The slinger's job is to properly tie the loads and give commands to the crane operator to transport them. The slinging diagram serves as a guide to execution rigging work. It is a graphic image indicating methods and places for capturing cargo.
Posters are made from laminated paper, PVC film and other materials. They are designed for long-term use and are weatherproof.
Model rules
The slinger must work when he has a sling diagram. It may not always be at hand. Therefore, for loading or unloading, it is necessary to know and apply the rules of slinging according to standard schemes.
- Building elements (slabs, blocks, etc.) are moved with hooks and special loops. In this case, the number of slings and loops is selected equal, otherwise the structure may collapse.
- Loads no longer than 2 m are moved using a ring sling on a noose.
- Long items are captured by the loops of two slings at a distance from the edges of no more than 1/4 of the length. The angle between them should not exceed 90 0 due to the correct choice of their length.
- Sheet metal is moved using special eccentrics or clamps. To avoid damaging its surface, linings made of wood, rubber, etc. are used.
- Slinging of equipment is carried out using special rigging: loops, mortgages, hooks, eye bolts, etc.
- Unused sling branches should not interfere with transportation. They are strengthened so that when moving the ends do not touch oncoming objects.
- Sagging or bending of the sling on the edges of the load is not allowed. The cables are loaded evenly.
- The hook must fit the size of the loop or eyebolt.
- Rigging work must be carried out in the presence of a person responsible for their safety when there is a non-standard or developed slinging scheme.
The crane operator is given the following commands:
- myna - lowering;
- vira—rising;
- hare - stop.
Types of lifting devices
Slinging methods involve the use of the following types of rigging equipment:
- slings: rope, chain, textile;
- grips;
- traverses.
Traverses are mainly used in the form of a beam with load-handling devices at the ends. There are spatial devices made for a specific moving structure.
The grippers are produced automatic and semi-automatic.
Slings are pieces of chains or ropes in the form of rings or with end links for convenient and safe grip. Load slinging schemes must be drawn up for them. If they are not available, a person responsible for work safety must be present to show the method of capture.
Types of slings
Slings are selected to match the shape, weight and location of the center of gravity of the equipment being moved or building structure. In the absence of information, it is necessary to clarify the parameters with the person responsible for the work. If the layout is non-standard, it is necessary to determine the gripping points and their location so that the load does not tip over.
Textile slings are the most vulnerable to exploitation. They should not be used wet in the cold, as ice will destroy them. They should not be exposed to acids, alkalis or fire. Spacers are used on sharp edges.
Welded chains have higher flexibility than steel ropes. The disadvantages are heavy weight and rapid destruction when cracks appear. The condition of the circuits must be carefully monitored. They are used only in conditions high temperature, intense abrasive wear and the presence of sharp edges on the load.
A universal sling is made in the form of a loop connected by weaving to a length of 40 cable diameters or with clamps. It is also made with two loops at the ends. The number of branches can be from one to four. Steel plates can be inserted into them - thimbles that protect the cable from chafing.
Ropes are used for tying products of complex configurations. They are a type of sling made from one long branch.
Cargo weight
Slinging is prohibited if the weight of the load is unknown. It is indicated in shipping documents and on packaging. Data can be found by phone or on the manufacturer's website.
The lifting capacity of the sling is reduced:
- by 20% when tightening with a loop;
- by 10% if the angle is 45 0;
- by 30% if the angle is 90 0.
Gusts of wind significantly reduce the lifting capacity of the slings.
Load slinging diagrams may contain tables of sling load capacity, which take into account their inclination.
Cargo strapping
Capturing and moving cargo can be done without the use of embedded elements. The following methods are used for this.
- Harness with a noose - clamping with slings under your own weight. Possible cargo damage. The slings wear out quickly. For long term Sling service should be applied without twists or knots. The slinging location is selected depending on the location of the center of gravity.
- Free laying between the slings if they do not have the ability to move. Otherwise, spacers may be used.
For loads with sharp edges, chafing of ropes is not allowed. Pads are used to protect against damage. They are attached to the load or secured to slings as inventory items.
Conclusion
Proper slinging of loads is necessary to ensure work safety and prevent accidents. The slinging diagram for each specific case must be given to the slinger in the form of a graphic image, which indicates the method of strapping and the devices used.
Stropovka — This is a set of methods for tying and hooking loads for lifting and moving them by lifting machines (cranes).
The following requirements apply to slinging structures:
· sling devices, their fastening to the structure being lifted and to the lifting crane must be reliable;
· the labor intensity and duration of the slinging and unslinging operations should be minimal;
· the use of sling devices and devices must be repeated (devices must be inventory);
· slinging should be done at a distance (without lifting the slinger to the slinging site);
· slinging must prevent violation of the shape and strength of the structure, as well as its falling and overturning.
For slinging various construction materials For one-time lifting, instead of special lifting devices, you can use ordinary ropes by tying them into knots and loops. The simplest and most reliable methods of tying cargo are given in table. 2.1.
To protect ropes from chafing when tying loads with sharp edges, safety pads should be installed.
When the load is laid loosely on loop slings, its movement (regardless of the number of loops on the sling) is allowed only if there are elements that prevent displacement in the longitudinal direction.
When moving loads with sharp ribs using rope slings, it is necessary to place spacers between the ribs and ropes to protect the latter from damage. Gaskets are made from wood, cut pipes, rubber-fabric hoses, flat belts, etc.
To provide safe work For the movement of goods by cranes at a construction site, schemes for slinging transported goods are developed, which are necessarily included in the PPR.
Slinging of beams and pipes is shown in Fig. 5.2, 5.3.
When unloading pipes from gondola cars and loading them onto pipe carriers, the vehicle is installed parallel to the rail track.
The crane is located between the pipe carrier and the gondola car. The safety of loading and unloading operations is largely determined by the correct choice of load-handling devices.
Lifting of pipes can be carried out using end grips, consisting of two or more ropes with hooks at the ends.
To lift long pipes, special traverses are used that have hooks that can be fixed in different length positions depending on the length of the pipes, as well as tong grips.
Slinging of rolled metal is shown in Fig. 5.4.
Slinging diagrams, graphic representations of methods for slinging and hooking loads should be handed out to slingers and crane operators or posted at work sites. The crane owner or operating organization must also develop methods for tying machine parts and machine components moved by cranes during their installation, dismantling and repair, indicating the devices used, as well as methods for safely turning loads when such an operation is performed using a crane.
Rice. 5.2. Slinging beams:
a - metal (in girth); b - reinforced concrete (in girth); c — metal (traverse with pincer grips); 1 — spacer
It is especially necessary to develop cargo slinging schemes if:
the cargo does not have special devices (loops, pins, eyelets, etc.) for slinging;
the load is equipped with a special device for slinging, but cannot be lifted with its help;
the cargo consists of machine parts and components moved by cranes during installation, dismantling or repair.
Rice. 5.3. Pipe slinging:
a - end grips; 6 — two-loop slings with a sleeve; c - beam traverse; g - pincer grip; d - towel slings; e - ring sling for a noose; g - two-loop slings (package of pipes); 1 — spacer
If there are no developed slinging schemes, then the lifting of the load must be carried out in the presence and under the guidance of the person responsible for safe production works with cranes.
Rice. 5.4. Slinging of rolled metal:
a - single load; b - package of sheet steel; c - coils of wire; g - package of I-beams; d — package of sheet steel (the grips are positioned symmetrically relative to the center of gravity of the package at a distance of 1/3 of the length from the edge); e - eccentric clamping devices; 1 - clamp; 2 — mounting bracket; 3 - spacer.
Load slinging diagrams should be posted at work sites or handed over to slingers or crane operators.
When developing cargo slinging schemes, it is necessary to observe following rules:
· the hooks of the slings must fit freely into the mouth of the loop, axle, eye or other load-handling device on the load (see Fig. 1.8);
· hooks must be wound with inside products towards their center of gravity;
· products must be attached to all hinges (trunnions, eyes);
· the branches of the slings must have the same tension during lifting;
· the angle between the branches of the slings should not exceed 90°;
· unused ends of the sling must be strengthened so that when moving the load they do not touch objects encountered along the way;
· the sling hook inserted into the mounting loop (trunnion, eye) must not come into contact with the surface of the slinged load.
Trusses are built either directly behind upper nodes, or, if there are sling holes, using fingers inserted into these holes.
Trusses (Fig. 5.5) up to 18 m are usually trussed at two points, with a length over 18 m - at four points, or lattice-type traverses are used various designs, equipped with balancing blocks that ensure equal tension of the sling ropes during lifting.
The branches of the sling should not deviate too much from the vertical, so as not to create excessive compression in the upper chord of the truss.
Flights of stairs (Fig. 5.6) with landings are stored on edge on pads 100 x 150 mm with stops. Flights of stairs without landings or steps are laid flat on pads 200 x 150 mm and spacers 80 x 80 mm, no higher than 5 rows.
Rice. 5.5. Slinging (a) and storing trusses on metal supports (b)
Rice. 5.6. Stropovka flights of stairs during loading and unloading (a), installation (b), with an extension and forks (c) and storage of flights of stairs with landings (d) and flights of stairs without landings or steps (e):
1 - sling; 2 - extension; 3 — fork; 4 - loop; 5 - safety screw
Rice. 5.7. Semi-rigid slings for lumber
(a - long-length; b - short-length; c - round short-length; d - long-length in bags) and traverses for timber (e - short-length; f - long-length; g - stacks)
Rice. 5.8. Equipment slinging:
a — a vessel with two double-loop slings; b - valves with a two-loop sling; c — the unit with two double-loop slings; d — a cylindrical tank with two double-loop slings; d — box with two double-loop slings; e - machine parts with two double-loop slings; g - equipment in a wooden container with two double-loop slings
Slinging of timber is shown in Fig. 5.7, 5.8.
When slinging timber, conventional slings cannot fully meet the requirements for the work. When uncoupling and pulling out the slings from under the bundle, the timber rolls out.
It is more rational to use semi-rigid slings with traverses.
Grab grabs mounted on forklifts are also used.
Loads are slinged in accordance with slinging diagrams. To sling a load intended for lifting, slings are used that correspond to the weight and nature of the load being lifted, taking into account the number of branches and their angle of inclination; slings general purpose should be selected so that the angle between the branches does not exceed 90° diagonally.
15.7. Lifting devices are equipped with a brand or firmly attached metal tag indicating the number, load capacity and test date. The lifting capacity of general-purpose slings is calculated at an angle between branches of 90°, with the exception of ring and single-leg slings, the lifting capacity of which is given in a vertical position. When using ring and single-leg slings in an inclined position for slinging, it is necessary to enter a correction factor for their load-carrying capacity depending on the angle of inclination.
The coefficient is determined by the cosine of the angle alpha formed between the inclined branch of the sling and the vertical. For alpha = 15°, 30°, 45°, the coefficient is respectively equal to 0.966; 0.866; 0.707.
Example. Two ring slings, each with a lifting capacity of 5 tons, are inclined to the vertical at an angle of 45°, therefore load bearing capacity each sling will be equal to 5 tf x 0.707 = 3.535 tf.
15.8. Load-handling devices manufactured for third-party organizations, in addition to the stamp, are supplied with a passport.
15.9. On the container (boxes for solution, bunkers, containers, etc.), in addition to special technological data, its purpose, number, dead weight and carrying capacity are indicated. Safe Operation containers are produced in accordance with GOST 12.3.010-82. The container capacity must prevent the possibility of overloading the machine (crane).
For moving concrete mixture Bunkers (tubs) made in accordance with GOST 21807-76* should be used. Depending on the purpose, the container must meet the relevant regulatory requirements.
15.10. When slinging structures with sharp edges using the strapping method, it is necessary to install gaskets between the edges of the elements and the rope to protect the rope from chafing. The spacers are attached to the load or are permanently attached to the sling as inventory.
15.11. When slinging, the hooks of the slings should be directed away from the center of the load.
15.12. It is prohibited to have faulty or non-standard containers and faulty load-handling devices at the facility under construction.
15.13. When developing cargo slinging schemes, it is necessary to take into account the position of cargo during transportation by road, storage of cargo in an on-site warehouse, installation and necessary tilting.
15.14. To store load-handling devices and containers at the construction site, a special place is allocated, where slings are stored in special cabinets or chests, where precipitation does not fall, traverses are stored on special stable stands, and containers are stored on pads.
15.15. Slinging loads from stacks (rolled metal, pipes, timber, etc.) should be carried out in the following sequence:
At the most protruding end of the structure, located in the top row, a loop of a ring sling is put on, hanging on the hook of a two- or four-strand sling;
The slinger moves to a safe distance and gives the command to raise the end of the load to a height of 0.4 - 0.5 m;
The slinger approaches the raised load from the side and places wooden pads with a cross-section of 100 x 100 mm under it at a distance of 1/4 from its ends (when lifting pipes and logs, there should be stops on the pad to prevent the load from rolling out);
The slinger moves to a safe distance and gives the command to lower the load onto the linings and loosen the sling (safe distance means the distance to places that are outside the danger zone at the appropriate lifting height. These places should not be in the danger zone from the building under construction);
The slinger approaches the load and, using a metal hook (made of wire with a diameter of 6 mm), places ring slings under the load at a distance of 1/4 of the length of the load from its end, then removes the first sling, and tightens the supplied ring slings with a “noose” and puts them on the hooks two- or four-legged sling;
The slinger gives the command to lift the load to a height of 20 - 30 cm, makes sure that the sling is secure and gives the command to further move the load.
15.16. When performing loading and unloading operations at picking depots, slinging of timber laid in bulk should be done using a hydraulic grab or pincer grip.
15.17. Unslinging of structures installed in the design position should be done only after they have been permanently or securely temporarily secured.
15.18. To avoid spontaneous loss of cargo, the container is loaded 100 mm below its sides.
15.19. To install structures at height, it is necessary to use load-handling devices with remote slinging.
15.20. The main provisions for slinging are given on the load slinging diagrams included in the work project.
Question from Natalia:
Colleagues, good afternoon! I am addressing the representatives of JSC Russian Railways. Guys, maybe someone has diagrams for slinging rails, reinforced concrete. And wooden sleepers, crosspieces and other MVSP? I really need it. If there are, please share.
Reply to Natalia:
1) DIAGRAM FOR STRAPING WOODEN TRANSFER BAR
2) SCHEME FOR SLINGING WOODEN SLEEPERS
3) DIESEL ENGINE LOADING SCHEME
4) STRAPING SCHEME OF REINFORCED CONCRETE DRAINAGE TRAYS
5) STRAPING SCHEME OF REINFORCED CONCRETE FOUNDATION BLOCKS
6) SCHEME FOR SLINGING REINFORCED CONCRETE SLEEPERS
7) DIAGRAM FOR STRAPING THE COUNTER RAIL
8) STRAPING SCHEME OF THE CROSSING
9) SCHEME OF SLINGING RAILS LENGTH 25 M.
10) SCHEME OF SLINGING RAILS LENGTH 12.5 m.
11) DIAGRAM FOR SLINGING A FRAME RAIL WITH A POINT
12) SCHEME OF SLINGING RAILS LENGTH 12.5 m.
13) SCHEME OF SLINGING RAILS LENGTH 25 M.
14) SCHEME FOR SLINGING RAILS LESS THAN 12.5 m LONG.
15) STRAPING SCHEME OF A REINFORCED CONCRETE PLATE
16) SCHEME FOR SLINGING TIMBER (edged and unedged boards)
CARGO SLINGING SCHEME
In addition to the topic, you can download free instructions on labor protection when performing slinging work.
Stropovka - this is a set of methods for tying and hooking loads for their
lifting and moving by lifting machines (cranes).
The following requirements apply to slinging structures:
sling devices, their fastening to the structure being lifted and
the lifting crane must be reliable;
labor intensity and duration of slinging and unslinging operations
should be minimal;
the use of sling devices and devices must be
multiple (devices must be inventory);
unslinging should be done at a distance (without lifting
slinger to the slinging site);
slinging
exclude
violation
strength
structure, as well as its falling and overturning.
For slinging various construction loads for one-time lifting
Instead of special lifting devices, you can use ordinary ones
ropes by tying them into knots and loops. The simplest and most reliable methods
cargo strappings are given in table. 2.1.
To protect ropes from chafing when tying loads with sharp
Protective pads should be installed at the edges.
When the load is laid loosely on loop slings, its movement
(regardless of the number of loops on the sling) is allowed only if there is
elements that prevent displacement in the longitudinal direction.
When moving loads with sharp edges using rope slings,
necessary
ropes
place
gaskets,
protecting the latter from damage. Gaskets are made from
wood, cut pipe, rubber-fabric hoses, flat belts, etc.
To ensure safe operation of moving loads using cranes,
during construction, slinging schemes for transported loads are being developed, which
must be included in the PPR.
Slinging of beams and pipes is shown in Fig. 5.2, 5.3.
When unloading pipes from gondola cars and loading them onto pipe carriers
The vehicle is installed parallel to the rail track.
The crane is located between the pipe carrier and the gondola car. Safety
loading and unloading operations are largely determined by the right choice
load-handling devices.
Lifting of pipes can be carried out using end grips,
consisting of two or more ropes with hooks at the ends.
To lift long pipes, special traverses are used,
having hooks that can be fixed in different positions according to
length depending on the length of the pipes, as well as pincer grips.
Slinging of rolled metal is shown in Fig. 5.4.
Slinging diagrams, graphic representation of slinging and hooking methods
loads must be handed over to slingers and crane operators or
posted
production
Owner
the operating organization must also develop methods
tying of machine parts and machine assemblies moved by cranes during their
installation, dismantling and repair, indicating the applicable
devices, as well as methods for safely tilting loads when such
the operation is carried out using a crane.
Rice. 5.2. Slinging beams:
a - metal (in girth); b - reinforced concrete (in girth); c - metal
(traverse with pincer grips); 1 - spacer
It is especially necessary to develop cargo slinging schemes if:
the cargo does not have special devices (loops, pins, eyelets, etc.) for
slings;
the cargo is equipped with a special device for slinging, but cannot be
raised with his help;
the cargo consists of machine parts and components moved by cranes in
time of installation, dismantling or repair.
Rice. 5.3. Pipe slinging:
a - end grips; 6 - two-loop slings with a sleeve; in - beam
traverse; g - pincer grip; d - towel slings; e - ring
a lanyard for a noose; g - two-loop slings (package of pipes); 1 - spacer
If there are no developed slinging schemes, then lifting the load should
be carried out in the presence and under the direction of the person responsible for
safe work with cranes.
Rice. 5.4. Slinging of rolled metal:
a - single load; b - sheet steel package; c - coils of wire; g - package
I-beams; d - sheet steel package (the grippers are positioned symmetrically
relative to the center of gravity of the package at a distance of 1/3 of the length from the edge); e - ex-
centric clamping devices; 1 - clamp; 2 - mounting bracket; 3 -
spacer
Load slinging diagrams must be posted at production sites
work or handed over to slingers or crane operators.
When developing cargo slinging schemes, the following must be observed:
the hooks of the slings must fit freely into the throat of the loop, trunnion, eye
or other load-handling device on the load (see Fig. 1.8);
hooks must be placed from the inside of the products towards them
center of gravity;
products must be attached to all hinges (trunnions, eyes);
the branches of the slings must have the same tension during lifting;
the angle between the branches of the slings should not exceed 90°;
unused ends of the sling must be strengthened so that they
when moving the cargo did not touch those encountered on the way
objects;
the sling hook inserted into the mounting loop (trunnion, eye) must not
come into contact with the surface of the slinged load.
Trusses are slung either directly from the upper nodes, or, if available
sling holes, using fingers inserted into these holes.
Trusses (Fig. 5.5) up to 18 m are usually raftered at two points, with a length exceeding 18
m - at four points or use different lattice-type traverses
structures equipped with balancing blocks that provide
equal tension of the sling ropes during lifting.
The branches of the sling should not deviate too much from the vertical, so as not to
excessive compression was created in the upper chord of the truss.
Flights of stairs (Fig. 5.6) with landings are stored on edge on
pads 100 x 150 mm with stops. Flights of stairs without landings or
the steps are laid flat on pads 200 x 150 mm and spacers 80 x 80
mm, no higher than 5 rows.
Rice. 5.5. Slinging (a) and storing trusses on metal supports (b)
Rice. 5.6. Slinging flights of stairs during loading and unloading (a), installation (b), c
extension and forks (c) and storage of flights of stairs with
landings (d) and flights of stairs without landings or steps (e):
1 - sling; 2 - extension cord; 3 - fork; 4 - loop; 5 - safety screw
Rice. 5.7. Semi-rigid slings for lumber
(a - long-length; b - short-length; c - round short-length; d -
long-length in packages) and traverses for timber (d - short-length; e -
long; f - stacks)
Rice. 5.8. Equipment slinging:
a - a vessel with two double-loop slings; b - valves
double-loop sling; in - the unit with two double-loop
slings; g - cylindrical tank with two
double-loop slings; d - two double-loop boxes
slings; e - machine parts with two double-loop
slings; g - equipment in two wooden containers