Month: December 2021

How to Correct Distortion after Welding

So you've decided to learn a new skill and have taken up welding. Regardless of whether you're trying to learn how to weld for professional or artistic reasons or simply out of curiosity, you're probably already familiar with welding distortion and the frustration it causes in your work. 

Welding distortion is a problem experienced by seasoned welders and those just beginning to learn the trade. However, if you are new to the discipline, then learning how to correct these errors is a vital skill that you'll need to acquire to fix the problem when it inevitably arises - welding distortion can cause a variety of issues for a project, most notably leaving a weld structurally unsound, threatening both the aesthetic virtues and overall stability of a project. 

By reading this article, you'll learn several different methods to correct this problem and gain a critical skill for anyone who works with welding metals to have. Let us show you can combat distortions that arise during welding. 

Common Kinds of Welding Distortion

Before diving too deeply into repair methods, let's take a moment to look at some of the more common forms of distortion that occur when welding metals. Several factors contribute to these imperfections occurring during welding work - the type of metal used, the amount of residual stress that's applied, and the type and strength of restraints used on the metal can all affect the amount and type of distortion that occurs. Below are some of the more common distortions:

  • Longitudinal shrinkage: Shrinkage happening perpendicular to the weld, caused when force is applied parallel to the weld. 

  • Transverse shrinkage: Distortions that move vertically through the weld are caused by contractions running perpendicular to the weld itself. 

  • Bowing & dishing: Metal will curve when the weld is not balanced along the cross-section's neutral axis. 

  • Buckling and twisting: One of the more difficult issues to resolve, often requiring substantial time investment. This issue commonly arises in especially thin metal structures. 

  • Angular distortion: When powerful contractive force is applied to only one side of the neutral axis, the metal will bend or warp in that direction.

Welding Repair Methods

Now that we've seen some of the most common types of distortion that occur after welding and touched on the common causes of those distortions, let's go ahead and look at the primary methods used to correct these issues. 

Method #1. Hammering or Pressing

The most commonly used method for correcting distortions is hammering, or the related practice of pressing. As the name implies, this method involves bending the metal back into its original shape using direct physical force, either with a hammer or mechanical press. 

While this is the most common (and most straightforward) option for repairing deformation, it is not without disadvantages. Hammering metal into shape is time-consuming and requires the hammerer to expend a lot of force. On top of that, hammering can potentially damage the surface being fixed and may not be enough to fully fix every kind of distortion. When done correctly, pressing can avoid some of these issues, but not all. 

Method #2. Heat Straightening

Many welders favor this process. Essentially, an oxyacetylene torch is used to carefully heat the metal in the area affected by the distortion. The metal expands under heat, and once brought to the desired temperature, the natural cooling process of metal will often bring the deformed area back to a more natural, less distorted position.

It's critical that the torch be used to carefully apply only a measured amount of heat to the metal since it may undergo molecular changes if it becomes too hot. It's also necessary to remember that the metal isn't being heated in order to be reshaped - you're merely allowing the natural properties of metal as it's heated and cooled to take its course. 

Method #3. Hot Mechanical Straightening

This process is very similar to heat straightening, though not the same. Unlike the previous method, the metal must be heated all the way to the yield stress point, causing the metal to distort plastically and naturally straighten to its original position. This more intense option is better suited to severe welding distortions in metal, whereas heat straightening is better for mild imperfections. 

However, this method has disadvantages since metal at this temperature is highly unpredictable - the metal and welds might fracture, and buckles and wrinkles are possible as the metal cools. 

Method #4. Heat Working

Again similar to the last two methods, heat working is the most extreme option. Unlike heat or hot mechanical straightening, in this method, the metal must be heated past the yield stress point to the level where molecular changes occur. Once the metal reaches a glowing red color, it may be physically shaped into the desired position. As it's the most extreme choice, this method can lead to additional distortions, and the metal may crack after hot working. 

Avoiding Distortions

Perhaps the single most important step when it comes to correcting welding distortions is taking steps to ensure that they never happen in the first place! While it's impossible to fully avoid or eliminate welding distortion, the steps listed below will help to reduce its frequency and severity. 

#1. Don't Over-Weld

One of the simplest ways to reduce the frequency and severity of distortion is to simply use less metal on a joint. Getting exactly the right amount will ultimately save you time and materials. Using a convex bead and beveling on metal plates thicker than 0.25 inches (or double beveling very thick sheets) both help to reduce distortion. 

#2. Reduce Number of Welding Passes

A good rule of thumb to keep in mind is that the more weld passes you subject metal to, the more and more noticeable shrinkages you can expect to see in the final product. It's better to have fewer weld passes with a larger electrode than many passes using a smaller one. 

Liked What You've Read?

Learning a new skill, especially one as complex and potentially dangerous as welding, is never easy. We know this from years of experience in the field - if it's made of metal, we can build it. It's that same experience that drives us here at Engineered Mechanical Systems to share our expertise with anyone who may need it. If you found this article useful, don't miss out on future opportunities, and subscribe to our newsletter for more useful and vital information that you may need!

Subscribe to Our Newsletter

Tags:

What Is the Purpose of Reverse Engineering?

Engineering has come a long way over the years. The innovation and versatility of the industry have been highlighted with technological advances, leaving more room for creativity. With this comes the creation of products and processes that have never been seen before in the industry. 

Updated techniques mean innovation, but sometimes old processes and products are the more reliable option when a problem arises. Machine products and their parts rely on engineering processes that may be out-of-date. When new technologies are introduced, we need to shift our way of doing things, including how we approach existing products and processes.  

When something breaks, what do you do? You replace it. Much like any other system, engineering works in the same way. When a part or product breaks, you replace it. In engineering, however, replacing the broken component is a common process (rather than incurring costs of replacing the entire device). For older systems, processes, and products to remain intact, it is important to adopt a way of doing things that keeps those running, even when a part breaks.

Broken parts can range from new to decades old, meaning that we need to incorporate old parts into new processes by taking them apart and seeing how they work. Insert reverse engineering. Let’s take a look at what reverse engineering is as well as some of the common techniques involved in reverse engineering. 

Reverse Engineering 101

As a part of a team designing a new product, there is a lot of work and thought that goes into the design process, including how all of the parts will work together. When engineering a product or system, you’re putting it all together with the result being a product or system that is fully functional. Reverse engineering is the opposite. 

Also called back engineering, reverse engineering involves the deconstruction of a product, system, software, structure, etc. to extract design information of its components. When knowledge is limited about the components of a product and the parts that went into it or when these parts are no longer in production, we may find ourselves in a tough spot trying to repair something that is broken. Reverse engineering allows us to see the design differently. By taking everything apart, we get to see everything in the product piece-by-piece, layer-by-layer, step-by-step. 

Reverse engineering allows for you to do two things ━ In seeing how the individual parts work, we can incorporate past processes and technologies into new ones; and we can see what already exists (or did exist before something may have been discontinued). Examining products old and new from the inside out helps us to understand what already exists. This allows us to expand our engineering knowledge and capabilities with consistency. 

How Reverse Engineering Works

We know what reverse engineering is and how it can help push innovation in machine, software, system, and product building, but what are the steps taken in reverse engineering that set it apart from traditional research and engineering measures?

Information Extraction

Being knowledgeable about the product or system being reverse engineered is key. Studying its design and how its pieces fit together may involve breaking down the product into its component parts to extract more data. 

Modeling

Much like any diagram or instruction manual, the process of reverse engineering requires some type of imaging or modeling to describe each part and how it functions (or contributes to the product function as a whole). While this is relevant to the existing function of each component part, modeling and labeling each part and function allows for expansion of the original product and parts into something that is designed with new objects or systems in mind, i.e. the innovation behind reverse engineering. 

Review

Reviewing involves testing the model (as in any engineering format) to ensure it is realistic in comparison to the original/actual object, part, or system. After testing, the model can be used as a base for rebuilding the original object or part but with new and innovative techniques. 

The Purpose of Reverse Engineering 

The overall purpose of reverse engineering is to figure out how a part, object, or system works. Diving deeper, reverse engineering helps us to recreate these objects or create similar ones with new techniques or additions. Reverse engineering is often used as a cost-saving method or because the object or part is no longer in service or production (if something breaks). 

But what are some of the other practical applications of reverse engineering aside from rebuilding outdated parts and products?

Discovering Vulnerabilities

Reverse engineering can show us how parts and products work, but reverse engineering can also show us how those same parts and products don’t work. Finding faults within a part or product can be useful when it comes to the modeling and testing steps of reverse engineering. As we model and test the part or product, we may come to a fault or issue in how the part or product works. Fixing these potential issues during the modeling and testing (or research) phases will prevent these issues from occurring when the part or product has already been distributed. 

Creating Lower Costs and More Efficiency

Success is a key product of reverse engineering, and modern-day success gears towards minimizing expenses and maximizing efficiency. Success in engineering means creating a product that is effective both on the market and in how it is used. When the costs of creating a product are lower thanks to the research done during reverse engineering, that means the product can be listed on the market for a lower cost, resulting in more frequent purchasing and higher revenue. 

Bringing About Innovation

Reverse engineering gives way for innovation, whether it is in solving the problem behind a broken part or product or finding a new way of doing things. During reverse engineering, we have the opportunity to see things from a different point of view in a product or system. As we take things apart, we may find a different use for a part or a different way of rebuilding that may not have been thought of in traditional engineering or builds. This is the connection between old and new that is crucial for the future of every industry. 

Looking for More Engineering Resources?

If it's made of metal, our team at EMS can build it. Our team and technology are here to help engineers with their Custom Fabrication, close tolerance Machining, laser cutting, forming, reverse engineering, inspection, and much more. Since 1990, we have been providing Diversified and quality fabrication and Manufacturing Services to a wide variety of customers. 

Sign up for our newsletter today to learn more about custom engineering, fabrication, and production.

Subscribe to Our Newsletter

Tags:

Laser Cutting – 5 Reasons to Switch

Many owners of manufacturing spaces are considering adding laser cutting machinery to their facilities. However, they aren’t sure of the important pros and cons to consider for this still relatively recent technology. Expanding to include newer technology can potentially be daunting, and making a well-informed decision is always vital for any business that is considering purchasing potentially expensive new equipment.

Fortunately, this is our area of expertise. This article will introduce you to some of the most common and vital benefits of adding laser cutting to your manufacturing. If it’s made of metal, we can build it, and with thirty years of manufacturing under our belts, we’re here to share some of our expertise and help you to decide if laser cutting is right for you and your business!

What is Laser Cutting?

Before we get too much further, let’s look at some of the fundamental definitions and facts behind laser cutting. 

Laser cutting refers to the subtractive manufacturing process that employs a focused laser beam to cut flat-sheet materials, with the laser itself guided by a computer program that the manufacturer uses to dictate where and how the laser will be focused to cut or etch.

There are several kinds of lasers used in this process, but generally, the equipment used will fall into two categories: C02 lasers and fiber lasers. While both kinds of lasers are used for broadly the same kind of cutting and etching work, they differ in their delivery method. C02 lasers use a combination of C02 gas and a series of mirrors to aim the laser where it’s needed, whereas fiber lasers use (as the name implies) a fiber-optic cable to achieve the same goal. 

Both kinds of machinery have their uses - C02 lasers are better suited to organic materials like leather, wood, or textiles and are less suited for cutting metals. In contrast, fiber lasers are much better and more efficient at cutting materials like sheet metal, copper, or brass. While both kinds of lasers have their uses, this article will mostly focus on fiber lasering since advances in recent years have made it the cheaper and more efficient method in many ways. 

Why Switch to Laser Cutting?

Laser cutting offers a variety of advantages that make it an attractive option for a wide range of manufacturers. While it may not be appropriate for every job or industry, it is a highly versatile and popular form of modern manufacturing. If you are considering adding laser cutting capabilities to your facility, read on to learn some of the key benefits!

#1

Precision and Accuracy

As one might imagine, lasers are a highly precise and accurate method for cutting and etching! This accuracy comes from the fact that the pattern the laser is designed to cut is predetermined by the computer program that guides the machinery of the laser. This kind of manufacturing is known as Computer Numerically Controlled (CNC) manufacturing (as you may be aware, if you already employ technologies like 3D printing), and the program used to dictate the cutting allows for extreme precision with even very complex and detailed patterns. 

In addition to the overall high fidelity to original design patterns, the nature laser cutting offers other side benefits towards precision - lasering metal automatically provides a finish to a product, whereas products made with more traditional machining will require an extra finishing step. Additionally, since lasering applies less heat than traditional machinery, there is a lower chance of material becoming burned or misshapen, and material is less likely to become contaminated or accidentally marked since there’s no direct physical contact between the laser cutter and the product.

#2

Lower Cost of Maintenance and Use

While the initial investment in purchasing and setting up lasers tends to be higher than other manufacturing options, the costs for running and maintaining a laser tend to be lower in comparison.

Unlike machining, lasers can do various kinds of work without requiring the owner to purchase and swap out different custom-designed tooling, which saves on both equipment costs and lead time between different operations. Consider chemical etching, for example, which requires a relationship with chemical, acid, and wastewater treatment contractors or suppliers, as well as generating unique physical stencils for each design, which will have to be replaced after a certain number of uses.

#3

The versatility of Use and Materials

Lasers also offer a variety of functions and operations depending on the configurations in their settings. A single machine is capable of cutting, marking, etching, and engraving depending on how its computer software is set up, and all without the need for specialized fittings or physical attachments that might be required for machining. 

In addition to having a range of uses and applications, lasers can work with a wider variety of materials than many traditional manufacturing methods. From etching ID numbers into parts used in the automotive and aerospace industries to creating home decor and household products to cutting through wood, plastics, plexiglass, and more, lasers can be useful for working with essentially any material out there!

#4

Less Waste Products Produced

Similar to point number two, laser cutting tends to produce less waste compared to other manufacturing methods - indeed, lasers don’t produce any kind of waste at all and don’t require any kind of consumable other than electricity. Lasers also produce less noise “pollution” in the sense that they are much, much quieter compared to machinery, improving quality of life around the production floor!

#5

Laser Cutting is Safe!

Even though industrial lasers make use of high-powered beams capable of causing significant damage to skin or eyes, they have been designated “low-risk” due to the fact that they are fully enclosed. As long as users don’t manipulate or interfere with safety features or intentionally expose themselves to the beam, laser cutters are generally extremely safe technology to work with. Certainly, lasers are a much safer option when compared to techniques like acid etching or machining, methods which can easily cause burns, injuries or prove toxic to workers.

Conclusion

As you can see, there are many benefits to adopting laser cutting as a primary method for manufacturing products! Lasers are quieter, safer, and more efficient than most of the older forms of manufacturing and can often be used in a wider variety of materials and situations! 

At Engineered Mechanical Systems, we know manufacturing. If you’re interested in learning about other exciting opportunities and new technologies, don’t miss your chance to subscribe to our newsletter to stay abreast of all the most relevant news and information in the industry.

Subscribe to Our Newsletter

Tags: