The valve body, the disc, the valve stem, and the seat are the only four essential parts of a butterfly valve, which has a comparatively straightforward construction. The valve body, which is made to fit between flanges in pipe systems, houses the valve’s functional components. There are several body kinds, the distinctions of which are covered in more detail in the section on different types of butterfly valve.

The component that spins inside the valve body to act as the flow control mechanism is known as the disc (also written disc), also known as the butterfly. To enhance the performance characteristics of the valve, several variations on the CPVC Butterfly Valve design have used offsets of the disc orientation; additional information on this is provided in the section below.

Types of Butterfly Valves

Butterfly valve can be described in a number of ways, including body style, material composition, and disc alignment. Due to the fact that these kinds are not all mutually exclusive, there is some overlap.

Wafer-style butterfly valve

The valve control components of wafer-style butterfly valve are prepared to be sandwiched between two flanges that, when fitted, keep the valve in place. They often use less material, require less machining, and cost less to make than other varieties of butterfly valve. It’s also incredibly simple to install them. Since wafer-style butterfly valve constitute the majority, the word “wafer” is frequently omitted from the description.

Wafer-style butterfly valve cannot be disconnected from the piping system on only one side since they are placed between pipe flanges using a bolt and nut. Wafer-type butterfly valve repair hence frequently necessitates a system shutdown. When fitted, wafer-style butterfly valve prevent the weight of the piping system from passing through the valve body.

Lug style butterfly valve

In order to fit with the holes in the pipe flanges on either side of the valve, lug-type butterfly valve have a series of projecting lugs around the body of the valve. In certain circumstances, the lugs are threaded to match the bolt thread and may be placed using a bolt from either side into the lug. Bolts from the surrounding flanges can also pass through the lugs. The benefit of lug-style butterfly valve is that they may serve as a dead-end service valve, enabling the removal of downstream piling as needed for repair.

Flanged butterfly valve

CPVC Butterfly Valve with distinct flanges on either end is known as flanged butterfly valve. Two types of butterfly valve are available for this application: single-flanged and double-flanged. The flanges are frequently drilled and tapped to fulfill ASME specifications for pipelines; however, occasionally, they may be offered undrilled.

Welded butterfly valve

Butterfly valve that are designed to employ butt welding installation rather than being installed with detachable bolts via flanges are known as welded valve. They are typically utilized in applications with extremely high pressures or in other circumstances, such as cryogenic systems, where exceptional performance is required.

Lined butterfly valve

Butterfly valve with a non-reactive coating or lining material applied to the inner surfaces of the CPVC Butterfly Valve body are lined butterfly valve. By minimizing friction, the coating enhances the valve’s flow coefficient, shields it from corrosive or caustic substances, and guards against the possibility of fluid valve contamination.

Rubber or polymers like perfluoroalkoxy alkanes (PFA) and polytetrafluoroethylene can be used to line butterfly valve (PTFE). The valve is regarded as a non-wetted valve when the valve body and valve stem are shielded from media exposure. Wetted valve, in contrast, have their body and stem exposed to the fluid flow within the valve. Instead of being forced to select corrosion-resistant materials, as is the case with sanitary stainless steel butterfly valve, lined butterfly valve that offer isolation allow the valve body to be produced out of less expensive materials.

Metal butterfly valve

With metal seat components that can survive the pressures and temperatures as opposed to softer resilient seats or PTFE seats that can be damaged under such operating circumstances, metal butterfly valve are designed for use in high-pressure and high-temperature applications. As opposed to other design types like plastic butterfly valve, they also include metal valve bodies and all metal components, making them ideal for applications needing fire resistance.

Zero offset butterfly valve

Applications requiring low pressure and low temperature employ zero offset butterfly valve. The geometric placement of the valve wafer or disc with regard to the valve body is referred to as zero offsets. The valve disc, stem, and body are all symmetrically aligned in zero offset butterfly valve. In the completely open position, the valve stem passes through the center of the disc, which is centered in the valve body opening, and splits the flow into two equal halves. The drawback of zero offset butterfly valve is that during the whole quarter-turn functioning of the valve, there is persistent friction between the disc and the CPVC Butterfly Valve seat.

Double offset butterfly valve

Double offset butterfly valve because the disc to be offset twice from both the valve and the valve body’s centers. As a result, the disc is no longer seated symmetrically with regard to the opening of the valve body, and the position of the valve stem is out of alignment with the plane of the disc surface. By using the double offset design, the friction between the valve seat and disc that occurred with the zero offset design is eliminated, resulting in a smooth opening and shutting of the valve.

When a double offset butterfly valve opens and closes, the disc only makes little contact with the seat, minimizing friction and wear on the seat material. Double offset butterfly valve can be utilized in high-pressure and high-temperature applications when outfitted with an appropriate elastic metal seat and matching metal disc.

Triple offset butterfly valve

Triple offset butterfly valve preserve the two offsets that are the distinguishing feature of the double offset design while also including a third geometrical modification or offset. The valve body’s centerline is not symmetrical with the seating surface of the disc, which has been machined to have an offset conical shape with a right-angled apex. With contact between the disc and seat only at the ultimate moment of closure, this design can enable frictionless functioning of the CPVC Butterfly Valve during cycling. This eliminates the need to worry about wear and friction between the metal seat material and the metal disc when using triple offset butterfly valve.

Butterfly valve made of PVC are extremely durable, entirely corrosion-, impact-, UV-resistant and lightweight. As a result, this kind of valve is becoming more common in numerous sectors. The production of PVC valve involves liquid chemical processes. Afterward, the finished item is put into a mold and cooked in ovens until it becomes the required shape. Even delicate applications like systems for dust collection can employ this new kind of valve. Please visit the website of Petron Thermoplast and learn more about their exclusive CPVC Butterfly Valve, available online at a very affordable price suitable for your industrial application.

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