BM TECH — NBS Europe — is the sole Authorized Representative of NBS Corporation in Europe, providing supply, installation and full lifecycle service for NBS UNIFLOW and UNICON valves in PSA oxygen, nitrogen, CO₂ and CO production plants across Europe, the Middle East and North Africa.
PSA plants do not use generic industrial valves. The switching valves at the heart of a Pressure Swing Adsorption cycle — opening and closing thousands of times per day, handling rapid pressure differentials, operating in continuous automated service with no tolerance for unplanned failure — require valves engineered specifically for this duty.
NBS Corporation developed the UNIFLOW and UNICON valve series to meet exactly these requirements. For decades, NBS switching valves have been the valve of choice for PSA plant builders and operators worldwide — specified by Air Liquide, Air Products and Chemicals, Linde, Air Water, Daesung Industrial and Sumitomo Seika Chemicals in oxygen, nitrogen, CO₂ and CO production plants across Japan, Korea, China, the United States and Europe.
As NBS Europe, BM TECH brings that proven technology — and the full service capability to support it — directly to European PSA plant operators.
Pressure Swing Adsorption is a continuous gas separation process in which a feed gas mixture — typically air — is passed through one or more adsorption towers packed with a selective adsorbent material. The adsorbent retains the unwanted components (nitrogen in oxygen PSA; oxygen and CO₂ in nitrogen PSA) while the product gas passes through. When the adsorbent approaches saturation, the tower is depressurised, the adsorbed components are desorbed and expelled, and the adsorbent is regenerated — ready for the next adsorption cycle.
In a typical two-tower PSA system, this cycle repeats continuously — with the two towers alternating between adsorption and regeneration phases. A multi-tower system distributes the cycle across three, four or more towers to smooth product flow and increase overall efficiency.
The valve is the mechanism that makes the cycle work. At each phase transition — pressurisation, adsorption, depressurisation, purge, equalisation — specific valves open and close in a precisely timed sequence. The speed, reliability and repeatability of that switching sequence directly determine:
In a PSA plant producing medical or industrial oxygen, nitrogen for food packaging or CO₂ for beverage carbonation — valve performance is not a maintenance metric. It is a product quality and production continuity metric.
The NBS UNIFLOW and UNICON valve series are designed from the ground up for the specific demands of PSA switching service:
High-cycle design life PSA switching valves complete between 500,000 and several million open-close cycles per year depending on cycle time. NBS UNIFLOW/UNICON valves are engineered and tested for multi-million cycle service life — with seat materials, disc geometry and actuator specifications matched to sustained high-cycle duty.
Fast, consistent switching response PSA cycle efficiency depends on precise valve timing. NBS valves deliver fast, consistent opening and closing response — cycle after cycle — ensuring that adsorption and regeneration phases begin and end at the correct moments.
Tight shutoff throughout service life Seat leakage in a PSA switching valve allows gas to bypass the adsorption tower during the wrong phase of the cycle — directly degrading product purity and recovery. NBS valve seat designs maintain tight shutoff across the full rated cycle life, not just at the beginning of service.
Robust actuator design PSA switching valves operate under continuous automated control. NBS pneumatic actuators are designed for the high duty cycle of PSA service — with cylinder construction, seal materials and spring specifications selected for sustained continuous operation.
Full media compatibility NBS UNIFLOW/UNICON valves are available in configurations compatible with oxygen service (including oxygen-clean assembly procedures), nitrogen, CO₂, CO and other PSA product and feed gases — with body and internal materials selected for full compatibility with each medium.
Based on NBS Corporation’s documented reference installations, UNIFLOW/UNICON valves serve the following duties in PSA plants:
Adsorption tower switching valves The primary switching valves at the inlet and outlet of each adsorption tower — the highest duty cycle valves in the plant. These valves control the pressurisation, adsorption, depressurisation and purge phases of each tower. Valve reliability at this duty point determines overall plant availability.
Vacuum pump bypass valves (VPSA) In Vacuum Pressure Swing Adsorption systems, vacuum pump bypass valves control the depressurisation phase by routing gas around the vacuum pump during specific cycle phases. These valves handle the combined demands of high cycle frequency and the vacuum pressure conditions specific to VPSA operation.
Gas product line valves Isolation and control valves on the product gas delivery line — maintaining product purity integrity from the adsorption tower outlet to the downstream process or storage system.
O₂, N₂, CO₂ and CO manufacturing equipment NBS valves serve across the full range of PSA gas production applications — oxygen for medical, industrial and combustion enhancement applications; nitrogen for food packaging, electronics manufacturing and inerting; CO₂ for beverage carbonation, food processing and industrial use; CO for chemical synthesis.
NBS UNIFLOW/UNICON valves have been specified and installed by the world’s leading industrial gas producers and PSA plant builders:
Air Liquide — France and global operations Air Products and Chemicals — USA, Korea, China and global operations Air Water Inc. — Japan and Asia-Pacific Daesung Industrial — Korea Linde — USA and global operations Sumitomo Seika Chemicals Co., Ltd. — Japan
These are not pilot installations. These are production-scale PSA plants operated by companies whose business depends on continuous, reliable gas production. Their repeated specification of NBS valves across multiple facilities and multiple decades of operation is the most reliable indicator of valve performance available.
As NBS Europe, BM TECH provides European PSA plant operators with direct access to the same valve technology — and the service capability to support it throughout its operational life.
Supply and Specification
BM TECH supplies NBS UNIFLOW/UNICON valves for new PSA plant installations and for replacement of existing switching valves — whether NBS original equipment or other manufacturer’s valves reaching end of service life.
Our technical team supports the specification process — reviewing PSA cycle parameters, switching frequency, operating pressures, product gas type and purity requirements — and recommending the correct NBS valve configuration, actuator specification and control interface for each application.
Valve Condition Assessment
For operating PSA plants, BM TECH provides valve condition assessment services — evaluating the condition of installed switching valves against cycle count, observed performance data and inspection findings to determine remaining service life and plan replacement before failure occurs.
This assessment is particularly valuable for plants where the original valve installation date is known but maintenance records are incomplete, or where product purity or recovery performance has declined without an identified cause — seat leakage in one or more switching valves being a common root cause of gradual performance degradation.
Planned Maintenance and Overhaul
PSA switching valve maintenance should be planned around cycle count — not calendar time. A valve completing 2,000 cycles per day reaches one million cycles in approximately 500 days. A valve completing 500 cycles per day reaches the same milestone in four years. Calendar-based maintenance intervals that do not account for actual cycle count will either over-maintain low-duty valves or under-maintain high-duty valves.
BM TECH establishes maintenance intervals based on actual cycle count data — where available from plant control systems — and on valve condition assessment findings. Planned maintenance covers:
Rapid Response for Unplanned Failures
PSA plant operation is continuous. A switching valve failure that stops the cycle cannot wait for a standard maintenance lead time. BM TECH maintains stock of critical NBS UNIFLOW/UNICON spare parts and provides rapid response service — on-site intervention and expedited parts supply — to restore plant operation with minimum downtime.
Valve Replacement Programme
For PSA plants approaching the end of the designed service life of their original switching valve population, BM TECH develops structured replacement programmes — scheduling valve replacement during planned maintenance windows to prevent the cluster of unplanned failures that typically occurs when a large population of same-age valves approaches end of life simultaneously.
Direct NBS access As the sole Authorized Representative of NBS Corporation in Europe — and since June 2025, NBS Europe — BM TECH provides direct access to original NBS valves, spare parts and technical support. There is no intermediary between the European customer and NBS Corporation’s engineering resources.
PSA-specific expertise BM TECH’s service team has direct experience in PSA and VPSA valve service — understanding the cycle parameters, switching requirements and failure modes specific to this application. Generic valve service experience is not sufficient for PSA switching valve maintenance.
Original spare parts NBS spare parts — not aftermarket alternatives — are held in stock for rapid supply. Original parts maintain the cycle life performance of NBS valves; aftermarket substitutes typically do not.
European service coverage BM TECH provides on-site service across Europe, the Middle East and North Africa — covering the geographic footprint of European industrial gas producers and PSA plant operators.
Technical documentation Full NBS technical documentation — valve specifications, maintenance procedures, spare parts lists — is available to BM TECH customers. This documentation is not publicly available and is not accessible through non-authorised service providers.
For PSA plant operators managing their switching valve population, BM TECH recommends monitoring the following performance indicators as early indicators of valve condition deterioration:
Product purity trend — gradual decline in product purity without a change in feed gas composition or adsorbent condition indicates increasing seat leakage in one or more switching valves.
Product recovery rate — declining recovery at constant feed flow and cycle parameters indicates valve timing errors or seat leakage causing gas to bypass the adsorption phase.
Cycle completion rate — valves that fail to complete their switching movement within the programmed time window generate cycle errors in the plant control system. Increasing cycle error frequency indicates actuator degradation.
Actuator air consumption — increasing compressed air consumption by pneumatic actuators indicates seal wear, allowing air to bypass the piston without producing valve movement.
Tracking these metrics — and correlating them with valve cycle count — allows maintenance intervention to be planned before performance degradation affects product quality or plant availability.
Whether you are specifying NBS valves for a new PSA plant, planning maintenance of an existing switching valve population, or dealing with an urgent valve failure — BM TECH is ready to respond.
Contact NBS Europe:
Request Service Support Request a Spare Parts Quote Schedule a Valve Assessment Download NBS UNIFLOW/UNICON Technical Data
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PSA oxygen and nitrogen plant switching valve service
VPSA vacuum switching valve and bypass valve service
Depending on cycle time, PSA switching valves complete between 500,000 and several million cycles per year. NBS UNIFLOW/UNICON valves are engineered for multi-million cycle service life — contact BM TECH with your cycle parameters for a specific service life assessment.
Air Liquide, Air Products and Chemicals, Linde, Air Water, Daesung Industrial and Sumitomo Seika Chemicals have all specified NBS UNIFLOW/UNICON valves in their PSA oxygen and nitrogen plants. Full reference details are available from BM TECH on request.
Gradual product purity decline without changes in feed air composition or adsorbent condition is the primary indicator of switching valve seat leakage. BM TECH can review your plant performance trends and advise on whether valve condition assessment is indicated.
Yes — subject to dimensional compatibility assessment. Contact BM TECH with existing valve dimensions and process parameters for a replacement evaluation.
BM TECH provides on-site PSA valve service across Europe, the Middle East and North Africa from our Warsaw base. Contact us to discuss service coverage for your specific location.