The stress loop of the working stand refers to the neutral line of the elastic deformation section of the stressed part in the short stress rolling mill after the rolling force is applied. The length of the stress loop is the sum of the length of the stressed part in the rolling mill. The elastic deformations produced by the stressed parts in the stand are proportional to its cross-section area and inversely proportional to its length. The shorter the stress loops in the stand, the smaller the elastic deformations produced, the greater the stiffness of the mill (see the stiffness coefficient of the rolling mill) and the higher the accuracy of the rolled products.

　　There are two ways to shorten the stress loop of rolling mill: one is to change the form of bearing structure of rolling mill, that is, to reduce the number of load-bearing parts in the stand of rolling mill, such as non-archway mill, to shorten the stress loop by shortening the length of the stressed parts; the other is to change the transmission path of force, such as making the rolling force not act directly above the archway window, but act on the column close to the rolling mill, so as to make the stress loop shorten. The stress loop is shortened. Comparisons of stress lines between general rolling mill and short stress line rolling mill.

　　Short stress rolling mill is mainly used for reforming horizontal rolling mill, developing double double short stress line mill (see double double short stress line finishing mill) and researching vertical short stress line rolling mill, which is built on the continuous rolling line with alternate arrangement of flat and vertical.

　　The advantages of short stress rolling mill are as follows: (1) The high stiffness of the mill ensures the high precision of the product and is easy to realize negative deviation rolling. (2) Symmetrical adjustment can be achieved. It is of great significance for stabilizing operation, improving operation rate, saving time of overhaul and replacement of guide beams, reducing operation accidents, avoiding process accidents such as elbow, impact and roll winding, and improving service life of guide. (3) Because the rolling mill has changed the way of force transmission and changed the concentrated load of screw screw to the distributed load on both sides of bearing seat, the bearing and bearing seat have better stress condition, and the bearing life has been increased by more than 1.5 times than that of common rolling mill, thus the cost of products has been reduced. (4) The roll system of this kind of rolling mill is pre-installed and adjusted before changing rolls, and the new roll system can be replaced about 10 minutes after stopping. The new roll system can be rolled over one or two steels to ensure that the product is qualified. Therefore, the rolling mill has good presetting performance, fast roll change and high yield.