Mechanical grab

Grab mechanical structure itself is not configured to open and close, usually driven by a rope or rod force, operating characteristics can be divided by double rope grab and single-rope grab, the most commonly used is the double rope grab.
Two rope grab opening and closing of supporting rope rope around the supporting bodies, respectively opening and closing mechanism of the roll. Figure 1 is a double rope grab the working process: a support rope and rope while opening and closing down, open the mouth into the bucket stockpile. b is the tightening of the opening and closing rope grab jaws closed and materials. c is the support rope grab is closed and the opening and closing rope simultaneously rise. d is the support rope does not move, opening and closing abseiling, bucket mouth open and remove the materials. Double rope grab, electrics tacker  easy to operate, high productivity, widely used. Using two sets of double rope after a four rope grab, work processes and the same double rope grab.
Support single rope grab ropes and opening and closing with a rope with a rope. The rope through a special locking device for opening and closing alternately supportive role. Grab the single rope winding mechanism is relatively simple, but the production is low, a large number of loading and unloading operations rarely used.
Grab crawled under the bulk density of the material is divided into light (such as crawling cereals), medium (such as crawling grit) and heavy (such as crawl iron ore) Class 3; divided by the number of double jaw jaw grab and multi-jaw grab, the most commonly used is a double jaw grab. For the bulk ore, iron and steel scrap, and should adopt more jaw grab, because it has more than claws, sharp cut features, easy to insert stockpile, can get better crawl results. There is also a structural principle of imitation scissors scissor grab, grab it with the force and energy of the closed jaws gradually increases, reaches a maximum in the closed end; their bucket mouth opening and the area of cover material than generally grab for the big, improved ability to crawl, help clean the yard and cabins, but for bulk materials because of its initial gripping force is small, less effective.

Grab crane classification

Grab bucket by about two or more combinations of jaw opening and closing crawl and unloading bulk material spreader, composed of a plurality of jaw gripper grab is also called.

Classified by shape
Can be divided according to the shape and orange petal shell-shaped grab grab, the former consists of two full buckets, the latter having three or more of the jaw plates.
Classification by drive
Press the drive can be divided into mechanical and hydraulic grab grab two categories.
A hydraulic grab
Hand pallet jacks grab itself with the opening and closing structure, generally with hydraulic cylinders driven by a plurality of hydraulic jaw plates, also called hydraulic claw grab. Hydraulic grab the hydraulic class-specific equipment used widely, such as hydraulic excavators, hydraulic lifting tower.
Hydraulic grab products are hydraulic structures, by a hydraulic cylinder, bucket (jaw), connecting column, bucket ear plate, earmuffs bucket, bucket teeth, adapters and other parts composition, so welding is the most critical hydraulic grab production process, welding quality directly affects the structural strength and hydraulic grab life. Another hydraulic cylinder is the most critical drive components.
Hydraulic grab is a special industry equipment, accessories, need special equipment to high-efficiency, high-quality work performed, such as: CNC plasma cutting machine, beveling edge milling machine, bending machine, welding positioner machine, boring machine, hydraulic test stand, etc. .
Special hydraulic excavator grab divided into two kinds of rotating and non-rotating, do not turn back to grab excavator bucket cylinder oil used without addition of hydraulic valve block and piping; grab to be added back to the turn of the a hydraulic valve block and piping to control.
Special hydraulic excavator grab applicable occasions:
1, building foundation pit excavation pit excavation and mud, sand, coal, gravel loading.
2, is particularly suitable for trench or the side of the restricted space excavation and loading.
3, for ships, trains, car handling.

wind cable rope initial tension

powered palle ttruck is not working when the mast rope cable pre-tension force of the wind. Rally Rally beginning to take work for 15% -20%.
2 wind cable pulling rope work
Work force is at work mast cranes, wind cable rope assumed loads.
In the right wind cable wire process layout, there is always a wind cable hoisting rope is determined by the vertical axis and the mast vertical plane, this root wind cable wire called the "main wind cable rope."
3 wind cable rope selected basic principles: all wind cable wire rope shall be selected according to the main wind cable.
Selection for wind cable wire to the main cable tension and wind the rope work and as the basis of the initial tension.
(Three) types of anchors, anchor calculations
Type: Full buried, half buried, activity type and use of buildings
1 full Buried ground anchors can withstand greater tension, suitable for heavy lifting. Calculate the intensity normally be based on soil conditions and checking its horizontal beam material stability, vertical stability and beam intensity.
2 movable anchor to withstand the force is not suitable for renovation and expansion project. Calculate the strength necessary to calculate the horizontal and vertical stability stability

Herringbone pull lever pull lever forward tilt when lifting

Herringbone pull rod
Herringbone pull rod is normally provided by two logs or two steel wire rope lashing or iron pieces hinged together. The advantage is that the lateral stability than the one-man pull rod is good, the use of a small number of wind cable rope, but the component after lifting a small range of activities. Herringbone pull rod bottom with rod or rope to balance the horizontal thrust, two angle is generally about 30 °. Herringbone pull lever pull lever forward tilt when lifting, there are two wind cable in the back rope. To ensure that when lifting the bottom of the pull rod firmly, pull the lever in a bottom mounted a guide pulley, lifting cable connected to the winch through it, and then the other on a rope connected to the anchor.
Roundwood herringbone pull rods, from the weight of 40 ~ 140kN, pull rod length 6 ~ 13m, roundwood small diameter 200 ~ 340mm; steel herringbone pull rods, from the weight of 100kN, pull rod length 20m, pipe diameter 273mm, wall thickness 10mm; starting weight 200kN, pull rod length 16.7m, pipe diameter 325mm, thickness 10mm.
(Three) cantilever pull rod
Pull lever arm pull rod in the middle-man or 2/3 of the height of the boom from a device. It is characterized by a lifting height and lifting larger radius, boom scissor pallet truck angle is also large. But this crane lifting capacity is small, light elements used for lifting. Boom can be mounted on the derrick, derrick pulling a lever.
Edit this paragraph mast crane is required to use non-standard cranes, generally used by the site constraints, the other can not be lifting cranes occasions.
(A) the basic structure of the mast crane and classification
Mast crane structures: the mast body, lifting systems, stability systems, power systems
Mast Body: mast base and accessories.
Mast form of the structure is divided into lattice and solid abdominal (usually steel) cranes.
Lifting system consists of pulleys, steering wheel and rope and other components.
Stabilization system including wind cable ropes, anchors, etc.
Power system is mainly electric winch, there are hydraulic devices.
(Two) wind cable rope pull rope wind calculation and the choice of cable
Wind cable wire is mast crane stability system, related to the safety of the crane, affecting mast axial force. Wind cable rope pull into the work force and the initial tension.

is the most simple lifting equipment

Mast Crane ----- fixed mounted cranes, generally used for port terminal mast crane, also known as pull rod or the rod, is the most simple lifting equipment. General use wood or steel production.

Chinese name: English name Mast Crane: mast crane Definition: from the main mast, boom and winch composed of fixed jib cranes. Applied science: Water Science & Technology (a subject); hydraulic engineering (two subjects); Construction Machinery (Water) (two subjects)
Introduction Mast Crane
Mast Crane ----- fixed mounted cranes, generally used for port terminal mast crane, also known as pull rod or the rod, is the most simple lifting equipment. General use wood or steel Hand pallet jacks  Such cranes with making simple, easy assembly and disassembly, lifting capacity, limited by the characteristics of small construction site. Especially large components but the lack of large lifting crane, the type of lifting equipment even more its superiority. But such cranes need to set up more wind cable rope, difficult to move. In addition, the lifting radius, poor flexibility. Thus, mast cranes generally used for heavier elements, hoisting more concentrated, narrow construction site, but the lack of other suitable when large lifting machinery.
Edit this paragraph structure (a) one-man pull rod
SOLOS pull rod is divided into: Wood-man pull rod, steel rods and pull one-man one-man pull rod lattice.
SOLOS pull rod by pulling rods, lifting pulley, winch, anchor rope and wind cable and other components. Number of wind cable wire which is generally 6 to 12, at least not less than 4. Lifting the pull bar holding not more than 10 °, inclination. Striga pull lever is moved by its bottom skid proceed. (One-man pull rod erected)
Wood-man pull rod from the weight in less than 100kN, lifting height is 8 ~ 15m; steel pull rod weight of up to one-man 300kN, lifting height of 20m or less; lattice-man pull rod weight of up to 1000kN , lifting height of up to 70m.

after the start of the inspection engine

Turn power key to turn a file in a clockwise or press the start button , the starter motor and the diesel engine flywheel starter gear that meshes starting gear , driven engine starts running . Each starter continuous working time must not exceed 15s.

(2) the best time to start successfully , such as making the second start, twice starting interval scissor pallet truck be greater than 1min, not yet in stationary diesel engines and starter before the start button , in order to avoid severe impact damage parts. When the engine starts running , you should immediately release the start button or electric keys, avoid to damage the gears.

3 When the engine can not be started several times in succession , the response to such diesel fuel system or starter checks , troubleshooting doing start.

Second, after the start of the inspection engine

1 after starting the engine should be at low speed , check the meter indication is normal, listen to any abnormal sound , and make the necessary adjustments.

(2) Check for oil spills, leaks , leak, leakage, if necessary, tighten or repair.

3 Diesel preheated to 50 ℃, the instrument is working properly before starting or after crane hydraulic pump and PTO shaft combined until the hydraulic oil temperature reaches above 30 ℃ , can the lifting operation .

Third, the diesel engine running

1 engine after starting , you should first low-speed operation for some time, so that the engine warm-up , after the instrument is working properly , that should stop the continued low-speed operation , enter the artificial state. Low speed diesel engine , oil pressure should not be less than 1000kpa. Special attention should be : diesel should run at low speed for a long time , because the engine crankshaft speed lower than the rated speed, the fuel injector atomization will deteriorate over time, will lead diesel engine does not operate properly ; Secondly , prolonged low-speed operation will the lubricant viscosity , oil pump oil pump running slow cause insufficient , leading to poor lubrication of the bearing parts of the bearing alloy occurs off the block and other accidents , and low speed diesel engine work is not stable, easy to produce shock loads .

(2) When the engine temperature rises above 50 ℃ , the diesel engine can perform normal operation . Normal working temperature is best controlled at 80-90 ℃. Oil pressure should be between 300-400kpa .

3 diesel engine operation is prohibited battery master switch is turned off , you can not have abnormal sound or noises .

Long Feng small crane lifting characteristics and classification

Long peak years of independent research and development of small crane crane favorite of consumers, according to the type of crane can be divided into: bridge type (bridge cranes, gantry cranes small), cable type, jib (self-propelled, tower cranes, gantry, rail, floating, mast cranes, etc.).
According to the different types of cranes lifting its characteristics are also differences, such as the following in a small self-propelled cranes, mast small crane to analyze its characteristics:
scissor pallet truck-propelled small crane small crane into self-propelled truck-mounted, crawler and wheeled into three categories, which are characterized by lifting capacity, mobility, and you can easily transfer venue for a wide range, but the roads, site requirements more high, high class fee station and amplitude low utilization rate. For single large and medium-sized equipment, lifting components.
Mast Mast small crane small crane belongs to a non-standard cranes can be divided into one-man style, herringbone style, gantry and boom-style four categories. Its structure is simple, lifting capacity, less demanding on the site, the use of low cost, but the efficiency is not high. Each time you use need to re-design calculations. Mainly applies to certain special weight, particularly high and venues receive special lifting.
Select the appropriate type of crane, hoist features need to master and working principle, with the lifting operation completed successfully