METHOD STATEMENT OF DOUBLE GIRDER OVERHEAD CRANE

How to install Rail Mounted or EOT Gantry Cranes

Ohayo gozaimasu


Electrical Overhead Travelling (EOT) cranes or Gantry Cranes are commonly found in factory applications such as steel yards, paper mills or locomotive repair shops. The EOT gantry crane functions similarly to an overhead bridge crane, but has rails installed on the ground and gantry-style legs to support the crane. Capacities range from 2 to 200 tons, and sometimes even greater capacities. Most are electrically powered and painted safety yellow.

Overhead cranes, sometimes also called bridge cranes, are cranes with a hoist traveling along the bridge between parallel runways. They are designed to meet the medium to heavy industrial lifting requirements, covering all parts of manufacturing process.

With this post i just want to share knowledge for installing the overhead gantry during construction.

1.0   PLANT AND MACHINERIES

1.0     60 ton mobile crane       -  1 Nos

2.0     trailer                           -  1 Nos

3.0     20 tonne x 19m length Overhead Crane   -  4 Nos

                                    Model : CXT6062P6FO

                                    Min. Loaded Hoisting Speed = 4/0.7m/min @ 60% ED

                                    Hoist Group : Fem 3m.

                                    2 Nos girder : 9.00 Tonne ( 4.5Tonne/girder)

                                    1 nos of hoist : 2.30Tonne

                                    2 Nos end Carriages:1.17Tonne

2.0   DOULBLE GIRDER E.O.T CRANE INSTALLATION PROCEDURE (BY MOBILE CRANE)

            A. Crane Erection Inside Building

1.0   proposed indicating area required site clearance for mobile crane and trailer parking for the unloading, assembly and erection of overhead crane  (Area of 30m(length) x 20m ( width-crane span) at each bay).

2.0     Erection work will be carried out inside building.

            B.  Crane Installation

1.0          A complete double girder crane is made up the following major part:

i)                    Girders

ii)                  End carriages

iii)                Hoist

iv)                Flat cable power supply and mobile control system

v)                  Other smaller items like long travel control box, end stopper, limit switch and etc.

2.0          Upon unloading girders from trailers, the girders will be placed on stools at two ends for

subsequent crane assembly work.

3.0      Assemble end carriages to 1^st girder ( power supply side) and tigten bolts and nuts

Note: Girders and end carriages are match-made in factory with matching marks punched on each item. Re-match the matching marks during installation at site.

4.0      Strap a short sling around the girder and lift up the girder slightly by using mobile crane   

(refer Appendix A).

Note: When strapping short sling, using soft material around the girder to protect it from

being scratched.

5.0      Site touch up painting.

6.0      Tie 2 manila ropes at each of the end carriages.

7.0      Rotate the girder so that it makes an angle of approx.45º with the runway and are position in between columns.

8.0      Lift up the girder at the center until it clear the runway. Using the nylon ropes rotate the

crane from 45º to 90º ( with the runway ) ( refer to Appendix B ) and slowly lower crane

onto runway rails

9.0      Remove all ropes

10.0      Repeat step ( 4) to ( 9) for another girder

11.0      Lift up the hoist with mobile crane and place on top of girder

12.0      Fix up all electrical wiring and downshop power supply

13.0      Test each movement of the crane.

Note: Depends on the availability of power supply.

3.0                   SAFETY AND HEALTH

1.0       Regulations

All site activities shall comply strictly with UEMC Project Health and Safety Plan regulations and requirements. All staff will also be familiar with the Construction Crisis Team’s Handbook.

             2.0       Launching Safety Briefing

A safety briefing will be conducted by the launcher prior to the launching to ensure that all people involved are familiar with the works (The Designed Launcher will be fully in charge during the launching activity). The safety officer will then brief the workers on the general hazards of slab launching.

3.0       Equipment Checks

The safety officer will check and ensure that all cranes are fully operational and that there is no irregularities prior to the launching. The launching will be halted if any irregularities are observed.

4.0       General Safety

All workers are to wear PPE equipments such as  safety helmet and safety shoes within working area. All safety issues will be governed by the Health and Safety Plan and adhered to strictly.

5.0       Environment Issues

The Environmental Management Plan will be adhered to strictly on site.