Reviewing Flexible Hose End Connection Types & Use Cases
Reviewing Flexible Hose End Connection Types & Use Cases
July 1, 2019 | Doug Nordstrom
End connections serve a single purpose: to safely and securely connect components within a fluid system. But there are a variety of flexible hose end connection types to consider when designing your fluid system, and selecting the wrong type could undermine your process, put workers at risk and compromise your bottom line. It’s important for design engineers and facility managers to routinely review the performance of their end connections and consider if a different type could improve efficiencies and sample quality.
After selecting the core tube material, reinforcement layer and cover for your hose, it’s time to select end connections. Consider the following three items: industry standards, hose type and system specifications.
1. Consider Your Industry’s Standards
Different industries require end connections designed for specific uses. Selecting end connections designed specifically for your industry’s use case is key to achieving and maintaining high performance in your fluid system. Below are some common industry uses for end connections, and the different specifications required for end connections used for those applications.
- Pharmaceutical, biopharmaceutical and biotechnology
In the pharmaceutical and biotechnology field, sanitation and hygiene are often of utmost importance when it comes to fluid system design. End connections used within this industry are designed with that in mind – they are more easily cleaned, either by taking the system apart for a thorough cleaning or using a CIP (clean-in-place) process. Surfaces are designed to mitigate bacteria growth, and they are corrosion resistant.
In the semiconductor manufacturing industry, material purity is typically the top priority for fluid system design. End connections used within the semiconductor market are high-purity for use in sensitive environments, with very fine threads, designed and coated with material to enhance resistance to build-up and contaminants.
- General industrial
For many other industrial fluid system applications, design engineers are most concerned with the ability for end connections and fittings to perform under high pressure. These end connections are rated based on psi (up to 60,000 psi in top-rated high-pressure fittings) and sometimes require additional tube preparation to handle the pressure requirements.
2. Consider Your Hose Requirements
- Permeation and chemical compatibility
End connection requirements may vary based on the corrosion requirements and permeation needs of the application. Hoses of any material are permeable to a degree, and each should be tested for application compatibility before use. Likewise, chemical compatibility (i.e., a lack of chemical reaction when two substances come into contact) is necessary for many fluid system applications. Finding the right hose materials to mitigate chemical reactions, system damage or corrosion is critical.
- Pressure and temperature ratings
Depending on the application, fluid system components must be able to withstand specific pressures and temperatures. In high-pressure and high-temperature applications, like hydraulic systems and other general industrial applications, single- or double-braided annular hoses with a corrugated bore are a common selection. High-pressure and high-temperature requirements often go hand-in-hand with dynamic applications in which a hose will need to flex, or change position, which can also impact hose selection.
- Hose material
Metal cores are a good choice for general needs. Metal core hoses are rated for temperatures between -325° and 850° F, which sometimes makes them the only material choice for extreme temperatures. Silicone, on the other hand, is a common choice for sanitary applications because of the material’s flexibility. However, silicone has limited chemical compatibility and is absorptive, which can lead to contamination. Because of silicone’s drawbacks, it’s being replaced by fluoropolymer cores in sanitary applications. PTFE, PFA and FEP are three common fluoropolymers, with slightly higher temperature ratings than silicone. Additionally, thermoplastic (nylon) hoses are commonly used in hydraulic applications because they can withstand high pressures, and rubber hoses are an economical, general purpose choice used mostly in low-pressure applications.
3. Consider Your System Specifications
Now consider the material and type of end connection in your system to which the hose is being connected. The material of the system and hose end connections should be the same. Many types of end connections are similar in appearance, but they may have minor dimensional or thread differences—meaning they are not truly interchangeable.
Some other miscellaneous items to consider when selecting the proper hose end connection types:
- Think about the ease of installation and/or permanence. How often will these end connections need to be replaced? How difficult will it be to replace them regularly, if needed?
- Think about inventory simplification. While fluid system performance, compatibility and specifications are primary concerns when selecting hose end connections, it’s smart to also consider the operational impact of your selections. Consider exploring how to more easily store components and how to streamline the reordering process, or how to consolidate vendors and component OEMs.
- Consider the cost of your hose end connections. Cost is always a consideration when selecting components for your fluid system, but remember to consider the lifetime cost of frequent replacements that could undermine the up-front savings of cheaper components.
The considerations for flexible hose end connection types above are not foolproof, however. It is up to the individual design engineer to evaluate the total fluid system design when selecting end connections and other components.
Swagelok Product Selection Tools
Swagelok has a number of product selection tools available for use online, including:
- Cv-Calculator – for help calculating Cv and flow for regulators and other components
- CAD-Templates – more than 1 million Swagelok CAD templates and sales drawings in 2D and 3D file formats
- Regulator Flow Curve Generator – a tool to provide your unique flow curve based on a set of user-specified application parameters for RHPS series regulators
- MPC Configurator – software for configuring custom modular platform component systems
- Material Selection Guide – for help simplifying the selection of materials
For additional help with product selection to design your fluid system, contact your local Swagelok sales and service center.