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 on chemical tankers, product tankers and specialized cargo vessels operating in European and international waters.
Of all marine vessel types, the chemical tanker places the broadest and most demanding requirements on valve engineering. A crude oil tanker carries one product. An LNG tanker carries one cryogenic gas. A chemical tanker may carry thirty or more different cargo parcels simultaneously — each in a dedicated stainless steel tank, each with its own chemical compatibility requirements, each requiring complete isolation from every other cargo on board.
Methanol. Styrene. Sulphuric acid. Vegetable oils. Caustic soda. Ethylene oxide. Molasses. Each cargo requires valves that are compatible with its specific chemical properties — and each cargo tank must be completely isolated from adjacent tanks carrying incompatible products. A valve that allows cross-contamination between cargo parcels does not simply cause a quality problem. It may cause a chemical reaction between incompatible products in a confined shipboard environment — with consequences that no ship operator, cargo owner or classification society is willing to contemplate.
Beyond cargo compatibility, chemical tanker valves operate in the marine environment — continuous salt air exposure, vessel motion, vibration, the thermal cycling of tropical and arctic operations — and must meet the requirements of IMO regulations, IBC Code provisions and the rules of marine classification societies whose surveyors inspect these vessels at regular intervals throughout their operational life.
NBS Corporation developed the UNIFLOW and UNICON valve series with the specific requirements of chemical tanker service as a foundational design parameter. Validated across chemical tankers built by Fukuoka Shipbuilding, Higaki Ship Building, Kitanihon Shipbuilding, Minaminippon Shipbuilding, Shin Kurushima Dockyard and Usuki Shipyard — six of Japan’s leading chemical tanker builders — NBS UNIFLOW/UNICON valves carry a track record in this service that no European valve manufacturer can match.
As NBS Europe, BM TECH brings that proven chemical tanker valve technology — and the full European service infrastructure to support it — to ship managers, technical superintendents and drydock operators managing chemical tanker fleets in European and international waters.
The International Bulk Chemical Code — administered by the International Maritime Organization — is the primary regulatory framework governing the design, construction and operation of ships carrying noxious liquid substances in bulk. For valve engineers and ship managers, the IBC Code defines requirements that cannot be compromised:
Cargo containment system integrity The IBC Code requires that the cargo containment system — including all valves in the cargo flow path — maintains integrity against the cargoes being carried. This means that valve body materials, seat materials, seal materials and coatings must be verified as compatible with each cargo listed in the vessel’s Certificate of Fitness.
Cargo isolation requirements Tanks carrying incompatible cargoes must be isolated by double valve arrangements or by other means that prevent cross-contamination even in the event of a single valve failure. The reliability and tight shutoff performance of cargo isolation valves is therefore a regulatory requirement, not merely a quality consideration.
Vapour control and venting The IBC Code defines requirements for cargo vapour control — limiting vapour release to atmosphere for toxic and environmentally harmful cargoes, and controlling vapour accumulation in enclosed spaces. Vent line valves and vapour control system valves must function reliably to meet these requirements.
Pump room safety The pump room — where cargo pumps, stripping systems and associated valves are located — is a potentially hazardous enclosed space. Valve reliability in the pump room directly affects personnel safety during cargo operations.
Emergency systems Remote-operated cargo isolation valves must close automatically on activation of the ship’s emergency systems — protecting cargo containment integrity in fire, flooding or collision scenarios.
BM TECH supplies NBS UNIFLOW/UNICON valves with the IBC Code compliance documentation required for vessel Certificate of Fitness applications and classification society survey — and advises ship managers on valve specifications that meet IBC Code requirements for specific cargo lists.
Based on NBS Corporation’s reference installations across six Japanese chemical tanker builders, UNIFLOW/UNICON valves serve the following duties on chemical tankers:
Cargo Line — Manifold Valves The cargo manifold is the connection point between the vessel and the shore terminal — handling the full cargo flow rate during loading and discharging operations. Manifold valves must provide reliable, rapid shutoff for emergency disconnection, must handle the full range of chemical cargoes listed in the vessel’s Certificate of Fitness, and must resist the corrosive effects of salt air and chemical vapour in the manifold area. Stainless steel body and trim construction is standard for chemical tanker manifold valves, with seat and seal materials selected for compatibility with the vessel’s cargo list.
Cargo Line — Diffusing Valves Diffusing valves control the distribution of incoming cargo from the manifold to individual cargo tanks during loading — directing cargo flow to the correct tank in the correct sequence and preventing cross-contamination between cargo parcels. Diffusing valve reliability is critical during multi-parcel loading operations where multiple tanks are being loaded simultaneously with different cargoes.
Cargo Line — Discharging Valves Cargo pump discharge valves control the flow of cargo from pump discharge to the manifold during discharging operations. These valves handle the discharge pressure of the cargo pumps — typically 5 to 10 bar above cargo tank pressure — and must provide tight shutoff to prevent cargo siphoning when pumps are stopped.
Cargo Line — Drop-Line Valves Drop-line valves provide an alternative cargo loading path — allowing cargo to be loaded by gravity flow directly into the tank bottom without passing through the pump room, reducing the risk of cargo contamination from pump room surfaces and simplifying loading operations for certain cargo types.
Cargo Line — Common Line Valves Common line valves connect individual cargo tank lines to shared manifold headers — allowing flexible routing of cargo flow between tanks and manifold connections. The isolation reliability of common line valves is critical for preventing cross-contamination between cargo parcels sharing a common header.
Vent Line — Common Venting Valves Common venting valves connect individual cargo tank vent lines to a shared vent header — allowing controlled venting of cargo vapour from multiple tanks through a single vent mast or vapour collection system. These valves must provide tight shutoff to prevent vapour migration between tanks carrying incompatible cargoes through the shared vent system.
Vent Line — Venting for Cargo Tank Line Individual cargo tank vent valves control vapour release from each tank independently — required for cargoes where vapour control is mandatory under the IBC Code or where cargo vapour recovery systems are installed.
Tank Cleaning — Pump Room Valves Tank cleaning water supply and discharge valves in the pump room handle wash water, tank cleaning chemicals and residual cargo during the cleaning cycle between cargo parcels. These valves must handle not only the cleaning media but also the residual traces of the previous cargo — requiring broad chemical compatibility and robust resistance to the mechanical action of high-pressure cleaning systems.
Tank Cleaning — On-Deck Valves On-deck tank cleaning valves provide connections for portable tank cleaning machines and control wash water distribution during tank cleaning operations. These valves are exposed to the full marine environment — salt air, spray, UV — in addition to the cleaning media they handle.
ODM Waste Collection / Discharge Line — Pump Room Valves Oil and chemical waste collection valves handle the collection, temporary storage and discharge of cargo residues, tank washing water and other shipboard liquid waste streams in compliance with MARPOL Annex II requirements. These valves must handle a broad range of chemical residues with varying corrosive and toxic properties.
Outboard Valve — Pump Room The outboard valve — the overboard discharge valve for ballast, tank cleaning water and other liquid discharges — is one of the most critical valves on the vessel from a regulatory compliance perspective. MARPOL Annex II prohibits the discharge of certain noxious liquid substances to sea, and the outboard valve is the final barrier between the ship’s liquid waste systems and the marine environment. Outboard valve integrity and reliable remote closure are mandatory requirements.
The fundamental engineering challenge of chemical tanker valve specification is chemical compatibility — ensuring that every component of every valve in the cargo flow path is compatible with every cargo the vessel may carry.
This is not a simple material selection exercise. A vessel’s cargo list may include:
Organic chemicals — alcohols (methanol, ethanol, propanol), esters, ketones, aromatics (benzene, toluene, xylene), chlorinated solvents — each with different solvent aggressiveness toward elastomeric seal materials and surface coatings.
Inorganic acids and alkalis — sulphuric acid, phosphoric acid, hydrochloric acid, caustic soda, ammonia solutions — requiring corrosion-resistant alloy body materials and chemically resistant seal compounds.
Vegetable and animal oils — palm oil, soya oil, fish oil, tallow — requiring food-grade compatible materials and thorough cleanability between cargoes.
Specialty chemicals — styrene (which polymerises if contaminated), ethylene oxide (toxic and reactive), acrylates (reactive), isocyanates (toxic) — requiring the highest standards of valve cleanliness and isolation integrity.
Molasses and food-grade products — requiring surfaces that can be thoroughly cleaned and that do not contribute extractable contaminants to the cargo.
For each cargo, BM TECH verifies the compatibility of NBS UNIFLOW/UNICON valve materials — body, trim, seat and seal — against the chemical properties of the cargo at the operating temperature and concentration. Where standard configurations are not compatible, BM TECH specifies alternative seat and seal materials, body coatings or special alloy trim configurations that provide the required compatibility.
This compatibility verification is documented — providing the technical basis for IBC Code compliance claims and classification society review.
Chemical compatibility is the primary specification challenge, but chemical tanker valves must also withstand the marine environment throughout a vessel service life that may extend to 25 years between major rebuilds:
Salt air and spray corrosion External valve surfaces — particularly on-deck and manifold area valves — are continuously exposed to salt-laden marine atmosphere. External corrosion protection through material selection, coating systems and regular maintenance inspection is essential for preserving valve operability over the vessel’s service life.
Vibration and shock loading Vessel motion in heavy weather produces vibration and shock loads on all shipboard equipment. Valve actuators, position indicators and control connections must be designed and installed to withstand these loads without loosening, fatigue cracking or loss of function.
Temperature cycling Chemical tankers operate in tropical and arctic conditions — ambient temperatures ranging from −20°C to +45°C. Cargo temperatures add further variation — heated cargoes at up to +80°C, refrigerated cargoes at −10°C and below. Valve materials and seal compounds must maintain their properties across this full temperature range.
Biofouling in submerged applications Outboard valves and hull penetration fittings are subject to marine biofouling — the accumulation of marine organisms on submerged surfaces. Biofouling can impair valve operation by increasing operating torque and can accelerate corrosion under the biofilm layer. Antifouling provisions and regular inspection during drydock are required for submerged valves.
NBS Corporation UNIFLOW/UNICON valves have been installed in chemical tankers built by:
Fukuoka Shipbuilding Co., Ltd. Higaki Ship Building Co., Ltd. Kitanihon Shipbuilding Co., Ltd. Minaminippon Shipbuilding Co., Ltd. Shin Kurushima Dockyard Co., Ltd. Usuki Shipyard Co., Ltd.
Six of Japan’s leading chemical tanker constructors — covering the full range of chemical tanker types from small coastal product tankers to large ocean-going IMO Type II and Type III chemical carriers. Vessels built by these yards are operating in European waters today, managed by European ship management companies, calling at European chemical terminals and undergoing drydock maintenance in European shipyards.
BM TECH provides the European valve service infrastructure that these vessels need — with direct access to original NBS spare parts, classification society documentation support and service engineers experienced in chemical tanker valve maintenance.
Drydock Valve Service Programme
Chemical tanker drydock maintenance is the primary opportunity for comprehensive cargo valve inspection, overhaul and replacement. A typical chemical tanker drydock involves:
BM TECH coordinates drydock valve service programmes — providing advance parts supply, pre-mobilisation of service engineers to the drydock location and full documentation packages for classification society survey.
Running Maintenance — Port and Voyage Maintenance
Between drydock periods, valve maintenance is carried out during port calls and, for accessible valves, during voyage. BM TECH provides running maintenance support across European ports — emergency valve repair, actuator replacement and seat maintenance for accessible cargo and vent valves.
Cargo Compatibility Assessment
When a vessel’s cargo list changes — adding new cargoes or extending to different chemical families — a compatibility assessment of the installed valve population is required to verify that existing valve materials remain suitable for the new cargoes. BM TECH provides cargo compatibility assessments for NBS UNIFLOW/UNICON valves — reviewing body material, seat and seal compatibility against the proposed cargo list and identifying any valves requiring seat or seal replacement before the new cargoes are carried.
Emergency Response
Cargo valve failure during a loading or discharging operation — whether through actuator failure, seat leakage or mechanical damage — can stop cargo operations and detain the vessel at berth. BM TECH provides emergency response service at European ports — rapid mobilisation of service engineers and expedited spare parts supply to restore cargo valve operability with minimum vessel delay.
Certificate of Fitness Support
NBS UNIFLOW/UNICON valve material documentation — body material certificates, seat and seal compatibility data, pressure test certificates — supports vessel Certificate of Fitness applications and renewals. BM TECH maintains this documentation for all NBS valves supplied and provides it to ship managers on request.
Cargo isolation valve seat leakage — periodic leak testing of cargo tank isolation valves verifies that tight shutoff is maintained between adjacent cargo parcels. Increasing seat leakage indicates seat wear or damage requiring maintenance before the next cargo loading.
Remote operation response time — remotely operated cargo and emergency valves must respond within the time specified by the vessel’s safety management system. Periodic response time testing verifies that actuator performance has not degraded.
Vent valve seat condition — vent line valves that leak allow vapour migration between cargo tanks — a particular concern where incompatible cargoes are carried in adjacent tanks sharing a common vent header.
Outboard valve integrity — the outboard valve is subject to periodic testing under class survey requirements. Between surveys, external condition inspection during port calls identifies corrosion or mechanical damage requiring repair.
Actuator air supply integrity — pneumatic actuator systems require clean, dry instrument air at the specified supply pressure. Moisture ingress into actuator air systems — common in the marine environment — causes actuator seal degradation and control system corrosion.
Pump room valve operability — pump room valves that are infrequently operated can seize through corrosion or cargo residue buildup. Periodic exercising of all pump room valves — opening and closing through full travel — verifies operability and identifies valves requiring maintenance before they are needed in service.
Whether you are planning a drydock valve maintenance programme, assessing cargo compatibility for a new cargo list, dealing with a valve failure during cargo operations, or specifying NBS valves for a new chemical tanker build — BM TECH is ready to assist.
Contact NBS Europe:
Request Service Support Request a Spare Parts Quote Schedule a Valve Assessment Download NBS UNIFLOW/UNICON Technical Data
ASU cryogenic valve service — air separation units
LNG/LPG tanker and terminal cryogenic valve service
Chemical tanker IBC Code cargo valve service
PSA oxygen and nitrogen plant switching valve service
VPSA vacuum switching valve and bypass valve service
Contact BM TECH at biuro@bmtech.eu with your vessel’s current Certificate of Fitness cargo list, the NBS valve model numbers installed on board (from vessel maintenance records or the original shipyard documentation), and any specific cargoes of concern. We will provide a documented compatibility assessment within five to seven business days for standard cargo lists.
NBS UNIFLOW/UNICON valves were installed in chemical tankers built by Fukuoka Shipbuilding, Higaki Ship Building, Kitanihon Shipbuilding, Minaminippon Shipbuilding, Shin Kurushima Dockyard and Usuki Shipyard. If your vessel was built by one of these yards, it is likely to have NBS valves in the cargo system. BM TECH can confirm valve identification from shipyard documentation if required.
Yes. BM TECH provides port service for chemical tanker valve maintenance — mobilising service engineers to the vessel location for actuator repair, seat maintenance on accessible valves and remote operation testing. Contact us with the vessel’s port call schedule and maintenance scope to arrange service attendance.
Based on our service experience, the most common causes of cargo valve failure in European service are actuator seal degradation — accelerated by moisture ingress into pneumatic systems in the marine environment — and seat leakage resulting from accumulated cargo residue deposits or chemical attack on seat materials from cargoes at the limits of material compatibility. Both failure modes are preventable through correct maintenance intervals and cargo compatibility management.
BM TECH provides valve maintenance records and certification documents that support vessel ISM Code records and can be presented during Port State Control inspections. We recommend that ship managers maintain a complete valve maintenance record file aboard the vessel, updated after each maintenance intervention. BM TECH provides documentation in the format required by the vessel’s SMS documentation system.