What is Gate Valve?
A gate valve can be defined as a type of valve that used a gate or
wedge type disk and the disk moves perpendicular to flow to start
or stop the fluid flow in piping.
A gate valve is the most common type of valve used in any process
plant. It is a linear motion valve used to start or stop fluid
flow. In service, these valves are either in a fully open or fully
closed position.
When the gate valve is fully open, the disk of a gate valve is
completely removed from the flow. Therefore virtually no resistance
to flow. Due to this very little pressure drops when fluid passes
through a gate valve.
To achieve proper sealing, when the valve is fully closed, 360°
surface contact is required between disk and seats.
Gate valves should not be used for regulation or throttling of flow
because accurate control is not possible.
The high velocity of the flow in the partially open valve may cause
erosion of the disc and seating surfaces
and also creates vibration and noise.
Resilient Seated Gate valve, Handwheel operated, ductile iron body
(FBE coated internally/externally),
flanged ends to AS4087 B5 (AS2129 Table D) class 16- approved to
AS2638.2
Sizes 2″ → 16″ (DN50→ DN400)
* Options: Key adaptor, Gearbox, ISO mounting flange for actuation
Valve Type | CS / SS GATE VALVE - FL / BW |
Design Std | BS EN ISO 10434 [BS 1414] / API 600 / API 602 / API 603/ASME B16.34 |
Size Range | 40 DN to 400 DN [1 1/2” to 16”] |
Body | [CS - ASTM A 216 Gr. WCB] [SS - ASTM A 351 Gr.CF8 / CF8M] |
Trim | AISI 410 / 304 / 316 |
Seat / Wedge | 13% Cr. Steel / AISI 410 / 304 / 316 |
Design Features | Bolted Bonnet, OS & YT, HW & Gear operated |
Prorating | ASME - Class 150 / 300 / 600 |
Face to Face | ASME B 16.10 / EN 558 -1 / API 6D |
End Connection | Flanged | ASME B16.5, CLASS 150 / 300 / 600 |
Butt weld | ASME B16.25 |
Testing Std. | BS EN 12266 - 1 [BS 6755-1] / API 598 |
Optional | Lantern Ring / indicator & Locking Device/ Renewable Seat /
Stellite Hard facing / Jacketed Provision / RTJ Flanges / By Pass
Arrangement / Higher Sizes / Special MOC: Austenitic and Duplex
Stainless Steels |
Types of Gate Valves
There are three ways to classify the gate valve.
Types of Disk
Solid taper wedge
Flexible wedge
Split wedge or Parallel disks Valve
Types of Body Bonnet Joint
Screwed Bonnet
Bolted-Bonnet
Welded-Bonnet
Pressure-Seal Bonnet
Types of Stem movement
Rising Stem or OS & Y Type (Outside Stem and Screw Type)
Non-rising Stem type
Gate Valve Applications
Gate valves are used in almost all fluid services such as air, fuel
gas, feedwater, steam, lube oil, hydrocarbon, and all most any
services.
Some special gate valve is used in slurry and powder product also
such as knife gate valve
Advantages of Gate Valve
Gate valve provides good
Pressure drop during operation is very less.
Most of the gate valve can be used as bi-directional
They are suitable for high pressure and temperature application and
required less maintenance
Use:
For water, sewage and neutral liquid applications Valve designed
for use up to 70°C Where applicable;
AS 4020 compliance, max temp = 40°C Note: Always observe pipe
material recommended operating temperatures
Materials:
Gland flange, Ductile iron, 500-7 to AS 1831 body and bonnet
Coating Fusion bonded epoxy resin - Internally and externally to AS
4158
Stem Stainless steel 431
Stem sealing NBR wiper ring, 2 NBR O-rings
Wedge Ductile iron, 500-7 to AS 1831, core fully vulcanised with
EPDM rubber, with integral wedge nut of
dezincification resistant brass, CZ 132 to AS 2345
Bushing Polyamide
Thrust collar and Dezincification resistant brass, stem seal box CZ
132 to AS 2345
Bonnet bolts DN50 - DN250 Stainless steel 304, sealed with hot melt
DN300 - DN400 Grade 12.9, sealed with hot melt
Gland flange Stainless steel 316 bolts
Bonnet gasket EPDM rubber
Handwheel Ductile iron to AS 1831
Tests:
Hydraulic test to AS 2638.2: Seat: 16 bar Body: 24 bar Operating
torque test
Optional extras:
Stem cap Flange gasket kits ISO flanging for actuation Gearbox User
specified flange drilling
