For our next spurt of blog posts, we’re going to focus on one of mankind’s greatest inventions-welding (welding actually ranked #10 on Scientific American’s list of greatest inventions back in 2013). With April being National Welding month, we’re going to take a few posts this months to talk about the history of welding and then focus more specifically on sanitary welding and welding in the high purity process industry.
The history of welding goes back to the Bronze Age. Man’s first attempts at joining metal were done mostly through a process known as forge welding. It works by heating the metal pieces until they glow red and soften. When they’re soft enough, the welder mashed the two parts together with a hammer and allowed them to cool. This type of metal working was popular up until the Industrial Revolution when new forms of welding were devised to meet industries evolving needs.
While the history of welding is interesting, we’ll spend the rest of this post focusing on the common welding techniques of today and where we see them used.
The easiest place to start is the welding process we’re most familiar with- arc welding. Arc welding is a type of welding that uses a power supply to create an electric arc between an electrode and a base material to melt the metals together at the welding point. There are two main methods of arc welding- consumable and non-consumable electrode methods. An example of consumable welding is gas metal arc welding (GMAW), also known as MIG (metal/inert-gas). This is a semi-automatic or automatic process in which a continuously consumed wired is fed and acts as both the electrode and filler metal. At Holland we use MIG welders to join structural material, like stainless steel skid frames.
The most common type of welding we see in the high purity industry is another form of arc welding that uses a non-consumable electrode and separate filler material to join two parts. Known as gas tungsten arc welding (GTAW) or tungsten/inert-gas (TIG) welding, TIG welding is a manual process that uses an electrode made of tungsten, an inert gas mixture. TIG welding may or may not use separate filler material to affix joints. This process is especially useful for welding thin materials, but because it is a manual process (with the exception of orbital welding, which we’ll touch on later), it requires a significant amount of skill and can only be accomplished at relatively slow speeds, relative to MIG or other welding processes.
As we just mentioned, another method of TIG welding common throughout the biopharmaceutical industry is orbital welding. Orbital welding is an automatic process whereby an arc is rotated mechanically 360 degrees around an unmoving work piece. This technique does not use a filler material. By taking the human out of it, we see consistent, high quality welds that require little operator intervention. Orbital weld beads end up being so smooth and consistent that BPE guidelines don’t even make us polish ID welds. Most of the high purity welds we create for bio pharmaceutical skids and modules are automatic orbital TIG welds
Now that we’ve talked about arc welding, we’ll spend the rest of the post focusing on some processes that are less common in the high purity industry, but pretty cool nonetheless.
The first process we’ll touch on is friction welding. Friction welding uses pressure and movement to generate the heat we need to cause welding to occur. Friction welding is commonly used to join dissimilar materials. This is helpful in aerospace applications where we might want to join a lightweight aluminum part with a high strength steel. Because of the large difference in melting points between aluminum and stainless, arc welding procedures would be useless and a mechanical connection would be required. But friction welding provides a full strength bond with no additional weight.
Next, let’s look as laser welding. We do see laser welding from time to time in the sanitary industry. Laser welding is a process that uses a high power laser beam to provide a concentrated heat source, allowing for narrow, deep welds and high welding rates. Because of its speed, laser welding is commonly used in high volume applications. Laser welding provides high quality welds and the focused beam results in small heat-affected zones, resulting in little distortion of the part.
Finally, we’ll talk about ultrasonic welding. Ultrasonic welding is cool because it is commonly used to join plastics and dissimilar materials. Ultrasonic welding uses high frequency ultrasonic vibrations applied to work pieces held together under pressure to create a weld. We think ultrasonic welding is interesting for its potential uses in affixing single use needle hubs to cannula.
This is by no means a comprehensive list of welding techniques, but a brief overview on a few processes that we see in our industry or just think are cool. We’ll spend the next couple of posts discussing sanitary hand and orbital welds a little more closely. If you have any questions about your sanitary welding application, contact a Holland Sales Engineer today
In today’s blog, we’re going to revisit a product we’ve focused on in the past- the Quattroflow quaternary diaphragm pump. The Quattroflow series of pumps is one of our newer products offerings that continues to innovate, offering our biopharmaceutical customers scalability, flexibility, and performance that traditional product offerings can’t match. As Quattroflow gains larger market acceptance, they have continued to push the envelope to meet customer demands and bring new products to market. Today we’ll take a look at their latest product offering- a compact version of their popular QF 1200.
For some time now, the Quattroflow pump has been available in the 150, 1200, 4400, 5050, and 20K sizes, with all but the 20K being offered with both stainless and single use heads. The smallest of these sizes, the 150 is offered with an integrated drive and controller standard. This small footprint and wide turndown makes the 150 perfect for lab and low flow applications.
When we scale up to the QF1200, however, the Quattroflow 1200 has traditionally been offered with separate pump and control boxes. The 3 phase, 0.5 HP motor meant that we needed to use a variable frequency drive to achieve the wide ranging turndown the Quattroflow is known for. While this is an effective solution, it meant we would need two enclosures- one for the pump and one for the VFD. This relatively large footprint presented challenges when mounting the QF1200 to a skid or when trying to make room for it on an already crowded lab bench.
To solve this problem, we are now excited to offer the Quattroflow 1200CV. Similar to the QF150, the QF1200CV combines controller, motor, and pump into an all-in-one unit that is perfect for customers with a tight space requirement. The compact version of the QF1200 uses a brushless DC motor that is similar to one used in the QF150 and affords use the same range, turndown, and low pulsation the Quattroflow pump is known for.
Currently offered with a single phase, 220V motor, the QF1200CV is available with an optional 0-5V DC input for speed control (which can be easily scaled to a 4-20 milliamp input). The QF1200CV is available with standard ¾” TC stainless and single use heads. Single use heads are available in both a machined polypropylene as well as an injection molded polyethylene. The polypropylene chamber is ideal for high temperature and SIP applications, while the molded head is economical and ideal for applications where the chamber will be gamma irradiated and disposed of following a campaign. All soft parts for both the single and multiuse heads are fully characterized, made of USP Class VI materials with extractable and leachable reports available.
To conclude, the QF1200CV adds another option and flexibility to one of the most scalable positive displacement pump technologies on the market. If you have questions about your next biopharmaceutical application or to see if the Quattroflow line of pumps is right for you, contact a Holland Sales Engineer today.
We’ve talked plenty about sanitary pumps in this blog in the past. One topic we’ve touched on, but haven’t explicitly detailed, is NPSHA. Today’s post will focus on what NPSHA is and how it applies to your sanitary pumping application.
To begin, NPSHA stands for Net Positive Suction Head Available. NPSHA should not be confused for NPSHR, which stands for Net Positive Suction Head Required. NPSHA is a measure that corresponds to the level of pressure at the sanitary pump suction. The high the pressure the gauge at the pump suction reads, the higher the NPSHA, and the better the pump will operate. This pressure can be easily measured with a gauge at the pump inlet. Remember, most pressure gauges scales to atmospheric pressure, meaning they read zero when there is no pressure other than atmosphere (14.7 psi). In most cases, we can assume gravity will give us 34 ft of head.
The most important part of NPSHA is the head component. We’ve talked about fluid head in the past, and for NPSHA, the component of total head we’re most interested in is static head. The static head is the distance between the fluid level and the inlet of the pump. Generally speaking, the greater the static head, the greater the NPSHA.
After we know what atmosphere is giving us and how much static head we have, we need to net out or system losses. This is mainly friction loss. We’ll lose head as the fluid flows or is restricted through the system. The most common friction loss adders include, elbows, valves, and strainers.
So once you know what your NPSHA is, how do you know if you have enough? Well, that is where NPSHR comes back in. The pump manufacturer tests the pump under various suction head conditions and provides a requirement or NPSHR for each flow condition on the pump curve. All we have to do is check our NPSHA against our NPSHR and we’ll know if we have enough. Most pumps can operate with a suction pressure that is below atmospheric (below 34 ft or 14.7 PSIA). In these situations, however, it is very important to keep the suction line primed through the use of foot or check valves.
So what happens if in your pump application you don’t have enough suction head? What do you do? Well first, it will be pretty apparent, especially with centrifugal pumps, because you won’t be getting the flow you expect out of it. You may also have pump cavitation. It will sound like marbles are going through you pump.
So how do we fix it? Well, one factor that is commonly overlooked is supply tank level control. You may start out with a full vessel and have plenty of NPSHA, but as fluid is moved the level in the tank decreases, our NPSHA will also fall. To solve this, we can control the tank level with either point or continuous level sensors, or we can raise the height of the tank so that we’ll have enough suction head even at low tank levels. Another solution would be to lower the level of the tank inlet relative to the tank fluid level. You could also pressurize the vessel to juice your NPSHA.
Another issue we see often is locating elbows or fittings too close to the inlet of the pump. Fittings, such as 45’s, 90’s, and valves will all detract from the NPSHA. We recommend minimizing the number of fittings leading up to the pump. We also want to locate the pump as close as possible to the tank, avoiding long straight lengths leading up to the pump. We also want our suction line to be as large as possible. This is why the inlet of a sanitary pump is usually larger than the discharge.
So there you have it- a detailed overview of most everything you’d want to know about NPSHA in your sanitary application and how you can fix the problem. Remember, if you’re experiencing noisy operation, capacity loss, or pitting, check to make sure you’re supplying adequate pressure to the inlet pump. If you have any additional questions about your next sanitary pump application, contact a Holland Sales Engineer today.
Some of the most interesting requests we get every day at Holland are about the piece of equipment we sell that tends to have the longest life span- an APV High Pressure Homogenizer. The APV Gaulin and Rannie type machines are the well-built work horses of many food, pharmaceutical, and personal care products where a stable emulsion or mixture needs to be created. Because they are so critical to the process (as well as the large upfront cost), it is not uncommon for homogenizers to be in service for 20, 30, sometimes even 40 years. There is also a sizeable aftermarket for high pressure homogenizers, so we frequently have customers who are not the original owners of their machine. Fortunately, the good folks at APV and SPX have made it easy for us to identify a machine and spare parts based on its unique serial number. This post will discuss the APV homogenizer serial number system and where to look on your machine to figure out which machine you have.
To begin, let’s talk about where you look on your machine to find the serial number. Generally speaking, on cast iron or painted frame machines (those old blue beasts), the serial number will be found stamped on the top frame edge, on the right hand side facing the cylinder block. The machine identification tag is located on the rear wall of the plunger well. Machines with a stainless steel or mild steel skin (newer machines), will have the serial number stamped on the left side of the base casting, just above the motor compartment. Many newer machines will also have a tag calling out the serial number.
So now that we know where to find the serial number, let’s talk about what those numbers mean. Since 1939, APV has been using a four digit serial number on all production scale Gaulin homogenizers. There are about 68 machines that are an exception to that rule from 1959 and all machines made at 1986 have had 5 digit serial numbers. That means the last 3, 4, or 5 digits are the unit serial number. The numbers preceding the serial number indicate the date of manufacture. For example, let’s say you pull the number 10757-927 off of your machine. That would mean that this machine was built on January 7th, 1957 and the serial number is 927. The month, day, and year were used until 1960, after that, only the month and year were used (for instance, 157-927).
So hopefully this helps you better identify your APV homogenizer or at least gives you an idea where to look. When order spare parts or making changes to your machine, the model and serial number are the two most important pieces of information you can provide a customer service person at Holland. If you have any additional questions or needs for your sanitary high pressure homogenizer, contact a Holland Sales Engineer today.
We’re going to talk a little bit about a service Holland has been offering for some time- Magnetic or “Mag” trap verification and validation. In today’s blog, we’ll give you an overview of how sanitary mag trap testing is performed, why you should have it done, and our current service offerings.
To begin, sanitary magnetic or “mag” traps have been used in the food processing industry for quite some time to prevent two things- adulteration of product and process equipment protection. Keeping metallic objects out of your product not only protects consumers, but also brand name risk and costly recalls. Mag traps will also protect pumps, valves, and instruments from damage. This helps avoid downtime and other costly repairs. Because most customers are familiar with a Mag Traps and what they do, the rest of this post will focus on how we test them.
Historically, there have been two ways to measure magnet strength- the pull test and through the use of an electronic device known as a Gauss meter. The pull test method is used to determine the relative strength of a magnet by approximating the holding force through the use of a scale and spacers. This method is not quantitative, presents a pinch hazard for operators, and is generally not accepted by 3rd party auditors.
While the pull test method has been used since the 1960s, recent improvement in microelectronics have brought economical, portable gauss meters to market. A gauss meter is an electronic instrument that measure the number of lines of magnetic flux emanating from a magnet. A gauss, as alluded to previously, is the number of magnetic flux lines per square centimeter. Gauss meters are definitive, accurate, and repeatable. They can also be calibrated by instruments traceable to NIST and in accordance with accepted ISO standards. Gauss meters are also capable of taking measurements of over 10,000 gauss, which is common with the rare earth magnets used in modern Mag Traps.
Due to increasing food safety concerns and requirements by 3rd party auditors, third party mag trap verification has become an increasing request from out customers. In response to this need, Holland has incorporated gauss meter testing and mag trap verification into our already robust quality and calibration programs. Holland offers digital gauss readings and verification both on at our facility or at our customer’s facility using our in-house DC gauss meter.
Verification starts with visual inspection of trap elements for and signs of pitting, cracking, or other wear to ensure the magnets are intact, followed by measurement of all magnetic probes with a DC gauss meter. Due to our close relationship with several mag trap OEMs, including Cesco, we’re able to reference our readings to the measurements taken when the unit shipped to ensure the magnets are still performing like new. Following testing, we provide a certificate of verification and include meter calibration certs in the turn over package as well.
As mentioned above, we are proud to offer this service both at our facility or our customer’s and we’ve traveled as far as Trinidad and Tobago to do on site testing. If you have any additional questions about our Magnetic Trap verification service offerings, please contact a Holland Sales Engineer today.
Today we’re going to revisit a topic we’ve discussed previously on this blog- spring check valves. A check valve is a device that is used to prevent reverse flow in a pipeline. Check valves come in a variety of types, with the two most common in the sanitary process industry being the ball and spring check types. Today we’re going to specifically focus on selecting sanitary spring check valves and some unique features you may want to keep in mind for your next application.
One of the most common sanitary check valves we use on a day in and day out basis is Waukesha Cherry Burrell’s W45 spring check valve. We like to use this valve not only because it is available with a variety of springs, elastomers, and surface finishes, and also because it offers two different seal designs for the spring loaded seat- a standard O-ring seal and a Tri-ring seal option. So which seal type should you use for your application? Let us explain.
The O-ring seal design is ideal for general purpose applications that require cracking pressure and pressure drop across the valve to be as low as possible. This is a general duty seal designed for a wide range of products and laminar flows.
So what are you to do in more violent applications, you might ask. What kind of seal should you look for if you have high flow velocities, such as those found in CIP applications, or if you are trying to prevent backflow of thick, viscous, or sticky products that tend to crystalize on sealing surface? Well, we have an answer for that- the Tri-ring seal design. If you order your Waukesha W45 check valve with a Tri-Ring stem, it is supplied with a heavier spring. The heavier spring is ideal for applications where the fluid velocity exceeds 5 ft./second. The geometry of the Tri-Ring stem also makes it ideal for liquid sugar applications where sticky products can have a negative impact on valve performance.
So which one should you use? Well, it depends largely on your process application. Fortunately, if you pick the wrong seal type initially, or even if you have an existing W45 check valve with O ring seal, Tri-Ring replacement stems are available from Holland Applied Technologies and supplied as ready to install cartridges.
So there you have it- one more tool you can use to fine tune your high purity process to achieve optimal performance. As we’ve focused on throughout this blog, selecting the right product- as well as the right product features-for your application is essential for success in the challenging sanitary fluid handling industry. While the correct products sometimes come with a higher upfront cost, by using high quality products specifically designed for your application, you can maximize both service life and performance, as well as minimize total cost of ownership- saving far more than the high initial investment in the long run. For more help with your next sanitary check valve or high purity processing need, contact a Holland Sales Engineer today.
At Holland Applied Technologies, we are actively involved in most corners of the sanitary and high purity fluid handling industry. We have a great deal of expertise and application knowledge ranging from pet food to bioreactors. One niche we have been working with more and more is the craft brew industry. This really shouldn’t come as much of a surprise- in 2013 the craft brew industry accounted for $14.3 billion of the $100 billion beer market and has continued to grow through 2014 and into 2015. As we continue to deal with craft and microbreweries, we found the same questions coming up. This post will be the first in a series of posts focusing on applications and common questions we have helped our craft beer customers with.
About 18 months ago, we were contacted by a local OEM provider of counter pressure beer canning systems. Dealing almost exclusively with craft breweries who pride themselves on making (and canning) the perfect beer, this OEM was having a foam issue. The problem was occurring as beer from transferred from the brew kettles into the fill bowl atop the machine. Traditionally, machine manufacturers have used centrifugal pumps for this transfer operation. The C series pump has long been the work horse of the beer industry. But what this machine manufacturer was finding was that the centrifugal pump-which by definition uses rotational kinetic energy move fluid- was causing excessive foaming within the fill bowl. This resulted in partial can fills and the loss of a significant amount of product at the start of every canning run.
To help solve this problem, Holland suggested the use of a Graco Saniforce air operated double diaphragm pump. Instead of imparting so much rotational energy that can result in foam, the AODD uses compressed air which alternates between chambers to create a partial vacuum and cause the diaphragm in the opposing chamber to create suction. Coupled with a series of ball check valves, this results in the fluid being pushed and pulled through the pump chambers- a much less torturous path for the beer. Other benefits to Graco’s Saniforce pumps include great suction lift, stainless steel construction, 3A compliant surface finishes, the ability to handle a range of viscosities, high efficiency, and good self-priming capabilities.
After extensive testing, the OEM found that the Graco Saniforce largely mitigated the foaming issue. In doing so, the counter pressure canning systems were more efficient, resulting is less waste and higher throughput. And because the only utility required to operate them is compressed air, we no longer needed to worry about what kind of electric power the end user had on site.
So for your next beer transfer or filling application, remember- you have choices outside of the trusty old C114. The AODD Graco Saniforce pump is great for applications that require suction lift, low shear, and high differential pressure applications. That’s not to say that centrifugal don’t have a place in a brewery- they most certainly do. In fact, we’ll elaborate further on their application, as well as other pump technologies used in craft beer applications in future posts. But if you can’t wait for the future posts and you have a question now, please contact a Holland Sales Engineer today for more help with your next beer pumping application.