This article introduces the author how to use cable sling, height gauge together with water level to measure girder s camber of bridge crane, and expatiates the operation process in detail.

In order to solve the problem that the prefabricated camber size of main girder\'s web plate on aluminum electrolysis multifunctional unit is too big or small,resulting in climbing or gliding problem of tapping trolley and tool trolley during production.

Girder camber is a important technical condition of Pot Tending Machine(PTM),dimensions of girder camber affects directly run of tool car and Aluminum car.

Based on the study of relevant standards and literatures and the inspection practice performed on 100 cranes,some knowledge of the rigidity and arch camber of the main beam of gantry cranes is introduced,and herefrom some new ideas about the repair and design of main beams are proposed.

This article introduced the construction technology of bonded post-prestressed for a certain long-span beam,analyzed the construction difficulties and key points,and elaborated the construction process,prestress tension,tension control and measurement of inverted arch value to ensure the overall quality of the prestressed structure.

Through those technology measures some quality problems are solved as breakage in beam end, side bending, large rising value of arch, difficult control of tension and extension value and blockage of pipe and some good efficiencies are acquired.

A regression equation indicating the relation between the fabric bulging height and weight, and between the fabric weight and compactness is derived from the test and analysis of the bulging height of heavy_weight silk fabrics conducted by self_made bulge tester, thus offering data support to the design of proper weight and compactness of the fabric for bulge proofness.