How to prevent the seamless steel tube partial wall too much

Seamless steel pipe steelproduction in China in recent years the proportion of more and more big, because of its extensive use, the quality also put forward higher requirements, including seamless steel tube wall thickness deviation is one of the important indexes of its quality. Wall thickness deviation will directly affect the use of the seamless steel tube, the increasingly fierce market competition in the current, if a manufacturer can't make articles in terms of quality, produce high quality seamless steel tube, the loss of many market share is inevitable.

The author through years of practice, and some with domestic manufacturers for a large number of technical communication and practical changes, making seamless steel tube wall thickness deviation got obvious improvement. This article will comment on some of the problems involved in this paper.

In the actual production process, generally exist the following problems:

1. During the process of punch hole deviation.

2. Equipment manufacturing accuracy and structure

3. Line equipment installation and adjustment

4. The tube billet heating process

5. The tube billet

6. The influence of precision tools

7. Using automatic pipe mill

 Seamless steel pipe according to the different production methods can be divided into hot rolling pipe, cold rolled, cold drawn tubes, extruded tube, etc.

 1.1, hot-rolled seamless pipe in automatic rolling units on production. Solid billet through inspection and clear the surface defects, cut into the required length, centering on tube wear Kong Duan end face, and then sent to a heating furnace, punched on the punch. In perforated revolve and progress at the same time, under the action of roll and head, tube billet internal cavity formed gradually, according to the capillary. And sent to the pipe rolling machine automatically continue rolling. Finally approved by reeling mill all the whole wall thickness, the sizing sizing machine, to meet the specification requirements. Hot rolled seamless steel tube production by continuous rolling pipe unit is a more advanced method.

1.2, if you would get a smaller size and better quality seamless tube, must adopt the method of cold rolling, cold drawing or both combined. Cold rolling is usually conducted on two-high rolling mill, steel pipe in variable cross section round hole groove and motionless conical head of rolling in the annular groove. Cold drawing usually in 0.5 ~ 100 t single or double chain chain cold drawing machine.

1.3, extrusion method, the heating tube billet in airtight extrusion cylinder, perforated rods and extrusion, extrusion from smaller extrusion die. This method can produce smaller diameter of steel pipe.