Sanitary stainless is a subcategory of stainless steel that has been polished to a near-flawless finish. It’s used in the food, beverage and biopharmaceutical industries for the simple reason that this polish helps to prevent microscopic impurities from settling in the tiny grooves and scratches you’ll find in standard, unpolished industrial stainless products.
3-A.org is the standard-setting organization of record in the food and beverage industries. If you see the 3-A symbol on a fitting, you’ll know it’s approved for sanitary use. All of DuvaSanitary.com’s sanitary product meets that specification.
BPE is an international standard developed as an aid for the design and construction of equipment intended for use in the manufacturing of biopharmaceuticals. All of DuvaSanitary.com’s Biopharm product meets that specification.
Both 3A and BPE are considered to be sanitary, with the ID being polished to an RA of 32 or better. However, while 3A tubing and fittings are polished to 32Ra and often better, BPE comes in several finer finishes, the most common being SF1 (PL) and SF4 (PM). These finishes make them better suited for pharmaceutical use where even the slightest impurity cannot be tolerated in the line.
- SF1 – 20Ra Max ID Electropolish / 32Ra Max OD
- SF4 – 15Ra Max ID Electropolish / 32Ra Max OD
Additionally, BPE fittings have extended tangents, which accommodate orbital weld heads. If you want to orbital weld an elbow but only require the 3A polish specification, you can purchase Automatic Weld Elbows, which have extended tangents, at 32Ra Max ID.
BPE fittings and are available in Butt Weld and Tri-Clamp only.
Almost every style of fitting offered by DuvaSanitary.com is available in 304 and 316. Why choose one over the other?
304 is the most common stainless steel alloy, used for its appearance, durability and resistance to corrosion. However, its corrosion resistance in acidic and saline environments is inferior to 316. It is the less expensive of the two alloys, and may be the best choice under ideal environmental conditions.
316 stainless has the same chemical composition as 304, but with the introduction of Molybdenum for greater strength and hardness, giving it superior resistance to corrosion from chlorides. This usually translates to longer life in the process line.
You may hear the term “Tri-Clover” used in the process industry, and wonder if this is different to Tri-Clamp in some fundamental way. The answer is that they are one and the same, identical in every way. Tri-Clover was an Alfa-Laval trademark for their sanitary clamp fitting type. The term became commonly used in the industry, but while the name Tri-Clover was copyrighted, the design was not. Soon other manufacturers entered the marketplace, and the name Tri-Clamp was born. If you’re being asked to locate a certain Tri-Clover fitting or valve, you can safely purchase Tri-Clamp.
Tri-Clamp fittings are used to easily mate two or more elements in a process line. This is accomplished by connecting the flanged ends of fittings, with a gasket in between, and securing the connection with a clamp. It’s very important to make sure the gasket is properly seated before tightening the clamp, as improper alignment is a leading cause of leaks and contamination. The clamp should be tight and secure, but not overtight. If the gasket bulges, it may push into the pipeline. This can create spaces for bacteria to develop.
There are several commonly used gasket materials. Below are the types offered by DuvaSanitary.com.
- Buna – Rubber gaskets for general purpose industrial sealing at moderate temperatures (between -22° and 250°F).
- Viton – Rubber gaskets providing indefinite seal from 5° to 400°F, and an excellent seal at 600°F up to 48 hours.
- EPDM – A very stable rubber-like gasket that resists heat, oxidation and aging, with flexibility at low temperatures. Working range is -60° to 300°F.
- Teflon – Also known as PTFE, these chemically resistant plastic gaskets are unaffected by most corrosive liquids and gasses from -400° to 500°F.
The clamp you choose will depend on the pressure and temperature of your process line. Heavy Duty and High-Pressure clamps are available at DuvaSanitary.com. To help you decide which is best for your application, you can consult the Service Pressure Rating charts on our clamps pages.
All tubing, valve and fitting sizes are determined by the Outside Diameter (OD) of the tube. In order to properly determine the size you require, do one of the following.
- Measure the OD of the tube end of your existing tube or fitting. If possible, you can place the tube end on a piece of paper and trace around the edge, then measure from one side to the other. Or, simply place a ruler over the tube end itself, and measure from one outer edge to the other.
- Measure the OD of the flange end. You can do this using the same process as above.
Cleaning and maintaining your Tri-Clamp fittings is easy. They can be cleaned in place, but they’re also easily broken down and replaced after maintenance.
If you’re a brewer, distiller or wine maker, or if you’re simply running water through your lines, you may be able to complete several runs of production before inspection or cleaning. Or, like makers of food and pharmaceutical products, you may want to inspect and clean after every use.
The flanged ends of your fittings are a very important area of focus when cleaning. Avoid scraping as a cleaning method, and this will damage the polish and deem the fitting unfit for sanitary use. Also, make sure to check your gaskets for buildup, cracks, tears, stains and debris. Gaskets can be regularly replaced for very little cost, much lower than the cost of a ruined batch.
Regularly clean your valves as well. DuvaSanitary.com’s valves have available repair kits, if cleaning does not achieve the desired result.
Tri-Clamp is by far the most commonly used fitting type in today’s food and beverage industries, making up over 65% of fittings sold in the United States. However, there are alternatives that may be right for you. DuvaSanitary.com offers the following alternative styles.
- Butt Weld – These fittings are permanently welded in place, and require a qualified welder for proper installation.
- I-Line – This fitting type is similar to Tri-Clamp, but uses a different flange face design. Interlocking design creates a safe compression connection that is resistant to vibration, temperature and pressure.
- Bevel Seat – This fitting style uses a nut and gasket to complete a connection.
Knowing as many parameters as possible will ensure that you have selected the correct hose for your intended application. To remember those parameters, we have a helpful acronym, S.T.A.M.P.E.D.
- Size – Refers to the overall dimensions of the hose required for your particular needs. You’ll need to know the hose ID, OD, and length. If the assembled length is critical to the hose’s application, you may need to determine overall assembled lengths (length including fittings).
- Temperature – Refers to the temperature of the application, which is an important factor, particularly how hot it is. Consider both internal (media and friction) and external (ozone and sunlight) temperatures. Most rubber compounds will naturally begin to break down as it approaches 200° Fahrenheit. There are specially blended rubber compounds that are made to withstand higher temperatures, such as EPDM and Viton.
- Application - Refers to the environment in which the hose is being used. Is there a direct exposure to sunlight? If so, your customer will need a hose that is made from a compound that has ozone resistance, such as EPDM. Is there direct exposure to oil or petroleum products? If so, your customer will need a hose that is made from a compound that has oil or aromatic resistance, such as NITRILE.
- Media - Refers to what product is running through the system. This parameter is important because the media will come in contact with the ID of the hose. Certain rubber compounds are made to withstand particular media. For example, NITRILE is good for oil/petroleum-based products, and GUM is good for abrasives.
- Pressure - Refers to how much pressure is going through the system. Be aware of any spikes in pressure and allow for these drastic changes in the design and selection of your hose. It is equally important to be aware of the correlation between temperature and pressure. A hose cannot be used at its maximum rated working pressure and maximum rated temperature at the same time. For more information, check out our Pressure and Temperature Recommendations under Resources.
- Ends - Refer to which fittings are needed and how they are to be attached to the hose. A hose assembly is rated for the lesser of the working pressure of the hose and the fittings. So, a 4-inch 200psi hose with aluminum cam and groove fittings double banded on will only be rated for 100psi.
- Delivery - Refers to when the assembly is expected on a job.