How to Identify Gate Valve and Globe Valve

As an experienced engineer working with industrial valves, I often get asked how to tell gate valves and globe valves apart. These two common valve types may look similar at first glance, but each has distinct features suited for different applications.

In this complete guide, I’ll walk you through the key differences between gate and globe valves, as well as tips for visually identifying them. Whether you’re a plant manager, maintenance technician, or valve supplier, understanding gate valve vs globe valve basics is essential knowledge. So let’s dive in!

Why Properly Identifying Valves Matters

Being able to accurately identify gate and globe valves in piping systems is important for several reasons:

• Avoid Misoperation – Operating the wrong valve by mistake could lead to process disruptions, equipment damage, or even worker injuries.
• Facilitate Maintenance – Correctly naming valves enables the maintenance team to quickly isolate and repair issues. No more chasing obscure valve references!
• Simplify Communication – Unified valve identification allows departments to collaborate smoothly when discussing flow control.
• Prevent Misordering – Ensuring you have the right replacement valve helps prevent improper installations and wasted time.

In short, taking the time to properly ID these valves makes system control safer and equipment maintenance quicker for your facility.

Key Differences Between Gate and Globe Valves

Despite some visual similarities, gate and globe valves have significant internal differences that make each better suited for certain applications.

Here’s an overview of how they differ:

Feature	Gate Valve	Globe Valve
Main Function	Isolating flow	Throttling flow
Flow Regulation	Only fully-open or closed	Variably controls flow rate
Pressure Drop	Very low	High
Typical Shape	Rectangular	Round body
Flow Direction	Bidirectional	Unidirectional
Sealing Capability	Moderate	Excellent
Applications	On/off service, sewage	Metering, mixing, cooling lines

So in summary:

• Gate valves – Simple on/off control but can’t throttle. Bidirectional flow and minimal pressure loss when open.
• Globe valves – Allow finer flow control regulation. Unidirectional flow and larger pressure drops.

With the basics covered, let’s look at visual cues for identifying installed gate and globe valves quickly.

How to Identify Gate Valve and Globe Valve

How to Identify a Gate Valve Visually

Follow these tips for conclusively distinguishing a gate valve by sight:

1. Check for Rectangular Body Shape

Gate valves have an unmistakable rectangular or squared-off body shape containing the movable gate plate inside. Globe valves may appear more rounded.

2. Turn the Handwheel and Observe Stem Movement

Most gate valves have a rising stem design. As you turn the handwheel to open the valve, you’ll see the threaded valve stem rise up through the stuffing box.

If the stem moves up and down as you operate it, it’s definitely a gate valve rather than a globe which would only see rotational stem movement.

3. Examine the Gate Plate Design

Fully open the valve if possible and look inside to spot the large gate plate. Gate valves contain either a solid wedge or parallel sliding gate that moves at right angles across the body to stop flow.

If you spot these distinctive gates, it’s a surefire confirmation that the valve is a gate type.

4. Note Overall Height and Size

Fully-open gate valves tend to have greater heights than globe valves. This matches their movement pattern with rising stems that extend upwards as they open.

Gate valves also occupy less space from end-to-end since their inlet-outlet ports align directly without redirection.

If the valve is relatively tall and compact lengthwise when open, it points to a gate valve unit.

Tips for Spotting Globe Valves

Here are handy visual methods to recognize globe valves:

1. Identify the Round Body Shape

Globe valve bodies have a very rounded form compared to the square bodies found on gate types. This spherical shape matches their name and is a strong initial indicator.

2. Turn Stem and Feel Resistance

Globe valves use rotational stem motions rather than rising-stems. When you turn a globe valve handwheel, you’ll feel consistent resistance as the plug moves closer or farther from the seat.

No up and down stem motion takes place. The valve closes gradually rather than abruptly shutting flow entirely.

3. Check for External Flow Arrows

Globe valves only allow one-way flow, so manufacturers mark the exterior valve body with directional arrows indicating which way media passes through.

Gate valves lack these unidirectional flow arrows since their bidirectional design permits media to pass both ways through the valve.

4. Confirm Space Requirements

Globe valves need extra horizontal room for installation compared to gate valves since they redirect flow using right-angled elbows inside the body.

Expect globe valves to occupy more space from end-to-end. Their height when open is also typically less than gate valves.

By visually inspecting body shape, stem movement, flow arrows, and size, you can reliably differentiate globe valves from gate types even at a glance.

Pro Tip: Reference the Valve Data Plate

For absolute certainty, check the metal nameplate on the valve body showing manufacturer, model number, size, pressure class, serial number, and other specifics.

Cross-reference markings like “Gate Valve Cast Steel Class 800” or “Globe Valve SS Class 150” with online valve spec sheets to eliminate any doubts.

Correct identification is crucial, so use these visual and written cues to confidently distinguish gate valves from globe types. Feel free to contact us if you have any other valve ID questions!

How Not to Mix Up Gate and Globe Valves

Now that we’ve covered reliable methods for identifying gate and globe valves properly, let’s also touch on common mix-ups:

Mistake #1: Assuming all valves with handwheels are gate types.

Why it’s wrong: Both gate and globe valves utilize handwheel actuators. The stem movement differs.

Mistake #2: Believing all small valves are globe types.

Why it’s wrong: Size does not indicate valve type. Both come in ranges from 1⁄2″ to 30″+.

Mistake #3: Thinking valves with flow direction arrows are all gate types.

Why it’s wrong: Only globe valves need unidirectional flow arrows. Gate valves permit bidirectional flow.

Avoid these misconceptions, and use the identification best practices we covered instead to accurately spot gate and globe valves.

Maximizing Valve Life and Performance

Now that you can reliably tell gate and globe valves apart:

• Gate Valves – Fully open or close them during operation. Never throttle flow using partial openings.
• Globe Valves – Turn handwheels smoothly and avoid sudden motions or over-tightening.

Following manufacturer guidance for installing, operating, and maintaining each valve type correctly will maximize their lifetime value.

Final Thoughts

Identifying installed valves seems easy…until you’re staring at an unmarked jumble of pipes and can’t tell gate and globe valves apart.

Use this guide to visually inspect key indicators like body shape, stem movement, flow arrows, and size differences. Cross-check markings on nameplates forcertainty.

Correctly distinguishing gate from globe valves saves headaches when isolating, replacing, or controlling flow in piping systems. Share this article with technicians struggling to ID these common yet confused valve types confidently!

Still have questions? Ask in the comments section below!