Digital montage (1)

The Fluid Systems Engineering and Management Blog

by Swagelok Northern California

Save Time With Our Multihead Hydraulic Swaging Unit

by Jeff Hopkins, on 4/10/19 8:55 AM

We have a training video and printed instructions to show you how it's done

"CAUTION: Use of tubing below the recommended minimum wall thickness may result in the tube sticking in the die head."

- Swagelok Multihead Hydraulic Swaging Unit (MHSU) - Setup and Operating Instructions

Have you ever had to stop a car without the boost of power brakes? That shows the difference that hydraulics make. The same principle explains how the Swagelok multihead hydraulic swaging unit gives you a boost when you want to preswage Swagelok ferrules onto tubing prior to assembly. With the power of hydraulics you'll save time on  assembly and installation, and you'll get consistent performance.

You'll only get great results if you use the tool properly. That's why we offer two forms of instruction on the multihead hydraulic swaging unit. We have a video (below) to show you how it's done, and detailed instruction in PDF that you can refer to at any step of the operation.

All-in-one kit


We pack everything you need in a kit. We have one kit for tubing diameters of 1/2 inch to 1 inch (12mm to 25 mm), and a separate kit for tubing diameters of 1 inch to 2 inches (25 mm to 50 mm).
The heart of the kit is the hydraulic cylinder and hand pump, connected by a hose to a special housing where the swaging takes place. The kit also has three different die heads, a set of chamfer blocks, a set of gap inspection gauges and a pair of pliers for removing and inserting the retaining ring in the hydraulic housing.

You don't even have to supply your own safety glasses. There's a pair in the kit.
Everything fits inside a strong plastic case with a handle.

Easy to use

We won't try to give you the complete instructions in this blog post, but here's a quick overview to how simple the procedure is.

It starts with a piece of tubing, squarely cut and properly deburred. For smaller tubing, slip a chamfer block over the edge and give it a firm rap with a hammer. That will make sure the tubing fully bottoms in the preswaging tool.

Use the pliers to remove the retaining ring in the end of the hydraulic housing. Slip on a new die that's the right size for the tubing (you can find the sizes marked at the back of the die head). A groove on the outside of the die head will line up with a pin inside the housing. Use the pliers to reinsert the retaining ring.

Now it's time to get out the prepared tube and its corresponding fitting. Insert the tube into the fitting, back the nut off and place the fitting body to the side. Make sure both the front and back ferrules are pointed toward the end of the tube. Then insert the tubing with the nut and ferrule assembly into the hydraulic housing head. Close the nut onto the head, finger tight.

At the back of the hydraulic housing is an indicator knob with a green band. Press that knob into the head until the green band is hidden.

Now it's time to get pumping. Tighten the pump bypass valve and pump until the indicator knob pops back out. When that happens, stop pumping immediately, even if you are in mid-stroke. When you loosen the bypass valve, you'll be able to put the handle back to its original position.

Putting it all together

Before continuing, mark the tubing at the back end of the nut. You'll need that mark later. Unthread the Swagelok nut and remove the pre-swaged assembly from the housing. Notice that the ferrules might be able to move slightly, but you shouldn't be able to remove them.

On the end of the tubing you should see an indentation that indicates that the tubing was properly bottomed. This is critical, so don't use the assembly if the indentation isn't there.

Now you are ready to insert the pre-swaged assembly into the fitting body. (For fittings larger than an inch, or 25mm, you'll need some lubricant for this part.) Turn the nut onto the fitting body until it is finger tight. The line marked on the tubing earlier should now be visible. If you can't see it, tighten the nut with wrench until you can see the mark.

Now mark the nut at the 6 o'clock position. Tighten the nut a half-turn so that the mark is at the 12 o' clock position — a little less for 3/4-inch tubing.

To check your work, pick the right gapping tool out of the kit and put it next to the gap between the nut and the body hex. If the gauge fits into the gap, the fitting isn't tight enough.

If anything goes awry during this process, there's a page of troubleshooting tips in the PDF version of the instructions. And, of course, there's always someone at Swagelok Northern California to talk to by email or phone.

Now that you have the basics, talk to us about buying or renting a multihead hydraulic swaging unit and getting more productive. 


What's next: Get Swagelok literature on our measurement devices, then get in touch for local help with choosing the right components for your application:

Browse tools and tubing›  Download Swagelok Tube Fittings Catalog › 

Help me choose ›

(Prefer to talk live? Please give us a call at 510-933-6200.)

More on this topic:

Topics:ToolsTipsFittingsBest Practices

We perform under pressure

Your fluid systems can't fail—and they can't leak. That's why Swagelok Northern California offers mission critical solutions for the petrochem, semi, power, and oil and gas industries around the Bay Area and into NW Nevada. We manufacture and assemble reliable, customizable components that get the job done. Contact our team today to learn about custom solutions for your plant or refinery.

Swagelok Northern California
Fremont headquarters

3393 W Warren Ave
Fremont, CA 94538
Main tel: 510-933-6200
Email: Message us

Areas served by our fluid systems engineering company