{"id":5858,"date":"2020-08-19T16:59:51","date_gmt":"2020-08-19T21:59:51","guid":{"rendered":"https:\/\/www.anythingflows.com\/en\/?p=5858"},"modified":"2020-10-03T09:43:48","modified_gmt":"2020-10-03T14:43:48","slug":"everything-you-need-to-know-about-how-control-valves-operate","status":"publish","type":"post","link":"https:\/\/www.anythingflows.com\/en\/everything-you-need-to-know-about-how-control-valves-operate\/","title":{"rendered":"Everything You Need to Know About How Control Valves Operate"},"content":{"rendered":"

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Everything You Need to Know About How Control Valves Operate<\/h2>\n

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Water, oil, gas, and more drive industry. Without a network of pipes to flow through, everything would be at a standstill. The city of Los Angeles alone delivers some 167 billion<\/a>\u00a0gallons of clean water a year to customers.<\/p>\n

What do industry giants Kraft Velveeta, Coca Cola, or Pacific Oil and Gas have in common with the city of Los Angles?<\/p>\n

They all use control valves<\/a> to\u00a0regulate\u00a0the motion of liquids or gases through\u00a0their systems. Although\u00a0liquid cheese, sugar syrup, and natural gas are very different, the mechanisms that control their flow are similar.<\/p>\n

Read on to learn about different types of valves and how they work.<\/p>\n

What’s Your Process Loop?<\/h2>\n

If you are moving a product, there may be hundreds of points where there is some important variable that needs control. Pressure, flow, temperature, level, etc. all have effects on your end result.<\/p>\n

One little\u00a0disturbance in a variable can change other points, which in turn affects the next loop.\u00a0Valve controls\u00a0manipulate fluid flows to limit changes. They limit\u00a0process variability and increase efficiency.<\/p>\n

Rotating Types of Control Valves<\/h2>\n

Valves can be automated or operated manually. There are several different types, each suitable for certain uses. control valve body types. We can divide them into two groups: linear and rotating.<\/p>\n

Rotating control valves have an element that turns within the\u00a0flow to modulate it.<\/p>\n

Full or Segmented Ball Valves<\/h3>\n

A rotating control valve suitable for on\/off service, wide pressure and flow variability.\u00a0Segmented ball valves are appropriate for slurry.<\/p>\n

Ball valves<\/a> can be used to modulate the flow of fluids. The ball acts as a plug, which stops or allows full or partial flow through the valve.<\/p>\n

The cost is between globe valves and butterfly valves.<\/p>\n

Butterfly Valves<\/h3>\n

A\u00a0lower cost and less precise alternative to other types of rotating valves. They use less space and are available in large diameters. It is a ring-shaped, inline valve\u00a0with a disc in the middle, that works\u00a0as the plug.<\/p>\n

Plug Valves<\/h3>\n

Another lower-cost alternative to ball valves. Used at low-pressure drops under high flow rates.<\/p>\n

Linear Control Valves<\/h2>\n

Linear control valves use the straight-line motion of a sliding stem to\u00a0adjust flow.<\/p>\n

Globe Valves<\/h3>\n

Globe valves are a linear control valve.\u00a0 They come in three basic types: single-seat, double-seat or three-way.<\/p>\n

Good for a variety of flow characteristics and provide precise control of flows. Best for clean fluids. Tends to be the most expensive choice.<\/p>\n

Gate Valves<\/h3>\n

A type of linear control valve also known as a knife or guillotine\u00a0valve. Used for isolation or cutoff. Not suited to modulate or throttle flow.\u00a0Usually, they block low-pressure gas and airflow. They come in single and double seat versions.<\/p>\n

Pinch Valves<\/h3>\n

These valves are\u00a0suitable for abrasive or corrosive fluids. They are used for\u00a0on\/off service and\u00a0modulation. Air pressure provides the action to collapse the sleeve closing the valve.<\/p>\n

Pinch valve\u00a0construction prevents leaks and forms an excellent seal.\u00a0Selection of the right valve for your control loop is only part of the task.<\/p>\n

Valve Size Selection<\/h2>\n

Many valves are oversized for the process they control. Under normal operating conditions, they\u00a0are at a low percentage of their rated flow capacity. Valves that are oversized deliver less precise adjustments than correctly sized valves.<\/p>\n

This may be to adjust for expected failures in previous process loops or engineering inexperience and error. There are more than 30 pieces of information to collect to calculate the correct\u00a0type, size, and characteristics\u00a0of your control valve. For example:<\/p>\n