Pictrues
Application rangehide/show
Honeycomb girder launching gantry is specially designed for general highway and railway bridge construction. With unique and reliable honeycomb girder structure, the launching gantry allows air current to pass through the honeycomb hole as it works high above the ground, thus greatly reduce wind impact on main girder, quite safe.
Main features and advantageshide/show
◆ The first domestic creating isosceles triangle honeycomb beam, it has many advantages, such as light weight, high stiffness, low deflection, and high wind-resistance.
◆ Unique steel pin connection, which is not only firm, but also easy to install.
◆ Flexible steel legs, convenient to disasemble and transfer.
◆ The frequency-converter can be installed according to the user’s requirements.
◆ The span can be within 60 meters , the height of hoisting is under 20 meters, the weight of hoisting is under 200 tons per hoist.
◆ It is widely used in highway、 harbor and railway construction.
Main technical parametershide/show
| Item/ Data /Model |
HZQ50-160B |
HZQ40-100B |
HZQ35-80B |
HZQ30-60B |
| Max Span |
50m |
40m |
35m |
30m |
| Lifting Capacity |
160t |
100t |
80t |
60t |
| Lifting Speed of Trolley |
0.8m/min |
0.8m/min |
0.8m/min |
0.8m/min |
| Moving Speed of Trolley |
4.5m/min |
4.5m/min |
4.5m/min |
4.5m/min |
| Moving Speed of Gantry |
2.7m/min |
2.7m/min |
2.7m/min |
2.7m/min |
| Loading Capacity for Concrete Girder |
80t×2 |
50t×2 |
40t×2 |
30t×2 |
| Speed of Heavy Load |
4-8M/min |
4-8M/min |
4-8M/min |
4-8M/min |
| Speed of Empty Load |
18M/min |
18M/min |
18M/min |
18M/min |
| Max Angle of Skew Bridge |
45° |
45° |
45° |
45° |
| Min Allowed Radius for Curved Bridge |
R350 |
R300 |
R300 |
R300 |
The design basis of producthide/show
We design the launching gantry according to the rules of the newest machinery and crane in China, the rules are following:
《Cranes–Test code and procedures》 GB5905
《Safety regulations for hoisting machinery》 GB6067
《Code for design of steel structures》 GB50017
《Safety technology specification for special equipment》 TSG Q7002、Q0002
《Code for construction and acceptance of steel structure》GB50205
《Standard for quality inspection and evaluation of steel structure engineering》 GB50221
《Weld Outer Dimensions for Steel Construction》GB10854
《Code for construction and acceptance of electric equipment installation engineering》 GB232
《General technical requirements of assembly》 JB/ZQ400.9
《Mechanical properties of fasteners》 GB3098
Main requirements of designhide/show
◆ Technical index；
Safety factor 1.5
Using grade： U3
Load state： moderate
Working grade of the whole machine： A3
Working grade of the mechanism：M4
Working condition and requirements of design etc.
◆ Calculation analysis and check-calculation of the whole structure According to technology condition of design of crane, we confirm the construction condition, and then calculate and analyze the strength, stiffness and stability.
After the classical calculation, we start the calculating work of design of steel structure, and adopt the finite element analysis, the load applied to models respectively, and then calculating and analyzing beam element and plate element. Finally, the authoritative department will check and calculate again.
Main mechanical manufacturing technologyhide/show
There are many mechanical manufacturing (machinery-building) technologies; the rules of management are following:
◆ Firstly, the technology department reviews the drawing from manufacturability.
◆ Drawing up the technology guide book and making procedure qualification.
◆ Making welding procedure card, mechanical manufacturing card, assembly process, camber drawing of box girder according to drawing , rules and criterion ; emphasizing the size of welding angle, geometry size and requirements of assembly etc.
◆ Designing the assembly technology clamp according to the requirements of drawing.
◆ Making the finishing time of manufacture and patrolling card according to the requirements of drawing; controlling the quality of manufacture strictly.
quality control of manufacturing processhide/show
Technology file drawing and project are handed to production department which assorts with related department and quality department to process, manufacture, control, check and accept of product.
The workshops do the following work according to drawing:
◆ blanking splicing（technology and requirements of blanking splicing）
b.assembling welding（welding procedure card, welding technology qualification and welding record）
c.mechanical manufacture（mechanical manufacturing card）
◆ finishing time of manufacture and patrolling card
◆ Assembly（assembly technology）
◆ checking descriptive chart（controlling the geometry size and key part）.
Tracing data and leaving factory data of producthide/show
◆ The tracing data of product is made up of contract, review file, drawing , calculation book of design, specification, installation project, raw material quality certificate, product quality inspection record, welding inspection report and purchased certificate.
◆ leaving factory data is made up specification, installation project, certificate and receiving report etc.
The method and steps of installationhide/show
The launching gantry (launching crane) is the heavy duty hoisting equipment which requires very high safety. A little negligence maybe causes serious accident, therefore, the installation of launching gantry must be directed or installed by professional works, and the steps are following:
◆ surveying positioning
◆ paving rails
◆ assemble two sides main girder symmetrically.
◆ installing front and rear connecting frame
◆ installing front, middle and rear legs
◆ installing lifting trolley and auxiliary trolley
◆ hydraulic system, electrical system, operating platform and plug in power
◆ test run and commissioning.
Checking methods after installation of producthide/show
We should check geometry size, verticality, horizontality and deflection etc. after the structures are installed completely:
● Checking connecting parts connect firmly or not.
● Checking the electric connection is correct and limit switch is reliable or not.
● Checking parts of hydraulic system leak oil or not and the lifting is good or not.
● Checking mechanism and structure parts run successfully or not. 9.5、checking lubricating condition of rotating parts.
● Checking the oil level meet the requirements or not ,and then making a trial run .
● After all of above checking and adjustments are finished, and making sure every part goes well, and then doing the trial run.
operating requirements and attentionhide/show
● Adjusting the height of transverse rails of front legs and middle legs when erecting girder or moving from one pier to keep main girder’s longitudinal slope≤0.5%，transverse slope≤0.5%.
● The normal working wind speed should less than 6 grade when launching gantry works in the open air ; when the wind exceed 6 grade, the launching gantry shouldn’t moving from one pier to next pier, and components should be locked; the machine can’t work in thunderstorm day and must cut off power.
● check the steel rope is broken or not, the circuitry leaks electricity or not, the brake is reliable or not, and after the reducers get enough lubricating oil and the oil lubricate the open gears, the machine start to work; the safe circle of steel rope on the drum shouldn’t less than 3;checking the surface and fixed parts after every shift of steel rope and making a specific check every 7～11 days;
● the brake system of winch is allowed to start again after it checked;
● the lifting ,longitudinal traveling and transverse traveling shouldn’t work together; the speed of lifting and translational velocity should be slowly to avoid leaning and side tumbling;
● the goods are prohibited to throw out from launching gantry strictly; it is prohibited to lift goods to pass over head strictly；it is prohibited to lift workers by hook or goods strictly；the inflammable goods are prohibited to put on the launching crane strictly;
● After the legs move to their places, plug the safe pin to prevent the hydraulic cylinder from bearing force for a long time;
● When the tubes of components are fault, the operator should cut off power immediately, and it is checked and repaired by the professional technician; the operator shouldn’t disassemble privately; when checking and repairing the machine , the technician must cut off the power.
Time and item of maintenancehide/show
After construction are finished everyday, the workers must check the following content: if the level of main longitudinal girder meets the requirements or not; the connection of bolts and pins are firm or not; the electrical wires are broken and extruded; hydraulic system is regular or not; the track joints are plain and smooth or not; the connection of position limiter of crane and trolley are firm or not; the rail clamping device is in the working position or not; bed timber is plain and stable and the size of gauge is right or not etc.
The welding lines are checked every month :：upper and down chords of main girder , web plate, vertical welding lines of legs and the welding lines of connecting frame etc. The operators should stop working when the welding lines are broken or fatigue crack. When the users find the crack by eyes, but they can’t make sure the dangerous degree, so they should use the welding inspection instrument to test and then adopt reasonable steps to deal with.
About the painting of structure which should be painted again every two years. The users should clean the primary surface by steel brush and pay attention to the welding lines before the structure are painted.
The lifting mechanism, traveling mechanism of crane and trolley, reducer of motor and steel rope of winch are lubricated and maintained according the rules of specification.
Disassembly and steps of transferring sitehide/show
The machine is disassembled according to the following steps after the erection construction is finished.
● cylinder jacks up to make the whole machine go up 250—300mm。
● 2.0m sleepers are paved to nearby middle and rear legs respectively.
● take back the cylinder of legs and the put on the transporter.
● two lifting trolley are lifted and then put on the transporter by the special gantry.
● disassembling front, middle and rear legs and front and rear connecting frame.
● disassembling the coupling pin from back to front , each beam is carried in order and then the disassembly is finished.
● when disassembling and carrying the parts, brutal work and violent collision are prohibited, special hook and lifting tools are used for lifting. Connecting bolts and pins are put in order after they disassembled to avoid disordering and losting; the disassembly and assembly of connecting plates must be in order, and they must be marked clearly before they disassembled and assembled.
HZQ Launching Gantry
ZZHZ is a professional manufacturer of hoisting machinery, the main products include all kinds of launching gantry, gantry crane which are widely used in the highway construction projects. The honeycomb girder launching gantry made by our company is welded by the honeycomb steel plate and triangular web plate. The overall shape is triangle. Compared with the box girder, it owns the characteristics of lower gravity center, light weight, safe and good wind-resistance. Compared with the truss girder, it owns wide welding contact surface and the suffered force is even. When the truss girder suffers the force, the load-bearing points are the channel steel welding points and easy to mechanical deformation. Therefore, the honeycomb girder owns the characteristics of light deflection and high rigid intensity. The connection method between the two girders is the pin-connecting. While assembling the machine, just entering the six steel pins is enough. In this way the assembly period is short. Usually it only takes a week to install the whole set of launching gantry.
This type of launching gantry made by ZZHZ has equipped with a set of center support leg and ingot beam. The machine is assembled on the road base previously and moves forward to accomplish the task through the piers. After the machine has reached the position, fix the front part as the support and dismantle the pin connection to make the rear part of machine traveling to the concrete girder yard to lift the beam. When these girders are transported to the proper position, fix them with the rail plates and bolts. The trolleys on the front part of the machine lift the concrete girder and move to the piers, place them between the two piers after finding the proper position. For the construction of the edge girder, firstly place the girder in the center position. Then move transversely the girder with the special rack and trolleys to the edge position and accomplish the erection. Because of the different project conditions, we adopt different construction methods according to the exact condition.
The other method is that assemble the machine and erect the girder on the piers directly. Assemble the rear part of machine and install the transverse rail on the ground, then hoist this part to the piers with the truck crane to erect the girder through the lateral movement. Then place the sleepers below the machine as the support device and make the rear part of the machine moving backward 8m. After assembling the front part of the machine and bridge girder erection in the same way, connect the both parts and travel longitudinal to launch and erect the following girders. If it needs to erect in the opposite direction, just replace the position of front and rear support legs to meet the demands.
With the characteristics of multi-function, high efficiency and low cost, the launching gantry integrating carrying and erecting made by ZZHZ has made a significant contribution to the national highway project construction.
