About KOSO Kent Introl
KOSO Kent Introl Ltd (KKI) is a British severe-service valve manufacturer founded in 1967 in Brighouse, West Yorkshire. Over more than five decades it has built a global reputation for control valves and choke valves that perform reliably in the harshest process conditions – high pressure drops, flashing, cavitation, erosion and high noise. Since 2005 the company has been part of the KOSO Group of Japan (Nihon KOSO Co. Ltd), a worldwide network of around ten companies across nine countries, giving Kent Introl global reach and manufacturing strength while retaining its UK engineering heritage.
Kent Introl pioneered multi-stage low-noise trim technology, the Turbotrol and Rotrol anti-cavitation designs, and the VeCTor labyrinth velocity-control trim. It was the first control-valve company accredited to ISO 9001, has supplied subsea valves since the 1980s qualified to 2,200 metres water depth, and in 2026 was awarded Fit For Nuclear (F4N) status. Its valves are specified by operators including BP, Shell, ExxonMobil, Aramco, Petronas, Petrobras and Equinor.
Kent Introl control, choke and subsea valves are in service across the global energy industry – backed by full aftermarket support.
Why Engineers Choose Kent Introl
Severe Service Expertise
Over 40 years engineering trims that manage cavitation, flashing, erosion and noise where standard valves fail.
Bespoke Engineering
Valves engineered to the exact specification of your application, from material selection to multi-stage trim design.
Subsea Heritage
Series 75 subsea choke and control valves proven in deep-water HPHT service since the 1980s, qualified to 2,200m.
KOSO Group Strength
Backed by a global group spanning nine countries, combining UK engineering with worldwide manufacturing and support.
R&D and AddLab
In-house research, CFD/FEA, noise prediction and advanced additive manufacturing (AddLab) drive continuous innovation.
Full Lifecycle Support
Diagnostics, overhaul, testing, upgrades and asset-life extension keep valves performing for decades.
Choke Valves
Kent Introl choke valves are engineered for the most severe oil & gas service, with a wide choice of materials, anti-erosion trims and sizes. The range pairs the proven Series 73 surface choke with fully bespoke engineered solutions, all backed by fast technical support.
Advanced Surface Choke – Series 73
Severe-service surface choke trusted in oil and gas for 45+ years, with single or multi-stage anti-erosion trims.
Specialist Engineered Solutions
Bespoke chokes built to project needs – bi-directional, in-line, low-shear, high-sand and HP chemical injection.
Globe Control Valves
Kent Introl’s high-performance globe control valve range spans cage-guided, single-seated, double-seated and three-way diverting designs for oil & gas, petrochemical, power and manufacturing. All can be fitted with specialised trims to manage noise, cavitation and erosion.
Cage-Guided – Series 1200 / 7200
Critical-service cage-guided globe valve with high rangeability and severe-service trims; 7200 is the angle version.
Single-Seated – Series 10 / 71
Top-guided single-seated globe valve giving high capacity with tight shut-off and no debris-trapping guide.
Double-Seated – Series 20
High-capacity double-seated globe valve for medium/low-pressure service; HF trim option handles high drops.
Three-Way – Series 30 / 31 / 32
Three-way globe valve for accurate proportional mixing or diverting of flows at high capacity.
Butterfly Control Valves
The high-capacity Introseal butterfly control valve range is a lighter, more compact alternative to globe valves while still protecting against noise and cavitation at high pressure drops – rated to 800 degrees C and 150 bar, with the patented Rotrol anti-cavitation vane for severe service.
Series 63 – Soft Seat
Soft-seat butterfly valve giving Class VI 100% shut-off, for flow control or isolation in demanding service.
Series 64 – Metal Seat
Metal-seat butterfly valve for high-temperature service up to 600 degrees C; leakage Class IV.
Series 65 – Firesafe
Firesafe butterfly valve with a back-up seat that keeps it sealed and operable after a fire.
Series 66 – High Temperature
Seatless butterfly valve for flow control to 800 degrees C and 150 bar where some leakage is acceptable.
Subsea Solutions – Series 75
Kent Introl has supplied subsea valves since 1967. The Series 75 range covers subsea choke and control valves for single or multi-phase production and seafloor processing, engineered for HPHT, deep-water and high shut-in conditions, and backed by intervention tooling and field support.
Subsea Choke Valve – Series 75
HPHT subsea choke for production, injection and gas lift; retrievable designs proven in deep water.
Subsea Control Valve – Series 75
Modulating subsea valve for seafloor processing – seawater injection, boosting, level control and anti-surge.
Intervention Tools (IWOS)
Modular running tool for safe install and retrieval of subsea valves; co-developed with Subsea 7.
Subsea Services & Support
Full-lifecycle support – API 6A Annex J refurbishment, SIT, offshore intervention and hyperbaric testing.
Instruments
To complete every control loop, Kent Introl supplies the supporting valve instruments – positioners, airsets, filter regulators, volume boosters and airlocks – selected to perform reliably in hostile and offshore environments.
Valve Positioner – P3300 / P3300i
Pneumatic and electro-pneumatic positioners that move actuators per the control signal; vibration-tough.
Air Filter / Airset – Series A
Lightweight, durable Series A airsets for control valves and actuators in hostile environments.
316 SS Filter Regulator
Stainless combined filtration and pressure regulation for compressed air in offshore, food and pharma use.
Volume Booster – Series 1000 / 3000
1:1 pneumatic volume boosters that increase actuator stroking speed and flow capacity.
Airlock – PA Series
PA Series airlocks lock diaphragm-chamber pressure when supply air drops below a set value.
Actuators
Kent Introl pneumatic actuators are matched to its control valves for smooth, accurate and responsive operation – from low-friction rolling-diaphragm units to high-thrust piston designs with air-fail action.
Series G – Diaphragm
Spring-opposed diaphragm actuator using a low-friction involute rolling diaphragm.
Series C – Spring-Return Piston
Spring-return piston actuator in a honed cylinder for smooth, low-hysteresis travel.
Series D – Double-Acting Piston
Double-acting piston actuator (Series C with seal plate) for extra air-fail thrust.
Also available from Kent Introl on request: Gas, Liquid and Portable Regulators and Axial Flow Control & Isolation valves. Contact Nhan Viet for specifications and selection support.
Severe Service Solutions
“Severe service” arises when pressure drops, flashing, multi-phase flow or contamination create erosion, cavitation, vibration and noise that destroy standard valves. Kent Introl has spent over 40 years engineering trim technologies that bring these conditions under control.
VeCTor Velocity Control Trims
Labyrinth trim that limits damaging velocities for high-temperature, high pressure-drop service.
Multi-Stage Trim Technology
Stages high pressure drops to avoid cavitation, with up to 30 stages of pressure let-down.
Erosive Application Solutions
Tailored valve and material combinations, such as tungsten carbide, to resist erosion in onerous duty.
Dynamic Response Testing
Fast, stable valve and actuator assemblies for applications needing high speed and accuracy.
Noise Reduction
Low-noise solutions that stage pressure drops or divide flows to meet site noise limits.
Real-World Applications
Kent Introl valves solve specific, recurring process challenges across the energy industry. These are some of the applications where their severe-service designs are most often specified.
Anti-Surge – Compressor Recycle
Stable, fast flow control that stops compressors moving toward surge and prevents reverse flows.
Pipeline Surge Relief Control
Controls large surges and reverse flows on long pipelines to prevent damaging pressure spikes.
Pump Minimum Flow Recirculation
Multi-stage trim that stages pressure drops to eliminate cavitation in pump recirculation lines.
Fire Water Deluge System
Severe-service valves for fire water deluge systems that resist cavitation in harsh offshore service.
Separator Level Control
Erosion-resistant valves and trims for separator level control in the oil production process.
Aftermarket Services
Kent Introl’s dedicated aftermarket facility supports valves of any make throughout their lifecycle – from diagnostics and overhaul to upgrades and asset-life extension – mobilised on-site or globally as required.
Valve Diagnostics
Data-driven predictive maintenance that measures in-service valve performance to plan work.
Overhaul & Repairs
Full strip-down, inspection, reassembly and testing of valves on-site or at the Brighouse facility.
Servicing & Maintenance
Planned maintenance and refurbishment from a dedicated aftermarket facility, mobilised globally.
Testing
Gas, tensile, PR2, flow, emissions and fire testing in four in-house bays to international standards.
Upgrades & Spares
Upgrades, retrofits and genuine spares to keep valves fit-for-purpose as conditions change.
Asset Life Extension
Strategies that safely extend the service life of ageing oil and gas installations and equipment.
Training
Tailored hands-on courses, from basic valve construction to advanced sizing and selection.
Industries We Serve in Vietnam
Through Nhan Viet ICS JSC, Kent Introl valves support Vietnam’s energy and process industries with severe-service performance and full local technical support.
Global Certifications & Standards
KOSO Kent Introl manufactures to internationally recognised quality, safety and environmental standards, supporting full compliance for Vietnamese projects and audits.
ISO 29001:2020
ISO 14001
ISO 45001
PED 2014/68/EU
ATEX
API Spec Q1
API 6A Monogram
API 17D Monogram
TR CU
SEQual
Fit For Nuclear (F4N)
Chinese TSG
Why Partner with Nhan Viet ICS JSC
Local Technical Expertise
Flow-control specialists who help you size, select and specify the right Kent Introl valve for your service conditions.
Faster Response in Vietnam
A local point of contact for quotations, documentation and project coordination – in your time zone and language.
Project & EPC Support
Support for tenders, datasheets, compliance and delivery coordination on EPC and end-user projects.
Genuine Parts & Aftercare
Authentic Kent Introl spares and access to overhaul, upgrade and asset-life-extension services.
Flow Control Portfolio
Kent Introl complements our wider portfolio of valves, instrumentation and flow-control brands for a complete solution.
Trusted & Authorized
As an authorized channel, we ensure you receive genuine, fully warranted Kent Introl products and documentation.
Lead Times, Documentation & After-Sales
Sizing & Selection
Severe-service valve selection depends on accurate process data – pressure drop, flow, fluid, temperature and noise limits. Share your datasheet or process conditions and we will work with Kent Introl’s engineering team to recommend the right body, trim and actuator combination.
Documentation & Compliance
We supply full material certificates, test reports, NACE/NORSOK compliance and dimensional drawings to meet EPC and operator requirements, including API 6A and ATEX/PED documentation where applicable.
After-Sales & Spares
Beyond supply, we connect you to Kent Introl’s aftermarket capability – diagnostics, overhaul, testing, upgrades and asset-life extension – to maximise the return on your installed valves over their full lifecycle.
Frequently Asked Questions
Is Nhan Viet an authorized distributor of KOSO Kent Introl in Vietnam?
Nhan Viet ICS JSC supplies and supports the full KOSO Kent Introl range in Vietnam, including sizing, selection, documentation and aftermarket coordination. Contact us to confirm availability and commercial terms for your project.
What is a “severe service” valve?
Severe service refers to conditions where high pressure drops, flashing, multi-phase flow or contamination cause erosion, cavitation, vibration and excessive noise. Kent Introl specialises in multi-stage and velocity-control trims engineered specifically to manage these conditions.
What is the difference between a control valve and a choke valve?
Control valves modulate flow within a process loop, while choke valves are designed primarily to manage and reduce high wellhead pressures in oil & gas production. Kent Introl manufactures both, including the Series 73 surface choke and Series 75 subsea choke.
Does Kent Introl supply subsea valves?
Yes. The Series 75 range includes subsea choke and control valves for production, injection, gas lift and seafloor processing, with retrievable designs proven in deep-water HPHT service and qualified to 2,200 metres water depth.
Which globe control valve type should I choose?
Cage-guided (Series 1200/7200) suits high-rangeability critical service; single-seated (Series 10/71) offers high capacity and tight shut-off; double-seated (Series 20) handles high capacity at lower pressures; three-way (Series 30/31/32) mixes or diverts flows. We will help you select based on your process data.
Can Kent Introl service valves from other manufacturers?
Yes. Kent Introl’s aftermarket facility provides diagnostics, overhaul, testing, upgrades and asset-life extension for valves of any make, mobilised on-site or at their UK facility.
What certifications do Kent Introl valves carry?
Kent Introl is accredited to ISO 9001, ISO 29001, ISO 14001 and ISO 45001, holds API Spec Q1 with API 6A and API 17D monogram licenses, and provides PED and ATEX conformity. It also holds Fit For Nuclear (F4N) status.
What information do you need to provide a quotation?
Ideally a valve datasheet or the process conditions – fluid, flow rate, inlet/outlet pressure, temperature, pipe size and any noise or material requirements. With that we can recommend the correct valve, trim and actuator and prepare a quote.
Who owns Kent Introl?
KOSO Kent Introl has been part of the KOSO Group of Japan (Nihon KOSO Co. Ltd) since 2005, combining British severe-service engineering with the scale and global reach of a worldwide valve group.
Request a Quote or Technical Consultation
Talk to Nhan Viet ICS JSC about KOSO Kent Introl control valves, choke valves and severe-service solutions for your project in Vietnam.
Nhan Viet ICS JSC – Flow Control Solutions
Website: nhanvietgroup.vn