In Quebec's industrial sector, both terms typically refer to a control valve. It modulates fluid flow within a flow rate, pressure, or temperature loop. Most importantly, the required function and actuation method must be clearly specified.
INDUSTRIAL PROCESS CONTROL
VAMECA expertly selects and sizes your valves to match your exact operating conditions. Supporting new builds and retrofits across Quebec and Canada.
A part number, a photo, or a few key specifications are all we need to get started.
ARI STEVI Vario · Pneumatic Valve Assembly Example
Body
Provides reliable fluid containment
Actuator
Actuate the stem
Valve Positioner
Adjusts position
ARI-Armaturen · Warren Controls · PS Automation
YOUR REQUIREMENTS
Start with your operational requirements.
Replacement
Replace an existing valve
A nameplate, part number, and a few photos are all we need to accurately identify the valve, its actuation, and its interfaces.
New Project
Select a Valve
Specify your media, flow rates, and operating pressures. Our technical experts will determine the exact parameters required for precise sizing.
Unstable control
Diagnose Before Replacing
Hunting, abnormal noise, or restricted travel: describe the issue and the operating conditions under which it occurs.
APPLICATIONS
Regulate flow, pressure, and temperature.
A control valve modulates fluid flow to regulate flow rate, pressure, or temperature. The application defines the function; the configuration determines how to deliver it.
Flow Rate and Process Modulation
Adjusting flow to fluctuating demand. Minimum and maximum flow rates, fluid properties, and available pressure guide the selection of valve trims.
Pressure and Steam Systems
Reducing downstream pressure or controlling a pressure loop: a modulating control valve and a self-operated pressure reducing valve operate on distinct principles.
Temperature and Heat Transfer
Modulate heat input on a heat exchanger or a water and thermal fluid loop. A two-way valve modulates flow, while a three-way valve mixes or diverts.
Water, Chilled Water, and Hydronics
Regulate a circuit subject to pressure fluctuations. A PICV combines flow modulation and differential pressure control across its regulating segment.
2-Way
Modulated flow through an inline system.
3-Way
Two-stream blending or diverting, depending on the valve model and system configuration.
Self-Operated Control
Depending on the regulator, process pressure or temperature operates self-actuatingly without the need for an external control signal.
SIZING
Sizing a Control Valve: Cv, Kv, and ΔP
Pipe diameter alone is not enough. The Cv or Kv rating defines flow capacity, but proper selection must also ensure stable operation at low loads, manage differential pressure, and deliver reliable shut-off performance.
UNDERSTAND THE VALVE
Inside a control valve.
From actuator to trim, each part has a role in controlling flow.
INSIDE THE TRIM
A guided movement.
The stem transmits actuator movement to the plug. The guiding arrangement keeps the parts aligned throughout the stroke.
DIFFERENTIAL PRESSURE
ΔP = P1 − P2
P1 · upstream pressure P2 · downstream pressure
Compare pressures at the same operating point and with the same pressure reference. Operating ΔP is part of sizing. Shut-off ΔP is checked separately.
Official ARI-Armaturen illustrations · STEVI Vario. These cutaways show one configuration in this range. Trim and actuation vary with the selected model. View manufacturer source ↗
Process Media and Load
Fluid type and phase, minimum, normal, and maximum flow rates, temperature, and units.
Actual Operating Pressures
Upstream and downstream pressures, operating differential pressure, and shut-off conditions. Please specify design extremes.
Body and trim
Required Cv or Kv, flow characteristics, materials, sealing performance, and end connections (NPS/DN, flanged, or threaded).
Actuation and Safety Solutions
Available power supply, thrust or torque output, stroke, control signal, and fail-safe position.
Body Class
Shell pressure-temperature ratings, according to material and class.
Operating ΔP
Differential pressure relative to the process fluid, a critical factor for accurate valve sizing and specification.
Shut-Off ΔP
Differential pressure against which the assembly must shut off. It is also determined by the actuator and internal trim selection.
Hunting or cycling does not necessarily indicate that the valve requires replacement.
Measurement, loop tuning, the actuator, the positioner, or process variations can also account for instability.
PRODUCT LINES & SOLUTIONS
ARI and Warren Valves: Selecting the Optimal Configuration.
VAMECA evaluates and compares ARI-Armaturen and Warren Controls solutions tailored to your facility. Our selection process balances flow capacity, materials, connection types, and actuation, supported by the manufacturer documentation required for seamless engineering validation.
ARI-Armaturen
STEVI
Linear motion globe valves, equipped with electric or pneumatic actuation.
Pro & Vario
Two-way control. Trim, materials, and stem sealing engineered for your specific service conditions.
Smart
Two-way or three-way configurations for mixing and diverting services, as illustrated.
Self-Operated Control
PREDU for pressure reduction. TEMPTROL for self-operated temperature regulation.
Detailed data sheets specify the designs, end connections, and operating limits specific to each model. ASME/ANSI pressure classes, certifications, or CRN numbers are confirmed based on the selected configuration.
VALVES & ACTUATION
Electric or pneumatic actuation.
The process controller transmits a setpoint. The positioner precisely adjusts the position, the actuator delivers the required motion, and the valve accurately modulates the fluid flow.
01 · INSTRUCTIONS
Process Control
Required flow rate, pressure, or operating temperature to be maintained.
02 · POSITION
Positioning
Received signal and actual position compared.
03 · MOTION
Actuator
Thrust or torque, stroke, and operating speed.
04 · FLOW RATE
Valve
Body, seat, and wetted internal components.
Pneumatic
To be evaluated based on the available instrument air supply. Verify thrust/torque output, dynamic response, positioner performance, and spring or accessory fail-safe action.
Electric
To be evaluated based on the available power supply and control signals. Verify the operating speed, modulating duty, and required fail-safe function. Fail-safe return capability is dependent on the specific configuration.
ARI and Warren offer their own dedicated actuated packages, while PS Automation provides reliable electric actuation solutions for both new projects and retrofit applications.
For every assembly, we verify mechanical, electrical, and functional compatibility: interface, torque and thrust, stroke, signal, power supply, and fail-safe position.
REPLACEMENT
Replace an existing control valve.
Identical sizing does not guarantee interchangeability. Interface dimensions and actual process conditions must be validated prior to confirming any replacement.
01
Identify
Body and actuator nameplates, complete part number, and photos of the complete assembly.
02
Measurement
End connections, pressure class, face-to-face dimensions, overall envelope, and actuation interfaces.
03
Return to service
Media, flow rates, operating pressures, temperature, and observed performance.
04
Validate Solution
Compare the proposed configuration against the facility's installation requirements.
FREQUENTLY ASKED QUESTIONS
Your Control Valve Inquiries.
YOUR INQUIRY
Describe your requirements, even if preliminary.
Product selection, valve replacement, or pricing.
Submit your application requirements using our contact form. Our technical specialists will help you determine the critical specifications for optimal product selection.
contact@vameca.ca
Start with your available part number or operating conditions.
Tell us about your project
Describe your application in our contact form. Start with the information you have, even if some details are still unknown.
YOUR REQUESTSelect a control valve for your projectUseful details: fluid, flow rate, upstream/downstream pressure and temperature.
Open the contact form