Category Archives: Metal Hose

Measuring Metal Hose Assembly Lengths

“Which way do I measure this metal hose?”

A common question among some customers who use metal hoses is: “Which way do I measure this metal hose?” Well, there’s a few different options.

  1. The first method is to measure the overall length of the assembly.
  2. Or, the live flexible length of the hose assembly can be measured.

Live Length vs Overall Length

Traditionally, the live length – or the amount picture showing live length versus overall lengthof flexible hose between the fitting – is used to determine whether there is sufficient hose length to accommodate a certain offset or movement, whereas the overall length of the assembly would be used to determine if the hose is going to fit in an application.

When measuring the overall length of the hose assembly, make sure to measure the overall length via end-of-fitting to end-of-fitting and if it has floating flanges on it, remember to measure to the face of the stub end on that floating flange.

JIC Swivel Fitting

If it’s a female JIC swivel fitting, however, it’s not necessary to measure the overall length to the end of the nut. Measure to the seat of the JIC inside the female swivel fitting. This is the standard for the metal hose industry.

Some customers may measure the overall diagram showing measurements with centerlinelength to the end of the JIC nut because some standards are measured differently by hydraulic manufacturers. If there are elbow fittings on the ends of the hose, metal hose industry standards dictate that measurements should be taken to the centerline of those elbow fittings rather than measuring the outside of the radius of the bend on those elbow fittings.

Laid flat with no kinks or bends

When measuring the length of a hose assembly, make sure it’s laid flat without any kinks or bends in the assembly. If it’s a strip wound hose assembly, ensure that strip wound hose is in its relaxed length, midway point between fully compressed and fully extended. Then, take the measurements on the length of that assembly.

For a great visual representation of measuring metal hose assembly lengths, watch this informative video below from Hose Master:


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

For more information, contact Gallagher Fluid Seals or call 1-800-822-4063.

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

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