Key Benefits

  • Reliable, trouble-free operation
  • Reduced rebuild and repair services
  • Eliminates costly repairs and downtime
  • Increases returns and reduces risk

World-leading field service and training in gold recovery

The Knelson brand leads the industry in gravity separation technology, as an integral component in many of the world’s sophisticated precious metal recovery circuits since 1978 when it was introduced by its founder Byron Knelson. We are the world leader in the development, design, manufacturing and supply of gravity concentration technology for the global mining and minerals processing industries., We offer expert maintenance and process training services for all aspects of gravity concentration.


We understand the importance of providing support to you during both the planning and execution of any equipment or system purchased. This includes sending skilled and experienced technicians and engineers to offer guidance and complete equipment/process operation tasks. We offer both remote and on-site support to ensure a smooth transition from commissioning to full operation.

Mechanical equipment inspection services

We will provide inspection services by highly experienced technicians specialised in gravity concentrators, who will check all aspects regarding your concentrator installation and mechanical condition. If required, our technicians will also oversee a partial disassembly of the machine to inspect internal components.

Field service

We offer detailed and hands-on support throughout the life of your gravity concentrators, thus optimising your investment. This support is available in the form of troubleshooting assistance, plant audits, testing programs, as well as consulting.


To support you in attaining the most from your gravity concentrator, we offer on-site support and training services, with highly skilled personnel.

• Mechanical maintenance training: Your technicians and staff will receive a training course by a highly qualified FLSmidth instructor who specialises in gravity concentrator technology. (Presentations in various other languages can be arranged).

• Classroom training: Within a meeting/training room environment at your site, we will supply a Knelson Concentrator Maintenance Training Course consisting of approximately 4-8 hours of an interactive PowerPoint presentation.

• Hands-on training: One of our instructors will guide your skilled personnel in a hands-on training session, with concentrator disassembly and reassembly activities agreed upon beforehand.


At FLSmidth, we make sure to routinely send quality assurance professionals to generate evaluations and make recommendations for corrective actions and preventative maintenance.

The process is easy – either you can request a visit, or we can make sure they are done at regular intervals to ensure proper equipment performance. Existing processes can be evaluated for their efficiency, and a report and presentation with recommended process improvements can be provided, including cost estimates. 

Service and training for gravity concentrators

Once you invest in an FLSmidth Knelson Gravity Concentrator, it is essential to maximise your results by having your personnel trained comprehensively and supported with our expert services, testing and audits.

Reliable, trouble-free operation

Our contract maintenance service on Knelson equipment includes a technical evaluation of preventative maintenance guidelines that can be performed by routine tasks through to complete maintenance shutdowns. Through this service, you can expect reliable, trouble-free operation throughout the life of your gravity concentrator.

Reduced rebuild and repair services

Available to you is a predictive maintenance schedule that provides your personnel with a checklist of maintenance necessities which will reduce rebuild and repair services.

The contract maintenance service is for those who are planning a shutdown and need

experts to inspect or service their gravity concentrator(s), need guaranteed repairs or servicing, are unfamiliar with significant overhaul procedures or require up-to-date training.

Eliminates costly repairs and downtime

With proper preventative maintenance at scheduled servicing intervals, significant repairs will be reduced to a planned event, putting you in control. This means the availability of your concentrator is extended, your total rebuild costs are far less than replacing your concentrator with a new one, and engineering improvements and upgrades can be incorporated into the refurbishment.

Increases returns and reduces risk

Our Minerals Testing and Research Centre (MTRC) in Salt Lake City, USA, is your single-source choice for mineralogical support services related to geo-metallurgy, leaching, E-GRG (gravity recoverable gold) testing, and characterisation of materials. We provide high-quality, cost-efficient and reliable mineralogy work, performed by a team that has decades of mining and production experience. Our QCX RoboLab can complete larger sample loads in the shortest possible time to support your geo-metallurgy-modelling and ore-profiling programs.

Global extensive after-sales service for gravity concentrators

We pride ourselves on understanding your needs once you have invested in our gravity concentrators, so we provide comprehensive after-sales services so you and your team can make the most of this world-leading piece of precious metals recovery equipment.

Plant and process support

With changing, deeper and lower-grade ore bodies, plants must continuously optimise their circuits and/or troubleshoot unexpected metallurgical problems. That effort applies to both concentrator and leaching operations.



We target our mineralogical work to optimise ore routing, blending, and forecasting of problem minerals, such as reagent consumers and/or minerals impacting gravity recovery. Surveys for gravity concentration, grinding, and flotation circuits are critical to improved processing. The FLSmidth MTRC Lab provides extensive production expertise from mining operations and mineralogical plant survey projects. We provide extensive:



  • Gravity separation / concentration testing, batch and continuous
  • Gravity circuit modelling
  • Optimise GRG recovery within the process
  • Gold deportment studies
  • Gravity gold audits
  • Intensive cyanidation testing
  • Plant de-bottlenecking, restarts and expansions




The Knelson Concentrator Maintenance Training Course in the classroom covers, but is not limited to the following topics:


  • Operation basics
  • Safety 
  • Typical operational/maintenance practices
  • Preventative maintenance
  • Maintenance schedules
  • Major maintenance
  • Bearings maintenance
  • Rotary union maintenance
  • Drive components maintenance
  • Cones and wear parts



Mechanical equipment inspections

With mechanical equipment inspections, our inspector will check all aspects

regarding the installation and mechanical condition of your FLSmidth Knelson Concentrator, including but not limited to, the following:


  • Installation
  • Machine anchoring
  • Process connections
  • Utility connections
  • Visual inspections
  • Paint condition
  • Bearings
  • Rotary union
  • Drive belts
  • Cone
  • Lubrication system
  • Piping assembly
  • Control system



Based on the inspection, our inspector will prepare a report which will include photos (if permitted by you), findings and a description of the general condition of the machine(s), and a recommendations section. Upon your request, we can provide a quote for the components that need to be replaced.

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