The Process of Making Seamless Tubes: an illustration of the factors to consider when selecting a reliable supplier

The process for making seamless tubes in a steel making facility, in one design, starts from heating a solid billet/round of predetermined diameter and length. It is then rolled through a “piercing mill” which basically consists of two rolls (one on top of the other) and a piercer bar (a round bar with a pointed tip in the front of it) on the outlet side of the mill.  From the name, one may assume the starting holefor the tube is created by piercing/ forcing the billet/round onto the bar and thus creating a cavity, but, interestingly, that is not so.

The conversion from a solid billet to one with a hole inside is obtained by rolling the billet between two non cylindrical, but angularly profiled rolls. The piercer bar has another function and, although close to the rolls,is not the part that ultimately“makes the hole”.

A pair of brothers, long time ago, while being very observant, realized that whenever the bearings/bushings on another kind of a rolling mill became excessively worn(causing misalignment between two cylindrical rolls), the billet started to shear in the middle (forming a cavity).

From the time of observing the result of misaligned rolls, a lot more had to happen to arrive at the present day, computer controlled piercing mills. In these mills, the sensors detect the arrival of pre-heated round. The pair of over 3,000hp motorsis accelerated to predetermined rolling speedsand thus turnthe precisely contoured rolls, under predetermined hydraulic pressure, to receive and roll over the incoming round. Besides all that, a lot more is also happening but, less than 30 seconds later, all is clear and a new hot round is on its way to start the cycle all over again. Of course, that is not the ending, but only the starting point in what is required to produce a commercially available product, commonly referred to as a seamless tube.

An “old timer” with very little schooling (less than grade 4) when questioned how he knew so much and could remember so much: “The ones who go to school/university can find it in the books. If I don’t remember it, it is not available for me” (But there was also more to that, he had to rely on his own observations, and be sure they were correct – as they were not tested or proven until he found out for himself through repeated occasions).

One supervisor to a subordinate: “The only one who does not make mistakes is the one who does not do anything”. Another supervisor’s comment: “I don’t care how many mistakes you make as long as you don’t repeat any of them”.

While it is good to have employees who through years have been observant, learned from their mistakes, accumulated, recorded and shared the information; organizations also need employees who have “learned from books”, from scientific sources, or who, as a team, have sufficient, applicable multi-disciplined knowledge to tackle new issues without always having to make mistakes first.

If it was left to some unique individuals, with or without formal education, we would not have totally computer controlled mills that inside of less than 30 second rolling timescan monitor, control and decide whether all is normal or require a production stoppage once the billet has been rolled, once the current series is completed or immediately (without waiting for the completion of the present piece in the mill, i.e. emergency stop with 3,000 hp motors (and others) at full speed).

While the above, condensed illustration, reflected a bit about seamless tube production, it does not really matter what the end product is; it takes team work from a group where some may not had much formal education to others with very specialized technical and learned knowledge. The more previous years of operation the firm has, perhaps it is safe to assume the more proficient they become. Of course the atmosphere within the company has to be conducive to sharing the expertise of each, be it through the ones with experience and/or the ones with higher level of formal education. The closer the group is as a team, in one physical location, again, the better the results one can expect to have.

For someone looking for a reliable, consistently good supplier, one may want to evaluate how the potential supplier company fairs on having a “team” that consists of sufficient and appropriate disciplines and can repeatedly produce the product they are interested in obtaining.

As an integrated manufacturer with casting (foundry) and fabricating facilitiesWabi Iron & Steel Corp. has a healthy balance of employees with formal education and a depth of standing employees, many of whom have over 25 years of service.

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