Anyone who owns large plant equipment knows that there are numerous maintenance items that need to be carried out on a regular basis. But the little Ball Studs in your steering assembly often get overlooked amid the big ticket Engine, Tyre and Hydraulic maintenance. Yet a quick, relatively low cost 30 minute test can save days or weeks of downtime and repairs.

What you might not know is that your Ball Studs are recommended to be checked as often as twice a year. According to most Large Plant Equipment OEMs, Ball Studs need to be checked every 1000 hours or 6 months. Safety is a big concern but the risk of Ball Stud failure is far too easily overlooked by a lot of operators.


So what are we looking for?

Ball Stud Rapallo - Perth Kalgoorlie Goldfields

Ball Stud showing significant fatigue cracking

Cracks. Cracks lead to failure. The risk of letting Cracks silently propagate in a critical component should not be underestimated. Ball Studs are usually covered in grease and also a small cover. Even after taking these covers off and cleaning them up, cracks that can lead to catastrophic failure will be invisible to the naked eye. In fact the most common areas for these cracks are not even visible from the angle in which the studs are installed.

Using Ultrasonic Testing (UT), our Non Destructive Testing (NDT) technicians can identify cracks in the critical areas of the Ball Stud. This can usually be done in about 30 minutes, depending on the piece of equipment. One of the other advantages of UT is that the testing can be done without even removing the grease cap! Technicians simply complete the UT from the bottom of the Ball Stud.

Cracks are most often found in the neck of the Ball Stud. This is a concentration point of stress in the material due to the shape. Shown here is a crack in the neck of a Ball Stud which has been highlighted using Magnetic Particle Inspection (MPI). The crack was originally identified by UT while still installed.


Why all this testing?

A cracked Ball Stud is putting not only your equipment at risk but also your personnel. A catastrophic failure of a Ball Stud while the equipment is in operation could easily lead to the plant careening out of control and causing significant damage to equipment and your people. The best case scenario is significant downtime while you repair the steering assembly.

Steering components, including Ball Studs should be tested or replaced after any significant impacts involving the steering equipment.

While replacement is quicker, to save throwing out the Ball Studs, Rapallo can test the Ball Stud involved in the impact to see if it is still fit for purpose to be used as a spare.


How can Rapallo help?

Rapallo has NDT equipment and personnel in both Kalgoorlie and Perth. We have a range of NDT capabilities from UT for Ball Stud inspections through to Acoustic Emissions (AE) for condition monitoring.

Our work inspecting Ball Studs takes us to Mine Sites and plant yards all over Australia. Our NDT technicians are inducted in a myriad of sites around Western Australia so can quickly and easily perform these Inspections for you.

To save time and money we recommend our clients time these inspections when as many vehicles as possible are available for inspection back to back. This saves on Mobilisation costs and keeps your inspection periods aligned for next time.


Contact Rapallo

Need Non-Destructive Testing? Contact Rapallo’s team at and utilise our broad knowledge and experience in asset management and engineering. Want to know more about any of Rapallo’s services? Click the respective links below.

Environmental services

Plant and Machinery Inspections 

Recruitment and labour hire services   


 Non Destructive Testing



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Rapallo – Perth Office

10 Elmsfield Rd, Midvale, 6056 Western Australia

Phone us on:  (08) 6279 0900

Rapallo Goldfields – Kalgoorlie Office

10 Broadwood St, Kalgoorlie, 6430 Western Australia
Phone us on:  (08) 9021 7983 or (08) 9021 8399
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