DN40 (1-1/2″) Class 200 ASTM A351 CF8M NPT Threaded Globe Valve GL029902

When you’re shopping for a globe valve manufacturer, the certifications they hold tell you a lot about their quality standards and what they’re capable of producing. Here’s a quick breakdown of what to look for:

On the design side, you want to see API 623 — that’s the heavy-duty bolted bonnet steel globe valve standard for petroleum refineries and related applications. You’ll also commonly see BS 1873 (the British standard for steel globe and check valves), along with ASME B16.34 which covers valves with flanged, threaded, and welding ends.

For testing, API 598 is the go-to standard for valve inspection and testing.

If you’re working with sour service (meaning H₂S environments), look for NACE MR0175 compliance — that’s non-negotiable for safety in those conditions.

For quality management, ISO 9001 is pretty much table stakes these days.

And if you’re shipping to Europe, you’ll need CE marking and PED compliance.

Just so you know, API 623 covers valves from NPS 2 through 24 (DN 50 to 600) and pressure classes 150 through 2500. A manufacturer that meets these standards has the know-how to produce valves with heavy wall sections and large stem diameters for the most demanding jobs out there.

Like any mechanical component, globe valves can run into issues over time. Here are the ones we see most often:

Leakage — This can happen at the body, the stem, or the seat. Usually it’s caused by wear on the sealing surfaces, aging gaskets, or a bent valve stem. The fix is pretty straightforward: replace the sealing surface or gasket, and check the stem for straightness.

Sticking — After a long period of use, the valve might get stuck and refuse to open or close properly. This is often due to scale buildup, debris accumulation, or not enough lubrication. A good cleaning and a proper lubrication schedule usually take care of it.

Stiff operation — If turning the handwheel feels harder than it should, you could be dealing with a bent stem, internal scaling, or poor lubrication again. Check the stem first and keep up with regular maintenance.

Stem or packing leakage — This one’s usually an easy fix. Just check the packing nut and gland bolts — they might have loosened up. Give them a snug (but not over-tight) turn and you’re good to go.

One golden rule: never, ever exceed the valve’s maximum pressure rating during operation. That’s a fast track to bigger problems.

In plain English, Cv is a number that tells you how much flow a valve can pass. More technically, it’s the number of US gallons per minute of 60°F water that can flow through a fully open valve with a 1 psi pressure drop. So if a valve has a Cv of 100, it means 100 gallons per minute of water will pass through with just 1 psi of pressure loss.

Here’s why this matters: Cv is the single most important number when you’re sizing a control valve. It tells you whether the valve is big enough to handle your required flow given the pressure drop you have available.

Now, a heads-up — globe valves have the lowest Cv per size compared to other valve types because of that S-shaped flow path we mentioned earlier. Just to give you a rough idea:

• A 2-inch globe valve has a Cv around 30

• A 4-inch globe valve is roughly 110

• A 6-inch comes in around 210

• And an 8-inch is about 340

If you want to do the math yourself, the basic formula for liquid flow is: Cv = Q × √(G / ΔP), where Q is flow rate in GPM, G is specific gravity (water = 1.0), and ΔP is pressure drop in psi. Not a fan of formulas? No problem — just tell us your conditions and we’ll help you size it.

Choosing the right globe valve comes down to asking yourself a few key questions about your system. Here’s what we usually walk our customers through:

First, what’s the job? Are you mainly throttling flow, or is it more of an on-off application? That’ll point you in the right direction. Next, you need to look at your flow rate and how much pressure drop your system can afford — that’s where the Cv value comes in (more on that in the next question). Then consider what’s actually flowing through the pipe. Is it clean water or steam? Oil or gas? Or is it something more aggressive? Just keep in mind that globe valves generally aren’t a good fit for slurries or fluids with suspended solids.

You’ll also need to think about your temperature and pressure — make sure they fall within the valve’s P-T rating per ASME B16.34. And don’t forget the physical stuff: do you need a straight pattern, a Y-pattern (which has lower flow resistance), or an angle pattern for a 90-degree turn? What about end connections — flanged, threaded, or welded? And which disc type makes sense for your level of throttling precision? Take all of this into account, and you’ll land on the right choice.

Yes, it absolutely does, and this is something you really don’t want to get wrong. Globe valves are unidirectional, which means they’re designed to allow flow in only one direction. On most valves, you’ll find an arrow cast right into the body — that’s your guide. If you can’t see it, you can also peek into one end of the valve and check whether you’re looking at the underside of the seat or above it. The standard setup is typically “low in, high out” — meaning the flow comes in from under the disc.

If you install it backwards, you’re asking for trouble. You’ll get increased stem packing wear, higher operating torque, potential seat leakage, and a shorter service life overall. So our advice? Always check that arrow before you bolt it into place. It takes two seconds and saves you a whole lot of headaches later.

This is probably one of the most common questions we get, and the short answer is: they’re built for completely different jobs. A gate valve is like an on-off switch — you either open it all the way or close it completely. If you try to use it for throttling, you’ll run into trouble fast because the partially open gate and seats get chewed up by high-velocity flow, causing what we call “wire drawing” erosion. In a matter of weeks or months, the valve could fail. A globe valve, on the other hand, is more like a dimmer switch — it’s happy to hold any position in between to regulate flow.

There are a few other differences worth noting. Gate valves have a straight-through bore so the pressure drop is very low, while globe valves have an S-shaped flow path that creates more resistance. Globe valves are also unidirectional — you’ll see an arrow on the body showing which way the flow should go — whereas gate valves work in either direction. And for the same size and pressure rating, globe valves tend to be heavier because they use more metal in the body. Design standards are different too: gate valves usually follow API 600, while globe valves are covered under API 623 or BS 1873.

If you’re looking for a valve that can do more than just turn flow on and off, a globe valve is probably what you need. It’s designed specifically for throttling — meaning you can adjust the flow rate by turning the handwheel and controlling how far the disc lifts off the seat. That vertical up-and-down movement gives you pretty precise control over the flow, which is why you’ll find these valves everywhere in steam systems, cooling water circuits, boiler feedwater lines, and chemical dosing applications. They’re also great for bypass lines and can handle high-pressure, high-temperature conditions without breaking a sweat. So if your system needs frequent flow adjustments, a globe valve is the way to go.