New Medical Device Shielding Requirements and Die Casting (IEC 60601-1-2: 2014 – 4th Edition)

New Medical Device Shielding Requirements and Die Casting (IEC 60601-1-2: 2014 – 4th Edition)

Update your products to the latest IEC standard in style!

When designing any product it is always best to make sure that safety is engineered in the initial design phase to eliminate delays and extra expenses later down the production path.

Most components manufactured for the medical industry now-a-days are made from plastics. Recently the International Electrotechnical Commission (IEC), who publishes the standards for medical devices, revised their standards for shielding electronic components within medical products. The new standard (IEC 60601-1-2: 2014 – 4th Edition) now requires two levels of protection to ensure that the device will contain any electrical shock hazards and shield patients and operators from harm if one level of protection were to fail.

Many medical devices house their electronic components in plastic enclosures that need to have a metallic paint or plating applied to meet shielding requirements. With the updated IEC standards, it is possible that the metalized plastic enclosure may not provide the required shielding to meet the enhanced standards.

In contrast the die cast industry has employed similar standards for years since metal is the material of choice for both the telecom and microwave industries. The process to plate plastic is quite expensive but with die casting there is no need to plate the final product to properly shield the electronics inside. Since die cast parts are inherently shielded, and this standard is just taking effect across the industry, it would be a good idea to re-evaluate your parts as it may now be cheaper to produce them out of die cast metal instead of plastic. A&B Die Casting has helped a number of its customers in the medical device, microwave, and telecom industries create enclosures that meet any shielding requirements in the industry.

What is electrical conductivity?

Simply, electrical conductivity is the measure of how a material accommodates the transport of an electric charge.

Metal Conductivity & Resistivity

Conduction in metals follows Ohm’s law which states that current is directly proportional to the electric field applied. The law, named after German physicist Georg Ohm, appeared in 1827 in a published paper laying out how current and voltage are measured via electrical circuits. The key variable in applying Ohm’s law is a metal’s resistivity. Electrical conductivity is commonly measured by siemens per meter (S⋅m−1) and represented by the Greek letter sigma (σ). One siemens is equal to the reciprocal of one ohm.

Resistivity is the opposite of electrical conductivity. Meaning that it measures how strongly a metal opposes the flow of electric current. This is commonly measured across the opposite faces of a one-meter cube of material and described as an ohm meter (Ω⋅m). Resistivity is often represented by the Greek letter rho (ρ).

Metal electrical conductivity and resistivity standards:

Note: The resistivity of semiconductors (or metalloids) is heavily dependent on the presence of impurities in the material.

So, what does this all mean?
Die casting is a cost effective solution for shielded enclosures that meets the latest standards put forth by the IEC.

Need assistance re-evaluating your medical device parts? Let us help! Since 1945 A&B Die Casting has been offering a quality diverse range of engineering, design, custom die cast, machining, finishing, and assembly services to our clients all over the world. Contact A&B Die Casting today.

A Few Tips to Reduce Die Casting Parts Costs

A Few Tips to Reduce Die Casting Parts Costs

Die casters employ a number of techniques to maximize tool and component design while reducing per-part costs.

What are the 3 main costs associated with die casting?

1.) Die Casting Production – depending on the part complexity, the die casting setup can be very labor intensive. The process also requires melting of the die casting alloy specified.
2.) Secondary Operations – any needed deburring, machining, sanding, or hand finishing to achieve the specified part finish.
3.) Finishing – any desired painting, plating, silk screening, or engraving.

When designing and engineering a new component you need to think beyond simple metal forming and think of die casting as the total manufacturing process. Shifting thinking along those lines can drastically reduce production costs as parts are then designed to eliminate waste as well as some secondary operations.

The largest part of the total cost to die cast something is the cost of the labor involved. The actual die casting process is one of the most efficient methods to go from raw material to finished/near finished part shape, while giving the designer the opportunity to include many features into the part that may be impractical or too expensive with other manufacturing methods.

Die casting can be incredibly cost effective because one part can be designed to replace multiple components. It is also possible to incorporate other features into the casting that eliminate secondary milling, boring, reaming, and grinding operations. One die-cast part can also eliminate assemblies that incorporate swaging, riveting, screw machining, stamping, press fitting, and welding.

What other factors affect die cast costs?
•Component complexity
•Alloy
•Part tolerances specified
•Part finishing specified

How can costs be reduced further?
Die casting does not have to be expensive. A thorough design for manufacturability (DFM) review is critical. Getting the die caster involved early in the process can greatly reduce part costs down the road. Depending on part complexity, this review may include a digital fluid flow analysis to help ensure the desired part shape is optimized for the die casting process.

On top of that, additional savings come from material reduction, improved tolerances, and good part-to-part consistency.

Much like any other engineering process or build, proper planning before production will drastically reduce your costs while speeding up the actual production time.

Need assistance or want to get started on your next die cast project?
Contact A&B Die Casting today!

Die Casting Finish : Design Your Part For The Finish You Want

Die Casting Finish : Design Your Part For The Finish You Want

A die casting surface finish can provide durability, protection, and a decorative appearance. Due to the fact that there are so many different finish options that can potentially affect the performance of the final part it is best to discuss your specific application needs early in the design phase to ensure the proper finish for your product. The specific features of many designs also have an impact on the surface finish. For example: parting lines, ejector pins, and gates can affect the end result.

Generally, extra steps are required in die design, die construction, and casting production for the more exact¬ing finishes.

There are many different types of surface finishes that are available. Below is a list of the most commonly used surface finishes:
• Abrasive media blasting
• Burnishing
• Electropolishing
• Graining
• Industrial etching
• Vibratory finishing
• Plating
• Polishing
• Buffing
• Shot peening
• Painting
• Powder Coating

What finish you chose depends on what the part will be used for. Below is a general guide for selecting a finish:

With over 75 years of die casting surface finishing expertise, our engineers will evaluate your requirements to recommend the best design and finishing options. Contact A&B Die Casting today!

Die Casting and Part Geometry

Die Casting and Part Geometry

What’s the most cost effective way to cast metal parts with minimal machining?
Die casting.

Die casting allows you to create sharply defined smooth – or textured – surface metal parts from a durable range of non-ferrous metals, such as zinc, magnesium, aluminum, and an array of composite materials at high-speed and with precision. The type of metal chosen to fabricate the part determines whether it will require the hot chamber or cold chamber method to inject the metal into the die. Die casting enables the production of components with fine details like lettering, textured surfaces, and other features without the need for additional processing.

The main benefits of the die casting process include:
•High quality: Die cast parts deliver a long service life.
•High reliability: Exceptional uniformity of mass-produced parts.
•Quick production: Die cast tooling requires minimal maintenance.
•Versatile: Die casting can create virtually any size, part geometry, surface texture, or luster.
•Minimal assembly: Assembly features such as studs, drill holes, and bosses can be integrated into the mold design.

What effects die casting the most?
Part geometry.

The initial part design is crucial and determines how parts fill and cool – part geometry affects the porosity, grain structure and internal stress states. Stress concentrators, such as those found at sharp corners, are also geometry dependent and can reduce a part’s working strength. Parts whose geometry has been optimized for die-casting–in terms of filling, cooling, and ejection–will have substantially different microstructures and internal stress states than comparable machined or spin-cast parts.

Geometry planning works as an important influential tool on casting designs. Proper geometry planning will ensure time is not lost re-casting and counterbalance problems like:
•Defects
•Poor fluid life
•Shrinkage
•Solidification
•Temperature maintenance and effects
•Hot cracking
•Strength issues (compressive strength, impact strength, and tensile strength)
•Slag formation tendency

Advantages of proper geometry designs:
•It avoids defects: Reduces the need for multiple post casting quality checks, and reduces the number of rejected castings.
•Increases energy efficiency and reduces environmental impacts: an effective geometry design influences how much energy consumption is needed for cooling and lighting temperatures used in the manufacturing.
•Improves overall quality and life of the casting: with reduced defects and reduced lead-time to produce a casting, the overall quality and operational life of the casting is increased.

Our job at A&B Die Casting is to guide our customers to the best, most efficient process for their needs. With design for manufacturability in mind, we work with our customers to create features and sub-assemblies that fit into a single part while keeping the number of parts to a minimum. Through our rapid prototyping services, complete visualization of your concept is available to implement revisions if necessary before full production runs. By incorporating innovative engineering and state-of-the-art technologies, we take pride in designing and manufacturing the highest quality tools and parts at the right price.

Contact A&B Die Casting to get started on your next project today!

K-Alloy is A-OK for A&B Customers

K-Alloy is A-OK for A&B Customers

A304 (K-Alloy) was developed by Delphi in 2003 as an innovative aluminum die casting alloy that resists corrosion, but until a few years ago was only available from a smelter on the east coast. A&B Die Casting is delighted to announce that our west coast supplier is now a licensed source of K-Alloy, making access to the alloy simpler and recycling of the alloy more efficient.

K-Alloy/A304 has been tested to withstand 3,000 hours of salt spray testing with no metal loss or surface damage. Other aluminum alloys would require additional processes and/or coatings to withstand this harsh environment.

The rugged durability of K-Alloy can eliminate expensive processes such as anodizing, chromating, powder coating and painting that are designed to slow corrosion. In addition to cosmetic improvements, K-Alloy applications provide increased functional durability for aluminum cast components in harsh environments.

Originally developed to withstand extreme salt corrosion and temperatures, vibration, and shock experienced in vehicle engine electronics, K-Alloy aluminum is currently being used or being tested on products as diverse as fishing reels, outdoor lighting, furniture, water fountains, mail boxes, radios and vehicle roof racks.

Design Assistance Brings Parts Online Faster

Design Assistance Brings Parts Online Faster

Asking for design assistance early in the process saves time and costs.

Atecs, Inc., produces high-quality products and services for aerospace and energy clients worldwide. Atecs uses their 64 years of experience to provide harsh-environment solutions for engine test, aero support equipment, constructed facilities, space flight components and energy service products.

When Atecs decided to introduce a fire-resistant version of their vent damping controller, die casting was an obvious choice for a part that needed to be strong, light, and fire-resistant. Since A&B also has a long history working with manufacturing clients, Atecs engineers shared their design with A&B engineers to make sure the part would be appropriate for die casting, as well as economical to produce.

A&B engineers carefully reviewed the client’s design requirements and suggested many ways to improve the original design.

1. The part had to perform under a heavy load of 85 pounds. A&B built fixtures and testing equipment to make sure the load requirements were met.
2. Quality and finish were critical. A&B modified the design of the boss on the original part to make trimming easier and also made modifications to eliminate flash in the gears.
3. Production and tooling needed to be streamlined. The original part design would have required complex tooling. A&B was able to simplify the tooling and help the customer bring the part online faster at a reduced cost.

Overall, A&B reduced the number of secondary operations that would have been needed, which helped to reduce overall production costs. The next time you start a design project, talk to our engineering team to see how we can help you make a product that is better than you imagined.