Archive: Jul 2019

What is the Powder Coating Process?

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Powder coating is an extremely popular finishing method across industrial and commercial applications. This common finishing technique provides metal or plastic components with an attractive, durable coating. The finish looks similar to paint, but uses a dry powder that adheres to the substrate through electrostatic charging. While typically applied to metal, powder coating can be used on any substrate that tolerates heat and electrical grinding—two necessary components of the coating procedure.

 

How Powder Coating Works

The success of powder coating depends on two factors: the powder coating itself and the application process.

The coating powder consists of chemical agents that can be altered based upon the needs of the end application. The base is a polymer resin, but various curatives, pigments, and additives are typically added to achieve different properties. These components are ground into a fine powder, which is then applied to a substrate.

Application of powder coating requires that the substrate first be prepared in a multi-step process that allows the coating to adhere properly. The coating is evenly applied through either electrostatic spray deposition, which uses a spray gun, or fluidized bed application, in which the powder behaves like a liquid and components can be individually dipped or coated.

Powder coating offers several advantages, including:

Strong protective finish

Powder coating is not only decorative, but functional. The powder coat finish is equally attractive to paint, but more durable.

Cost-effective/environmentally friendly

Excess powder can be collected and reused, decreasing waste. Powder coating produces no harmful volatile organic compounds (VOCs), which means no additional VOC disposal expenses.

Versatile

Powder is most commonly applied to metal products, but may also be used on various plastics, fiberboard, and other materials that can withstand the process.

 

Learn About Our Powder Coating Services

 

Steps in a Typical Metal Powder Coating Process

The specific steps used in industrial powder coating procedures vary slightly depending on the method and substrate used. The process to powder coat a metal component involves the following stages:

  1. Cleaning: The cleaning process removes surface contaminants in preparation for finishing. A soak in an alkaline cleaning tank is typically sufficient to remove most dirt, grease, and oils that would otherwise interfere with adhesion.
  2. Rinsing: Proper rinsing removes the remnants of the alkaline bath. The process typically involves various stages of spraying and immersion designed to optimize water usage.
  3. Phosphating: While not strictly necessary, phosphating is often performed after rinsing to improve the metal’s finish. The technique induces a chemical reaction that results in a phosphate coating. This coating improves adhesion between the surface and the powder while also serving as an additional layer of corrosion protection.
  4. Drying: Specific drying procedures depend on part geometry. Simpler parts can be dried using infrared heating, which is less energy-intensive. Oven heating may be necessary to fully dry larger or more complex components.
  5. Powder Coating: Once these preparatory steps are completed, the powder itself can be applied. This involves charging the powder and workpiece with an electrostatic charge within a special coating booth, then spraying the powder onto the substrate.
  6. Curing: Curing typically requires high levels of heat and, like drying, can be accomplished in either a convection oven or through infrared heating. Infrared curing is particularly helpful as it is quicker and reduces the chance of defects.

Southern Spring Powder Coating

At Southern Spring and Stamping, we pride ourselves on providing a full range of manufacturing services. Powder coating is just one of the secondary services we offer to complement our metal components, offering attractive, high-quality finishes suitable for diverse applications. To learn more about our metalwork services and finishes, request a quote today.

Comparing Metal Welding Techniques: MIG Welding vs. TIG Welding

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Welding is the process of joining two metals (e.g., steel, iron, aluminum, copper) or thermoplastics together. There are many ways to weld materials, and each process uses unique tools and techniques. For instance, hyperbaric (or underwater) welders use arc welding to join materials on boats and oil pipelines, while NASA uses advanced techniques like friction stir welding to work on satellites in space.

 

Most welding jobs fall under the following categories:

  • MIG welding
  • TIG welding
  • Stick welding
  • Arc welding

Two of the most popular techniques—MIG and TIG—are used in a variety of industries to provide permanent welding to a plethora of materials.

What Is MIG Welding?

Metal inert gas (MIG) welding—also called Gas Metal Arc Welding (GMAW)—utilizes a MIG electrode wire and a specialized gun called a “MIG gun” to fuse two pieces of metal via heat. MIG guns also contain a gas bubble to prevent air from contaminating the weld.

One of the core benefits of MIG welding is the materials themselves aren’t fused together. Instead, the consumable MIG electrode is fused to both pieces of metal. This makes MIG an extremely versatile form of welding.

Here are a few details to note about this welding process:

  • Since MIG guns consume both gas and the MIG electrode, both will need to be replaced occasionally. MIG welding relies on consumables.
  • While MIG welding is one of the most popular welding methods, it’s not well suited for outdoor welding. Since gas is being dispersed to prevent air from contaminating the weld, drafts and wind can interfere with this process and introduce potential contaminants into the weld.
  • This technique is well suited to automation.
  • MIG is also one of the easiest methods for welders to learn since the gun automates many of the processes.

One of the primary reasons MIG welding is popular is that it’s incredibly easy to learn, use, and control. The MIG gun acts as the only tool, and you can start and stop each operation with the pull of a trigger.

What Is TIG Welding?

Tungsten inert gas (TIG) welding—also called Gas Tungsten Arc Welding—uses a TIG electrode and a specialized torch called a “TIG torch” to fuse two pieces of metal via heat. Unlike MIG welding, TIG does not use a consumable electrode. This means that the two pieces of metal are being fused together instead of using a filler. Like MIG welding, TIG also requires that a gas bubble be utilized to prevent weld contamination.

One core benefit of TIG welding is that the rod fed into the weld puddle is incredibly thin, so you can perform hyper-technical welds that require near-perfect aesthetics. This makes TIG extremely useful in welding situations that require incredibly clean welds—such as wires or thin parts.

Here are some more details about TIG welding to note:

  • This technique is another popular choice in automation. While it’s slower than MIG, it produces less waste.
  • TIG torches don’t use consumable electrodes, but they will still need gas replacement.
  • It is relatively slow compared to MIG welding.
  • TIG welding does not produce any splatter, which can make the welding process less messy.

The Differences Between MIG and TIG Welding

mig welding vs tig weldingWhile both MIG and TIG are used on a wide variety of metals, there are some essential differences to remember. The most crucial distinction is that MIG uses a consumable electrode that is leveraged as a welding filler. TIG, on the other hand, uses thin non-consumable rods that are applied directly to the weld puddle. This means MIG doesn’t fuse two pieces of metal together, but TIG does.

Because of this, TIG welding is well-suited to thinner materials since it needs to heat the metals enough to form a bond. MIG is an excellent choice for fusing thicker metals since it uses a filler that is heated rapidly to joint them together. For these reasons, welders often utilize both MIG and TIG welding processes to handle various aspects of parts.

Both MIG and TIG also have unique workflows. TIG welding has lower throughput since it’s slower. But, because it doesn’t consume electrodes and there is no byproduct, it can be easier to work with. MIG welding is high-speed and accurate, but it does consume electrodes and the weld isn’t as aesthetic as TIG welding on thinner parts.

Here are a few additional differences to keep in mind:

  • MIG welding can result in splatter since you use a filler material.
  • MIG welding can join two different materials together—though this is rarely advised.
  • Certain kinds of materials are better used with either TIG or MIG. It will often depend upon the electrical resistance of the material.

Contact Us for Your MIG and TIG Welding Needs

At Southern Springs, we utilize both MIG and TIG welding to create a variety of specialized parts. We recommend that you use a combination of these methods to provide the best weld and cost for your components.

We also provide high-quality sheet metal fabrication, stamping, and die processes as part of our turnkey welding solutions. Metal welding requires keen attention to detail and the ability to choose the right equipment and techniques for the right part.

Are you looking for a welder who understands these nuances and uses a strategic combination of welding methods to deliver superior results at-scale? Request a quote today.

What is the Compression Spring Manufacturing Process?

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Spring manufacturing requires an artistic touch. Manufacturers use many different techniques to create symmetrical springs that retain their ability to absorb shocks and store energy while keeping their shape over long periods of time. At Southern Spring and Stamping, we use coiling, winding, or bending processes to create high-quality springs through both manual and automated processes.

We’re experts in the compression spring manufacturing process. We specialize in a wide range of spring-manufacturing techniques that benefit a variety of applications. Here, we describe the basic spring manufacturing process to give an idea of how versatile our springs can be.

 

How We Build Springs

We build springs following three basic steps:

Coiling

First, we feed the wire through a straightening process. The straighter the wire as it enters the coiler, the better the part it will produce. In this process, preprogrammed CNC equipment adjusts the arms and arbores to manufacture the spring, fine tuning elements including the spring’s free length, pitch, and coils. As the machines produce the spring, a high-speed camera takes pictures to track the process, allowing us to measure each part and make adjustments as necessary to ensure it stays within tolerance. From here, the machine cuts the spring from its wire, and the product travels into the stress relieving process.

Stress Relieving

The coiling process subjects the wire’s material to stress, causing it to become brittle. We correct this by heating the spring in an oven, allowing the coil to form metallic bonds and settle in its new shape. The oven holds the coiled wire at an appropriate temperature for a predetermined amount of time, and then slowly allows the coil to cool.

Finishing

Once the wire exits the stress relieving process, we then subject it to a number of finishing processes depending on its intended use. Spring finishing alters the spring from its original design to a specified tool that will benefit its future application. Some of the processes that go into spring finishing include:

  • Grinding: We grind both ends of the spring to flat ends, allowing it to more easily attach to other surfaces
  • Strength peening: This process helps steel resist metal fatigue and cracking despite high use and repeated flexing
  • Setting: To permanently fix the spring’s desired length and pitch, we fully compress the spring so that all coils touch each other
  • Coating: To prevent corrosion, we either paint the spring with non-corrosive paint, dip it in liquid rubber, or plate it with another metal such as zinc or chromium
  • Packaging: We create custom packaging for springs, including bulk packaging in boxes or plastic bags

Common Spring Wire Types

We work with a number of different spring wire types, including:

compression spring wire typesMusic wire (ASTM A228)

This wire has a high carbon steel makeup, which allows it to be used in high-intensity applications such as exercise machines, lawn and garden equipment, and home-improvement tools. Music wire strings achieve minimum tensile strengths of 230–399, and they also include an elasticity modulus of 30,000 psi.

Hard drawn wire (ASTM A227)

This wire consists of medium carbon steel and forms springs that frequently appear in commercial materials like pens, office supplies, toys, and other indoor-use products. These springs vary widely in terms of their hardness, with Rockwell hardnesses ranging from C31 to C52, meaning that they can be specifically tailored to a range of different applications.

Stainless steel (ASTM A313 and ASTM A316)

Stainless steel springs come in a number of different alloys. Their rust-resistant properties render them a good spring material in medical devices, marine products, jewelry, and outdoor applications. A313 and A316 are the most common types of stainless steel springs—both include elasticity moduli of 28,000 psi, torsion moduli of 1,000,000 psi, and melting points of 550°F (288°C)—but they differ significantly in terms of corrosion and heat resistance, with ASTM A316 able to withstand more extreme conditions than A313.

Stainless steel (17-7PH ASTM A313)

This stainless steel alloy’s extremely flexible strength allows it to function well in environments with high temperatures, including industrial applications such as welding and metalworking. It can achieve a minimum tensile strength ranging between 235 and 335, and melts only at temperatures in excess of 650°F (343°C).

Chrome silicon (ASTM A401)

This high-strength steel alloy absorbs shock loads very well and can retain its properties at elevated temperatures. Cold-drawn chrome silicon strings also can withstand a wider range of temperatures than other spring types because their chemical composition allows for flexibility in terms of how it forms bonds between molecules.

Phosphor bronze (Grade A B159)

This nonferrous alloy wire conducts electricity well and resists corrosion. Commonly used in applications requiring good electrical conduction and corrosion resistance, phosphor bronze springs function well in extremely low temperatures and can achieve Rockwell harnesses exceeding B100.

Types of Springs

Springs come in a number of different varieties suited for a range of applications. Our offerings include:

Compression springs

These are the most common types of spring and appear in applications ranging from pens to car engines. Their relatively simple helical design consists of a loosely coiled wire to better absorb shocks, and manufacturers usually taper the wire at both ends for easier installation in applications. These springs compress themselves to absorb and store energy, and they only release this energy once the pressure on them leaves.

Extension springs

These attach at both ends to an application, and they act as a buffer between machine joints that compress often. Consisting of a tightly coiled design, these springs extend as pressure is exerted on either or both ends, and then compress as the application compresses, safely distributing the energy of the shock along their body. These springs commonly occur in door hinges, ceiling decorations, and a wide range of industrial machines.

Torsion springs

Like extension springs, torsion springs wind tightly and expand to account for pressure exerted at either end of the application. However, they operate at a 90° angle, with one end of the spring attaching to an element of an application that’s perpendicular to another element. Torsion springs absorb energy by twisting as they’re pushed or pulled. They commonly appear in clamping applications like clips and mousetraps.

Belleville springs

These springs differ from other spring designs in that they’re shaped like disks instead of coiled wires. Also known as washers, Belleville springs provide an additional level of fastening and shock absorption between fasteners and the objects to which they’re fastened. For example, workers position Belleville springs between the head of a bolt and the object to which the bolt’s being screwed to prevent wear and tear on both the bolt head and the bolted material when the application experiences jostling or friction.

Hope Springs Eternal at Southern Spring and Stamping

Southern Spring and Stamping offers a full range of springs and other shock-absorbing applications for a variety of purposes, creating invaluable materials for both ballpoint pens and battleships. Learn more about our services at our official website and request a free quote if you like what you see.