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Inside Sales Representative

Check-All Valve Mfg. Co. has an opportunity for an Inside Sales Representative to provide customer service and technical support via phone, email, fax, etc, in the industrial valve industry. The ideal candidate will have the ability to work equally well with technical and non-technical personnel internally as well as outside our business organization. 

Position requirements include the following:

  • Work with Company’s Region Coordinators, Manufacturers’ Representatives, etc. to obtain information critical for providing customer solutions.
  • Prepare and submit proposals for products/services in response to customer’s interests, needs, and quote requests.   

The ideal candidate will possess:

  • Minimum High School Diploma or GED.
  • Minimum of 1 year industrial sales experience. 
  • Good verbal and written, communication and organizational skills.

Compensation:

  • Competitive salary commensurate with experience.
  • Excellent health insurance coverage.
  • 401 K with company matching funds.
  • Cash bonus plan.
  • Profit sharing program.

Company paid life insurance and disability coverage.

Send your resume to: [email protected] 

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What You Need to Know about Check Valves and Cracking Pressure

What You Need to Know about Check Valves and Cracking Pressure

Contributor: Check-All Valve Mfg. Co.

Check valves are used in a wide range of industrial processes. While selecting the correct check valve design and materials for your application is important, it can be equally important to pay attention to what differential pressure is required to open the check valve.

Spring-loaded check valves have a spring that is activated by the pressures in the media, which open and close the valve. In spring-loaded check valves the cracking pressure is determined by the spring setting and orientation of flow through the check valve. Swing check valves; however, use a flapper that swings off the seat to allow forward flow and then swings back to the seat when the flow is stopped (Learn more about the differences in spring-loaded check valves and swing check valves). With spring-loaded check valves it may be possible for the spring (and the resulting net cracking pressure) to be tailored to the application. Typically, with swing check valves you are limited to the weight of the flapper or checking mechanism.

Spring loaded check valves can be built with springs to allow flow in any orientation while most swing checks are not suitable for flow vertical up or vertical down through the valve. Additionally, the use of a spring check valve minimizes water hammer.

Ultimately, if you need a check valve that will allow you to select the cracking pressure to meet the needs of your application, then a spring-loaded check valve is preferred.

What is Cracking Pressure?

Often measured in pounds per square inch (PSI), cracking pressure is the difference in pressure between the valve’s inlet and outlet ports. It’s the pressure differential required to “crack” open the valve (the point at which there is a sudden rise in flow). It’s also sometimes called the spring setting. If a cracking pressure is too high the valve will not fully open. If it is operating partially open the valve check mechanism may rattle and chatter, which can cause excessive wear and premature valve failure. This can result in the check mechanism failing to operate, coming apart with components traveling up or downstream (which can destroy valuable equipment), and preventing the function of stopping reverse flow.

Effects of Vertical Installation on the Cracking Pressure

Most spring-loaded check valves have a minimum recommended net cracking pressure; however, the cracking pressure is affected by vertical flow orientation. If the flow direction is vertical down, gravity pulls the weight of the trim components against the valve spring. This reduces the net cracking pressure, which may cause the valve to open or fail to return closed. In these cases, the spring selected must be heavy enough to support the weight of the trim, any column of liquid or media desired to be retained and achieve the minimum net cracking pressure. If you install a spring-loaded check valve in a vertical flow up orientation, then the weight of the trim components would increase the amount of force required to open the check valve. Your net cracking pressure will be the combination of the trim weight, the spring, and any fluid column above the check valve. 

When you’re designing a system for automatic flow control the design of your check valve matters and the correct cracking pressure can be crucial. Working with a manufacturer that can tailor check valves to your application can be the difference between a low maintenance, properly functioning system, or one that requires frequent maintenance and sub-par performance. Most spring-loaded check valve manufacturers offer limited options for cracking pressures; however, Check-All Valve offers spring cracking pressures from 1/8 PSI to upwards of 85 PSI (and virtually anywhere in between).  Check-All has a large selection of in-stock springs, and when those will not suffice the option is available to special order a setting of your choice. With this versatility there is a solution for nearly every application.

See our entire product offering at:

www.checkall.com

References:

https://www.checkall.com/PDFfiles/Catalog.pdf

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What is a Check Valve used for?

Home » Valves

Check valves are a devise that allow media such as liquids, gasses, or steam to flow in only one direction. Also known as one way check valves, they can have a checking mechanism that can be shaped like a ball, disc, piston or poppet. Check-All only manufacturers poppet style spring check valves. The following are some examples of different applications of use.

To Protect Equipment from Backflow Damage

Spring-loaded check valves can be mounted in any flow orientation (with proper spring selection). This particular valve design incorporates a spring to assist in closing the check mechanism and does not require gravity or backflow pressure to function.  When system pressure begins to reduce, flow begins to slow, stop, or even reverse, spring check valves prevent reverse flow. This protects pumps and other equipment from damage caused by backflow.

Spring Check Valves are used in a wide variety of applications for flow control including, line isolation, priming pumps, media injection, maintaining head pressure, and many others. Proper spring selection (spring setting) is very important to assure optimum valve performance. This will also improve the life expectancy of the valve.

Low Pressure Relief Valves

Inline spring-loaded check valves can be used in low pressure relief applications. Utilizing either elastomeric, thermoplastic or metal to metal seals, these valves can be custom-built with spring materials ranging from stainless steels to Titanium, Inconel, or many others. Different spring materials will perform differently depending on their unique properties. The key to pressure relief in this case is that the poppet moves away from the valve seat when the force of the upstream pressure exerts a greater force than that of the spring, allowing the media to pass through the outlet port. When sizing spring check valves for pressure relief applications, it’s important to know the set pressure and the maximum pressure the system can handle.  

Dual Roles as Vacuum Breakers

In general, spring check valves can be used as vacuum breakers. The purpose of a vacuum breaker is to allow air into the piping system for the purpose of preventing the interruption of  the desired flow of liquid. A tank is a common application where a check valve would be installed at the top of the piping to relieve the vacuum when the tank is being pumped down. Another application where these type of valves can function as vacuum breakers is when there is a dramatic change in piping elevation. Vacuum relief valves can also be installed in vacuum systems in order to pull a specific amount of vacuum. Moreover, there could be some thermal applications where the media can change from very hot temperatures to very cold temperatures, and the differences in volume between temperatures is an instance that may require a vacuum breaker to relieve that vacuum when it is created as a result of a variance in temperature.

Engineering spring check valves since 1958, Check-All® Mfg. Co. is an outstanding source for all of your check valve, vacuum breaker, and low pressure relief applications. Use the comments to post your questions or tag us on social media. Stay tuned for our next article!

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Spring Check Valves versus Swing Check Valves

Swing check valves are by far the most common type of check valve in any industry. Typically, they have a lower up front cost, but are also limited in their application and instillation options vs spring check valves. When in use, it’s important to understand the differences between these types of check valves. In this article, we’ll cover some basic differences between these two types of inline check valves. We well also cover the advantages and disadvantages of each.

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1. One difference between these types of check valves is how they allow and prevent flow. A swing check valve uses a flapper that ‘swings’ off the seat to allow forward flow and then swings back onto the seat when the flow is stopped. In contrast, a spring loaded check valve incorporates a spring to assist in closing the valve. Learn more about spring check valves!

2. Swing check valves are limited in the orientation in which they can be installed. These type of check valves can only be installed in horizontal flow applications, which greatly limits the applications where they can be used. While swing check valves do offer a larger flow capacity, they may not always fit in existing piping configurations. On the other hand, spring loaded check valves can be mounted in any flow orientation with the right spring selection. In you need a check valve for a process skid, a difficult space with challenging dimensions, or even unique direction of piping, choosing a spring check valve with the proper spring setting (spring cracking pressure) provides more possibilities for finding the right solution for your specific flow control application.

3. Any water hammering effects present in a piping system can potentially be amplified by a swing check valve. Installing a spring loaded check valve can prevent effects of water hammer; whereas a swing check valve can exacerbate the issue. Spring check valves are considered “silent check valves” by utilizing a spring to assist the poppet in closing the check valve prior to fluid flow reversal. The following is a basic example to explain the concept of water hammer.

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Consider an application where you have a process line with water in it. For flow control you have a check valve and downstream of that check valve you have a lever handle quarter turn ball valve. Let’s say water is flowing and someone shuts the quarter turn ball valve abruptly. This can produce a pressure wave flowing through the piping – this is what is known as water hammer. With a swing check valve specifically, the flapper on that valve will be open until that pressure wave returns back to the swing check. The pressure wave can cause the flapper to slam shut, both of which can contribute to inducing water hammer. Conversely, a spring loaded check valve will help minimize, and in some cases, eliminate the effects of water hammer because the spring in the spring check closes before the pressure wave gets there.

We hope this clears up any confusion you may have around the differences between these different type of check valves and that you learned the advantages offered by spring check valves. All the valves Check-All Valve manufactures are inline spring loaded poppet style check valves. Our expert staff can answer any questions you may have. Use the comments to post your questions or tag us on social media. Stay tuned for our next article!