Spinner hanger wheel blasting machine

Straaltechniek has been developing standard and customized blasting machines for various clients to meet particular needs in foundries, paint shops and the like. One of the most widely used machines for surface preparation is the spinner hanger blasting machine. This is also known as overhead conveyor or Hang rail shot blasting machine.

The spinner hanger blasting machine derives its name due to the fact that the parts undergoes abrasive blasting while spinning on a hanger. The blasting machine is equipped with abrasive blasting turbines also termed as blast wheels . This is usually offered as a inline solution for foundries, paint shops and surface treatment lines. These machines often have semi-automatic mechanism or can also be made with fully automatic blasting capabilities. Read through the following sections for more description:

The standard overhead conveyor or spinner hanger blasting machines are specially developed for cleaning the surface of a wide range of work pieces. Shot blasting or grit blasting is a metal finishing process used either for preparing the surface for further processes or as a final surface finishing method. When the surface is blasted with abrasive media at high speed inside a blast cabin, the abrasive media or also known as blast media will impart the required roughness for further deposition process or remove unnecessary impurities and make the surface clean and uniform texture/tone. The pieces to be blasted are suspended either one by one or bunch-like by means of hangers fitted to trolleys sliding along a monorail. The movement of the rail trolley is automatic from the inlet position through a conveyor system inside the blast cabin.  The operator thus can stay outside and away from the cabin.

The abrasive particles are ejected out from the GN blast Wheels at very high speeds (80 to 150 m/s) towards the parts to be blasted. During this, the hooks are continuously rotated and shifts automatically in different pre-set positions inside the blast cabin. The movement within the blast cabin is chosen so as to optimize and achieve complete blast area coverage and desired surface finish on the parts. This often involves automatic translational and rotational movements of the products within the blast cabin and hence the name Spinner hanger blast machine. After the blasting process is completed, the conveyor pulls the hanger out of the blasting chamber and the operator can carry over.

The blast cabin of the spinner hanger blasting machine is the volume in which the main blasting action occurs. The media is ejected out of the blasting wheels and impacts the products to be blasted. The cabin supports all other functional modules and is built sturdily to ensure long life.

Special high abrasion and wear resistant Austenitic manganese steel plates are used as lining on the inner surfaces of the blast cabin which offers up to three times its surface hardness during impacts without increasing the brittleness (unlike other materials which exhibits increased brittleness with increasing hardness ). This lining ensures that the particles hitting the cabin surfaces do no damage the blast cabin and offers long life time of the machine. Straaltechniek International sources its materials through trusted line of European supply chain and OEMs . Over 45 years in the industry implies that the quality of the materials are highly reliable and durable which makes Straaltechniek a natural choice for highly productive, long enduring quality workmanship.

The doors are automatically actuated to reduce the manual effort by the operators and also ensure good sealing against dust leakages. The top of the doors are provided with openings to enable transport of the products into and out of the blasting cabin. These openings have specially designed rubber flaps and sluices to ensure blockage against dust leakage.

The spinner hanger blast machine can be provided with a safety barrier in front of the machine for added personal safety. Special sensors are placed on the barrier and if a person enters the zone between the machine and the barrier, the system stops by safety override.

To access the media cleaner and the elevator top for service actions, a safety ladder and a platform is provided. These are built strictly according to EU regulations/directives for machine building with utmost attention to safety.

The patented GN Wheel turbine or blast wheel is an outcome of intensive research and development which offers jaw dropping performance specifications which no other competitor can match. These blast wheels are arranged in a carefully selected orientation to achieve full coverage on the products.

Up to 70% higher blasting efficiency, 10 times longer life expectancy of the blades and 3x longer service life of the blast wheel is something that the GN blast Wheels offers. It is also extremely suitable for blasting with angular steel abrasive media which are usually detrimental to other types of blast wheels on the market.

Due to the deep knowledge developed during the R&D phase of GN Wheels, our experts tune the area of coverage by the wheel to get the maximum benefit in terms of using less number of wheels. Along with the other benefits listed, the GN wheel offers the quickest return on investment and a long life thereafter.

Based on the shape, size , quantity, surfaces to be blasted, throughput of the product, several spinner hanger systems are offered:

1. Single monorail with Y, I or O track type with simple doors front side
2. Pass through monorail or carrousel type with double doors both side
3. Pass through monorail type with sluices

The shot blasting equipment has a system which enables the continuous recovery and the reconditioning of the grit or abrasive media from the system to reuse the blast media. Once the grit or the blast media has impacted the part surface and thus dissipated most of its kinetic energy while accomplishing the abrasive action, it is collected from the bottom of the hopper-shaped chamber and then transported via a scroll conveyor to the bucket elevator.

This elevator lifts the grit up to the cleaning unit. It consists of a vertical housing with a pulley in the elevator head and a pulley in the elevator base. An endless belt on which steel cups are mounted runs over these pulleys. These cups scoop the abrasive media in the elevator foot, transport it to the elevator head and dump the abrasive media in the outlet towards the media cleaner. To know more about the elevator system click here.

The transported abrasive from the elevator enters the abrasive media separator through a chute. Large contaminants in the blast media are stopped by a permanently installed (but removable) sieve. Subsequently, the blast media is collected behind a distribution valve and distributed as much as possible over the width of the cleaner. The blast media or the abrasive then falls like a curtain through an air stream and is thus dusted (Windsifter). The cleaned abrasive falls into the silo. The air flow takes the dust to the separate extraction (pre-separator) where it is separated and collected in a dust bag. This results in a perfectly reusable grit in the lower storage silo ready to be transported to the turbines by means of adjustable, electro pneumatic valves. To know more about our special cleaning system and variations thereof click here.

Due to the impact of the abrasive media on the products some of the abrasive breaks and along with this, due to the erosion / wear effect on the product scales, rust, etc. are released and referred to as dust. The dust extraction system “sucks” out the particles in the cabin along with the air during which the particles can find its path through the extraction vents. Specially designed baffle plates and labyrinth is incorporated to capture the lager particles. Relatively larger particles strike the baffle plate and lose their kinetic energy which eventually will fall down due to gravity. Smaller dust particles which are still air borne passes through and reaches the dust extraction system where they will be removed from the air stream by the filter cartridges.

Carefully chosen fans in the dust extractors create the necessary flow and pressure to extract dusty air from the cabin and the abrasive media separator. The dust extractor which houses specially designed baffle plate and filter cartridges to ensure that the exhaust air is clean and the dust is collected at the bottom of the dust extractor. Generally, the standard filter unit/dust extraction system has a cleaning efficiency of 99.9%. For special applications and stringent requirements, Straaltechniek closely works with the parent company Naaykens (Naaykens.com) to offer a wide spectrum of solutions.

More information about extraction system can be found here.

Clearly understanding the customer needs and thinking for the customer is the first step for Straaltechniek to offer perfect abrasive blasting solutions. A standard wheel blast machine which offers great flexibility and covers a wide range of products shapes and size may not be suitable for a particular product.

Every client is unique in terms of their factory layout, process, material handling, available infrastructure, space, foot print, integration with processes and throughput among many other factors. As a first step, Straaltechniek walks through with the client to understand their requirements clearly and helps the customers by offering most viable solutions. Some of the modified versions of the spinner hanger systems as shown below which clear gives an impression of how Straaltechnieks strives to offer the best solutions to our clients.

Over 40 years straaltechniek has been providing bespoke solutions to clients worldwide. From valued individual clients to multinational companies, from single installations to complete inline solutions for large foundries and paint shops we offer a wide spectrum of solutions based on our clients needs. Feel free to browse through our reference sections for more details.