Much of the concern in post casting processes centres around the health and safety of employees, but the sensible re-use of ‘unwanted’ material removed from castings is also of significant financial relevance and also enables the foundry sector to meet important environmental commitments. Dealing with these runners, risers and gatings can be a significant and costly issue and can affect productivity.
“Safety, productivity, damage – these are all important considerations in the traditional methods of undertaking the work of breaking off unwanted parts of a casting,” says Sandy MacDonald, managing director of Clansman Dynamics. Known for providing a wide range of robust finishing equipment for the global foundry sector, the company is particularly experienced in the provision of cannons designed to blast risers and gatings from castings and power breakers, which cut and handle gatings to an appropriate size that obtains efficient re-melting.
Battle ready
It is no coincidence that the term ‘cannons’ conjures up an image of a battlefield. Indeed, the ‘battle’ to eradicate all the extraneous material from castings requires armoury that can go the distance and is fit for purpose. Clansman cannons certainly meet this criteria – they are designed to last and to make the task both simple and safe. Supplied in a range of sizes they come mounted on a crane hook and are operated manually either directly or via remote pendants to allow for safer operations with the bigger units. Alternatively, for maximum flexibility and efficiency they can be mounted on a Clansman manipulator. The single-piece forged impact head design is a key part of the equation as it significantly improves reliability because it eradicates weld and bolt weaknesses. The cannons are supplied with hook attachment points, shock absorber mounted operator handles on smaller units with direct manual control, pneumatic valves and triggers, and a connection for 6bar (90psi) air. Once the material has been removed from the casting it can be taken back into the melting process for re-use thus reducing wastage.
The Clansman ethos is not to just sell machines. The company has remained in business for many decades in a continued growth phase because an emphasis is always placed on working alongside customers to improve casting design and productivity for everyone in the supply chain. This genuine understanding of customer needs and dilemmas gives a credibility to the company and highlights the deep thinking behind Clansman’s ongoing equipment design and refinement. “The pneumatically driven cannons can be used for most materials and our machines enable customers to think about how to modify castings to make the process easier,” MacDonald explains.
“In terms of our pneumatic cannons, our largest unit can remove risers in excess of 200mm diameter in ductile material. The alternative is swinging a weight from a crane. Thus, the pneumatic cannon effectively replaces a wrecking ball, providing a vast improvement on the dangerous and uncontrolled environment created by that method of removal.
“At the lower end of the spectrum, a smaller manual hammer resolves predicaments such as vibrating white finger, making its use much safer for manual handlers.” In essence, the cannons provide a reliable and predictable solution to an age-old problem in the foundry sector. MacDonald says: “The entry level cannons are a lower cost than a manipulator but offer a more sophisticated option. Other options of removal of unwanted material include things like gas oxy acetylene cutting but that creates the dilemma of adding heat which is an extra process in the casting method.”
A superpower
Another piece of equipment that serves to enhance both a foundry’s HSE credentials and also have significant financial benefit is a Clansman powerbreaker. These ‘giant scissors’ cut unwanted material and break it down into manageable sizes making it easier to re-melt, resulting in a saving of energy, time and money.
Clansman power breakers grip, bend and break the gating – basically like a pair of scissors. In common with the pneumatic cannons a range of sizes are available with breaking forces of up (225Te) and capacity of Ø120mm section, or 104mm square, for all ductile iron grades. They are particularly robust thanks to the breaking jaws being made from high strength steel castings. Extra wear resistance is achieved by hard face welding. A regenerative hydraulic circuit results in faster closing movements to maximise efficiency.
The powerbreakers are normally stand-alone units that are fed by manipulators. The powerbreaker body is mounted on flexible supports that allow the unit to move in 3-axis, thus removing any high loads generated by the loading mechanism. The manipulator driver has control of the closing/opening operation either via a foot-pedal or button on the control handle. The machines incorporate unique bearings arrangements to accommodate complex axial and radial bearing loads. Despite this, when maintenance is required, parts are easy to remove, thus reducing potential downtime.
MacDonald explains their unique role in the post casting process: “When scrap material is too small there is less air circulation, so using crushing machines often results in this problem. Our power breakers enable the material to be broken down into the appropriate size for re-use – another example of a foundry being able to save money and show sustainability.”
Back in early 2014, Betz Industries in Grand Rapids, USA was struggling with many of these issues. Betz produces very large castings in ductile iron, ranging from machine tool beds and stamping dies to wind turbine components. With large castings come large runners, risers and extraneous gating – some up to 4m long. Up until this point, Betz was paying a local scrap dealer to remove all the material, cut it up and ship it back. “It was expensive and the material was coming back rusty, which was causing issues with our electric induction furnaces. I had remembered meeting Clansman at a previous GIFA exhibition in Germany and we decided to see what was possible with their equipment,” says David Moorhead, vice-president of Betz Foundry. The requirements were big; cutting 4” square section in ductile iron. Clansman identified their PB150 as the correct powerbreaker and a successful test was organised with a German customer.
Clansman and Betz worked together to identify a layout for processing the runners/gatings and an order was placed for a C2010 manipulator to load the PB150 breaker. “The cost savings of having the material cut-up and processed in-house meant that the equipment pay-back was within the first two years. Furthermore, the material quality for re-melt was much improved and everything is done in a safe and controlled manner,” says Moorhead. Manipulator and powerbreaker continue to be an integral part of post casting processes at Betz Industries. The Clansman Dynamics website makes the claim: “you are in safe hands”. As has been highlighted here, it certainly seems so for foundry personnel around the world.
Contact: Andrew Allan, sales director, Clansman Dynamics, Tel: +44 (0) 1355 579 900, email: [email protected] web: www.clansmandynamics.com