b - right one-sided lay; в - right combined lay

Manufacturing plants produce cross (right) lay cables. They are the least susceptible to unwinding, do not require special handling and are most commonly used on ships. Other types of lay ropes are made only at the request of the customer.

The design of a steel cable is usually characterized by the formula

where n is the number of strands in the cable;
m is the number of wires in the strand;
l is the number of organic cores in the cable.

For example, the notation 6 x 30 + 7 means that the rope is twisted from 6 strands, each strand is twisted from 30 wires, the rope has 7 organic cores, of which one is common, and one in each strand. For a more detailed designation of the structure of the cable, in front of the formula, letters are placed that characterize the lay of wires into strands and the ratio of wires by diameter. TK 1X19 means a single strand cable with 19 wires in the cable when they point to point contact. LK - 0 7 X 7 means a seven-strand all-metal cable, 7 wires of the same diameter in a strand, with a linear touch in each of them.

The full characteristic of the cable is indicated by numbers and letters written in a specific order. For example, the record LK-RO 6 x 3 6 + 1 - 1 8 - N - 1 7 0 - V - Zh S - L - O, GOST 7668-55, means a cable with a linear touch of different and equal diameters of wires on separate layers of the strand , six-strand, 36 wires per strand, with one central organic core, diameter 18 lsh, non-twisting (cable, the wires of which are spirally shaped on special machines), made of wire with a tensile strength of 170 kgf / mm2, grade B, for harsh working conditions , left one-sided lay, GOST 7668-55.

In the characteristics of a specific cable, other designations are also used: NK - a non-rotating cable that does not rotate around its axis during operation (used for rescue, hydrological and other work); K - combined lay rope.

The right-hand cross rope (ordinary, untwisted) does not have a special letter designation.

Steel cables are rigid and flexible. Rigid ropes are made from a small number of large diameter wires, with or without one organic core. They are very durable. Flexible ropes are made from a large number of thin wires and have one or more organic cores. Individual steel ropes are as flexible as plant ropes. Flexibility of cables can be compared using the coefficient of flexibility of the cables (Table 4.1).

Table 4.1

Table 4.2

Measurement of steel cables, breaking and working strength, calculation of cables. The thickness of the wire rope is measured by diameter in millimeters (mm). With an even number of strands, the thickness of the cable is measured with a caliper (Fig. 4.9), with an odd number - with a tape. In the latter case, the measurement result must be divided by 3.14.

Rice. 4.9. Measuring the diameter of the cable with a caliper:

Steel ropes at the request of the customer can be manufactured for any length, but not less than 200 m. The most common ropes are 250, 500, 750 m long.

The relative elongation of steel cables (the ratio of the absolute increment of the cable length during stretching to its initial length) is no more than 3%. This is their disadvantage, since the cables break with sudden jerks.

The weight of the steel cable W in kg is selected from GOST or calculated:

where K is the coefficient;
l - cable length, m;
d - cable diameter, see

For single strand spiral ropes K = 0.52, for three strands without an organic core K = 0.40, for ropes with one organic core K = 0.37, for ropes with several organic cores.

Split edge (strength, breaking force) - the minimum load at which the cable breaks. The value of the breaking strength R in kgf of a particular cable is selected from GOST or calculated:

where K is the coefficient;
d - cable diameter, mm.

For single strand spiral ropes K = 70, for ropes with one organic core K = 40, for ropes with several organic cores K = 34.

Note. When measuring the rope around the circumference, the coefficient K is accordingly taken equal to 7.0; 4.0; 3.4.

The handling for certain working conditions is carried out according to the working bracket (the permissible tension that the cable withstands during operation for a long time without violating the integrity of individual wire or the entire rope).

The value of the working strength of the cable P in kgf:

where R is the breaking strength of the cable, kgf;
n is the safety factor.

For ropes used in standing rigging, n = 4, for running rigging and lifting loads n = 6, for lifting loads at high lifting speeds n = 6/1 0, for lifting people n = 14.

Example. Pick up a steel flexible cable for lifting a load of 2000 kg. The rope is based on a single pulley movable unit (the weight W is held by two ropes).

SOLUTION. According to formulas (4.3) and (4.4) tension (working strength of the cable):

With an 8-fold safety factor, the breaking strength of the cable
and the diameter of the cable with 7 organic cores
The diameter of the cable can also be determined according to GOST. To do this, in the table GOST 3084-55 (table 4.7) we select the breaking strength of the cable, looking for the number closest to 8000 kgf in the column "Breaking force of the cable as a whole". For a cable with a tensile strength of the wire in tension of 140 kgf / mm2, such a breaking strength is 8240 kgf and corresponds to a cable with a diameter of d = 15.5 mm.

Table 4.3-4.9 contains the data established by the state all-Union standards for steel cables, the most widely used on ships and auxiliary ships of the Navy.

Rules for the acceptance of steel cables. The ropes are delivered on wooden or metal drums or in coils tied in 4-6 places (for ropes up to 30 mm in diameter with a maximum weight of 700 kg). The cables used for lifting and lowering people are supplied only on drums.

Each cable is provided with a tag attached to the drum or coil, and a certificate. The tag indicates: plant, cable serial number, symbol, length, weight, date of manufacture and GOST of the cable. In addition, the certificate specifies: the type of cable and its symbol, direction and type of lay, galvanized group, calculated tensile strength of the wire and the total breaking resistance of all wires in the cable, breaking strength of the cable as a whole.

Table 4.3. Notes: 1. Cables, the breaking strength of which is indicated to the right of the bold line (Table 4.3-4.9), are made of light-colored wire.
2. GOST 2688-55 provides for the manufacture of cables with an estimated tensile strength of cables of individual diameters and above 180 kgf / mm2, namely: 190, 200, 210, 220, 230, 240 kgf / mm2.

Table 4.4. Note. GOST 3062-55 provides for the manufacture of cables with an estimated tensile strength of cables of individual diameters of 120 kgf / mm2 and above 180 kgf / mm2, namely: 190, 200, 210, 220.230.240 . 250.260 kgf / mm2.

Table 4.5. Note. GOST 3066-66 provides for the manufacture of cables with an estimated tensile strength of cables of individual diameters of 120 kgf / mm2 and above 180 kgf / mm2, namely; 190, 200, 210, 220, 230, 240, 250, 260 kgf / mm2.

Table 4.6. Note. GOST 3083-66 provides for the manufacture of cables with an estimated tensile strength of individual diameters of 120 kgf / mm2 and above 180 kgf / mm2, namely: 190, 200, 210, 220 kgf / mm2.

Table 4.7. Note. GOST 3084-55 provides for the manufacture of cables with an estimated tensile strength of cables of individual diameters of 120 kgf / mm2 and above 180 kgf / mm2, namely: 190, 200, 210, 220 kgf / mm2.

Table 4.8. Note. GOST 7668-55 provides for the manufacture of cables with an estimated tensile strength of cables of individual diameters of 120 kgf / mm2 and above 180 kgf / mm2, namely 190 kgf / mm2.

Table 4.9. Note. GOST 7673-66 provides for the manufacture of cables with the strength of cables of individual diameters 120 kgf / mm2 and above 180 kgf / mm2, namely: 190, 200, 210, 220 230 240, 250, 260 kgf / mm2.

When accepting the cable to the ship, it is necessary to carry out a thorough external examination and measure it, as well as check the structure. Inspection of the cable consists in checking its lay, which must be uniform along its entire length. The cable should not have broken, criss-crossing, broken and weaker tension than other wires. There should be no dents, cuts or rust on the surface of the wire rope; the cable must be round throughout its length. Galvanized wires must be strong, without cracks. The strands of the rope should not have weakening, kinks, protrusions and sinking. The organic cores should not release lubricant and protrude from the inside of the rope.

After an external inspection, the cable is measured and its actual design is checked against the data indicated on the tag and in the certificate, for which the end of the cable is slightly uncoiled and the number of strands, wires in the strands and the number of organic cores are recalculated; check the location of the strands in the cable and wires in the strands. The design of the cable must comply with the data specified in the requirement of the ship.

All data and results of the inspection are recorded in the cable book.

Working with and maintaining steel cables. The cables must be suitable for the working conditions. A rigid cable, for example, cannot be used as mooring lines, pass through blocks, as it will wear out quickly. Flexible rope is used for mooring lines, tugs and equipment for lifting devices.

The direction of the lay and the order of winding the cable on the views, the drums of the capstan and winches are selected so that the cable is additionally twisted during operation. This increases its density and, consequently, its service life.

When loading and unloading, a rope wound on a drum must not be thrown or subjected to strong impacts, since if the drum breaks, it can get tangled, and it is difficult to untangle it.

The formation of loops is unacceptable, since when the cable is pulled, they form a fold - a kolishka, which sharply reduces the strength of the cable and makes it unusable. The buttonhole should be carefully and correctly unrolled, not allowing the half-rolled buttonhole to be pulled out. When opening the bay, the cable is wound around the outer end, while simultaneously rotating the bay or drum (Figure 4.10), and immediately wound on the view or laid on the deck in the bay.

Rice. 4.10. Opening of coils and drums of steel cable:
a - correct; b - wrong

Before cutting off a piece of steel cable of any length from the bay, in order to avoid unwinding, two brands of soft wire or benzel are applied to the cable. The distance between the marks should be from one to four cable diameters; the length of each brand is at least 5 times the diameter of the cable. The steel cable must be fastened in eights and only on double bollards, pinning the two upper hoses.

When mooring at mooring lines and at the mooring itself, one must not allow one cable to pinch the other or go along the other. Before being fed to another ship (shore), the cable is stretched on the deck and the loops are straightened. If it is necessary to lay it on the deck, the cable is circled into a bay of large diameter and the laid hoses are tucked through one.

When winding on a drum, the cable should be padded with a wooden fly; it is impossible to use a metal sledgehammer to avoid damage to the galvanized coating and subsequent rusting of the cable.

Knots of steel, even flexible, cable should not be knitted. Two steel cables are connected by means of a bracket inserted into the thimbles at the ends of the cable. With high-quality splitting, the loss of rope strength is about 15% - for cables with a breaking strength of a wire of 120-130 kgf / mm2, about 20% - with a breaking strength of 140-150 kgf / mm2 and up to 30% - with a breaking strength of a wire of 160-170 kgf / mm2. It is not allowed to splash ropes intended for lifting and lowering people.

In places of contact with sharp protruding parts, wooden spacers or mats are placed under the cable.

During operation, the cables must be lubricated regularly. The grease, which has anti-corrosion and anti-rotting properties, significantly increases the service life of the cables. A good lubricant is rope grease (industrial rope IR). Also used are technical petroleum jelly (universal low-melting UN), gun grease (UNZ), synthetic solid oil (universal medium-melting synthetic US) and fatty grease (universal medium-melting US). Technical petroleum jelly and cannon grease are heated to 60-80 ° before use.

Do not use fuel oil, solar oil, waste engine oil and other substances containing acids and alkalis for lubricating cables.

The ropes are lubricated at least once every three months and every time after the rope has been in the water. The cables stored on the ship are lubricated at least once a year. Before lubrication, old dried ointment and dirt are removed from the cables with metal brushes. Apply the lubricant in a non-greasy layer with chewing gum or rags. If rust is found, the cable must be reeled off the view, cleaned of rust, wiped with a rag dipped in white spirit, wiped dry, lubricated and wound around the view. The preserved grease is removed with a rag.

If the cable, according to the working conditions, must be in sea water, it is useful to lubricate it with a boiled hot mixture consisting of equal parts of wood resin and lime. After work, the cable is washed with fresh water, dried, lubricated and wound around the view.

Organic core cables should not be held in high temperature locations as the cores may burn out.

Broken wires are cut short, and the cable in these places is rounded with soft wire. Strong wire marks are applied to the ends of the cable to prevent unwinding.

In accordance with the requirements of the Naval Regulations of the Navy and the Rules for the Operation of Hulls, Devices and Systems of Ships and Support Vessels of the Navy, daily and periodic (at least once a month) inspections and checks of all cables must be carried out. Deficiencies are eliminated immediately, and worn-out cables are replaced with new ones.

Storage and service life of steel cables. Steel cables in use are stored in tightly wound rows on views, covered with canvas covers, or rolled into bays, laid on wooden banquets. In sunny weather, the covers are removed. The cables stored in the ship's storerooms are lifted to the upper deck at least once a year, their condition is checked and the lubricant is changed. Storerooms must be dry and regularly ventilated.

With proper care, the lifespan of the standing rigging ropes is virtually unlimited. For ropes of running rigging, mooring lines, hoisting ropes, it is equal to 2-4 years. Ropes for lifting loads and people are considered unsuitable for use if the number of broken wires along a length equal to eight cable diameters is more than 10% of their total number or a whole strand has broken.

Excessive bends in the cable are also harmful, therefore, pulleys, rollers, drums that go around the cable during operation must be carefully selected. The diameter of the drums and pulleys must be at least 4 diameters for the cable work cable, and at least 18 diameters for the cable work cable. When using a cable in booms and hoists, the pulley diameter must be at least 300 times the diameter of the cable wire.

The service life of the ropes is significantly influenced by the diameter of the bales of pulleys, rollers or drums and the condition of their surfaces. Marine practice recommends the following bale diameters, depending on the diameters of the cables (Table 4.10).

Websites, like flowers and cars, need care. If the site is launched and no one cares about it, then sooner or later it will stop working. But the site is not just text and pictures, it is the face of the company on the Internet, a sales channel. And when the site stops working, at first glance, nothing happens, but over time there are fewer calls and customers. Those who visit your site will think that the company has closed - after all, its site is no longer working. Those who were looking for your company on the Internet will not be able to find it - again, the site does not work. Only competitors will be pleased.

"We ordered a site in our local web studio, paid for everything, and now our site is gone. The web studio does not take phones, does not answer letters, we came to their office - it turns out they moved out a long time ago." Unfortunately, this is a typical situation. It also happens "a programmer was working on our site, he quit with all the passwords", "the company underwent a reorganization, while we were dealing with matters and lost the site" and of course "I do not understand anything about your Internet, help me fix our site."

"My company, LLC" YugPodzemCommunications "is engaged in the laying and maintenance of external pipelines, the site was made by local Krasnodar developers back in 2008 and everything was fine - they followed it, updated it, it was easy to find it in Yandex. But I don't know what happened - either the crisis, or the business of doing their own thing, tired - an employee comes up to me and says - Andrey Yuryevich, our site does not work, today the second client has already said this. I call the programmers - and there "the phone is not available." everywhere, by service cars. What to do. I called my friends - they gave me a contact with the St. Petersburg guys, they fixed my website and keep it. Thank you! Respectfully, A.Yu. Mostovoy. "- client site ugpc.ru

STEPS FOR SITE RESTORATION:

Call us at 8-800-333-16-58 or write to e-mail [email protected] to clarify the cost and timing of work. It is not cheap to restore a domain and a website, but the company's reputation losses and the cost of creating a new website are much higher than the cost of restoration work. The basic term for domain renewal is 3 business days, site restoration is 5 business days.

Fill out an application for a domain for an individual (download the application) or send the details of your legal entity. For work, the cost of which is from 7000 rubles. it is possible to conclude an agreement (download the agreement). You pay for the work.

What is a domain:

A domain is the address of a website on the Internet, a set of letters and numbers, like a phone number. The address of our site is dra.ru, the address of Vkontakte is vk.com, and the address of Yandex is yandex.ru. Domains are registered and maintained by domain registrars. Each site on the Internet has its own domain. Your site has the same, only now the domain is not working and it needs to be restored.

Who the domain is registered for:

To an individual or a legal entity at your request. If you are an individual entrepreneur, then from the point of view of the legal status of domains, the domain is registered for you as an individual. For some domain registrars, registration is also possible for non-residents of the Russian Federation (foreign individuals and companies).

Who owns the domain:

A domain is not an object of property rights (like an apartment or a car), therefore, from a legal point of view, it does not have an owner. Domain is an entry in the registry of a domain registrar that has an Administrator who, in fact, is the owner (manages the domain, renews, can transfer the domain to another administrator). You can check who the domain administrator is through the Whois service at the registrar, for example, in Axelname - if in the Org field: it says KreoBits or CreoBits - then we have the domain, if Private person means the domain of a private person (in accordance with Federal Law 152 on personal data, the registrar does not have the right to indicate the full name in public data and therefore "Private person" is written for all individuals).

We create an account (agreement) with an accredited domain registrar according to your profile of an individual or the details of a legal entity and we carry out registration of a domain for you. We create a new hosting for the site and rebuild the site pages with text and pictures on the modern MODx site management system. As a result, we get a completely working site that looks and is filled in the same way as the site that you had before. We send you passwords for the domain, site editor and hosting.

What is hosting:

In order for the site to be accessible via the Internet, it must be placed on an Internet server (specialized computer). This service is called " hosting"(from the English. hosting). Technically, a site is a set of files, it is hosted and becomes accessible from any device connected to the Internet. If the hosting is good, then the site is always available, works quickly and does not break. If the hosting is bad, the site will work slowly and intermittently. We host recovered sites on equipment in the Selectel data center (Moscow), which is one of the best hosting providers in the Russian Federation.

What is MODx:

MODx is a content management system from English. Content Management System (CMS). It is needed for the site to work, drawing an analogy - as Windows is a system for controlling a computer, and Android is for a smartphone and a tablet, so MODx is the same thing, only for a site. But unlike Windows and Android, for sites there are hundreds of different in purpose and complexity of site management systems, the most common of which are 1C-Bitrix, UMI.CMS, Wordpress, Joomla and MODx. The main task of MODx, like any other CMS, is to ensure the operation of the site and convenient tools for editing it by a programmer and editor (for example, a manager of your organization). CMS are paid and free, MODx is free, all management is in Russian.

What will we restore:

Everything that we can restore, including the design of your site, its content (texts, pictures), functionality - structure, menu, search, catalog, feedback form. It's like recovering data from a broken computer (hard drive), if the specialist is good, he will restore all the files as they were.

WHAT GUARANTEES?

We are a small company, we have been working since 2007, we value each client and value our reputation. Our guarantees:

our company is not a "one-day", we are already 9 years old, it is easy to check, make an online statement of the Unified State Register of Legal Entities for CreoBits LLC (TIN 7840363309). you can also look at the arbitration practice ("cases in court") in our organization, for 9 years of work there are only two of them, in one of which we won, and the second in the process.
works for amounts from 7000 rubles. performed under the contract
DRA is a registered trademark -.
gratitude to our organization from the authority -. We have been working with the Committee for Nature Management for 7 years, we maintain and develop their website.

Better than any words:

We ask you to be vigilant, because scammers work on our behalf who do not hesitate to introduce themselves as CreoBits / DRA.RU employees and promise assistance in restoring sites and domains for a modest (or completely immodest) fee. Remember, we write only from @ dra.ru addresses, for example, from addresses [email protected], [email protected] and if you received a letter from some other address, for example, [email protected] then they are scammers. Just call us at 8-800-333-16-58 and clarify all questions on site restoration. Our website dra.ru

Construction of buildings, bridges and roads, oil and gas processing and coal industries, sea and river shipping and other industries today cannot do without a steel cable. Flexible and strong ropes twisted from steel wire are used for lifting and moving various equipment, building materials, structural elements and other loads.

Features of the structure of the cable

Steel rope is a complex metal product, which is the main element in many road-building, earth-moving, hoisting machines and mechanisms. Any cable consists of many wires twisted into strands, braiding a common core of metal or other materials.

The strength and construction of a rope depends on the number and thickness of wires in each strand, the number of cores and their material, the density and number of strands in the rope. The core of the twisted cable forms a model of the finished product and protects the surface of the rope from being squeezed under high mechanical loads. The metal core increases the structural strength of the cable and reduces its structural elongation under tension and at high temperatures.

Rust control

The main problem with steel cables, corrosion, is solved in three ways:

The original wire is manufactured from stainless steel. The method is the most reliable and expensive.
Coating of wires with zinc or chrome. The most resistant spraying is designed for several years of operation.
Combined ropes with an organic or synthetic core. Special grease impregnated cores made of hemp, sisal, beckoning or cotton minimize friction between the rope elements and extend the life of the rope. Stronger and lighter two-layer core made of polyamide threads is used in cables for extreme sports equipment.

In terms of durability - quality - price, galvanized cables with non-metallic cores are considered the most optimal. Sometimes it is provided with a water-repellent lubricant (grease or nigrol).

Quality characteristics of steel wire rope

One of the main aspects of evaluating a steel wire rope is its strength. Determined by the thickness, manufacturing method and design, the strength of the rope determines the permissible load on it. Working strength (permissible force) is determined by the maximum load at which the integrity of the cable is not violated for a long time. The tensile strength is determined by the minimum load that breaks down the steel wire rope. Without collapsing, ropes made of steel with a thickness of 2 ... 10 mm can withstand a load of 47 to 174 kg. The minimum breaking load for steel ropes ranges from 235 kg for thin 2 mm ropes to 5880 kg for ropes with a diameter of 10 mm.

Flexibility is an important criterion when choosing a cable. The more wires are twisted into a strand of steel rope, the more flexible it is. In cables of increased flexibility, each of 6 strands, braiding an organic core, is a twist of 144 wires. consists of 72 42 elements is considered rigid. In the production of steel ropes, wire with a thickness of 1 ... 8 mm is used.

Varieties of steel ropes

The classification of ropes is determined by the number of layouts:

With a single lay, the wire is wound in a spiral onto the core. Such a rope can be used both as a finished product and as an element of more complex cables.
For double stranding, ready-made single strands are used, wrapping around the core in a certain sequence. This technique is used for the production of single-layer and multi-layer ropes. Special rules of wrapping allow double galvanized ropes (strands) not only to withstand significant loads, but also not to twist during operation.
The strongest and most reliable ropes are triple layed. For their formation, the strands are produced according to a special method.

The direction of the strands during twisting can be either right or left.

Wire rope marking

The designation of the type of galvanized cable is determined by the type of weaving of the strands. Depending on the way the wires are arranged, the cables are divided into several types:

LK - linear tangency, at which the lay step in all layers is the same with a repeating pattern.
LK-O - when weaving a strand, a wire of the same diameter is used.
LK-R - the rope is formed by strands, woven from wires with different diameters.
LK-RO - strands of different types are woven during the manufacture of the rope.
TK - point contact of wires. With this weaving, each layer of the strand has its own step, and the layers intersect with each other.
TLK - a combined cable made of strands with both linear and point contact.

The correct choice of galvanized cable, depending on the operating conditions and its purpose, affects the durability and quality of the machines and mechanisms in which it is used. For example, the low density of the internal structure of TC types under dynamic load provokes strong friction of the rope layers and leads to its rapid wear.

The marking of the product also indicates the type of coating, diameter, type of lay, purpose, type of stranding, straightening, accuracy and strength.

The state standard defines the requirements for galvanized rope, GOST has each type of steel rope. For example, steel cables of the LK-O type double lay with a metal core are produced in accordance with standard 3066-80, and with organic - 3069-80, LK-O single lay complies with standard 3062-80, LK-R cables with an organic core are produced in in accordance with GOST 2688-80 and so on. These documents regulate the purpose, mechanical properties of grades, types of wire coating, direction and method of lay, combination of directions of lay of its elements in the rope, manufacturing accuracy and degree of balance. Acceptance rules, technical requirements, marking, test methods, packaging, transportation and storage standards for cables are determined by GOST 3241-91.

Steel rope application

Due to their reliability and practicality, galvanized steel wire ropes are actively used as a component of industrial equipment in a wide variety of areas:

in lifting and transport mechanisms;
in road construction, earthmoving and mining units;
in the technology of oil and gas industries;
in agricultural machines;
in shipbuilding and other industrial sectors.

A wide range of ropes of different diameters and strengths allows you to purchase the type of steel rope that matches your specific equipment.

According to their purpose, steel cables are divided into two groups: intended only for working with loads and for lifting or transporting both people and goods.

Advantages of galvanized ropes

Coating the steel wire with zinc increases the service life of the wire rope by 3 times and allows it to be used in aggressive environments. Galvanized ropes are characterized by a high level of corrosion resistance, which makes them suitable for use on river and sea vessels. Due to their high wear resistance, they are actively used in all areas of industry.

Zinc coating of steel wire divides ropes into three groups according to working conditions:

In a harsh aggressive environment.
In a particularly aggressive harsh environment.
In a moderately aggressive environment.

Sheathed rope

The modern industry offers a galvanized cable in a PVC braid, which increases protection against corrosion. Such ropes are successfully used when it is necessary to tie a load for immersion in a liquid, as guy wires when installing antennas and masts, during rigging and loading operations in adverse conditions and at low temperatures. Galvanized cable 3 mm in PVC sheath is used for overhead communication lines and power supply. Today, the range of galvanized ropes is being expanded with products coated with materials that can withstand high temperatures and resist combustion.