Selection Criteria For Check Valves: How To Choose The Right One

The Check valve is amongst the most important industrial valves. It is available in many models of various sizes and dimensions. However, this availability can be confusing for someone trying to buy check valves for an industrial or commercial application. Therefore, leading check valve manufacturers in Singapore suggest that to ensure optimal performance of check valves, it is important to choose them concerning the installation specifications.

Given below are some of the main criteria to consider when choosing check valves:

  • Medium

Most check valves can handle liquid medium like drinking water, water for industrial use, and treated wastewater. Untreated wastewater, sewage, or slurries are likely to cause damage to the valve's internal components. Since the medium will constantly contact the valves, it is important to understand the media characteristics to ensure that it won't affect its operational capacity.

blue with silver colour gate valve installed in the outdoor of our clients industrial unit to control the flow of direction
  • Flow rate

There is one problem with the rapid closing of the check valve's disc. Despite preventing slamming, it cannot protect against the sudden surges when the pump is switched on or off. Sudden opening and closing of the lid are likely to cause unexpected surges.

Also Read : What Are Check Valves?

  • Material

The valve materials must be compatible with the media flowing through them. For example, if the media is mainly water, it is better to choose plastic or stainless steel valves instead of metal valves.

  • Head loss

Head loss is fluid velocity and a combination of the static head caused by elevation difference and friction head caused by the flow disturbances due to the internal pipes. In addition, the valve body's geometry dictates the general body area of the flow through the valve and thereby impacts head loss.

One of the main formulae to counteract head loss is the flow coefficient of the amount of water passing through the valve at a certain pressure and a certain amount of time.

  • Non-slam characteristics

Check valve slam and the resultant pressure surge and common problems that occur from day one. The slam is characterized by an audible caused by a pressure spike that initiates a sound wave by instantaneously stretching the pipe wall. Ideally, a check valve should close before any reverse velocity occurs, but that is not what happens in most cases. Unfortunately, in most check valves, the valve's geometry will decide the amount of reverse flow. The formula is simple: The faster the valve closes, the lesser the slamming.

Slamming is an issue for vertically installed check valves. However, swing check valves are better than their counterparts as far as slamming is concerned.

  • Expenses

The expenses of owning a check valve is a sum of the buying costs, maintenance costs, electricity costs, etc. The total cost of ownership is a lot more than the initial cost of purchase. The trick is to choose a valve of simpler construction to keep the installation and maintenance costs under control. Unfortunately, some check valves surpass the cost of purchase with higher maintenance and energy costs.

  • End connection types

Connection types should be selected based on the connections already available in the
system. A strong and well-fitted connection is a fundamental requirement for a long-lasting valve. The connection types include:

  • Threaded
  • Bolt flange
  • Clamp flange
  • Union
  • Tube fitting
  • Compression fitting
  • Sock weld
  • Buttweld

Other important selection criteria for check valves

Apart from the criteria mentioned above, one ought to keep in mind other aspects while choosing check valves:

  • Pressure drop

The changes in pressure impact the flow control, and thereby the functioning capacity of the valve.

  • Control mechanism

In check valves, the control mechanism can be a disc, a ball, or a poppet. Whatever the type, the control mechanism should effectively prevent backflow utilizing pressure, a spring, or a combination of both.

Customize your check valves with Oilway: Singapore's leading check valve manufacturer

Oilway is a popular industrial valve supplier and manufacturer, offering the finest range of check valves for many industrial applications across Singapore. To know about our products and to discuss your customization requirements, please call our team @+86-21-69891289.

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