Process the datum surface parts first. Because the surface is used as the positioning datum during the machining process, so as to provide a precise datum for the subsequent processing as soon as possible.

There is too much slag or not cleaned in the molten iron , and the slag is not paid attention to when pouring.

The selection of verification tools should be selected according to the accuracy level of the inspection platform. The correct and reasonable selection of inspection tools is an important guarantee for the verification results of the inspection platform.

Graphite shedding and high carbon content will cause black rust spots, as well as uneven surface of the assembly platform, with pores, and blackening caused by spitting acid.

The shape and structure characteristics of the testing surface plates: The shape of the working surface is divided into rectangle, square or round. The working surface can be processed with V-shaped, T-shaped, U-shaped grooves, round holes, and long holes for different test work needs.

Cast iron angle plates are used for component inspection and clamping in machining. It is used to check the 90° angle of the workpiece.