Given the crucial nature of the medical and healthcare industry, it is only proper that the tools as well as devices that are commonly found in the operating room or those necessarily chosen to be surgically implanted in a patient’s body must be made from the highest caliber of material.
Such is the reason why stainless steel is predominantly used in the medical and healthcare industry and why it is the primary material chosen to undergo centerless grinding processes or operations to acquire the right shape as well as tolerances of the necessary tools, instruments, and storage devices.
However, the question remains unanswered as to the reason why stainless steel is the primary choice of material to be utilized in the creation of instruments, tools, and devices in the medical industry. In today’s post, we’re taking an in-depth check and read-through about surgical grade steel and its common steel variations: 316L and 316 stainless steel, as well as, other factors that influence its wide usage in the medical industry.
Read on to fully satisfy your curiosities about the stainless steel as well as the processes and operations it undergoes which allows it to be flexibly utilized in the medical and healthcare industry.
What are Stainless Steels?
Stainless steels are iron-based alloys which mainly contain amounts of chromium and carbon but may also contain various amounts of other metals like nickel, titanium, and copper.
Out from the other major types of steel, stainless steel is one of the most well-known steel materials due to its robustness when it comes to resisting corrosion especially in environments prone to exposure to high concentration of acids and other chemical solutions. As such, its ability to robustly resist corrosion is mainly due to its chromium content and the higher it is, the better is its resistance.
However, its strong capability to resist corrosion is not the only thing that makes it popular. As a matter of fact, it also has the ability to withstand extreme temperatures and proves to be versatile in industries that operate in extreme temperature environments.
Furthermore, this type of steel has a shiny and easy to clean surface which makes it a perfect material when it comes to tubing and storage, perfectly useful and appropriate in the medical industry.
With such stellar features, it is no wonder that stainless steel is mainly used and made to undergo centerless grinding and other machining operations for the creation of tools, instruments, and storage devices in the medical and healthcare industry.
However, one should be aware of the fact that stainless steel has a lot of variations and the one particularly preferred in the medical industry are the Austenitic stainless steel, 316L and 316 Stainless Steel grade and the Martensitic stainless steel, 440 and 420 Stainless Steel grades.
In this article, we will only focus mainly with the Austenitic stainless or commonly known as the “Surgical Grade Steel” as Martensitic stainless steel is mostly used in creating cutleries.
What Is a Surgical Grade Steel?
Under the Austenitic stainless steel metal comes the three most popular grades: 304, 316-L, and 316 Stainless Steel metals which are considered to be of medical grade or commonly known as surgical grade steel.
Yet, one wonders how the surgical grade steel got its name and how it originated?
In truth, there is no formal definition for this type of stainless steel grade however, countless literature has unanimously implied that these stainless steel grades are the ones commonly used in the manufacture of medical devices, tools for surgical and non-surgical operations, and as biomedical implants in the medical and healthcare industry thus deriving its nomenclature.
However, it is important to note that not all grades of stainless steel can be classified as that of a surgical grade. This is necessary to remember since there are varieties of stainless steel and that not all of it can be used as a biomedical implant as some of the steel grades may cause allergic reactions to the patient and works the best only as a cutting tool, as a needle, or be molded into as a storage device.
As such the most commonly used stainless steel variation for implants is the 316L stainless steel which is a low-carbon version of the 316 Stainless Steel hence the ‘L’ on its nomenclature.
According to the book written by JB Park which is, “Biomaterials Science and Engineering”, the 316L austenitic stainless steel is commonly recommended for surgical implants as its lower carbon content allows for a better resistance to corrosion especially with chlorine-bearing solutions such as that of the physiological saline content of our bodies. Its improved resistance to corrosion makes it a far more cost-effective implant material.
Moreover, comparing 316L and 316 Stainless Steel grade shows that its low-carbon counterpart is also a better choice when it comes to welding and an easier material that can work with centerless grinding machines.
Nevertheless, other Austenitic stainless steel grades and the Martensitic ones are all still widely used in the medical and healthcare field not as implants but as tools, devices, or as storage containers which proves the flexibility of the stainless steel usage in the said industry.
Surgical Grade Steel and the Centerless Grinding Process
Injection needles, surgical suction tubes, clamps, forceps, and even hospital bed handrails as well as IV poles are all made from stainless steel yet little is said as to how it came to be. All of these essential tools and devices are shaped through abrasive grinding processes out from the appropriate surgical grade steel through centered, centerless grinding, and other applicable grinding processes.
These essential tools, instruments, and devices do not automatically spring up on their own and get its precise shape rather, the raw materials which are the 316L and 316 stainless steel are processed into the abrasive grinding machines bearing in mind the proper tolerances and finishes.
However, to ensure superior quality to said needless, suction tubes, biomedical implants, and even IV poles, quality raw materials are not the only things that need to be secured. It is also important that medical and healthcare facilities must secure medical tools and devices from suppliers with the best grinding and machining operations.
Securing such a crucial step is necessary but often neglected which is why it is important to recognize and highlight its importance. Without the right grinding machines to do the centerless grinding and other precision grinding operations, these tools and drills will not become efficient devices within the industry.
The necessity of the role played by the grinding processes is so downplayed that it’s time to provide an avenue for people to know how important it is in producing the top-quality medical tools and equipment.
To illustrate, let us put into picture catheter dilator rods as well as lancets which are common stainless steel surgical instruments you find in the operating room. These surgical grade steel instruments must achieve not only the necessary finishes but also the required thickness and tolerances. To do so, stainless steel raw materials need to undergo the proper through feed or centerless grinding machine to produce the required high-quality surgical tool or device. Plus, the proper grinding machine must also be used depending on the steel variation to be processed whether it is 316L or 316 stainless steel considering the difference of ease of machining between the two.
It is in such note where one can say, having the 316L or 316 stainless steel is not enough rather such high quality material must still undergo the proper centerless grinding or other abrasive grinding process to achieve the required high-quality shape or tolerances from it.
The Final Word
With all that has been said and done about stainless steel as well as its common variations: 316L and 316 stainless steel, it is understandable why it is widely used in the medical and healthcare industry. With its stellar features such as robust resistance when it comes to corrosion, excellent capability to withstand high temperatures, as well as its easy-to-clean surface; it is no wonder this material is predominantly utilized in the creation of medical tools, instruments, and storage devices.
However, it is also an eye-opener for everyone that although the choice of raw material for the manufacturing or creation of medical tools or instruments is important, one must not discount the contribution of the grinding process used may it be centered, through feed, or centerless grinding process and the grinding machines to be utilized of which such surgical grade steel material must undergo.
It is in such juncture that one must realize, both the surgical grade steel material, whether 316L or 316 stainless steel be used, and the appropriate grinding process, whether centered, through-feed or centerless grinding, are both essential to achieve and acquire a high-quality medical tool, device, or instrument.
One cannot stand alone without the other and therefore, must be used hand-in-hand to efficiently achieve the desired quality for the tools, instruments, and storage devices required and necessary in the medical and healthcare industry.