Tube Fitting Installation Training & Education
Tube fitting installation training is the body of knowledge for correctly making up, gauging, remaking, selecting, and troubleshooting instrumentation compression tube fittings, valves, and tubing. This hub curates Crestflo's how-to guides and videos into one place to learn the pull-up-by-turns make-up method, gap-gauge inspection, and alloy-aware fitting selection, then routes you to the specs, samples, and support you need.
This training covers instrumentation compression tube fittings, valves, and tubing for fluid systems in stainless and high-alloy service, not automotive brake or fuel lines, plumbing compression fittings, or electrical wire ferrules.
The training is free, self-serve, and built as HTML you can read on any device, no login, no gated course. It is written by the manufacturer of the fittings it teaches, so the method reflects real double- and single-ferrule hardware qualified to ASTM F1387.
Also Called Fitter Training, Make-Up Training or Instrumentation Fitting Essentials
Specifiers and field crews name this same discipline many ways. It is variously called tube fitting training, tube fitting installation course, instrumentation fitter training, installer training, ferrule installation training, fitting make-up training, or compression fitting installation. The core teaching, "pull-up by turns," the 1-1/4 turn make-up, gap-inspection gauging, and turns-not-torque assembly, is the same practice whether a program is labeled a tube fitting installation class, an instrumentation training course, an installation essentials course, or on-the-job fitter training. Adjacent topics people group with it include tube bending training (also searched as tubing bending training) and tube fitting selection, both routed below to their owning guides.
What This Tube Fitting Installation Training Covers: The Curriculum Map
The curriculum is organized into modules. Each module summarizes the essentials here and links to the guide that owns the deep procedure, so you can go as far as you need.
| Module | What you'll learn | Guide |
|---|---|---|
| Make-up & pull-up | Bottom the tube, finger-tight, pull up by counted turns, ferrule action | Ferrule installation & gauging |
| Gauging & inspection | Gap-inspection gauge use; confirm pull-up before pressurizing | Ferrule installation & gauging |
| Remaking & reassembly | Reconnect and remake a fitting without over-pulling | Ferrule installation & gauging |
| Valve installation & selection | Install and choose needle, ball & manifold valves; when to use each | Needle valve · Ball valve · Needle vs ball valve |
| Manifold installation & mounting | Mount 2-, 3- and 5-valve manifolds close-coupled to the instrument | 2-valve manifold · 3-valve · 5-valve |
| Ferrule design choice | Single vs double ferrule; hardened vs non-hardened | Single vs double ferrule · Hardened vs non-hardened |
| Tube sizing | Tube OD, wall thickness, and pressure selection | Tube sizing & wall thickness |
| Thread identification | NPT, BSPT, BSPP, ISO parallel, identify before make-up | Thread identification guide · NPT vs NPTF |
| Alloy selection | Match alloy to chloride, sour, cryogenic, and high-purity service | Material selection by service · Sour service / NACE |
| Pressure & temperature | Derate ratings for temperature | Pressure–temperature derating |
| Seal selection | Elastomer and packing temperature limits | Seal material temperature selection |
| Troubleshooting | Diagnose leaks and make-up errors | Troubleshooting |
| Brand interchange | Safe interchange on an F1387 basis | Mixing tube fitting brands |
| Reference | Symbols and terminology | Valve symbols · Glossary |
| Video | Watch make-up and gauging demonstrations | Videos |
The products the training applies to, unions, elbows, tees, connectors and more, are cataloged under tube fittings, with instrumentation valves and tubing covered in their own ranges.
How to Make Up an Instrumentation Tube Fitting: Pull-Up by Turns, Not Torque
How to install tube fittings, and how to install compression fittings of the instrumentation type, comes down to one repeatable method: pull-up by counted turns. A double-ferrule instrumentation fitting is made up by counted turns of the nut from finger-tight, never to a torque value. Counted turns give a repeatable ferrule advance regardless of thread friction, so grip and seal are consistent from joint to joint. The standard published method is:
- Prepare the tube. Cut it square, deburr the inside and outside diameters, and wipe it clean. Use the correct tube OD and wall for the fitting series and service pressure.
- Bottom the tube. Insert it fully into the fitting body until it seats on the internal shoulder. A tube that is not bottomed is the most common cause of a joint that will not seal.
- Finger-tighten the nut onto the body, then scribe a witness mark so the turn count is unambiguous.
- Pull up by turns. Hold the body with a backup wrench and pull the nut up 1-1/4 turns past finger-tight for 1/4" (6 mm) tube and larger, or 3/4 turn for 3/16" (5 mm) and smaller.
- Gauge the make-up before pressurizing (see below).
Pull-Up by Tube OD: The 1-1/4 Turn Rule & 3/4 Turn for Small Tube
| Tube OD (imperial) | Tube OD (metric) | Pull-up past finger-tight (standard method) |
|---|---|---|
| 1/16" – 3/16" | ~1.6 – 5 mm | 3/4 turn |
| 1/4" | 6 mm | 1-1/4 turns |
| 3/8" | 8–10 mm | 1-1/4 turns |
| 1/2" | 12 mm | 1-1/4 turns |
| 5/8" – 3/4" | 16–20 mm | 1-1/4 turns |
| 1" – 2" | 25–50 mm | 1-1/4 turns |
Values shown are the standard published industry make-up method for two-ferrule fittings; they are per the applicable standard and customizable to the fitting series. Single-ferrule designs follow the pull-up specified for that series, see single vs double ferrule. For the exact turns certified for a specific Crestflo part number, request the ordering-code and make-up reference from our engineering team. Full step-by-step detail lives in the ferrule installation & gauging guide.
Gauging & Inspection: Confirming a Correct Tube Fitting Make-Up
After pull-up and before you pressurize, verify the joint with a gap-inspection gauge sized to the fitting. Place the no-go gauge at the gap between the nut and the body: if the gauge will not enter the gap, the fitting is sufficiently pulled up. The gauge is for initial installation, giving a fast, objective check that a joint was made up correctly without relying on feel. Full technique, including what to do if a gauge enters the gap, is in the ferrule installation & gauging guide.
Remaking & Reusing Tube Fittings
Instrumentation tube fittings can be disconnected and remade. Once the ferrules are swaged, they stay permanently on the tube, so you reuse that tube-and-ferrule assembly. On reassembly, insert the tube with its pre-swaged ferrules back into the body, thread the nut to the previously made-up position, then snug it with a slight additional rotation, you do not repeat the original full pull-up. Two-ferrule designs support repeated remakes; the procedure is detailed in the ferrule installation & gauging guide.
Selecting the Right Fitting, Alloy, Thread & Seal
Correct installation only holds if the fitting was correctly selected. This is where alloy-aware training separates a durable joint from a premature failure. Route each selection decision to its guide:
| Decision | Guide |
|---|---|
| Tube OD and wall thickness | Tube sizing & wall thickness |
| Thread type (NPT, BSP, ISO parallel) | Thread identification guide · NPT vs BSP |
| Alloy by service | Material selection by service |
| Sour / NACE service | Sour service selection (NACE) |
| Pressure–temperature derating | Pressure–temperature derating |
| Seal / elastomer temperature | Seal material temperature selection |
| Single vs double ferrule | Single vs double ferrule |
| Metric vs imperial | Metric vs imperial tube fittings |
| Full specification workflow | How to specify fittings & valves |
The make-up method is alloy-independent, but ferrule hardness and pull-up feel vary by tube alloy. Crestflo offers hardened and non-hardened ferrules to requirement, harder alloy tube (Duplex, Super Duplex, 254 SMO, nickel alloys, Titanium Grade 2) typically calls for a hardened ferrule for reliable grip. For high-purity and oxygen service, follow the applicable cleaning and handling practice covered under oxygen and UHP cleaning.
Troubleshooting Leaks & Mixing Tube Fitting Brands
Most field leaks trace to a small set of make-up errors: a tube that was not bottomed, under- or over-pull-up, a mis-cut or burred tube, cross-threaded pipe threads on the body, the wrong ferrule or size, or reversed ferrules. Diagnose them with the troubleshooting guide.
On interchange: Crestflo double-ferrule fittings are qualified to ASTM F1387 and follow the same pull-up-by-turns method as major-brand double-ferrule systems, so they interchange as dimensional equivalents in like-for-like sizes. Interchange should always rest on that F1387 performance basis rather than mixing loose components blindly, the mixing tube fitting brands guide explains how to do it safely. Swagelok® is a trademark of Swagelok Company; Crestflo is not affiliated with or endorsed by it.
Do & Don't: Tube Fitting Make-Up Quick Rules
| Do | Don't |
|---|---|
| Make up by counted turns from finger-tight | Torque to a wrench value |
| Bottom the tube fully before pulling up | Pull up a tube that isn't seated |
| Gauge the joint before pressurizing | Pressurize on feel alone |
| Confirm ferrule taper direction | Install ferrules reversed |
| Interchange on a documented F1387 basis | Mix loose brand components without a basis |
Watch: Tube Fitting Installation & Gauging Videos
Prefer to see the make-up and gap-gauge check demonstrated? The video library walks through ferrule installation, pull-up by turns, and gauging so you can pair the written steps with a visual reference before you work on a live system.
Why Train on Crestflo Fittings
Learning on Crestflo hardware means the method matches the part in your hand. Crestflo compression tube fittings are qualified to ASTM F1387 for drop-in interchange, available in single- and double-ferrule designs with hardened and non-hardened ferrules, in imperial and metric sizes to 2" (50 mm) OD. Every part is heat-number marked for full traceability with EN 10204 3.1 material test certificates (3.2 on request), and Crestflo is ISO 9001 / 14001 / 45001 and PED certified. As the instrumentation division of a four-decade-old, Government-of-India-recognized export house, Crestflo pairs manufacturing depth with a small-MOQ, private-label, made-to-print model. Stock and lead time: ready stock for standard items, made-to-order for specials, 6–8 week delivery; Indian origin with US / European melt available on request and full material traceability. Explore the tube fitting range, instrumentation valves, and ferrules. We Engineer Confidence.
Get Installation or Spec Help, a Sample, or a Quote
Need to confirm a make-up detail, select an alloy, or size a fitting for your service? Request installation or spec help, request a quote or a sample, or send a distributor training inquiry through the distributor program. US contact: sales@crestflousa.com · +1 346 594 9005 · Houston, TX.
Frequently Asked Questions
How do you install an instrumentation tube fitting?
Cut the tube square and deburr it, insert it fully to the shoulder in the fitting body, hand-tighten the nut, mark it, then pull up by a set number of turns from finger-tight, the standard method is about 1-1/4 turns for 1/4" (6 mm) tube and larger, and 3/4 turn for smaller, and verify with a gap-inspection gauge before pressurizing. Full steps are in the ferrule installation & gauging guide.
Do you tighten tube fittings by torque or by turns?
By turns from finger-tight, not by torque wrench. Counted turns produce a repeatable ferrule advance regardless of thread friction, so make-up is consistent from joint to joint and is confirmed with a gap-inspection gauge.
How do I check a tube fitting is tightened correctly?
Use a gap-inspection gauge on the assembled fitting before pressurizing. Place the no-go gauge at the gap between the nut and body; if the gauge will not enter the gap, pull-up is sufficient.
Can I take a tube fitting apart and remake it?
Yes. The ferrules stay swaged on the tube, so you reuse that tube-and-ferrule assembly. On reassembly, thread the nut back to its previously made-up position and snug it with a slight additional rotation, a fully seated fitting does not need the original full pull-up again.
Do you offer a tube fitting installation course or training near me?
Crestflo provides free self-serve training online, written guides plus videos, that you can use anywhere, any time. For on-site or instructor-led training tied to a specific project or distributor program, contact our engineering team to discuss what support is available for your requirement.
Is there a PDF, datasheet, or completion certificate?
The training is free, self-serve HTML you read in the browser, there is no gated PDF course, no downloadable installation-instructions PDF, and no installer completion certificate or certified-installer competency program. Product datasheets and CAD are available to customers on request. To confirm a make-up detail for a specific part or get a datasheet, contact our engineering team.
Can I install Crestflo fittings the same way as Swagelok® fittings?
Yes. Crestflo double-ferrule fittings are qualified to ASTM F1387 and follow the same pull-up-by-turns method, so they interchange as dimensional equivalents in like-for-like sizes; always follow Crestflo's installation instructions for your part. Swagelok® is a trademark of Swagelok Company; Crestflo is not affiliated with or endorsed by it. See mixing tube fitting brands.
What are the different types of tube fittings?
Instrumentation tube fittings include compression fittings (single- and double-ferrule), face-seal fittings (VCR/VCO), weld connectors, and pipe-thread adapters, configured as unions, elbows, tees, crosses, connectors, caps, plugs and more. Browse the full range under tube fittings.
Which alloy and size should I select?
Match the alloy to your service, chloride, sour/NACE, cryogenic, or high-purity, and the size to your tube OD, wall, and pressure. Start with material selection by service and tube sizing & wall thickness.
Why is my tube fitting leaking?
Common causes are a tube that was not bottomed, under- or over-pull-up, a mis-cut or burred tube, a cross-threaded connection, the wrong ferrule or size, or mixed components without an interchange basis. Work through the troubleshooting guide to isolate and fix it.
Are single- and double-ferrule fittings installed the same way?
Both use pull-up by turns from finger-tight, but the mechanics differ, a double-ferrule set separates grip and seal across two ferrules, while a single ferrule does both. See single vs double ferrule and hardened vs non-hardened ferrules.
Related Guides & Resources
- Ferrule installation & gauging, the full step-by-step make-up and gap-gauge procedure
- Thread identification guide, identify NPT, BSP, and parallel threads before make-up
- How to specify fittings & valves, the full selection workflow
- Troubleshooting, diagnose leaks and make-up errors
- Videos, watch installation and gauging demonstrations
- Resources hub, the full instrumentation fittings knowledge library