4'' 150LB WCB Galvanized Manually Flange end Globe Valve
Quick Details
How Does It Work?
Globe valves are usually controlled by an automatic actuator that
regulates the flow by moving the
disk perpendicular to the seat. Globe valves can control fluid flow
either manually or automatically.
The right angles produce less leakage than you’d find in a gate
valve.
When turned in a clockwise motion the disk lowers to the seat which
physically obstructs the
liquid’s path, either reducing it or blocking it completely,
depending on how low the disk moves.
Parts of a Globe Valve
A globe valve has several key parts:
Bonnet: The bonnet is the outer part of the valve, which
encompasses these other parts.
Cage: The cage surrounds the stem within the valve.
Stem: The stem connects the disk to the valve actuator or
handwheel, transmitting the force.
Disk (Plug): The part of the globe valve that moves perpendicular
to the seat. It’s the moveable
physical barrier that blocks (or frees) the flow.
When closed, the disk sits against the seat, plugging the flow.
When opened, the disk sits above the
seat, allowing liquid to pass.
Seat (Seat ring): This part of the valve provides the seal between
the stem/disk and bonnet when
the disk is tightly pressed against it. It’s either integrated or
screwed into the valve itself.
| SPECIFICATIONS FOR STEEL GLOBE VALVES |
| Pressure rating and size: | PN10,PN25,PN40,PN64,150L-600LB |
| DN40 to DN600 |
| 1-1/2"~24" |
| Material: | Body : A216-WCB,A325-LCB,A217-WC6,CF8,CF8M |
| Disc : A105+13Cr, SS304, SS316 |
| Stem : A182+F6a,A182-F6a |
| Bonnet :A216-WCB,A325-LCB,A217-WC6,CF8,CF8M |
| Operated type | Handwheel |
| Structure: | stopcock for water |
| Flange connection: | ASME B16.5,EN1092 |
| Butt-weld ends: | ASME B16.25 |
| Medium: | W.O.G |
| Temperature: | -20 to 425°C |
Globe valves
A Globe valves is a linear motion valve and are primarily designed
to stop, start and regulate flow.
The disk of a Globe valve can be totally removed from the flowpath
or it can completely close the flowpath.
Conventional Globe valves may be used for isolation and throttling
services. Although these valves exhibit slightly
higher pressure drops than straight=through valves (e.g., gate,
plug, ball, etc.), they may be used where the pressure
drop through the valve is not a controlling factor.
Because the entire system pressure exerted on the disc is
transferred to the valve stem, the practical size limit for these
valves is NPS 12 (DN 300). Globe valves larger than NPS 12 (DN 300)
are an exception rather than the rule. Larger
valves would require that enormous forces be exerted on the stem to
open or close the valve under pressure. Globe
valves in sizes up to NPS 48 (DN 1200) have been manufactured and used.
Globe valves are extensively employed to control flow. The range of
flow control, pressure drop, and duty must be
considered in the design of the valve to avert premature failure
and to assure satisfactory service. Valves subjected
to high-differential pressure-throttling service require specially
designed valve trim.
Generally the maximum differential pressure across the valve disc
should not exceed 20 percent of the maximum
upstream pressure or 200 psi (1380 kPa), whichever is less. Valves
with special trim may be designed for applications
exceeding these differential pressure limits.
| SIZE | d | L | H | W | D | C | G | T | N-ΦM |
| 1" | 25 | 127 | 212 | 140 | 108 | 79.5 | 51 | 11.1 | 4-16 |
| 1 1/4" | 32 | 140 | 243 | 160 | 117 | 89.5 | 64 | 12.7 | 4-16 |
| 1 1/2" | 40 | 165 | 246 | 160 | 127 | 98.5 | 73 | 14.3 | 4-16 |
| 2" | 50 | 203 | 252 | 200 | 152 | 120.5 | 92 | 15.9 | 4-19 |
| 2 1/2" | 65 | 216 | 308 | 200 | 178 | 139.5 | 105 | 17.5 | 4-19 |
| 3" | 80 | 241 | 327 | 250 | 190 | 152.5 | 127 | 19.1 | 4-19 |
| 4" | 100 | 292 | 384 | 250 | 229 | 190.5 | 157 | 23.9 | 8-19 |
| 5" | 125 | 356 | 484 | 300 | 254 | 216 | 186 | 23.9 | 8-22 |
| 6" | 150 | 406 | 547 | 350 | 279 | 241.5 | 216 | 25.4 | 8-22 |
| 8" | 200 | 495 | 669 | 350 | 343 | 298.5 | 270 | 28.6 | 8-22 |
| 10" | 250 | 622 | 824 | 200 | 406 | 362.5 | 324 | 30.2 | 12-25 |
Advantages and disadvantages of Globe valves
ADVANTAGES:
- Good shutoff capability
- Moderate to good throttling capability
- Shorter stroke (compared to a gate valve)
- Available in tee, wye, and angle patterns, each offering unique
capabilities
- Easy to machine or resurface the seats
- With disc not attached to the stem, valve can be used as a
stop-check valve
DISADVANTAGES:
- Higher pressure drop (compared to a gate valve)
- Requires greater force or a larger actuator to seat the valve (with
pressure under the seat)
- Throttling flow under the seat and shutoff flow over the seat
