Gate Valve or Ball Valve-Which Is Better

Jul. 06, 2021

Although slab gate valve and ball valve sound very similar, ball valves and gate valves are different in a number of key ways. Consumers are often confused about the actual differences between these two most common valves found on hardware store shelves. There is always ambiguity as to which one is better for our needs, and listening to the hardware store owner's advice or just picking one up casual off the shelf does not solve this confusion. Here we will discuss these two types of valves, what they are, and what applications they are used for.

Figure out the difference between gate valve & ball valve

The main difference between ball valve and gate valve lies in the way they are constructed. They work in a similar way, but are constructed differently that used for different applications.

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Easy shut-off or fine control

Ball valves are called ball valves because they have a stem and a ball. The ball has an opening on the inside. When the valve is open, that opening is aligned with the pipe, allowing free flow. Turning the stem rotates the ball so that the opening is perpendicular to the flow of water, which closes it. 90 degrees of rotation closes the flow. Gate valves have a circular knob that can be turned 360 degrees This means you can control the flow and pressure of the water by turning the knob, not just off and on, like a garden hose with a spigot.

Tips

If you need fine control, such as the flow and pressure of the fluid, a gate valve is definitely the best choice. There are many types of gate valves, such as slab gate valve, wedge gate valve, etc. If there is no requirement for control, just fast closing and opening, a ball valve will fit it perfectly and that is why people called ball valve as just “shut-off valve”, which is also built to provide a good tight seal.

Corrosion resistance varies-but can be solved with materials

Ball valves are very durable and last a long time, even under heavy use or long periods of non-use. They are very corrosion resistant, it's just that as stated above they don't provide fine control. Gate valves are opened and closed by a screw handle attached to the gate, and control of flow and pressure is dependent on the screw handle. Unfortunately the handle is the most susceptible to corrosion at the handle, depending on the material used in the construction, and the fluid or material the valve is exposed to. Choosing a material that is less prone to corrosion, such as brass or stainless steel, will help. Proper material that makes gate valves no more corrosive than ball valves.

Tips

Improvements have been made to the construction and materials of the valve, making the problem of corrosion solvable. If you are concerned that fluids and air will accelerate valve corrosion, pay attention to the materials when you shop or contact gate valve suppliers.

Reduce water hammer

Water hammer can occur when an open valve suddenly closes, causing water to slam, or when a pump suddenly shuts off and water flows in the opposite direction to the pump. Because water is incompressible, the force of water impact causes shock waves to propagate at the speed of sound between the valve and the next elbow in the piping system or within the water column after the pump, which may be characterized by a distinct crashing or knocking sound in the piping immediately after closing. These sudden stops in flow and the resulting increase in shock wave pressure can cause significant damage to the entire piping system, either as a result of a single event or cumulative damage that occurs over time.

Tips

Silent or spring-assisted check valves, equipped with an internal spring, silently move the valve to the closed position before flow reversal, thereby reducing or eliminating the possibility of water hammer. Air chambers are also an effective water hammer solution. These systems consist of a short section of pipe, usually in the form of a tee fitting, with an empty/filled air chamber that acts as a buffer (shock absorber) that expands when water suddenly changes direction. This reduces the magnitude of the impact force that would otherwise be directed towards the pipe.