GE V-LOG Brochure

GE Oil & Gas

Masoneilan* Products

V-LOG* Energy Management Trim

Integrated smart engineered
solutions for severe service
applications

• Scalable trim design

• Operational stability

• Precision control

V-LOG* Trim Technology

GE Oil & Gas offers a broad portfolio of Masoneilan* products
consisting of general service and severe service control
valves, actuators, pressure regulators, and valve-mounted
smart instrumentation and accessories – all supported by
an integrated network of sales offices. The breadth of our
offerings enables us to help customers meet the demanding
requirements of process control applications.

Masoneilan* valve solutions, which include leading designs
such as the LincolnLog* liquid letdown control valve, range
from regulators to customized solutions, including the patented
V-LOG* labyrinth trim technology. We offer custom-tailored
solutions configured for control performance, shut-off reliability
and life-cycle cost- effectiveness. Leading product technology
coupled with application expertise are the keys to our ability to
meet customers’ specifications.

Cost-Effective Engineered Solutions

We offer leading microprocessor-based field instrumentation
technology. Award-winning HART communicating SVI* and
FVP* digital positioners help improve your asset’s effectiveness,
resulting in higher returns on investment. By using patented
tuning algorithms that optimize valve control performance, our
digital positioners deliver improved process yields and lower
maintenance cost.

Innovative V-LOG* Design

Our valve design innovation is at the foundation of our
extensive portfolio of field-proven severe service products
configured for the most challenging applications. GE Oil & Gas’
Masoneilan* products have long been benchmarks for severe
service innovation in industries such as power generation,
oil and gas production and liquefied natural gas (LNG).
These industries present many of the toughest control valve
applications, particularly those involving large mass flow rate
and high differential pressure such as compressor anti-surge,
high pressure vents and turbine bypass.

Severe service applications present technical challenges
associated with the high energy of the flow stream. V-LOG*
Energy Management trim meets these challenges, including
the energy-related issues of noise and vibration, and stringent
demands for control performance.

Benefiting from a very scalable trim design architecture,
V-LOG* trim offers a customized solution for a broad set of
severe compressible fluid and liquid applications. Each V-LOG*
trim solution is designed to meet customer requirements
including tight shutoff, fast opening speeds, operational
stability, and precision control over a wide range of operating
conditions.

Flexibility is built into each of GE Oil & Gas’ digital
instrumentation offerings. SVI* II AP and FVP* valve positioners
mount on any control valve actuator and interface effectively
with HART and Foundation Fieldbus distributed control
schemes, respectively (since SVI* is only Hart and FVP* is only
FF).

You can further increase flexibility and functionality with GE’s
smart instrument companion software such as ValVue*, a tool
that monitors real-time device status. In addition, ValvKeep*
valve database management and AMS Snap-on™ asset
management software provide a comprehensive view into
valve asset maintenance history and performance trends.
These software support tools, in conjunction with the advanced
diagnostic capabilities of smart devices, help significantly
reduce operating costs.

V-LOG* Trim Stack

2 | GE Oil & Gas

Energy Management Principles

3-Dimensional Tortuous Path Flow

The three-dimensional tortuous path design of GE Oil & Gas’
Masoneilan V-LOG* trim controls pressure reduction through the
management of process fluid energy. This is accomplished by
directing the fluid through discrete flow channels which alternate
across two adjacent planes to create a labyrinth effect. These
flow channels contain multiple stages defined by 90 degree turns
with intermediate contractions and expansions in the flow path.

Staged Pressure Drop

The labyrinth flow path of the V-LOG* trim subjects the gas to a
high level of friction as it is redirected through each turn in the
flow path. V-LOG* trim’s patented flow contractions produce
predictable and repeatable flow resistance that differentiates its
design and performance from competing products. The V-LOG*
trim’s design offers a unique flow path shape which maximizes
valve efficiency and performance versus more traditional
tortuous path trim technologies.

The enhanced flow geometry of the V-LOG* trim creates a series
of kinetic energy losses followed by partial energy recoveries at
each stage. The staged reduction of the fluid pressure makes the
gradual letdown process highly effective for noise attenuation.

Fluid Velocity Control

Each stage of the V-LOG* trim is designed with an expansion
in flow area, which is essential for managing fluid velocity that
would otherwise increase as the pressure is reduced across each
stage. The expanding area can compensate for the volumetric
expansion of the gas, reducing any increase in the kinetic energy
as the pressure is reduced.

Trim velocity control is important for maintaining low
aerodynamic noise levels within the valve body and trim. High
velocity trim exit flow will yield high magnitude sound waves,
which lead to valve body vibration in high-pressure letdown
applications.

Exit Flow Jet Spacing

By design, the process fluid is precisely separated into discrete
flow jets upon exiting the V-LOG* trim channels. The proper sizing
and spacing of these channels prevents the exiting flow jets from
reconverging, thus producing lower amplitude sound waves with
higher peak frequencies. These lower sound pressure and higher
frequency waves result in lower acoustical coincidence with
the surrounding system and downstream piping. This reduces
both the overall noise level and vibration effect of the throttling
process.

The V-LOG* Trim’s Labyrinth

Flow Path

Overall System Noise Reduction

As a gas experiences a large reduction in pressure, its volume
expands. This phenomenon will yield a higher downstream
velocity if the piping is configured without considering this
volumetric expansion. Our angle body valve designs feature
expanded outlet areas to accommodate this expansion and
minimize the overall system noise level. (we consider both Outlet
Mach Number and the Outlet Expansion Ratio for system noise
calculation, per the IEC International Noise Prediction Standard
[IEC-60534-8-3]).

GE’s Masoneilan V-LOG* Energy Management Trim for Severe Service Applications | 3

V-LOG* Trim
Features & Benefits

Laser Cut Technology

The V-LOG* trim’s disks are laser cut, resulting in the tight
tolerances and smooth surfaces which are required for throttling
control. Precision trim-part cutting supports throttling area integrity
that is necessary for fine control resolution and accuracy.

Prior to being secured through vacuum-tight brazing, the V-LOG*
trim’s disks are stacked together and aligned using precision
tooling. Each disk is designed with maximum surface area to
promote a secure bond between disks during the brazing process.

Customized Flow Characterization

The laser manufacturing process gives each disk in the V-LOG*
trim the necessary geometry to provide desired control. In addition,
the V-LOG* trim’s stack can be configured with tiered capacities in
each disk to produce specific flow characteristic across the entire
range of travel. For example, the stack design may be configured
with a highly resistant flow path (up to 40 stages) at low lift and
then progressively less resistant flow paths as the valve opens
to its full capacity. Some designs may also combine V-LOG*
trim’s stacked disk technology with drilled-hole or ported-cage
technology.

Laser Cut V-LOG* Trim Disks

These combination trim configurations offer rangeability with
excellent control. This is especially important for applications
requiring the control valve to throttle during plant startup and at
full load production.

Tight Shutoff

The full line of GE’s Masoneilan* V-LOG* trim products achieve
tight shutoff through seating-surface geometry and material
selection. Shutoff performance consistent with ANSI/FCI Class
IV and Class V leakage, as well as MSS-SP-61, is available. Tight
shutoff performance is critical for preventing product loss,
especially in applications that vent to atmosphere or burn off
in a flare stack. Long-lasting tight shutoff is essential in turbine
bypass and compressor surge applications to help protect critical
equipment. To promote overall long-term trim integrity, V-LOG*
trim technology takes full advantage of hardened materials such
as stellite and tungsten carbide.

Characterized V-LOG* Trim & Ported Cage Design

49000 Series with V-LOG* Trim Stack

4 | GE Oil & Gas