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A good solution - tungsten carbide tools pave the way for the new gas pipeline in Yemen

The Republic of Yemen is in the south west of the Arabian Peninsula. The country, which is approximately one and a half times the size of Germany, is bordered by Oman to the East, the Gulf of Aden to the South, the Red Sea to the West and Saudi Arabia to the North. The climate is dry and hot, with daytime temperatures of over 400C. Steppes, semi-deserts and desert areas dominate the landscape with stone of volcanic origin, sand and gravel areas and limestone.
The region survives on petroleum and natural gas deposits and salt and limestone quarrying.
In 2007 an unusual milling project brought BETEK Service to Yemen - a new 250km long gas pipeline from a port in the Gulf of Aden in the direction of the capital Sanaa was constructed, as part of the expansion of Yemen's infrastructure.
The gas pipeline had to be laid underground for safety reasons. This meant that a trench of 2.5 metres deep and 1.4 metres wide had to be cut selectively in the rocky areas.
The project is already underway but the construction project team had to tackle various geological problems. Progress in cutting trenches using special machines was very slow because of the change from pure sand to stone - a mix of varied, sometimes sharp-edged rock of up to half a metre thick, consisting of gneiss, granite and quartz, integrated into the sediment mass. 6.5 metres of forward movement per hour was definitely too slow. The tools used for cutting did not provide anything like the level of performance required, because the tool holders became clogged up with the cut material immediately upon use and the tools stopped rotating, which resulted in wear and frequent interruptions in the project to carry out servicing work. The fixing elements that were used to keep the tools in the holders also became distorted within a short time and some were even torn off so that it was virtually impossible to change the worn tools.
Manufacturer BETEK was called in and came up with tungsten carbide tools especially adapted for this purpose so the tool problems could be solved quickly.
The special cutting chain that was used for selective cutting of the unpredictable "stone cocktail" and for the harder stone areas was fitted with two different types of BETEK cutting tools from the BKF round shank bits construction range. The slightly stronger type was installed on the outside edge of the cutting chain, where the strain on the tools was extreme because of the high proportion of stone.
The fixing elements were exchanged as well as the tools and BETEK had the perfect solution there too with the type S35/22.

Changing the tungsten carbide tools to the BETEK brand doubled tool lifetime right from the very first on-site test by Ulrich Krämer from the BETEK Service Team. The special tool geometry means that the tool holders no longer became clogged up with material and the milling bits remained able to rotate, greatly reducing wear. The special ring attachments for the tools - supplied along with the appropriate BETEK changing tool type BZ 25 - also made handling easier during tool changes so that the project team could make better progress than before. After the persuasive tests the special cutters were converted to BETEK tools and safety rings and the partial step of the project was able to be completed twice as fast, to the satisfaction of the team and the client.

BETEK is one of the world's leading manufacturer of tungsten carbide mounted special tools for road building, mining and tunnel building, civil engineering, recycling, abrasive wear protection and many other applications. BETEK's main office is in Aichhalden near Schramberg in the Black Forest. More information at: www.betek.de