HZP140 segment assembly bridge construction crane is specifically developed by ZZHZ and MBEC of China, featuring installing full span box girder segment, combining with the feature of prestressed concrete beam of Yellow River Bridge in Taohuayu, Henan, China. It is prevailing to use prefabricated segment assembly bridge construction crane to construct elevated highways overseas and in Hong Kong and Macao, but the construction technology above mentioned is firstly adopted in Henan, China.

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when the? crane leaves factory, usually it has a run-in period of 60 days which is regulated by manufacturers according to technical features of crane in early use time. Run-in period ensures the crane to operate normally and decrease failure rate, thus prolong its service life. At present, some users neglect the special technical demand of new machine in run-in period because of lacking of crane use common sense or tight time limit or hoping benefit as soon as possible. Some users think manufacturers are responsible for maintaining the machine in warranty period, using the machine with overload for a long time will be ok, which leads to frequent initial failure, influences the normal use of crane, shortens its service life and delays the progress of projects. So, we should pay more attention to use and maintenance of crane in run-in period.
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Lay rails of the bridge girder launcher (suggest P43 or P43 rails above)

1. Lateral sliding rail layout

2. It is unnecessary to lay longitudinal sliding rail for the bridge girder launcher, it is needed to lay lateral sliding rails for front and middle support legs, sleeper layout should be stable and reliable, use spike to fix outside rail on the sleeper, inside use spikes to buckle symmetrically with edges of two rails; cushion block is used between rail connections, outside is connected by rail splint and long bolt.

3. Lay trolley rail on the bridge girder launcher

4. Rails are directly fixed on the main longitudinal girder, rail connections are connected firmly by rail splint, set up limit switch and rail stop iron at both ends of rail.

5. Rail layout above demands smooth rail joint, correct rail distance, solid support. Distance and size should be strictly controlled to be paralleled between two lateral rails (front, middle support legs) (see table below)

Table??????? Rail Layout Requirements

 

The launching gantry crane? is of heavy bridge construction equipment, to ensure its normal work, it is necessary to operate the machine in accordance with operation instruction manual and current related rules.

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1?Application range and use of bridge girder launcher:

It is mainly used for lifting of concrete girder in bridge construction of general railway and highway.bridge girder launcher
2?Main features and advantages of product:
After researching and analyzing current highway bridge construction machine at home and abroad, combining with our successful experience, we develop and produce the new walking type bridge girder launcher according to practical situation. The main features are following:
1. First-made honeycomb girder in China with light self weight, heavy load and strong wind resistance etc.

2. The launching crane conforms to the features of construction of present bridge which form is novel and structure is reasonable.
3. the main girder and main connecting structures adopt the mature pin connecting mechanism, it is very firm and reliable, and the assembly and disassembly are rapid and convenient.
4. It doesn?t need to pave the longitudinal rails. It not only can reduce the stress of bridge, but also can save the cost of construction. It has a wide adaptability for the box girder.
5. In order to make the bridge girder launcher can adapt the longitudinal slope and transverse slope, the machine adopts legs which can move forward by it. And the force which the bridge bears should be reasonable and safe;

6. Front and middle legs can be adjusted randomly and core plate with adjustable angle which can adapt the erection of curved bridge and Slope Bridge. According to angle of Slope Bridge, the user can adjust the front and middle legs when Slope Bridge is erected. Therefore, it can be used for 45?and less than 45? any angle slope bridge
7. Transverse trolley is added to the lifting trolley, the whole machine traverses with boundary beam which resolve the problem of installation of boundary beam.

As safe operation of the launching gantry is very important in the bridge construction, ZZHZ summarizes some tips to help workers operate the bridge girder launcher smoothly, for the sake of life safety and smooth construction.
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Steel structure is the basic frame member like girder, pillar and truss, made by a connection combination of steel plate, profile steel and so on. After being transported to worksite, the steel structure will be installed and connected to be an integral structure like factory and bridge. Connection plays an important role in steel structure and will directly influence its manufacturing and installation, economical indicator and usability.
There are many connection methods for steel structure in ZZHZ, they features safe and reliable design, saving steels, simple structure, convenient fabrication and installation and so on.
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(1). Main technical parameters

Model HZQ30/80
Span （m） 30
Lifting capacity（T） 80
Total weight（T） about 105
Main girder honeycomb girder
Min curve radius（m） ≥400
Max allowable gradient（%）
longitudinal gradient≤±3%，
transverse gradient≤±4%
central distance between two girders（m） 7.0
lifting speed （m/min） 1.0
launcher longitudinal moving speed（m/min） 4.6
launcher transverse moving speed（m/min） 3.0
trolley longitudinal moving speed（m/min） 4.6
trolley transverse moving speed（m/min） 1.7
power（KW） about 75

(2). Configuration for HZQ30/80 bridge girder launcher (1 set)

item specification origin quantity remark
main girder: Steel structure ZZHZ 2 parts One side girder about 50m
Front support： Steel structure ZZHZ 1 set
Middle support： Steel structure ZZHZ 1 set
Rear bracket： Steel structure ZZHZ 1 set
Rear support： Steel structure ZZHZ 1 set
trolley： Steel structure ZZHZ 2 sets 40t×2=80t
Downstroke reducer of front support： XLED63-2.2KW China 2 sets Tapered spline brake
Downstroke reducer of middle support： XLED63-2.2KW China 2 sets Tapered spline brake
Lifting reducer： ZQ500-11KW China 2 sets Tapered spline brake
Longitudinal movement reducer of trolley： XLED63-2.2KW China 4 sets Tapered spline brake
Transverse movement reducer of trolley： XLED63-0.5KW China 4 sets Tapered spline brake
Driving hang reducer of support leg： GKF37- Y0.8-4P China 4 sets Tapered spline brake
Roller walking reducer： XLED63-2.2KW China 4 sets Tapered spline brake
Hydraulic station： ZZHZ 2 sets
Hydro-cylinder of front support： HSGK160-750 China 2 units With hydraulic lock
Hydro-cylinder of rear bracket： HSGK200-600 China 2 units With hydraulic lock
Electric element： Schneider 1 set

(3). About after-sales service

1.Quotation: USD 175,000 per set FOB Tianjin
2.Terms of payment: T/T, L/C
3.Quality warranty : 1 year quality warranty
4. Installation and commissioning
Our responsibility: We will send two technicians to guide you how to install and commission the bridge girder launcher, and they also help train your staff with free charges.
Your responsibility: you are responsible for their food and accommodation, salary and round trip tickets.
5.Time arrangement:Lead time: 65 days

(1) CALCULATION CONDITION

1） Rated lifting capacity 80t
2） Span 58.58m
3） Lifting speed 3m/min
4） Dynamic load effect coefficient as lifting loads
5） In working condition wind speed 35m/s, wind pressure
In non-working condition wind speed 46.5m/s, wind pressure1.35×103N/m2
6） Stability coefficient as crossing piers n>1.5 (in special working condition wind speed limitation 4 grade, wind speed 8m/s, wind pressure 40 N/m2)

(2) DESIGN OVERVIEW
In installing girders working conditions, irrespective of structure dead load of gantry crane for carrying girders and take into consideration simple connection between gantry crane structure and bridge girder launcher rear part but the factor is not fixed. Under the crossing pier condition, structure of gantry crane for carrying girders is connected firmly with that of the bridge girder launcher, considering the influence the gantry crane structure on the bridge girder launcher structure.

Main girder stiffness and load coefficient is designed to meet users’ demand but does not follow China Standard.

In non-working condition with rare wind and snow, add a horizontal connection system on the main girder midspan to connect two main girders together if the bridge girder launcher has a large span.

(3) LOAD CALCULATION
3.1 Rated load：PQ＝80 t
3.2 Structure dead weight load
Main girder and guide beam
PG1＝148+23=171 t
(therein main girder for gantry crane for carrying girders 20.5t)
Front support leg PG2＝3.4 t
Middle support leg PG3＝27.7×2=55.4 t
Gantry crane support legs PG4＝13 t
Trolley and sling PG5=40 t
Main girder dead load distribution rule (dead weight of per unit length)
Main girder (two sides) q＝ 2.08 t/m
3.3 Horizontal load inertial force
1) Launcher moving inertial force PHD (main girder, support legs, trolley, sling and lifting loads)
Launcher moving speed with full load 3m/min（0.05 m/s）, if starting and brake time is considered 3s, accelerated speed a=0.017 m/s2
PHD＝φ5ma =1.5 ma
Get : all parts PHD：
Main girder
PHD1 ＝1.5×148×1000×0.017=0.4 t；
Support legs
PHD2 ＝1.5×（3+48）×1000×0.017=0. 13t；
Trolley and sling (with overhead crane) PHD3＝1.5×44×1000×0.017=0.11 t；
Lifting loads PHD4＝1.5×80×1000×0.017=0.2 t；
Guide beam PHD5＝1.5×23×1000×0.017=0.059t；
Load distribution type
Inertia force of main girder and guide beam is distributed as uniform load.
Main girder (single girder)：

Guide beam (single guide beam)：
Inertial load of trolley, sling, lifting loads and support leg is distributed as concentrated load ：

2） Trolley moving inertial force PHX (trolley, sling and lifting loads)
Trolley moving speed with full load 4.6m/min (0.077m/s), if starting and brake time is considered 3s, accelerated speed a=0.026 m/s2
PHX＝φ5ma=1.5 ma
So ：PHX＝1.5×（44+80）×1000×0.026=0.5t

3.4 Horizontal lateral force as trolley moves askew.
1）Lifting object is at midspan of trolley
So R1=75t L/B=6.5/3.5=1.86
After looking up the table λ1＝0.05(L-span, B-support legs central distance)
Ps1＝0.5∑R1•λ1＝0.5×75×0.05＝ 1.875t
2）Lifting objects are nearest to the support leg
So R1=115t
Ps2＝0.5∑R1•λ1＝0.5×115×0.05＝2.9t
Therein ∑R-sum of wheel pressure of trolley brake wheel at one side, λ-horizontal lateral force coefficient

One important operating principle for HZQ59/80 launching gantry electrical system is to do a movement at one time, then next action to avoid fault, it must be followed especially at starting and stopping operation.
It is strictly prohibited to adjust the movement of other systems if one system is working, especially prohibit to rotate the change-over switch.

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