Luer fittings are used extensively in medical and life sciences applications. But there is a tremendous amount of confusion about what these fittings really are. The” Luer Taper” is named after Hermann Wülfing Luer who was a German instrument maker working in France on the development of tapered glass bottle stoppers, and glass syringes. The result of his research and development was a conical 6% taper that produces a quick tight sealing connection between male and female mating surfaces. Mostly relegated today to the antique stores and museums are the glass stopper apothecary bottles of old, but his design is still as useful and relevant today as it was in the late 1800s. At its most basic level, a Luer fitting is defined as a small-bore, friction based, leak-proof connector. Its prominent use is to connect tubing and equipment for the transfer of fluids and gases.
Currently there are two categories or types of Luer fittings in use. The slip Luer based on the original design, and the Luer lock based on a design improvement made by Fairleigh S. Dickinson in the early 1900s. Mr. Dickinson working on what would become the “Becton-Dickinson Yale Luer-Lok Glass Syringe” added a twist-lock mechanism to hold the hypodermic needle safely in place. It was a simple way to attach and to remove a needle from a glass syringe, minimizing the danger of the needle slipping off the tip while in use, as well as reducing the breakage of the syringe tip. The male and female slip Luer fittings, as the name implies, simply slip together to form a seal. Luer lock fittings have the addition of interlocking threads to hold the connection together. The male Luer lock has an external housing with internal threads, while the female Luer lock has the addition of an external thread added at the base of the taper. These threads draw the two fittings together, tightening the seal, while providing a mechanical attachment for the two elements of the connection. The result is a secure leak-proof connection that can be easily taken apart by untwisting the two fittings to disengage the threads.
Luer fittings form the nucleus of an extremely versatile family of connectors. They are widely used in laboratories, medical devices and intervention therapies. Some examples are gas chromatography, cell research, intravenous catheters, feeding tubes, ventilators, and the common hypodermic syringe. Luer fitting are available in a variety of materials and configurations. Materials such as nylon, polycarbonate, polypropylene, PEEK and stainless steel are readily available. Both male and female Luer taper fittings can readily configured to work with threaded connections, fractional barb fittings, and ultra small tubing such as Tygon®Microbore tubing.
In summary, the term Luer represents a type of connection rather than a brand or manufacturer. The fitting consists of a 6% conical taper that precisely mates to its male and female counterpart forming a tight, leak-proof, connection that can easily be disconnected when desired. They are available in a variety of materials and configurations making them extremely versatile for use in a myriad of applications. While primarily used in the life sciences, they may be the perfect fitting for your next project.
By Mark Maffett
Looking at our product offering it is easy to see we are “heavy” in the area of tubing and fluid handling components. Within the world of tubing products we supply a lot of hypodermic tubing. I wanted to put together the reasons why this is the case because some of them may help buyers and users make good purchasing decisions, and at the same time I get to brag a little about what we have done here at Component Supply Company.
We have work very hard to offer the largest selection available of hypodermic tubing in stock with no minimum order quantity. On top of that, we can issue a material certificate for our tubing, even one 30 inch length, and ship it out the same day. This makes us unique from all other suppliers of hypodermic tubing. There are places you can purchase very small quantities; but not many and they are typically expensive, and I am not familiar with any that will, or can, provide a material certificate with chemical composition. Material certificates are not uncommon for certain suppliers, however. There are usually just large quantity requirements for purchase and shipping an order out the same day is not common for these companies. This is what makes us different from other suppliers on both the small quantity and production quantity side. If I had to sum it up, it would be that we provide material certs. for customers needing small quantities and we can ship production quantity orders the same day.
Our tag line is “The R&D Hardware Store”. We believe this is true, but it is a little deceiving. It is true in the sense that we do supply small quantities to researchers and product developers. However, it implies that is all we supply. In actuality, we supply large quantity hypodermic tubing orders at very competitive prices to hundreds of companies. We also custom fabricate parts by precision cutting, beveling and bending hypodermic tubing as well as produce custom needles. We handle this material so much on a daily basis that we have been able to listen to our customers to find out what is important and develop efficiencies so we can meet the expectations of both the R&D and production user of hypodermic tubes.
Whether you decide to use Component Supply as your hypodermic tubing supplier or not, keep these things in mind. If you need a small quantity and a material certificate, make sure the supplier is able to provide one and understands the difference between a material certificate and a certificate of conformance. If you are purchasing larger volumes find out what the turnaround time would be for the quantity you are looking for. All in all, most of the companies that supply hypodermic tubing are good companies. We are obviously proud of the services we can offer and the unique role Component Supply plays but, as you look around, you will find good quality and good service throughout this industry. That being said, we hope you still choose us.
We get calls every day with engineers and researchers looking to replace some nylon mesh or filtration screening in an application or apparatus. Unfortunately many users do not know what size mesh they actually have and some do not know if it is nylon mesh or polyester mesh. Determining the material is more difficult and the specific application can narrow that down. But determining the size is the challenge. Our mesh is monofilament woven mesh with a plain weave. We won’t get into this, but this is typically what you will find. When someone wants to know the size of the mesh, they are typically referring to the opening size. This is the size of the opening that will determine what will pass through and what will be filtered out. It would be nice to just measure this, but 100 microns is right at 0.004″ so measuring with any real degree of accuracy is not a suitable course of action.
Enter the “mesh count”. The mesh count is basically the number of threads, or openings, per inch. While this can still be challenging, the trick here is to realize that you will never get it exactly right. for example, if you count 50 threads in 1/2 inch it would be safe to double that to get a thread count of 100. The reason is that when you go to our chart you will find coma mesh sizes with a mesh count close to 100, but you will typically not find an exact match. That is ok, you are just trying to narrow it down. This exercise will narrow your search down to probably less than six sizes. Also remember that a sheet of standard copy paper is about 100 microns thick, so 10 to 20 microns one way or another will not impact most applications. If your application has specific sizes and is it critical to match what you are currently using, please contact us and let us work with you to determine the size nylon mesh.
How Big/Small is a Micron?