Tag Archives: Hose Master

Metal Hose Application Do’s and Don’ts – Part 2

Metal hose applications can get tricky. Sometimes you can have problems or failures due to the surrounding piping system or because of the way the hose is installed.

Today we are going to discuss Part 2 of the do’s and don’ts when it comes to installing metal hose assemblies in a metal piping system.

Hoses can take a great deal of damage when they are torqued. Twisting it stretches the corrugations and the fitting wells and can cause it to fail. To prevent torque, don’t install the hose off-center.

When it tries to flex, the assembly will be torqued. Do install the hose in-line with itself; called in-plain. This prevents it from torquing when it flexes, and you should stick to one plain of movement. A quick test for in-plain could be done with either a sheet of paper or a flat surface like a table.

When handling long lengths or coils of hose, it’s important to make diagram of a hose wrapsure the hose doesn’t get twisted. Don’t grab one end of the coiled hose and walk away or pull on one end with the other end fixed. This will torque the hose. Do coil and uncoil it properly. Roll it like a tire or pretend like it would be on a reel and try not to twist it.

When installing a hose, significant physical damage can be done to the fitting, the welds, and the braid with the various tools that may be used to install it. Don’t use a wrench or other tools on the hose anywhere but on a hexpad. Gripping the hose by the braid, the braid collar, or the threads will damage the assembly. Do use a second wrench or a swivel-capable fitting when applicable to prevent twisting during the assembly installation.

Torquing the hose during installation is common and can be an issue. If the existing piping does not have any kind of swivel or rotation, don’t use an assembly with fixed-ends fittings at both ends. Otherwise, installation could torque the assembly and strain into service.

Do use a swivel, floating flange, or union, or other fitting that allows the hose assembly to twist during installation.

Follow these tips can help maximize your hose safety and the safety of your plant personnel. If you missed it, make sure to check out Part 1 of the video series.


This video was produced by Hose Master and can be found on their Youtube channel or on their website.

PTFE Liner for Corrugated Metal Hose

Gallagher Fluid Seals is a distributor of Hose Master corrugated metal hose and expansion joints.  With the largest in-house fabrication footprint in the U.S. of any metal hose manufacturer (350,000 square feet of manufacturing space) and 80+ ASME IX Certified welders on staff,  Hose Master delivers the highest quality products for the most demanding applications.

The following article can be found on Hose Master’s Insights Blog.


Should I Install a PTFE Liner Inside a Corrugated Metal Hose?

by Frank Caprio, Dean of Hose Master University
Corrugated Metal Hose
See the hose peeking out between the collars? Me neither.

We get various requests from our customers for non-traditional hose assembly constructions that they believe will help them solve tough application problems. Over the years, we’ve seen a lot of these, and some are pretty inventive, even if they’re not the best solution. Some other proposed solutions…not so good!

One especially challenging application that can drive people to consider specialized solutions is when the hose is exposed to corrosive media or environments. Typically, corrosion can be avoided simply by selecting an alloy that is resistant to chemical attack. However, certain refinery applications (such as those found in Cokers or FCCUs) entail operating conditions where some manufacturers recommend a special corrugated metal hose assembly which has been fitted with a liner made from smooth PTFE tubing. While this special construction sounds good in theory, it can create more problems than it solves. Let’s take a closer look at PTFE-lined corrugated hoses.

Continue reading PTFE Liner for Corrugated Metal Hose

Basic Types of Metal Expansion Joints

Much like elastomeric expansion joints, metal expansion joints are used to preserve the integrity of a piping system where the piping is subject to changes in temperature, pressure, vibration, compression, extension, cyclical movements or movements required by usage.

Metal Expansion Joints - FabricationOftentimes, metal expansion joints are used when an elastomeric joint simply cannot handle the extreme conditions – generally high temperature, large temperature range, or high pressure exists in your application. Generally, metal expansion joints can be used from -450°F to +2000°F, depending on the metallurgy, and can also handle pressures from full vacuum to 3,000psi.

Continue reading Basic Types of Metal Expansion Joints

Assembly Components and Value: Corrugated Metal Hose

If no special options or accessories are needed, there are four basic components to a corrugated metal hose: The tube (or hose itself), the braid, the braid collars, and the fittings. There may be times where an unbraided hose will work, but most applications require an assembly containing these four components. Let’s look at each of these components and their function as part of the total assembly, and how they all work together to provide value.

Metal Hose Components

Fittings
Corrugated metal hose assemblies are able to incorporate virtually any fitting that is able to be welded to the hose ends. Because of this, it is critical that the end fittings selected are appropriate for the intended application. Make sure the fittings are the right size, alloy, and pressure (designated by pipe schedule, tube gauge, pressure class, etc.) for the application, including any piping standards or specifications that must be met.

Braid Collars
Braid collars are used to join the inner corrugated hose and the braid together during the cap welding process, where a TIG weld joins the hose, braid, and braid collar into the cap weld bead. A good cap   weld becomes the base for the subsequent attachment weld. Additionally, the braid collar serves to isolate the last few corrugations from movement, as their cycle life may be compromised by the heat required to properly weld fittings to the hose. It is critical that the braid collars are sized properly in order to facilitate welding and to protect the last few corrugations from movement.

Continue reading Assembly Components and Value: Corrugated Metal Hose