UNIDRILL: Kelly Bar 3 Facade Quality Control

What goes more important than the quality of your kelly bars? A kelly bar of good strength and durability makes your project safe and fast, which means, better quality with less cost!

Efficiency and safety are as important of a concern for us as for you. This is why for every kelly bar that makes it out there from our factory, we have a 3 facade quality control to make sure those values get delivered.

The 1st quality control

Roundness and straightness checking will be done before the tube gets any treatment. The bare steel tube freshly wrought and rolled will be inspected for their verticality, for the first time in their lives!

The 2nd quality control

Connecting and welding the kelly gibs onto the kelly bars is a very important step! We use 30CrMnTi for our gibs, with the hardness of 48-55HRC, while most other suppliers in the market use 20CrMnTi, which is softer. We also import the welding wire from Sweden ESAB.

The difficulty of welding gibs is that, it is an arc. We need to make it fit perfectly on the steel tube, otherwise it is not stable. Our welders with an average of over 10 years experience weld these bent or curved parts for our kelly bars, to make sure they are taken care of.

The 3rd quality control

This process happens after the tubes are connected and welded. A Full Digital Ultrasonic Flaw Detector will check the quality of the welding. Specifically, this ultrasonic detector watches out for air bubbles and crackings in the welded parts. Only after these defects are ruled out by the ultrasonic detector, can we print our UNIDRILL or UNIMATE logo onto the kelly bars and proudly claim them ours!

The article is written by Drillmaster [email protected], no one may reprint it, otherwise we will pursue the legal responsibility