Showing posts with label block valve. Show all posts
Showing posts with label block valve. Show all posts

Wednesday, September 20, 2017

Trunnion vs. Floating Ball Valves

trunnion mount ball valve for industrial pipeline use
Trunnion mount ball valves have upper and lower support
points for the ball.
Image courtesy International Standard Valve, Inc.
The design, construction, and function of a ball valve is generally well understood in the industrial fluid processing arena. Ball valves provide reliable quarter turn operation, compact form factor, and tight shutoff capability, making the ball valve a preferred choice for many applications. Some ball valves also provide shutoff of fluid flow in either direction. A primary valve trim design feature permits grouping of the many variants of industrial ball valves into two categories, distinguished solely by the way in which the ball is mounted in the body.

Floating ball valves use the seats and body to hold the ball in place within the fluid flow path, with the force of directional flow pushing the ball against the downstream seats to produce a tight shutoff seal. Many floating ball valves are capable of flow shutoff in either direction. The ball is rotated by a shaft connected at the top which extends through the pressure enclosure of the valve for connection to a handle or automated actuator. The floating nature of the ball limits the applicability of this design to smaller valve sizes and lower pressures. A some point, the fluid pressure exerted on the ball surface can exceed the ability of the seats to hold the ball effectively in place.

Trunnion mount ball valves employ the stem shaft and, you guessed it, a trunnion to rigidly position the ball within the body. The shaft and trunnion, connected to the top and bottom of the ball, establish a vertical axis of rotation for the ball and prevent it from shifting in response to flow pressure. The trunnion is a pin that protrudes from the bottom side of the ball. It sits within a bearing shape, generally cylindrical, in the base of the body.

Because of their structural design, trunnion mount ball valves are suitable for all pressure ranges and sizes.They are used by many manufacturers as a basis of design for their severe service ball valve offerings. A trunnion mount ball valve can also be advantageous for applications employing valve automation. Since the ball is not held in place by a tight fitting seal arrangement, operating torque tends to be lower for comparably sized trunnion mount valves, when compared to floating ball valves.

On page 3 of the brochure included below, the exploded view of a trunnion ball valve shows the location of the trunnion assembly.

Whatever your valve application challenge, share it with an industrial valve expert. Leverage your own process knowledge and experience with their product application expertise to develop an effective solution.


Thursday, March 9, 2017

Metal Seated Ball Valves Offer Potential for Long Term Cost Savings

3 piece ball valve with handle
Adding metal seats to a ball valve can extend its service life
Photo courtesy of Flo Tite
The majority of ball valves are provided with one of several elastomeric materials forming a soft seat between the trim, or ball, and the valve body. With the balance of the valve assembly in contact with the media likely to be metal (unless, of  course, it is a plastic valve), the soft seat, because of its properties and location, tends to experience wear and tear and be a common cause for repair or valve performance deterioration.

In fluid process control applications where the media conditions may not, at first glance, warrant the use of a metal seated valve, there may be long term returns to be gained from the added cost of metal seats. The factors that create wear and degradation of soft seats are generally better tolerated by metal seats. Process downtime or man-hours for repair have a cost, so avoiding or reducing the occurrences of repair or maintenance provide a return on the additional expenditure for a metal seated valve that can provide a longer service life.

Many commonly available ball valves are also available with metal seats as an option, or metal seated variants are offered as uniquely identified products. Whatever the case, consider hardening your valve selections with metal seated valves. There are instances where they are well suited to the application and will offer a return on the additional cost.

Share your fluid process control challenges with a valve specialist, combining your own process knowledge with their product application expertise to develop effective solutions.



Wednesday, February 15, 2017

Trunnion Mount Ball Valves

stainless steel trunnion mount ball valve flange connections
One example of many variants for
trunnion mount ball valves
Courtesy HS Valve
A ball valve is generally a well understood industrial valve design. Its simple quarter turn operation, bidirectional sealing, compact form factor, and tight shutoff capability make the ball valve a preferred choice for many applications. The many variants of industrial ball valves can be grouped into two categories, distinguished by a primary design feature, the mounting of the ball.

The two designs are known as floating ball and trunnion mounted ball. Floating ball valves use the seats and body to hold the ball in place within the fluid flow path, with the force of directional flow pushing the ball against the downstream seats. The floating nature of the ball limits the applicability of this design to smaller valve sizes and pressure ranges. A some point, the fluid pressure exerted on the ball surface can exceed the ability of the seats to hold the trim effectively in place.

Trunnion mount ball valves employ the stem shaft and, you guessed it, a trunnion to support the trim. The shaft and trunnion, connected to the top and bottom of the trim, establish a vertical axis of rotation for the ball and prevent it from shifting in response to flow pressure. A trunnion is a pin that protrudes from the bottom side of the ball. It sits within a bearing shape, generally cylindrical, in the base of the body.

Because of their structural design, trunnion mount ball valves are suitable for all pressure ranges and sizes.They are used by many manufacturers as a basis of design for their severe service ball valve offerings. A trunnion mount ball valve can also be advantageous for applications employing valve automation. Since the ball is not held in place by a tight fitting seal arrangement, operating torque tends to be lower for comparably sized trunnion mount valves, when compared to floating ball valves.

Whatever your valve application challenge, share it with an industrial valve expert. The combining of your process expertise and experience with their product application knowledge will yield an effective solution.


Tuesday, December 22, 2015

Multiport Valve Block Demonstration Video

multiport valve block for pharma and food and beverage processing
Stainless Steel Multiport Valve Block
Courtesy Gemu
Industrial fluid processing operations routinely include distribution, mixing, and dosing operations on the path to a finished product. With numerous valves, fittings, pipe sections, supports, and other components required to form the fluid path combinations needed to accomplish the process goal, designs can easily become complex and installations unwieldy. Greater parts count puts upward pressure on the probability and frequency of leakage or other types of failures that will divert resources from otherwise productive tasks.

The traditional method of fluid routing through a process may have involved one or more valve stations consisting of manually constructed piping and valve assemblies with numerous fittings, pipe sections, and support structures. These assemblies are often sizable, due to the nature of their manual assembly and required space allowances for field service and maintenance.
Designers and builders of fluid processing equipment should consider an alternative with some distinct advantages. 
A multiport valve block can combine numerous valves into a single compact unit. By doing this, large counts of fittings, pipe lengths, and supports are eliminated, substantially reducing the parts count and number of potential failure points. Of equal importance is the reduction in the required installation space provided by the compact form factor of  the valve block. There is also potential for reduction of dead leg space and volume of fluid retained in portions of the system.
industrial multiport valve block starts with solid metal block and is machined and polished to finished form
Muliport valve block starts with a solid metal block
which is machined and polished to finished form.
Courtesy Gemu

There are endless configurations of multiport valve blocks that can be designed and configured to match the requirements of simple to highly complex valve networks. Materials of construction range from plastics to stainless steel. Variants are suitable for CIP and SIP operations.

The video below shows real world (not animated) functioning of a demonstration unit designed for a mixing operation. Essentially, a multiport valve block allows the installation of a whole lot of valves in a comparatively small space, reducing parts count and associated risk.

Watch the short video. Think about how this modern and effective method of valve networking can bring benefits to your operation. There is much more application detail available from product application specialists. Share your process challenges with them and work together to generate the best solutions.