Norbar Case Study
Upgrading Equipment for Optimum Performance
Balancing weight, speed and accuracy in torque tools.
Alumina Refinery — the Bayer Process
The client is located in Gladstone, Queensland, operating a large scale alumina refinery that processes Australian bauxite into aluminium oxide (alumina) for the production of aluminium.
This is done using the Bayer process, a refining method that involves four main steps: digestion, clarification, precipitation, and calcination. Three units of ore are processed to produce approximately one unit of alumina.
Hard Working Process Valves
The site features numerous process valves that control the flow of product through the refining stages. These valves are opened and closed regularly, so being able to open and close them as rapidly as possible ensures the uninterrupted movement of material through the refining processes. For run down of the valve, more than 120 Nm must be applied at the highest speed possible to maximise productivity.
The valve actuation time varies depending on each valves individual servicing requirements, but on average it was taking 76 seconds to completely open and close a valve.
Routine Valve Maintenance
Periodically, routine valve grinding is carried out on the valves to make sure that they are seating properly. For this process, much higher torque values of up to 800 Nm are needed to securely seat (and subsequently unseat) the valve.
The actuating and valve grinding task was being completed using old worn tools that were past their operating life, making repairs uneconomical and prone to frequent failure. The original tools were underpowered, incapable of delivering the speed or the power needed for optimal valve actuation.
Norbar was contracted to provide an assessment and to propose a replacement tool that would perfectly balance speed and power, whilst also remaining lightweight and compact for use by a single technician.
Image: A Norbar trial tool (Norbar PneuTorque® PTM) on a process valve at the clients site for testing.
The Norbar Solution
Norbar made multiple trips to the refinery with prototypes for testing and fine-tuning. Torque measurement equipment was used to develop in-depth knowledge of the specific job requirements in order to define the ideal solution that would achieve the task, whilst also providing improvements over the old equipment in terms of speed, weight, product longevity, and ease-of-use.
Norbar proposed the PneuTorque® PTM 2000 series tool with custom modification to the gearbox to achieve the best balance of speed and torque.
By adjusting the standard gearbox ratios of the tool, Norbar was able to significantly increase the speed of the tool whilst ensuring that its final maximum torque capability did not exceed the specifications of the valve manufacturer.
The solution delivered by Norbar provided the following benefits:
Fast and Powerful — The PneuTorque® PTM is ideal for the task due to its high-speed dual air motor. In the testing phase, it was timed at just 48 seconds to completely open and close a valve, 28 seconds faster than the old tool.
Lightweight and Ergonomic — Norbar’s PTM series of Powered Pneumatic Torque Multipliers are purposely designed to be amongst the lightest and fastest on the market today.
Ongoing Servicing — A scheduled maintenance plan makes sure that the new tool will be kept in prime operating condition throughout its life. The Norbar service program includes a torque test prior to returning the tool to the customer.