It takes X60's steel as the instance,preheating temperature of pipeline steel has been got by carbon equivalent and cooling cracks the susceptible index number calculation.

The computer numerical simulation technique is used to simulate and analyze the temperature field, the thermal stress and the crack sensitivity coefficient of the ingot mold FZ25t during the solidification period of the ingot.

The weldability of TCS corrosion resistant stainless steel for railway wagon was investigated by cold cracking sensitivity test, HAZ maximum hardness test and varestraint test.

\ The sensitivity coefficients to the porosity are derived from the initial boundary value problems for the fluid equations in porous media by the Green's Reciprocity Principle.

The investigation includes such procedures as formulating a prior reservoir model, deriving sensitivity coefficients, sampling a posteriori probability density function, and predicting uncertainty of reservoir performance.

Theoretical equations for computing sensitivity coefficients of wellbore pressures to estimate the reservoir parameters in low_permeability reservoirs conditioning to non_Darcy flow data at low velocity were obtained.

The courses were arc measurement been instead of elliptic arc measurement,part\'s manufacturing errors,the non-corrected gauge probe radius and the sensitivity coefficient of the arc of small central angle.