Walther Trowal GmbH & Co. KG

Outstanding blasting results with a smart transport system
To help you get the most from continuous blasting technology, we have developed a system that sets high technical standards. The belt transport system conveys your workpieces evenly through the blasting unit, where they are continuously circulated and intensively blasted. This is an effective but sensitive way to process your workpieces.

Suitable for different workpiece shapes and sizes
The THM conveyor blasting unit is a truly universal system, which allows you to process both bulk material and complex, sensitive individual parts. You can even use it to blast thin-walled workpieces. Even the rods on the belt are adapted to your workpieces. We use polyurethane for handling sensitive parts and manganese steel for standard workpieces.

Rail system ensures quick and simple maintenance
Thanks to an innovative rail system, virtually all wear zones on your workpieces are accessible. The transport system can be easily pulled out from the unit housing. This makes it easy to quickly service your THM unit and put it back into operation.

Tailored to your needs
The THM blasting units are available in a range of configurations, specifically adjusted to your needs and the size of your workpieces. Further fine adjustments can also be made thanks to the variable processing parameters, such as the belt speed, discharge velocities and blasting medium flow rate.

To ensure the optimal result for every application we have completed our range of products with our smallest THM 300/1 and our largest THM 900/4/E.

The benefits at a glance
Processes both bulk material and individual parts with different shapes and sizes
Manual or automatic workpiece feeding
Controllable processing parameters: throughput times, discharge velocities, optional blasting medium flow rate regulation
Two turbines with 7.5 to 22 kW of power, depending on the machine type (can be upgraded to up to six turbines depending on configuration)
Special turbines for aluminium blasting medium
Easy-to-reach wear zones for quick maintenance
Customised filter systems
Wide range of loading and unloading mechanisms, such as lifting and tipping units, vibrating hoppers, rotating buffer tables and refilling systems
Belt rods made from either polyurethane or manganese steel

Parts cleaning for repair and maintenance
Important components require thorough and regular cleaning and maintenance, especially in industry, mechanical engineering and the automotive sector. Our TRT 83 x 37 cleaning trough removes grease, lubricants and other residues thoroughly and reliably, before the components are reinstalled.

Which workpieces can be cleaned?
You can use the TRT 83 x 37 cleaning trough to effortlessly clean workpieces measuring up to 80 cm in length and 30 cm in diameter. Here are some examples:

Bearing shells and covers
Engine components
Gearbox components
Shafts and axles
Labyrinth rings
Bearings, bearing units and bearing housings
TR 51 cleaning agent protects against corrosion
The trowaclean TR 51 liquid cleaning agent allows you to remove grease and other stubborn stains, whilst also protecting your components against corrosion. Unlike solvent-based cold cleaners, TR 51 is not categorised as a hazardous substance, and can therefore be used for cleaning and pre-treating surfaces for coating.

The benefits at a glance
Thorough component cleaning
trowaclean TR 51 removes grease and stubborn stains
Sound deadening lid for noise reduction
Brush cleaning set for cleaning difficult-to-reach areas

The principle
The work pieces are gently tumbling over each other in the rotating drum. The resulting intensive mixing effect evenly exposes the work pieces to the spay pattern of the spray gun at different angles – a pre-condition for an even coating thickness.

The special drum shape and the adjustable rotary speed ensure an optimum tumbling and mixing of the work pieces. The drum inclination is infinitely adjustable within a certain angle and can, thus, be precisely adjusted to different work piece shapes. The ideal angle of inclination for the various coating processes is determined by processing trials and then stored in the machine controls.

Different drum sizes for different part volumes are available. Exchanging one drum with another is easy and requires very little time. This allows adapting the Rotamat quickly to different batch sizes or coating processes. If required, the inside of the drums can be lined with a 3S-coating. In addition, the inside of the cover and the drum housing can be coated with an anti-adhesion material.

Once the coating process is completed, the drum is mechanically tilted downward for gently discharging the finished work pieces, which are now ready for the next production step.

Homogeneous application of the coating material
An automatic spraying systems evenly applies the coating material onto the work pieces gently tumbling in the rotating drum. If requested, the machines can be equipped with two spraying systems. This is advised, if work pieces must be coated sequentially with two different materials like base and topcoat or primer and cover).

The automatic spraying systems, type HVLP, used in the Rotamat coaters produce very little spray mist resulting in a minimum of overspray.

A window in the drum cover allows the operator to visually inspect the coating process. The inside of the drum is equipped with explosion protected LED lights.

Optimum temperature
During the coating process pre-heated, filtered air is injected into the rotating drum to heat the work pieces to a pre-set temperature, which is precisely adapted to different work piece types and materials as well as different coating materials. Throughout the process the work piece temperature is monitored by an IR sensor, and the inlet air temperature is adjusted as required.

This results in a highly homogeneous, evenly coated surface, creating an intensive bond between the coating material and the work piece surface. The coating material already dries during the actual spraying process. Post process drying in a separate oven is no longer required.

Repeatable coating results 
An industrial PC monitors and controls the entire process.

The integrated recipe administration stores all process parameters created for the different applications and allows quick access to the different recipes. These include, for example, work piece quantities, inlet air temperature, drum speed (RPM), spraying volume and spraying pattern of the automatic spraying system.

The result: A stable process with absolutely repeatable, perfect coating results.

The intuitive process visualization, simple operation of the touch panel and process and control functions makes working with the Rotamat very easy.

Eco-friendly operation
Each Rotamat coater is equipped with a 4-stage exhaust air filter system including a Papp labyrinth filter, a filter mat and pocket filters.

The rotating drum is sealed allowing the work pieces to be processed under a slight negative pressure. This prevents hazardous volatile materials from escaping into the environment.