Archive for the ‘Custom Tubing’ Category

The Progress of Biopolymers

Sunday, July 11th, 2010

For any reader who isn’t aware, most of the world’s plastic is currently made from crude oil. The process involves several steps, depending on the polymer that one is creating, but the total cost is still a fraction of the cost needed to create biopolymers of the same quality. Biopolymers are created by having a culture of bacteria consume large amounts of biomass. When the bacteria are mature, the culture is sterilized and the biopolymer is extracted directly. Many factors are now causing chemical and plastic companies to consider possible ways to reduce their reliance on crude oil, so reducing the cost of biopolymer production has become a greater priority. Since the polymer-using world cannot simply pay double or triple for things like plastic bags, plastic bottles, and plastic tubing, achieving this cost reduction is the missing critical factor to wide scale use of biopolymers.

The difference in cost between standard polymer production and biopolymer production is not caused by any one factor. Since the world uses such a large amount of plastic, existing polymer production facilities are huge, whereas biopolymers are mainly produced by small specialty groups and laboratories. Several companies are now considering the construction of large scale biopolymer factories, but they are waiting on the researchers to bring down the other areas of cost first. At present, it requires 3 times the weight in biomass to create a unit of biopolymer. This is because the bacteria being used are only able to consume certain nutrients from the biomass, leaving the rest behind as unusable waste material. Efforts are underway to find or engineer a more efficient bacteria for this task. The other side of the coin is to more effectively process the biomass such that a greater portion of it is consumable by the bacteria. Many different areas of research are currently being conducted toward this achieving this end, because labs and universities know the impact of these discoveries will be felt for centuries to come and the shorter-term breakthroughs could easily lead to a Nobel prize.

Understanding Radiopacifiers

Monday, May 17th, 2010

In many custom tubing applications, it is desirable to manufacture the components such that they can be seen with fluoroscopy or x-ray imaging. Typically this is done by blending the polymer with another material, the radiopacifier, which is chosen because it has a higher radiopacity. With many different radiopacifiers available, it is useful to understand the strengths and weaknesses of each before making a selection.

Barium Sulfate(BaSO4) – Barium Sulfate is the most commonly used radiopacifier for almost all medical applications where imaging is an issue, including catheters and other types of tubing. While BaSO4 does not have the highest level of radiopacity, it remains moderately priced compared to the alternatives. Because it is not as dense as other radiopacifiers, a high volume of barium is needed to achieve a high level of radiopacity and typically the barium begins to affect the strength of the polymer after it exceeds 20% by volume. BaS04 also tends to mix more easily with elastomers than the other alternatives.

Bismuth(Bi) – Several different bismuth salts are commonly used as radiopacifiers, all of which have a higher density than Barium Sulfate. The high density creates a higher weight-to-volume ratio, which means that the resulting polymer can be more radiopaque with a lower volume percentage of the bismuth salt. While bismuth fillers have been growing in popularity, the fact that they are much more expensive than Barium Sulfate still precludes their use for certain applications.

Tungsten(W) – Tungsten is considerably more dense than the other alternatives, providing the highest weight-to-volume ratio of any commonly used radiopacifier. Because of this, polymers made with tungsten can be extremely radiopaque without a significant change in mechanical properties. Though raw tungsten is also relatively inexpensive, its other properties ultimately make it a more expensive choice for many applications:
1. Tungsten is highly flammable
2. Tungsten is black and extremely difficult to change the color of
3. Tungsten is abrasive, causing accelerated wear on processing equipment and surface roughness in the end result

The Most Widely Used Plastic in the World

Tuesday, March 16th, 2010

With so many varieties of plastic tubing to choose from, a design engineer has many difficult choices to make when prototyping a new medical device. Of all the materials used for such applications, polyethylene most often leads the way.

Introduced to the world of manufacturing at the time of FDR, polyethylene has since made many applications easier to manage, safer for consumers(compared to earlier metal counterparts), and cost-effective enough to mass-produce.

When choosing a type of polyethylene, mechanical factors always come first, because they are the basic requirements needed for a design to function. Fortunately, polyethylene is extremely versatile and most mechanical requirements can be met with many possible formulas. Cost must also factor into the decision, as all consumer products have a price point which limits their allowable manufacturing cost. Understanding the properties of the different grades can assist a design engineer in the selection of thermoplastic materials for products that use custom plastic tubing.

LDPE(Low Density Polyethylene) – The first invented grade of polyethylene, LDPE remains the most commonly used density. In addition to being useful for plastic tubing, LDPE is also used for plastic bags, food storage, computer/car components, general purpose containers, and many other things. While it has a lower tensile strength than the higher density grades, it has a higher resilience(maximum energy per unit volume that can be elastically stored) which makes it very flexible.

HDPE(High Density Polyethylene) – While it has many of the same applications as LDPE, it is harder, more opaque, and somewhat more resistant to heat and chemicals. It is often used for outdoor scenarios where there is a large temperature range as well as containment scenarios where chemicals need to be isolated from the environment over a wide area.

LLDPE(Linear Low Density Polyethylene) – Slightly harder to process than normal LDPE, LLDPE has higher tensile strength, impact resistance and puncture resistance. Basically this means that a thinner layer of plastic can remain intact under flexibility testing. Its primary use is in flexible tubing, but it is also used for plastic wrap, toys, lids, cable coverings and more.

UHMWPE(Ultra High Molecular Weight Polyethylene) – More expensive than most other grades of polyethylene, UHMWPE has the highest impact strength of any thermoplastic presently made. It is often referred to as high performance polyethylene and is typically reserved for “unbreakable” scenarios like artificial bone replacements, bulletproof vests, etc.

VLDPE(Very Low Density Polyethylene) – Because VLDPE is characterized by even lower heat resistance than LDPE, it is often used in packaging for frozen food and ice. Some tubing and stretch wrap is also made from VLDPE and it is commonly blended with other polymers as an impact modifier.

PEX(Cross-linked High Density Polyethylene) – PEX is almost exclusively used for long-term tubing scenarios. Many thermal properties of the plastic are improved by the cross-linking process. It maintains strength at a higher temperature and reduces flow. Under low temperatures, impact resistance, tensile strength and scratch resistance are improved. Cross-linking also improves the chemical resistance.


Nylon Tubing—the other tubing material choice

Tuesday, March 16th, 2010

It’s not only plastic that leads the way in custom manufacturing tubing—nylon is just as useful and resilient.

Recognized for its tensile strength, and selected for its stability, nylon tubing has maneuvered its way into applications ranging from uses to transport vapor or liquid, for air and brake lines, or any other situation that requires flexibility and the ability to withstand repeated stresses over a long duration without negative effects.

Phew! That’s a lot to ask from nylon tubes. But regardless, the fact remains that utilizing nylon tubes in situations that will put increasing amounts of abrasion and friction on it is critical to ensure it meets the requirements of the task.

For instance, ideal for use on cooling systems, pneumatic controls, hydraulic lines and grease lines—nylon tubes-12 is less expensive to manufacture than nylon tube-11and is perfectly suited for these numerous industrial applications.

Customers who need Nylon tube-12 specify its use when they need to prevent vapor permeation, whether the nylon tubing is delivering fuel, or any other chemical liquid. This ensures that the equipment on which it is being utilized doesn’t experience failure or compromise safety.

But customers also have the option of manufacturing nylon tube-11 which is better suited for use in the food industry as it is made from materials that comply with FDA regulations.

Although this type of nylon tube is suited for other industries, such as for chemical companies, making the choice to use nylon tube-11 in use with transferring fluids whether alimentary liquids such as milk, beer or biological such as serum or blood—nylon tubes are a prime alternative to plastic.


The Places You’ll Go With Flexible Plastic Tubing

Tuesday, March 16th, 2010

What is it about flexible plastic tubing exactly that makes it such a sought after tubing product?
Actually, the answer is rather simple as to why companies from automotive to medical or even home hobbyists for that matter, select flexible plastic tubing—it’s due to its availability in a wide range of sizes, shapes, and thermoplastics that provide for such diverse uses of flexible tubing.
Not only do these qualities make flexible plastic tubing an attractive choice, but also because flexible plastic tube is easily accessible to the marketplace that makes it a primary choice, particularly in a pinch. And it’s easy to install.

However, one is not only left to the stock availability of flexible plastic tubing at Home Depot or Lowe’s.

For industries requiring very specific design features of flexible plastic tubing for their equipment, they have access to custom plastic manufacturers who can readily assist them with their small diameter flexible plastic tubing needs. Now while the need could be as simple as installing a small diameter flexible plastic tube to finish off a connection in an airline; to those who require a more sophisticated flexible tubing solution such as that which may be replaced in a medical device used in the critical care of a patient during dialysis—the design of a small diameter flexible tubing requires a systematic approach in both design and manufacturing.

It should be reassuring for customers to know that flexible plastic tubing offers as much in terms of reliable performance for a water injection system as it does for a multi-fiber optical cable. But whatever the application, companies should consult with a custom plastic manufacturing company to have the added assurance that are using a highly quality flexible plastic tubing product.


The Trends in Medical Extrusion Tubing Keep Growing

Tuesday, March 16th, 2010

Despite the economy, and the recent surge of job layoffs, there is one fact that remains—people still need quality medical care, and as such there continues to be a growing demand for high-quality medical extrusion tubing amongst those in the medical profession.

As a matter of fact, the average annual growth rate of extrusion tubing worldwide is calculated at 8%, and this is for good cause.

First, rapid advancements in medical device technology necessitate that custom medical extrusion tubing be an essential component for use in both invasive surgical procedures and after-care treatment. The small diameter extruded medical tubes are used in applications from transferring fluids to a patient during a transfusion or intravenous, or the medical extrusion tubing is used for an intubation or during anesthesia, to name a few.

Second, because small diameter extruded medical tubes are manufactured following industry regulations, customers are provided with a pre-sterilized, disposable, medical extrusion tubing product; giving the added assurance that the medical extrusion tube will assist in minimizing the spread of infectious disease during surgery or any other application.

While the reasons for using medical extrusion tubing are vast, there is one driving factor that has affected growth. It’s due to the competency of custom tubing manufacturing companies to meet the demands of the medical industry to make improvements to the extruded medical tubes manufacturing process, such as tighter tolerances or co-extruded new thermoplastic combinations. Employing new precision manufacturing techniques ensures that the medical tubing products are designed and developed to meet the stringent demands of their customers. And due to the growth in demand of medical extrusion tubing, the incentive is built in to respond immediately.


Double Lumen Tubing: Customized to Fit All Patients

Tuesday, March 16th, 2010

The medical professions claims on the proper use of double lumen medical tubing, also referred to as DLT, during cardiothoracic or vascular thoracic surgery would involve a high degree of medical competency in order to reiterate their medical position on the critical use of double lumen tubing.
But one does not require a medical degree to explain or understand that double lumen tubing helps surgeons save lives in the operating room. It’s actually that simple—the reason, not the surgery, as to why double lumen tubing has enabled successful results for this application purposes.

To explain in it’s most basic terms: double lumen tubing consists of two lumens: one bronchial and one tracheal. The double lumen tube provides for ventilation of the lungs during an operation. The intubation process of the double lumen tubing occurs while the patient is anesthetized. The doctor first inserts the tracheal lumen tube into the patient’s trachea before the bronchial lumen tube is connected to allow for ventilation.
Now, here’s the important part.

Before starting the insertion process of the double lumen tubing, doctors need to first determine the diameter of a patient’s bronchus. This is done in order to select the appropriate size double lumen tubing that can easily be inserted and withdrawn into the bronchus without causing the patient harm.

But depending on the manufacturer, the availability of the appropriate size double lumen tube may not be available. However, there is a custom tubing manufacturer who can service the diverse needs of the medical industry. A.P. Extrusion can offer services in the design and manufacturing of small diameter medical lumen tubing to accommodate a wide range of bronchus’ diameters.


Tubing so cool it can take the heat

Tuesday, March 16th, 2010

The mechanical characteristics of thin wall tubing make it an ideal choice for various applications—from its ability to withstand extreme temperature conditions to it providing material strength, excellent insulation and protection from abrasion.

First off, one of the primary benefits of thin wall tubing being able to withstand extreme temperature conditions is in use in sensitive electronic devices where excessive exposure to heat could cause damage and equipment failure.

Why does this happen?

As technology advances, electronic devices, such as integrated circuit boards become more complex. In doing so, the circuit density causes an increase in thermal properties—in other words, it turns up the heat generated inside of equipment.

Thin wall tubing in this particular application helps to cool electronic devices by acting as a conduit to pass airflow to lower the temperature, and as a result keeps the device functioning properly.

Another benefit of thin wall tube concerns its tensile properties. Its relative strength provides necessary assurance to the end user of surgical equipment, for example. During medical procedures, thin wall tubing must deliver superior performance to ensure the safety of a patient. While heat may not be a contributing factor to thin wall tubes failure, it is critical that the tensile strength of the thin wall tube be able can withstand continuous friction and maintain enough gripping strength.

Another common use of thin wall tubing is in packaging protection. In this case, thin wall tubes cut to size may be used as a band around products to aid in tamper detection.
From these varied examples, it’s evident that thin wall tubing offers a wide breadth of performance characteristics to be selected for use in a number of applications.


Rapid prototype models can eliminate psychological stress

Tuesday, March 16th, 2010

From medical devices such as stints to custom-made human implants used in reconstructive surgery, the use of rapid prototype models is rapidly growing in popularity among designers and engineers, due to new and innovative technology—and the reasons are evident.

Looking at anatomical parts as one example:

Rapid prototype models allows for an accurate fabrication of a patient’s implant—whether it’s for bone replacement or prosthesis. Because it’s customized to fit the patient, the benefits of utilizing rapid prototype models allow for the surgeon to conduct preoperative planning and practice in advance of the actual surgery. The surgery thereby becomes less invasive for the patient, reduces reconstruction time, and provides better esthetic results.

Due to this proactive approach facilitated by rapid prototyping, it has also been found to alleviate a patient’s pre-surgery psychological stress, as they have more confidence that the surgical complications will be minimized if not eliminated.

But the benefits of rapid prototyping don’t end there, as it also aids in eliminating risk of product failure. And for engineers and designers who are working to improve product performance, rapid prototyping facilitates faster manufacturing and produces higher quality end products.

After a rapid prototype model is developed, it can be evaluated as to its shape, size and general feel. The level of quality control that rapid prototype models provide allows the design team to answer questions such as: Is this providing the feel we want? Will the prosthesis attach easily? Is there anything obstructive about its design? Will it deliver maximum performance?

Given the design flexibility of rapid prototype models, these questions can be quickly answered and products can be improved more cost-effectively and rapidly.


Got Air? Then you must have a custom medical tube.

Tuesday, March 16th, 2010

Custom Medical Tubing may not be the first thing people think about when it comes to the transfer of air, oxygen air and fluids—but if you work in the medical device industry, it’s likely on the top on your list.

And the reasons are clear—to help keep patients alive and well.
Manufacturing custom medical tubing must be executed following the strictest ISO compliant processes. Custom tubing manufacturers, who develop medical tubes which are generally used in diagnostic and interventional medical products, are required to perform its production in a Class 100,000 clean room. This ensures that the conditions under which the custom medical tube is made is adhering to those standards to result in a disposable end-product that is of the highest quality.

However, regardless of the material from which the custom medical tubing is made, these small diameter custom medical tubes can be extruded into a variety of shapes—circular, square, and oval. And while they can be more costly than other more conventional medical tubes, the expense is justifiable. After all, manufacturing custom medical tubing can be complex and need to be manufactured using the tightest tolerances specified to best suit the application.

In mission-critical procedures, the custom medical tube may be used as a nasal oxygen tube used on a post-operative patient. Medical tubes may also be involved in transferring fluids during transfusions or dialysis.

Research shows that PVC may be the leading polymer used for custom medical tubing, but most custom medical tubing manufacturing facilities can produce the custom medical tubes in a variety of thermoplastics.