Wilhelmsen S-55 AC Unitor S55 Oxygen Flashback Arrestor User Manual

Wilhelmsen S-55 AC Unitor S55 Oxygen Flashback Arrestor

Product Information

The Automatic Flashback Arrestor S-55 AC S-55 OX is a safety device made of brass according to DIN EN ISO 5175-1. It is designed for use with fuel gas and oxygen. The product is BAM-certified with Certification-No.: BAM/ZBF/009/12. The safety device consists of multiple components including a non-return valve, dirt filter, flame arrestor, cut-off valve, and temperature-sensitive cut-off valve.

Components

1. Non-return valve (NV): Prevents gas flow in the reverse direction.
2. Dirt filter: Protects the safety device from dirt particles.
3. Flame arrestor (FA): Prevents transmission of a flame or flashback from the blowpipe into the connected equipment.
4. Cut-off valve (PV): Cuts off gas flow without flashback when extreme back pressure is detected.
5. Temperature-sensitive cut-off valve (TV): Cuts off the gas supply when the safety device overheats due to external flame or flame returning from downstream.

Operating and Safety Recommendations

1. Authorized Operation: The safety device is suitable for use in explosion group IIC, categories of equipment 2G. It determines the safety level of an outlet point in a pipeline or single-cylinder system. It should not be used with compressed air or subsequently installed in oxygen equipment. Each piece of equipment should be connected to a single safety device.
2. Unauthorized Operation: Inappropriate handling and unauthorized operation can result in risks of injury to the operator and damage to the equipment.

Product Usage Instructions

1. Installation:
   • Follow the installation instructions provided with the safety device.
   • Ensure proper connection and secure mounting of the safety device.
2. Commissioning:
   • Verify that the safety device has the correct flow capacity for the intended application.
   • Check for any visible damage or defects before commissioning.
3. Breakdowns:
   • If there is no gas flow, check for any blockages or malfunctions in the safety device.
   • If the red indicator is visible, it indicates a potential issue. Contact the manufacturer for assistance.
4. De-commissioning:
   • Follow the recommended procedures for safely disconnecting and removing the safety device.
5. Maintenance:
   • Regularly inspect and clean the dirt filter to ensure proper functioning.
   • Follow any specific maintenance instructions provided by the manufacturer.
6. Repair:
   • In case of damage or malfunction, contact the manufacturer or authorized service center for repair.
   • Do not attempt to repair the safety device yourself.

Always keep the operating instructions accessible and refer to them whenever using or maintaining the safety device. Follow all applicable regulations and codes of practice for installation and usage of the equipment. Pay attention to important safety recommendations marked in the instructions.

OPERATING INSTRUCTIONS

Automatic Flashback Arrestor

• S-55 AC
• S-55 OX
• in brass according to DIN EN ISO 5175-1 for fuel gas and oxygen.
• BAM certified
• Certification-No: BAM/ZBF/009/12 See overleaf.
• Operating and fundamental safety recommendations
• The safety device has a manufacturer’s label which indicates any special requirements.

Foreword

These operating instructions should serve to make the correct operation and safe use of the safety device possible. Attention to the instructions aids danger to be avoided, downtime reduced and operational life and certification to be increased. The operating instructions should be kept in an accessible place within reach at all times. All persons working with the safety device should read and observe the operating instructions. If in doubt contact the manufacturer. In addition to the specific instructions, there may be mandatory regulations or codes of practice regarding the installation or use of the equipment. Any such regulations should be complied with. All particulars marked must be regarded as important safety recommendations. The safety device meets the requirements of DIN EN ISO 5175-1 and is tested before despatch for safe function.

Description

The safety device consists of a combination of various separate safety elements whose functions are described.
Non-return valve NV
Prevents the gas flowing in the reverse direction to the normal flow.
Dirt filter
Protects the safety device from dirt particles.
Flame arrestor FA
Prevents the transmission of a flame or flashback from the blowpipe passing through the safety device into the equipment connected upstream.
Cut-off of gas without flashback PV
This is caused by extreme back pressure of upstream pressure when equipment is shut off. The symptom is a warning that operating procedures and/or equipment should be checked.
Temperature-sensitive cut-off valve TV
Cuts off the gas supply when the safety device is overheated due to an external flame or a flame returning from downstream.

Operating and fundamental safety recommendations

Authorized operation
The safety device is for use in explosion group IIC, categories of equipment 2G.

• The safety device determines the safety level of an outlet point in a pipeline or a single-cylinder system.
• A safety device that has been used with compressed air may not be subsequently installed in oxygen equipment.
• A single piece of equipment may be connected to a single safety device.
• Check that the safety device has the correct flow capacity for the application.

Unauthorized operation (examples)
Inappropriate handling and unauthorized operation could result in the risk of injury to the operator and other persons as well as damage to the equipment. Some examples: The safety device may not be used with gases in the liquid phase and is not certified for use in temperatures below minus 20 °C and above 70 °C.

• A single piece of equipment may be connected to a single safety device.
• A safety device that has been used with compressed air may not be subsequently installed in oxygen equipment.
• Modification and dismantling of the safety device is not permitted.

Marking

The safety device has a manufacturer’s label which indicates any special requirements!

Installation

Recommendations for operation, maintenance, and repair

• All components coming into contact with oxygen must be oil and fat-free to avoid the risk of explosion.
• Marking of the safety device eg. part number or date of purchase, must not be done with punches or any other method requiring force.
• Check that all connecting threads and seating surfaces are clean and without damage.
• The safety device may only be fitted to clean and tested pipelines.
• After repairing a pipeline it must be blown through and re-tested before safety devices can be re-fitted.
• An isolation valve should be fitted to the pipeline before each safety device.
• Hoses DIN EN ISO 3821 should be fitted with suitable hoseclips EN 560.
• The fitting of the safety device is unconnected with the type of blowpipe in use.
• The connection of two or several working devices (burners) is not allowable.
• The safety device fitted to a pipeline supplied by an acetylene generator may only be used together with an approved gas purifier.
• A dirt filter in the inlet of the safety device is sufficient in pipelines supplied by acetylene cylinders.
• If there is any risk of condensation in a pipeline a moisture separator must be installed.
• Wet and dry safety devices should not be installed in the same pipeline wherever possible.
• When this is impossible to avoid the safety device should be installed in separate parts of the pipeline protected from the entry water.
• The safety device is to be installed at the end of the pipeline – at the beginning of the hose.
• With equipment that is built in or connected permanently to the pipeline the safety device should be fitted into the pipeline as close as possible to the blowpipe (avoid the possibility of overheating).
• After installations, all connections should be tested under pressure for leak tightness to the atmosphere. Suitable leak protection fluids should be used. Leak protection should not be carried out with a naked flame.

Commissioning
Pay attention to the operation instructions for the equipment to be connected.
Breakdowns No gas flow

• Test the isolation valve before the safety device is open.

The red indicator is visible

• If the red alarm mark is seen (5 mm ring at the top of the housing), the pressure cut-off valve is closed and the gas flow is stopped.
• The closing of the pressure cut-off valve could have several reasons.
• The reason is to examine and eliminate.

The lever is not to block!

• a) Backfeeding of gas due to a faulty blowpipe.
• b) Flashback due to insufficient gas flow, check that a safety device with sufficient flow has been chosen. Please check, if a flashback arrestor with an enough high flow is used for the application. Okay, the flashback arrestor could be plugged by dirt from the distribution pipe or by carbon caused by several flashbacks. Also, water can block the flame arrestor. The safety device is to be repaired by the manufacturer.
• c) A leak between the ball valve before the flashback arrestor and the non-return valve of the flashback arrestor. The pressure disappears over the leak in the atmosphere if the ball valve before and behind the flashback arrestor is closed and the system is under pressure. The pressure cut-off valve closes at a pressure difference of max. 1.2 bar between the pressure before the flashback arrestor and the pressure behind the non-return valve. This could be caused by a leak between the ball valve and the flashback arrestor. The flashback arrestor is to release the pressure and the leak is to be eliminated before the flashback arrestor is reset. If it is not possible to reset the flashback arrestor the temperature cut-off valve is activated. If so the Flashback arrestor has served its purpose and will have to be deposed off.
• d) The temperature-activated cut-off valve and the gas flow cut-off have operated. At the same time, the red alarm mark could be visible. There is nothing to indicate that the temperature-activated cut-off valve has operated. The backburn has stabilized internally or the ambient temperature is too high.

De-commissioning

• In the event of an outlet point not being used for a long time carefully close the isolation valve before the safety device. At the outlet connection fit a threaded blanking plug.

Maintenance

• Annual testing of the non-return valve, leak tightness, and flow capacity is recommended. The test may be carried out by the operator and must be documented. See overleaf.

Repair

• Repairs may be only carried out by the manufacturer.

49.0
10.0| for air|
15.0| (20 °C)|
74.0
20.0| 99.0| |
25.0| –| |

Conversion factors

• Acetylene x 1.04
• Butane x 0.68
• Natural Gas x 1.25
• Ethylene x 1.02
• Methane x 1.33
• Propane x 0.80
• Oxygen x 0.95
• Town gas x 1.54
• Hydrogen x 3.75

Maintenance guidelines for Unitor Flash Back Arrestors S-55, W-66, and 85-10
The manufacturing date of the Flash Back Arrestors S-55, W-66, and 85-10 is engraved in a code on their cylindrical sides. It is also stated as MM/YY on the outer packaging,

Maintenance guidelines for Unitor Flashback Arrestors S-55, W-66 and 85-10

• Unitor flashback arrestors do not require specific maintenance unless the operator suspects malfunctioning or improper operation.
• Regular maintenance checks of Unitor flashback arrestors can include inlet filter cleaning and checking the functioning of the non-return valve (checking for backflow by applying dry Nitrogen).
• It is advised to routinely check the inlet filter.
• Flashback arrestors should be replaced every 5 years because the internal condition of the flame arrestor is difficult to judge (also refer to OCIMF SIRE VIQ 7 for Tankers and related vessels).

Annual verification guidelines for Unitor Flashback Arrestors S-55, W-66, and 85-10
S-55, W-66, and 85-10 arrestors’ Instruction Manuals recommend annual Functionality Tests (leak test, back pressure test, and flow test). These are our recommendations, please observe these steps:

• Leak tightness of S-55, W-66, and 85-10 body is normally done together with either the AC-OX fixed system annual leakage test or as a test of the standard assembly including the R-510 regulator. Working pressure is applied. Soapy water is applied externally.
• The back Pressure function is verified by applying 1-2 Bar compressed Nitrogen in the reverse direction.
• Flow Test normally requires dedicated and regularly Certified verification equipment, and it is physically impossible to implement Flow Test within on-board conditions.

Immediate replacement reasons for Unitor AC and OX Flash Back Arrestors are required when:

• The flashback arrestor body does not pass the leak tightness test or back pressure test at the working pressure.
• It is faulty, it is older than 5 years, or it is corroded.
• The Flashback Arrestors and Welding Gas Regulators must be replaced every 5-year interval (also refer to OCIMF SIRE VIQ 7 requirements for Tankers and related vessels).

Template for registration of the annual inspection of flashback arrestors:

Flashback

Arrestor

| Location /

Application

| Gas

Type

| Manufacturing

Date

| Inspected

By

| Inspection

Date

|

Sign

|

Remarks

---|---|---|---|---|---|---|---
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |
| | | | | | |

SAFETY PRECAUTIONS

SAFETY PRECAUTIONS FOR GAS REGULATING EQUIPMENT VERIFICATION- BOARD:
The use of compressed air (probably with oil traces), for testing and/or for cleaning is a source of problems because later compressed pure oxygen will react violently with these minor amounts of oil. Other safety risks are the use of copper adaptors for acetylene, non-approved secondary pressure hoses, use of faulty pressure regulators, or even not using a pressure regulator and thinking that throttling the pressure by a shutoff valve is possible. Even properly organized guidelines and documentation is not a guarantee against “the human factor” influence. Always follow the instructions of the manufacturers/suppliers in detail, as they have experience in handling these products.

DECLARATION OF CONFORMITY

For a full copy of the Certificates, please download from https://www.wilhelmsen.com/product-catalogue/. or contact your nearest Wilhelmsen Ships Service Representative
Datasheets, User Instructions, Product Videos, and Catalogue are available at https://www.wilhelmsen.com/product-catalogue/. BAR-9013-GB / 210428

References

• Product Catalogue

Read User Manual Online (PDF format)

Download This Manual (PDF format)

Download this manual  >>