TPT November 2011

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2011

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rticle

Experiences gathered in the operation

of the 12¾" tube welding plant

By Frank Lagac, SMS-Meer GmbH and M Caldonazzo, Arvedi Tubi Acciaio SpA

Summary

Minimised changing times, high flexibility, superior quality and

challenging products. These were requirements of Arvedi Tubi

Acciaio for the investment in a new 12¾" ERW tube welding line for

large wall thicknesses.

The chosen supplier was SMS Meer, Germany. The following

article shows the technical details and how the expectations were

achieved. The first production results are very positive and prove

that the expectations were fulfilled.

1. Arvedi Tubi, brief survey

The core business of the Arvedi group comprises the steelmaking

industry and the processing of carbon and stainless steel products.

In 2010, steel production (hot rolled coils) amounted to approx. 2.3

million tons and consolidated turnover to approx. €1.8 billion. The

Group employs about 2,000 people.

Arvedi Tubi Acciaio is the branch which produces carbon steel

welded tubes. The factory, located in Cremona, Italy, was founded

in the early 70s and is equipped with state-of-the-art manufacturing

facilities. The company concentrates on the production of quality

and special products and has a leading position on both the

domestic and the European markets.

Arvedi Tubi Acciaio is equipped with a hot stretch reducing mill and

five lines for ERW tubes and has an annual production capacity

of 600,000 tons. The product mix comprises round tubes from

17mm to 323.9mm as well as the corresponding square and

rectangular tubes. The products are mainly used in the automotive,

petrochemical, thermal, construction and mechanical industries.

Arvedi Tubi Acciaio is the majority shareholder of Metalfer, the most

important Italian and one of the most significant

European manufacturers of cold drawn tubes

destined for the automotive and hydraulics market.

2. Customer’s expectation

In 2007 Arvedi started to plan the expansion of its

production capacity by means of a new tube welding

plant. With the new plant, Arvedi intended to increase

its product mix with respect to dimensions and

products (Figure 11: full scale and Figure 12: blue

marked area).

Arvedi planned to extend the formerly produced maximum dimension

of 168.3 x 12.7mm to 323.9 x 16.0mm. In addition, the plant was

intended to serve for the production of smaller dimensions with

larger wall thicknesses.

With the plant, Arvedi intended to focus on high-quality and special

products in the boiler pipe, line pipe, hollows for cold drawn tube

such as hydraulic cylinders and thick-walled construction pipe

ranges of both round and special section sizes.

The plant must be designed for rigid, smooth operation, and, at the

same time, meet all the demands placed on a state-of-the-art plant,

in particular

• above-average product quality

• high yield

• highest possible production flexibility

• high production speeds

• short size changing times

• high level of automation

• easy and reliable operation,

which are to be fulfilled by the plant technology.

To achieve the mentioned targets, SMS Meer was selected as the

plant supplier, in order to coordinate the plant equipment concept and

execution in close cooperation between the customer and the supplier.

3. Plant manufacturer’s implementation

concept

In order to fulfil the customer’s expectations, SMS Meer combined

existing proven equipment with completely new solutions.

A high production capacity at a maximum speed of up to 60m/min

requires adequately fast and automated units.

Figure 1:

Strip preparation and spiral strip accumulator