How to choose the right check valve
Jan. 13, 2025
How to choose the right check valve
The check valve allows fluid to flow in one direction only, blocking its passage in the opposite direction. Fluid backflow can damage circuits, especially hydraulic circuits. These valves can also prevent liquid or steam leaks if there are faults in the pipe structure. They are also installed in sewage pipes to prevent backflow and the passage of bad smells.
With competitive price and timely delivery, Afbv Valve sincerely hope to be your supplier and partner.
Check valves can be found in hydraulic pumps and motors, ventilation systems, pump pipes, hydraulic and pneumatic connections, heating systems, as well as in the evacuation systems of kitchen sinks, washbasins, bathtubs, toilets, washing machines, etc.
There are several factors that will dictate the choice of a check valve. For example, the desired flow rate and speed will determine the size of the valve you need. This must be sufficient for the fluids to circulate easily, without the risk of clogging.
Contact us to discuss your requirements of Electric Bellows Seal Globe Valve. Our experienced sales team can help you identify the options that best suit your needs.
The type of fluid and the size of any solid particles must also be taken into account. In the case of waste water, you will need to opt for a gate valve with a diameter that allows fibrous substances to pass through.
The type of fluid also influences the choice of valve material. For applications with seawater or other types of salt water, you should opt for a valve with stainless steel components. Attention should also be paid to the choice of material for a check valve intended for corrosive fluids or for food use. For example, for acidic fluids, it is crucial to choose a polymeric material suitable for the type of acid in question, as the resistance of different polymers varies depending on the nature of the acid.
In the case of fluids for food use, stainless steel valves are generally used because they are easier to clean and meet hygiene standards.
Swing Check Valves
?
specified in this Advisory BOILER REGULATION ADVISORY
Subject: Use of a backflow Preventer in Boiler Applications
In accordance with the regulatory authority granted by the Boiler, Pressure Vessel and Refrigeration Laws, this advisory is being issued to ensure safety of the general citizenry in the installation, repair and operation of boiler plants which includes the appurtenances, devices, controls or any items that directly or indirectly impacts upon the regulated equipment that could potentially pose a hazard to the public. Specifically this advisory addresses the use of a Backflow Preventer (BFP) in all boiler related applications.
This advisory responds to numerous inquires that have been submitted concerning the position of the Bureau of Boiler and Pressure Vessel Compliance (BB&PVC) on the acceptance of ASME interpretation IV-95-02, future ASME Code addenda regarding BFP, and other written requests for an official determination on the acceptable use of a BFP in boiler applications that fall under the BB&PVC's jurisdiction.
The BB&PVC does not concur with ASME Code interpretation, IV-95-02 and officially declares any future ASME Code addenda allowing such installations as invalid for the reasons that follow. The BFP and the check valve designed for two disparate purposes and made to accomplish two distinct functions. The check valve required by Section IV, HG-705(a)(b), is intended for the sole purpose of preventing the water in the boiler from being forced out under pressure in the event of a piping break or loss of supply pressure. The backflow preventer is intended for the sole purpose of preventing normally contaminated (undrinkable) water found in the boiler from back-flowing into the potable water system as is required by the plumbing codes.
The BB&PVC staff has thoroughly reviewed product information from the manufacturer of a commonly used BFP. According to this manufacturer's documentation and information obtained from their corporate technical staff, their BFP has rubber-to-metal valve internals that would not be able to tolerate an incidental temperature excursion of 250 degrees F without failing. These types of excursions might be experienced by low-pressure boilers during abnormal or malfunctioning conditions and as a result would melt the rubber internal components, which according to the design of the BFP would open the port to the atmospheric vent so as to prevent the undrinkable boiler water from contaminating the potable water supply. When this vent opens it creates an unacceptable event for boiler operation, because the melting internal component in the BFP puts the boiler at risk for dry-firing condition which could result in a catastrophic failure or a boiler explosion.
For obvious reasons, the melting of protective components is not acceptable for safety and contradicts the logical reasoning for the installation of a standard boiler check valve. Acceptable engineering practices requires that the valves, devices, controls and other similar appurtenances or appliances attached to the boiler or that are an integral part of the boiler, be engineered to prevent a catastrophic failure. Clearly, the BFP installed by itself in the potable water supply line to a boiler defeats the practical safety applications meant for the various devices and components used in boiler systems.
The BB&PVC as the jurisdictional authority has determined that the installation of the BFP the way it is presently (#1) engineered, must not be used by itself in the potable water supply line to the boiler as a replacement for the simple design and standard issue metal seated check valve. In addition, when the installation of the BFP is required by the plumbing codes in the potable water supply or makeup line to the boiler, it shall include the standard check valve as the required by the (#2) boiler safety codes and standards. Thus, the required metal seated and standard check valve must be installed downstream of the BFP, and include a shut-off valve next to the boiler and be located downstream of the standard check valve for system isolation and maintenance purposes.
Therefore, in accordance with N.J.A.C. 12:90-4.2(e), where it states that "only standards relating to public safety are adopted by any incorporation by reference as prescribed ect". The BB&PVC has conclusively determined that the ASME Code Interpretation IV-95-02 and any subsequent Code addenda or revisions regarding this Advisory topic is not in the best interest of public safety for boiler operation thus is ruled invalid. Therefore, in accordance with this advisory any standard check valve and shut-off valve found to be installed in any other manner described herein shall be deemed to be in violation of the BB&PVC regulations and the owner will be subject to the monetary per diem penalty assessment until abatement of the violation occurs.
All questions regarding this advisory should be directed to the BB&PVC by calling (609) 292 ; by to the Bureau Chief: by Fax at (609) 984 , or by written request to the address below.
Department of Labor and Workforce Development Labor Standards and Safety Enforcement Division of Public Safety and Occupational Safety & Health Bureau of Boiler and Pressure Vessel Compliance P.O. Box 392 Trenton, NJ -
Signed: Milton Washington Chief, BB&PVC
(#1) The BB&PVC recognizes that technological advances occur that could address the safety concerns of this Advisory and that improvement in the BFP is possible. However, until advances are made in the design of the BFP to address the concerns expressed, this Advisory shall be enforced and in effect until deemed otherwise necessary.
(#2) See ASME Code or any earlier code edition of Section IV, "Rules for Construction of Heating Boilers" at paragraph HG-705 for the installation detailed in this Advisory. Until proven otherwise, this Advisory renders paragraph HG-705 of the ASME Code Addenda and future revisions invalid when the design of the BFP is of the type as specified in this Advisory.
Personally I think the BB&PVC is wrong, and fundamentally cannot do this legally. There has been NO official Code adoption, Nothing has been included in the Registar nor have they responded with any data suporting their position other than alot of mumbo-jumbo as I've written above.
Robert O'Connor/NJ
0 ASME
I finally received a fax from the third party "commissioned" inspection agency. The fax includes a section out of the A.S.M.E Boiler Pressure Vessel Code book. The section reads as follows:
Section (roman numeral) 4 Article 7, paragraph HG-705 a & b
HG-705 FEEDWATER AND MAKEUP WATER CONNECTIONS
(a) Steam boilers. Feedwater or water treatment shall be introduced into a boiler through the return piping system. Alternatively, feedwater or water treatment may be introduced through an independent connection. The water flow from the indepentent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Feedwater or water treatment shall not be introduced through openings or connections provided for inspection or cleaning, safety valve, water colum, water gage glass, or pressure gage. The feedwater pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the return pipe system.
(b) Hot Water Boilers. Makeup water may be indtroduced into a boiler through the piping system or through an independent connection. The water flow from the independent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Makeup water shall not be introduced through openings or connections provided exclusively for inspection or cleaning, safety relief valve , pressure gage, or temperature gage. The makeup water pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the piping system.
Now, on to the "Official" INTERPRETATIONS Volume 36 of the ASME Boiler and Pressure Vessel Code SECTION (roman numeral) 4
INTERPRETATION: (RN) 4-95-02
Subject: Section (RN) 4, HG-705(b) and HG-715(c)
File: BC94-353
Question: May a backflow preventer containing a check valve be used to satisfy the requirements for a check valve per paragraph HG-705(b)?
Reply: Yes
Any questions?
POC for the New Jersey State Boiler and Pressure Vessel Compliance is Milt Washington (609) 292-
Robert O'Connor/NJ
0
specified in this Advisory BOILER REGULATION ADVISORY
Subject: Use of a backflow Preventer in Boiler Applications
In accordance with the regulatory authority granted by the Boiler, Pressure Vessel and Refrigeration Laws, this advisory is being issued to ensure safety of the general citizenry in the installation, repair and operation of boiler plants which includes the appurtenances, devices, controls or any items that directly or indirectly impacts upon the regulated equipment that could potentially pose a hazard to the public. Specifically this advisory addresses the use of a Backflow Preventer (BFP) in all boiler related applications.
This advisory responds to numerous inquires that have been submitted concerning the position of the Bureau of Boiler and Pressure Vessel Compliance (BB&PVC) on the acceptance of ASME interpretation IV-95-02, future ASME Code addenda regarding BFP, and other written requests for an official determination on the acceptable use of a BFP in boiler applications that fall under the BB&PVC's jurisdiction.
The BB&PVC does not concur with ASME Code interpretation, IV-95-02 and officially declares any future ASME Code addenda allowing such installations as invalid for the reasons that follow. The BFP and the check valve designed for two disparate purposes and made to accomplish two distinct functions. The check valve required by Section IV, HG-705(a)(b), is intended for the sole purpose of preventing the water in the boiler from being forced out under pressure in the event of a piping break or loss of supply pressure. The backflow preventer is intended for the sole purpose of preventing normally contaminated (undrinkable) water found in the boiler from back-flowing into the potable water system as is required by the plumbing codes.
The BB&PVC staff has thoroughly reviewed product information from the manufacturer of a commonly used BFP. According to this manufacturer's documentation and information obtained from their corporate technical staff, their BFP has rubber-to-metal valve internals that would not be able to tolerate an incidental temperature excursion of 250 degrees F without failing. These types of excursions might be experienced by low-pressure boilers during abnormal or malfunctioning conditions and as a result would melt the rubber internal components, which according to the design of the BFP would open the port to the atmospheric vent so as to prevent the undrinkable boiler water from contaminating the potable water supply. When this vent opens it creates an unacceptable event for boiler operation, because the melting internal component in the BFP puts the boiler at risk for dry-firing condition which could result in a catastrophic failure or a boiler explosion.
For obvious reasons, the melting of protective components is not acceptable for safety and contradicts the logical reasoning for the installation of a standard boiler check valve. Acceptable engineering practices requires that the valves, devices, controls and other similar appurtenances or appliances attached to the boiler or that are an integral part of the boiler, be engineered to prevent a catastrophic failure. Clearly, the BFP installed by itself in the potable water supply line to a boiler defeats the practical safety applications meant for the various devices and components used in boiler systems.
The BB&PVC as the jurisdictional authority has determined that the installation of the BFP the way it is presently (#1) engineered, must not be used by itself in the potable water supply line to the boiler as a replacement for the simple design and standard issue metal seated check valve. In addition, when the installation of the BFP is required by the plumbing codes in the potable water supply or makeup line to the boiler, it shall include the standard check valve as the required by the (#2) boiler safety codes and standards. Thus, the required metal seated and standard check valve must be installed downstream of the BFP, and include a shut-off valve next to the boiler and be located downstream of the standard check valve for system isolation and maintenance purposes.
Therefore, in accordance with N.J.A.C. 12:90-4.2(e), where it states that "only standards relating to public safety are adopted by any incorporation by reference as prescribed ect". The BB&PVC has conclusively determined that the ASME Code Interpretation IV-95-02 and any subsequent Code addenda or revisions regarding this Advisory topic is not in the best interest of public safety for boiler operation thus is ruled invalid. Therefore, in accordance with this advisory any standard check valve and shut-off valve found to be installed in any other manner described herein shall be deemed to be in violation of the BB&PVC regulations and the owner will be subject to the monetary per diem penalty assessment until abatement of the violation occurs.
All questions regarding this advisory should be directed to the BB&PVC by calling (609) 292 ; by to the Bureau Chief: by Fax at (609) 984 , or by written request to the address below.
Department of Labor and Workforce Development Labor Standards and Safety Enforcement Division of Public Safety and Occupational Safety & Health Bureau of Boiler and Pressure Vessel Compliance P.O. Box 392 Trenton, NJ -
Signed: Milton Washington Chief, BB&PVC
(#1) The BB&PVC recognizes that technological advances occur that could address the safety concerns of this Advisory and that improvement in the BFP is possible. However, until advances are made in the design of the BFP to address the concerns expressed, this Advisory shall be enforced and in effect until deemed otherwise necessary.
(#2) See ASME Code or any earlier code edition of Section IV, "Rules for Construction of Heating Boilers" at paragraph HG-705 for the installation detailed in this Advisory. Until proven otherwise, this Advisory renders paragraph HG-705 of the ASME Code Addenda and future revisions invalid when the design of the BFP is of the type as specified in this Advisory.
Personally I think the BB&PVC is wrong, and fundamentally cannot do this legally. There has been NO official Code adoption, Nothing has been included in the Registar nor have they responded with any data suporting their position other than alot of mumbo-jumbo as I've written above.
Robert O'Connor/NJ
0 ASME
I finally received a fax from the third party "commissioned" inspection agency. The fax includes a section out of the A.S.M.E Boiler Pressure Vessel Code book. The section reads as follows:
Section (roman numeral) 4 Article 7, paragraph HG-705 a & b
HG-705 FEEDWATER AND MAKEUP WATER CONNECTIONS
(a) Steam boilers. Feedwater or water treatment shall be introduced into a boiler through the return piping system. Alternatively, feedwater or water treatment may be introduced through an independent connection. The water flow from the indepentent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Feedwater or water treatment shall not be introduced through openings or connections provided for inspection or cleaning, safety valve, water colum, water gage glass, or pressure gage. The feedwater pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the return pipe system.
(b) Hot Water Boilers. Makeup water may be indtroduced into a boiler through the piping system or through an independent connection. The water flow from the independent connection shall not discharge directly against parts of the boiler exposed to direct radiant heat from the fire. Makeup water shall not be introduced through openings or connections provided exclusively for inspection or cleaning, safety relief valve , pressure gage, or temperature gage. The makeup water pipe shall be provided with a check valve near the boiler and a stop valve or cock between the check valve and the boiler or between the check valve and the piping system.
Now, on to the "Official" INTERPRETATIONS Volume 36 of the ASME Boiler and Pressure Vessel Code SECTION (roman numeral) 4
INTERPRETATION: (RN) 4-95-02
Subject: Section (RN) 4, HG-705(b) and HG-715(c)
File: BC94-353
Question: May a backflow preventer containing a check valve be used to satisfy the requirements for a check valve per paragraph HG-705(b)?
Reply: Yes
Any questions?
POC for the New Jersey State Boiler and Pressure Vessel Compliance is Milt Washington (609) 292-
Robert O'Connor/NJ
0