Cryogenic Globe Valve OS Y BB Extend Rising Stem Conical Plug Type
Disc
| Size: | NPS 1/2"~12" |
| Pressure Rating: | Class 150~800 |
| Material: | LCB, LCC, CF8, CF8M, LC3, LF2, LF3, F304, F316 |
| Design & Manufacturing Standard: | BS 1873 ,ASME B16.34, AOU602, BS 5352 |
| Face to Face: | ASME B16.5, EN558 |
| Flanged Dimenson: | ASME B16.5(BSEN 1092) |
| Butt Weld Dimensin: | ASME B16.25 |
| Threaded end Dimension: | ASME B1.20.1 |
| Socketweld dimension: | ASME B16.11 |
| Test and Inspection: | API 598, BS 6364 |
| Operation Method: | Manual ,Worm Gear, Electric Actuator,
Pneumatic Actuator |
APPLICATION & FUNCTION
Globe valves are primarily used as control valves where throttling
or both throttling and shut-off are required. Globe valves can also
be used for on-off service; however, because of the design, a
pressure drop becomes inherent. This is generally confined to
on-off applications where the valve is normally closed and pressure
drop is not important when the valve is open. Normal applications
will find the globe valve with the flow and
pressure under the disc. cast steel globe valves are commonly made
in outside screw and yoke designs with full ports (including seat
ring) and heavy-duty, conical plug type discs.
BODY & BONNET
The body is full ported and spherical in form. The design utilizes
large radiuses which allow for the stresses, flow resistance and
turbulence to be kept to a minimum. Valve bonnets are equipped with
a backseat bushing.
DISC
The valve is normally supplied with the conical plug type disc. The
disc rotates freely on the stem and incorporates a differential
angle from that on the seat ring. This design provides the maximum
assurance of shut off, is less likely to stick in the body seat,
and is considered the simplest design for field repair. The disc is
held onto the stem utilizing the disc nut and a split-ring disc
retainer on 2”–4” in pressure classes 150 and 300.
Larger sizes as well as pressure classes 600 and higher utilize the
disc nut and a button head design which is integral with the stem.
Bottom guided discs are available.
SEAT RINGS
Seat rings are designed to greatly reduce and/or prevent any
turbulence and avoid damages due to corrosion. The seat rings are
forged or rolled in one piece and then seal welded and overlaid, if
required. After welding and all required heat treating, the seat
ring faces are machined, thoroughly cleaned and inspected before
leaving for assembly.
STEM
As standard, all stems are rotating and rising; however, a
non-rotating design is available when specified by the customer.
The accuracy in the dimensions and finishes assure a long life with
a perfect tightness in the packing area, resulting in lower
fugitive emissions. All of our stems are designed with integral
backseat features which provide an ultimate seal during packing
changes.
STUFFING BOX
The depth of the stuffing box allows for a sufficient amount of
packing, which makes the stem seal. GWC’s standard packing
arrangement and stuffing box design meets<100 ppm fugitive
emission requirements. If specified in the purchase order, lantern
rings and/or grease injectors can be
furnished.
STEM PACKING
The stem packing is designed and arranged to ensure a maximum seal
along the stem during operation or while at position, thus allowing
for a greater reduction in fugitive emissions. Our packings are of
nonasbestos types.
Valve can supply any style of packing required by the customer.
PACKING GLAND
The packing gland design is a two-piece self-aligning type. The
packing gland has a spherical head that rides within the spherical
joint of the gland flange. The packing gland has a shoulder, which
restricts the complete entry into the stuffing box bore. This
particular design assures a straight compression of the packing as
the gland eyebolts are being equally adjusted, without injuring the
stem.
STEM NUT
The stem nuts on standard rising stem globe valves are threaded
into the top of the yoke where they are secured with a ack weld.
OPERATION
Handwheels are designed with a comfortable grip for easy operation.
Our valves are also available with gearing, motor actuators or
cylinder actuators for the more demanding services.
BOLTS AND NUTS
For normal service conditions, ASTM A194 Class 2H and ASTM A193
Grade B7 nuts and stud bolts are furnished. If specified for high
temperature service conditions, ASTM A194 Class 4 and ASTM A193
Grade B16 nuts and stud bolts are furnished. Standard bolting
furnished for our stainless steel valves consists of ASTM A194
Class 8 and ASTM A193 Grade B8 nuts and stud bolts.
Valve can supply any bolting as requested by the customer.
END CONNECTIONS
Our standard production covers valves with:
• Flange ends with Raised Face (RF), Flat Face (FF) or Ring Type
Joint (RTJ) that conform to B16.5.
• Butt-welding ends (BW) that conform to B16.25.
• All face-to-face/end-to-end dimensions conform to B16.10.
• Other special end connections are supplied according to
customer’s requirements.
ACCESSORIES
Accessories such as gear operators, actuators, bypasses, locking
devices, chainwheels, extended stems and bonnets for cryogenic
service and many others are available to meet the customers
requirements.
