FAQ

Qingdao Exsafe Valve Co., Ltd. is a marine valve manufacturer with valve manufacturing experience dating back to 1995. EXSAFE specializes in high-speed breathable P/V valves and also provides regulating valves, air caps, marine valves, strainers, strainers, pipe accessories as well as manufacturing, forging and machining services.

The core advantage of EXSAFE is the high-speed breathable P/V valve. The product is designed with stable operation as the goal, adopts metal-to-metal sealing, and verifies actual leakage performance through tests and approval documents of specific models. It also has the characteristics of non-oscillation, no need to replace magnets, and low life-cycle costs.

The core product is high-speed breathable P/V valves, while providing explosion-proof electric P/V valves, regulating valves, air caps, general marine valves, filters, pipeline accessories and customized processing services.

Mainly for ship owners, ship management companies, shipyards, ship repair yards, ship service companies, valve dealers, system integrators and dual-fuel transformation contractors.

High-speed breathable P/V valves are mainly used in oil tankers, chemical tankers and product tankers; air caps, marine valves and filters can also be used in bulk carriers, container ships, offshore engineering ships and other ship types.

Beyond safety. For P/V valves, the technical proposition is: stability comes from fluid power, not magnetism.

EXSAFE is factory-based and has product design, manufacturing coordination, testing, technical support and customization capabilities, so it can support both standard supply and project engineering needs.

The existing verifiable documents on the website include CCS, DNV and BV type approval. The specific model, diameter, material and pressure range must be subject to the latest complete certificate.

P/V valve belongs to the safety-critical equipment of cargo hold ventilation system. Type approval helps shipowners and shipyards verify that products meet applicable safety, fire resistance and performance requirements.

Common reference documents include IMO MSC.1/Circ.677/Rev.1, ISO 15364:2021 and ISO 16852:2016. Project requirements may also depend on flag state, classification society, ship type, cargo and shipyard specifications.

ISO 15364:2021 covers pressure/vacuum valves for cargo holds and related ship applications, including performance, testing and safety-related requirements. When used in contracts or projects, formal standards and classification society approval documents should prevail.

This document provides guidance related to ventilation systems and devices to prevent flames from entering cargo holds. It is an important reference document for the ventilation safety of oil tanker cargo holds.

The design goal of EXSAFE is to achieve non-oscillating, non-hammering operation. A wide body hydrodynamic structure is used to reduce sensitivity to pressure fluctuations and maintain stable opening and closing.

For the user, this means that the valve should not repeatedly flutter, bump or hammer during normal operation, thereby reducing noise, vibration, valve seat damage, leakage risk and maintenance costs.

In practical discussions, 0.5 Hz is often used as a reference threshold to determine whether repeated opening and closing movements are unacceptable. EXSAFE's test concept is to achieve stable operation and avoid repeated contact between the valve seat and the valve disc during the test. Specific test methods and classification society interpretations shall be subject to applicable requirements.

Yes. EXSAFE can provide relevant certificates, inspection records and technical documents based on the order scope, product model and classification society or customer requirements.

Yes. EXSAFE can support drawings, certificates, technical data sheets, installation instructions and other documents required by shipyards or ship management companies.

Not necessarily. Certificate scope depends on model, material, dimensions and approval conditions. The specific scope of approval for each project should be confirmed by EXSAFE before quotation or technical submission.

High-speed ventilation P/V valve is used in cargo hold ventilation system. When the pressure in the cabin exceeds the set value, the steam is discharged at high speed, and when the vacuum reaches the set value, air is allowed to enter, thereby protecting the cargo hold.

P/V is the abbreviation of Pressure/Vacuum, namely pressure/vacuum. Valves are used to limit excessive positive and negative pressure in cargo tanks.

Usually according to ship design, classification society requirements and shipyard drawings, it is installed at the cargo hold ventilation pipeline or tank ventilation outlet.

Adopting a wide body gravity structure optimized by hydrodynamics, the opening and reseating stability is improved through the flow channel, effective stress area and force balance design, and does not rely on magnet control.

This means that the valve mainly achieves stable operation through structural geometry, flow area, pressure and force balance, reducing maintenance variables caused by magnet aging, inspection and periodic replacement.

Magnets may bring about life cycle problems such as magnetic changes, need for replacement, and maintenance uncertainty. EXSAFE uses a non-magnetic route to reduce these variables.

The product uses gravity as a part of the force-bearing system, but it is not a traditional narrow-body gravity valve. The main differences are the wide-body hydrodynamic design and force balance calculations.

The wide-body flow channel helps to improve the back pressure capability and stress conditions, and reduces the risk of the valve disc opening and closing repeatedly, hammering, and colliding with the valve seat under pressure fluctuations.

Common root causes include narrow and high flow channels, insufficient back pressure capability, and excessive area shrinkage ratio. These characteristics can make the valve more sensitive to pressure fluctuations, resulting in repeated opening and closing, hammering and seat collision.

When the valve is opened, the design of EXSAFE strives to bring the upward aerodynamic force and the downward gravity and friction forces close to balance. When the force difference is small, the valve disc movement will be more stable.

Technical evaluation and customization can be carried out within the 5-100 kPa project range, and the final scope depends on the diameter, flow rate, material, classification society certificate and project approval conditions.

A common pressure setting discussed for the EXSAFEP/V valve is approximately 21 kPa. Actual setpoints depend on vessel design, cargo systems and order specifications.

Common vacuum settings may include values such as −3.5 kPa, depending on the model and project requirements. Final values ​​must be based on the nameplate, certificate and approved data sheet.

The backseat pressure difference is the difference between the opening pressure and the closing pressure. Smaller back-to-seat pressure differential helps reduce unnecessary steam emissions and cargo losses.

EXSAFE can achieve a higher opening/closing pressure ratio, and the return pressure differential performance discussed in the data is about 87% or higher. For example, under applicable operating conditions, a valve may open near 21 kPa and close near 20 kPa.

Smaller backseat pressure differentials help reduce vapor losses, improve tank pressure control, and support lower VOC emissions and cargo losses compared to valves that remain open over a wider pressure drop range.

The main sealing interface adopts a metal-to-metal structure, and the sealing contact width marked in the data is 5.5 mm. The actual leakage index should be subject to the corresponding model test conditions and project documents.

Yes. EXSAFE is designed to achieve 0 m³/h leakage under relevant test conditions. Sealing surface design, hardness, contact width and machining accuracy are key to achieving this result.

According to the EXSAFE product characteristic description, the sealing contact width is 5.5 mm.

The sealing surface hardness design value is about 50 to 55, and it has corrosion resistance for marine salt spray environment and oil and gas conditions.

The tapered design facilitates self-centering and improves seal fit, which is important for metal-to-metal sealing performance.

Yes. According to the product characteristics description, EXSAFE has conducted leakage performance tests under a 30-degree tilt state and achieved zero leakage results. This angle of inclination is higher than the laboratory requirements commonly seen in classification society test discussions.

Maximum breather tube length depends on model, size, pressure setting, flow requirements and approved calculations. The EXSAFE wide-body design can improve back-pressure capabilities and support longer ventilation pipeline arrangements than traditional designs under applicable conditions.

The longer the vent tube, the greater the back pressure and dynamic pressure fluctuations generated. Valves with better back pressure capabilities and flow stability are more likely to remain stable on complex ventilation pipelines.

Common materials include FCD, WCB, SUS304 and SUS316L, and the specific available materials depend on the model, size, medium and classification society requirements.

EXSAFE can support FCD material options including FCD450-17, which is subject to the project confirmation results.

FCD/WCB products have good cost performance and are widely used in ship operating conditions. SUS304/SUS316L products have stronger corrosion resistance and are suitable for more demanding working conditions or customer-specified applications.

Yes. EXSAFE can support standard sizes and customized sizes, but they need to be determined based on flow capacity, flange standards, classification society approval scope and engineering review.

Yes. Where technically feasible and subject to project approval, EXSAFE can support custom pressure settings ranging from 5 to 100 kPa.

Yes. As a factory, EXSAFE can provide manufacturing, forging and machining services for non-standard parts, repair parts and project-specific components.

Alternatives can be evaluated. It is recommended to provide the original valve model, nameplate, photos, diameter, flange standard, pressure/vacuum settings and installation drawings.

Magnetic P/V valves use magnetism to improve closure and stability, but the magnets may need to be replaced or inspected periodically. EXSAFE does not rely on magnets, but uses a hydrodynamic structure to achieve stable operation.

Traditional gravity valve structures can be simple and cost-effective, but many narrow-body designs have weak backpressure capabilities and may oscillate. EXSAFE retains the gravity force line and solves the root cause of stability through a wide-body force balance design.

The design of EXSAFE requires more engineering calculations, precision machining and quality control. Its positioning is a higher-performance full life cycle cost solution, rather than pursuing the lowest initial purchase price.

Not necessarily. Magnetic designs can be effective in certain applications. EXSAFE's view is that a well-designed non-magnetic hydrodynamic solution can reduce maintenance uncertainties and enable more stable long-term operation.

P/V valve cost is not just the purchase price. Leaks, VOC losses, hammer damage, repetitive maintenance, magnet replacement, docking delays and field service can all increase the total life cycle cost.

EXSAFE mainly targets problems such as oscillation, hammering, leakage, high maintenance costs, magnet replacement, limited length of breathable tubes, and unstable operation under pressure fluctuations.

The strongest technical advantage is stable non-magnetic operation based on a wide-body hydrodynamic design, combined with metal-to-metal sealing; model-specific testing and approval documents verify actual leakage performance while possessing a small return pressure differential.

It is usually installed by a shipyard or ship repair yard according to drawings, flange standards, pipeline layout, and classification society or customer requirements.

Debugging and training support can be provided according to project arrangements. The specific service scope, costs and on-site conditions are subject to the contract or project confirmation document.

The model, diameter, flow direction, pressure/vacuum set value, flange standard, gasket, fasteners, pipeline cleanliness, hoisting conditions and nameplate information should be checked.

Wrong flow direction, pipeline stress, welding slag, foreign matter, sealing surface damage, incorrect gasket selection and unauthorized adjustment of pressure settings should be avoided.

The magnetless and metal sealing structure reduces some periodic replacement items, but cleanliness, fasteners, corrosion, moving parts and sealing surface conditions should still be checked according to the ship maintenance plan.

It is recommended to carry out appearance inspection, cleanliness inspection, fastener inspection, corrosion inspection, movement inspection according to the ship maintenance plan, and confirm the status of the sealing surface.

No need. The EXSAFEP/V valve does not rely on magnets, so regular replacement of magnets is not required.

The main seal adopts a metal-to-metal structure, so there is no main soft seal ring that needs to be replaced in order to ensure sealing performance.

The data proposes a 3-year warranty for P/V valves and consumable parts support for applicable customers. The final warranty period, free items and applicable scope are subject to the sales contract and project confirmation documents.

According to company policy, EXSAFE can provide lifelong free wearing parts support for qualified P/V valve customers.

According to current service policies and project arrangements, EXSAFE can provide 4 free high-standard maintenance services within 3 years.

Returning to the factory for maintenance and repair can enjoy preferential prices, including a 20% discount policy according to EXSAFE's current service plan.

The information proposes a response within 24 hours, and on-site services are arranged in conjunction with remote diagnosis, spare parts coordination and regional partners. Actual arrival time depends on ship location, visa, transportation and spare parts conditions.

The cooperative service areas listed in the data include Singapore, Malaysia, Indonesia, Vietnam, Turkey, Greece, Dubai/UAE, Azerbaijan and South Korea. Specific available service capabilities need to be confirmed by project.

Please provide ship name, valve photos, nameplate, available certificates, fault description, video, installation location, operating status and emergency level.

The sales and inquiry email address is sales@exsafevalve.com; the after-sales email address is aftersales@exsafevalve.com; the contact number is +86 189 6456 7890.

Please provide valve type, diameter, material, pressure/vacuum setting value, flange standard, flow requirements, classification society requirements, quantity, delivery location and project time.

P/V valves, general marine valves, air caps, regulating valves, filters and pipeline accessories can be combined and evaluated to reduce project procurement coordination.

Yes. EXSAFE can support emergency repair inquiries when product inventory, materials, documentation and logistics can be quickly confirmed.

Yes. EXSAFE is oriented to the international market and can provide support to overseas ship owners, ship management companies, shipyards and agents.

Yes. EXSAFE welcomes qualified regional agents, ship service companies, valve dealers and ship repair suppliers to cooperate.

Please send ship or project information and technical requirements first. EXSAFE can then recommend suitable products, confirm the scope of the certificate, and provide technical and commercial solutions.

Yes. EXSAFE can review existing valve data and propose replacement options, but must confirm dimensional compatibility, pressure settings, classification society approval and installation conditions.

EXSAFE focuses on marine tank ventilation, pressure and vacuum control and fire protection. Its core products include high-speed breathable P/V valves, pressure/vacuum valves, explosion-proof electric P/V valves, breathing valves, flame arresters and related ventilation equipment, and provides testing equipment, spare parts and replacement and transformation support.

EXSAFE is not positioned as a general-purpose control valve or a large-scale catalog of ordinary valves. The main resources are concentrated on marine tank ventilation, pressure and vacuum control, fire protection and related testing and maintenance needs. General marine valves and pipeline matching are evaluated according to project needs.

Portable P/V valve detection equipment can be used to assist in checking valve opening pressure, vacuum response, reseat status and basic functions, depending on the equipment configuration. It does not automatically replace inspections, witnessed tests or certification activities required by classification societies, administrations or ship procedures.

Can assist in confirming valve model, positive pressure and vacuum settings, test preparation, functional inspection and detection equipment selection. Test methods, calibrations, witnessing, acceptance criteria and record formats should follow ship procedures and applicable classification society, flag state or administration requirements.

The selection of flame arrester requires checking the gas group, flame type, installation direction, operating temperature, pressure drop, medium and maintenance conditions. A flame arrester suitable for one gas or working condition may not be suitable for other projects. The applicable test and approval scope must be confirmed before installation.

Data show that Exsafe EM-50A to EM-300A high-speed breathable valve series obtained BV MED Module B EC Type Examination Certificate No. 85660/A0 MED. This approval applies only to the model, configuration, conditions and scope specified in the certificate and approval schedule.

Not equivalent. Module B belongs to the type inspection stage, and the production compliance procedures and other applicable requirements still need to be completed before corresponding declaration and labeling can be made for qualified equipment. Specifically, the certificate schedule, production compliance documents, product identification and validity at the time of delivery should be checked.

This cannot be guaranteed. Proper sizing, good sealing and maintenance can help the cargo tank remain closed within normal pressure variations and reduce unnecessary emissions before the set point, but actual performance also depends on cargo characteristics, set points, leaks, maintenance status and the complete vapor control system.

For product selection, quotation, replacement, P/V valve testing equipment, spare parts and technical support, you can contact pv@exsafevalve.com; for after-sales service, you can still contact aftersales@exsafevalve.com, the phone number is +86 189 6456 7890.

According to the product and project scope, data sheets, general drawings, pressure and flow information, material information, test records, installation and maintenance instructions, spare parts information and related approval documents can be provided. The final data package should be consistent with the actual supply model and certification requirements.