A knife edge gate valve is a valve that is used to control the fluid media by either stopping its flow or by limiting it to suit the desired flow operation. Pressure loss is a major problem that is produced by the usage of valves and the gate valve allows a straight-through unhindered passageway for the fluid media thereby leading to minimal pressure drop due to the valve. Unlike the Gate valves, the gate valves allow unobstructed flow and thus, also a passage for the cleaning operation of the pipe, when it is needed. However, on the flip side, the gate valves are slower to operate than the quarter-turn Gate valves. Therefore, in normal operations, the gate valves are operated either in fully closed or fully open mode. Therefore, in most applications, a manual gate valve is used because gate valves are operated intermittently. Gate valves are beneficial in applications that involve the movement of slurries and are also useful in applications involving the transport of viscous liquids such as heavy oils, varnish, light grease, honey, cream, molasses, and other non-flammable viscous liquids. They are offered in big dimensions to handle viscous flow efficiently. Although it is not recommended, the gate valves can be used for throttling applications.
Parts of Gate Valves
There are many parts comprising the gate valve. To get a good and clear idea, let us have a look at the following table for the list of parts and their important functions.
Working of the Gate Valve:
A gate valve works very similarly to the normal working of any other valve. To operate the valve, the hand wheel needs to be operated, or using the actuators, the stem is either raised up or down. When the gate is lifted, it releases the inlet to the outlet permitting an unobstructed passage for the fluid media to flow. When the gate is dropped, it closes and wedges the media flow. The association between the gate's vertical travel and the flow rate is nonlinear for a gate valve, with the utmost changes happening near-complete closure position. You should make sure to choose the best Gate Valves manufacturers that would serve your purpose.
There are many types of gate valves, some of which are listed below,
-Knife gate valve
-Wedge gate valve
-Parallel slide gate valve
-Slab gate valve
-Parallel expanding gate valve
There are many advantages of using a Gate valve over other valves. A few of the advantages include
(i) Low loss of pressure across the valve.
(ii) They are bi-directional and permit uniform linear flows.
(iii) No residues are left in the pipes.
(iv) Gate valves can endure higher pressures compared to butterfly valves
(v) It avoids water hammers because the wedge has a slow operation.
However, it also has disadvantages such as low operational speed, erosion of seat and gate if partially operated, and more expensive due to its large size.
Gate Valve Manufacturers in India:
There are many globally recognized Gate Valves manufacturers in India. The following companies offer the best-manufactured Gate valves.
Larsen & Toubro Valves:
Larsen & Toubro Valves (L & T Valves) are a global leader in Gate valve manufacturing. The company boasts over six decades of industrial experience. They are one of the most reputed brands for Gate valves in India. The company is based out of Mumbai, Maharashtra. The company has precision machining equipment that calibrates and accomplishes critical tests. Therefore, L & T valves are precision made. The company’s gate valves are either bolted bonnet type or pressure-sealed bonnet type with ANSI Class ranging from Class 150 up to Class 4500. The Gate valves are designed in-house using state-of-the-art machines using the advanced CFD software. The company boasts of very strong Gate Valves suppliers and dealership networks and has a strong international presence due to its exporters.
Kirloskar Valves is one of the biggest industrial gate valve manufacturing companies located in Pune, Maharashtra. Due to their high manufacturing standards, their Gate valves are always sought after by many companies worldwide. It is one of the oldest companies in India having over 100 years of presence in the valve manufacturing and supply business. With a strong supply and dealership chain, Kirloskar valves can be purchased anywhere across India and the world.
Amtech Valves Ltd. is based out of Gujarat and they have about four decades of experience in the manufacture of Gate valves. They have expertise in gate valve manufacturing and are known for their superior design and quality. The company boasts of a strong research and development team and its gate valves are used by many companies specializing in power production, sewage treatment, etc. They are reputed Gate Valves suppliers that have a sustainable supply business as well as export to many countries.
Hawa Valves is a Mumbai-based industry and their valves are tested in-house for quality. The valves produced by Hawa valves are manufactured using the most advanced manufacturing practices. Being the best Gate Valves supplier, it has a dealer network across India and the world. The company has over four manufacturing facilities spread across India. Hawa Valves is recognized as an ISO 9001:2008 and OHSAS 18001:2007 compliant company.
KHD Valves Automation is a valve manufacturer based in Mumbai, India. It focuses on flow control valves and produces a wide array of industrial valves like the gate valve. KHD specializes in the manufacturing of knife gate valves, threaded gate valves, and sliding gate valves. Lightweight and easy to connect, all KHD gate valves have an all-out operating pressure of 142 psi. All of their gate valves are made of iron. They have backed by a robust dealership.
Whether you’re a machine expert or someone who is still gaining knowledge about motor device parts, you are most likely aware of the actuator and its significance.
Actuators serve the general purpose of controlling movements within machines. However, there are various kinds of actuators that produce varying motions and use different power sources. Distinguishing the differences between these motion-controlling devices will help you troubleshoot parts or refine the processes within your machine.
Let’s take a look at the different types of actuators and their functions, as well as some tips for keeping them working at peak performance.
What is an Actuator?
An actuator is a machine part that initiates movements by receiving feedback from a control signal. Once it has power, the actuator creates specific motions depending on the purpose of the machine.
What Are Some Devices with Actuators?
Machines and systems have featured actuators since their popularization back in World War II. The most well-known examples of actuators include:
What Are Some Different Types of Actuators?
Actuators can be classified by the motion they produce and the power source they use.
Actuators can create two main types of motion: linear and rotary.
Implied by their name, linear actuators are devices that produce movement within a straight path. They can either be mechanical or electrical and are mostly seen in hydraulic or pneumatic devices. Any machine, equipment, or gadget that requires some form of straight motion typically has a linear actuator.
In a simple linear actuator, there is a nut, cover, and a sliding tube. The sliding tube provides the space for the motion, whereas the nut and cover provide the interlocking movement that keeps the actuator in a straight path. Other complex linear actuators will have additional parts, but the system mentioned above is the foundation for straight movement.
Aira Euro Automation is the leading types of pneumatic actuators. We offer various types of industrial valves like ball valves, butterfly valves, control valves, plug valves, and many more.
In contrast to linear actuators, rotary actuators create a circular motion. From the term “rotary,” most machines use these rotating parts to complete a turning movement. They are often used in conjunction with a linear actuator if a machine requires moving forward, backward, up, or down.
Many rotary actuators are electrically powered, but some are powered using a hydraulic or pneumatic system. You can find rotary actuators in windshield wipers, electric fans, or manufacturing machines that transport goods from one area to another.
Source of Energy
To further distinguish different types of actuators, we can also sort them according to the power source or system they use to move. Below are the most common actuators according to energy source:
Hydraulic actuators operate by the use of a fluid-filled cylinder with a piston suspended at the center. Commonly, hydraulic actuators produce linear movements, and a spring is attached to one end as a part of the return motion. These actuators are widely seen in exercise equipment such as steppers or car transport carriers.
Pneumatic actuators are one of the most reliable options for machine motion. They use pressurized gases to create mechanical movement. Many companies prefer pneumatic-powered actuators because they can make very precise motions, especially when starting and stopping a machine.
Examples of equipment that uses pneumatic actuators include:
Electric actuators, as you may have guessed, require electricity to work. Well-known examples include electric cars, manufacturing machinery, and robotics equipment. Similar to pneumatic actuators, they also create precise motion as the flow of electrical power is constant.
The different types of electrical actuators include:
Thermal and Magnetic Actuators
Thermal and magnetic actuators usually consist of shape memory alloys that can be heated to move. The motion of thermal or magnetic actuators often comes from the Joule effect, but it can also occur when a coil is placed in a static magnetic field. The magnetic field causes constant motion called the Laplace-Lorentz force. Most thermal and magnetic actuators can produce a wide and powerful range of motion while remaining lightweight.
Some actuators are mostly mechanical, such as pulleys or rack and pinion systems. Another mechanical force is applied, such as pulling or pushing, and the actuator will leverage that single movement to produce the desired results. For instance, turning a single gear on a set of racks and pinions can mobilize an object from point A to point B. The tugging movement applied on the pulley can bring the other side upwards or towards the desired location.
Supercoiled Polymer Actuators
Supercoiled polymer actuators are a relatively new addition to the different types of actuators. They are used in robotics and prosthetic limbs as they can replicate the motion of human muscle via a coil that contracts and expands when heated or cooled.
How to Select the Right Actuator
Understanding the different types of actuators is a crucial step in making the best selection for your equipment. Since each kind has its unique purpose and energy requirements, we’ll go over factors that will help you arrive at the best decision.
Power Source Availability
The first thing you have to consider is the compatibility of your power source. If you own an industrial site with an electrical source, perhaps the best choice—and the option with the most selections—would be electric actuators. If there are no electrical sources in the area, or you want a piece of fully functional equipment without electricity, you can opt for pneumatic or hydraulic types.
Another important factor when choosing an actuator is the range of movement that you need for your equipment. Is it linear, rotary, or an integration of both? Custom-made actuators can combine or chronologically create these motions to help you concretize the final equipment.
Some actuators are more precise than others. For example, air brakes are created through pneumatic actuators because air pressure is known to be efficient in the start and stop movements. Other actuators have a larger margin of movement variations, such as those operated through hydraulics.
Any industry that requires a high level of precision for the safety and success of operation should consider actuator types that have specific movements.
Safety and Environmental Concerns
Safety is another factor to consider when choosing an actuator for your equipment. Electrical or thermal actuators should be used with caution in areas with extreme temperatures or conducting hazards. For example, operating electrical actuators close to a water body without sealing or other safety measures may create an occupational hazard.
If your company is also committed to a reduced carbon footprint, you’ll need to note each actuator’s environmental impact. Typically, electrical actuators have little to no carbon footprint.
There are also specific guidelines to follow for industrial actuators in certain areas. For example, locations with a high presence of combustible gases should adhere to the requirements imposed by the National Electrical Manufacturers Association (NEMA).
Maintaining Your Actuator
All equipment requires maintenance. Maintaining your actuators will help prevent major shutdowns, hazards, or loss of productivity. Here are some general tips to keep your actuators in top shape.
Regular inspection: Performing routine visual equipment checks will identify early signs of actuator issues. A mechanic with a keen eye is necessary to inspect for wear and tear.
Replenish and replace: Hydraulic actuators sometimes need cylinder fluid replenishment. Always double-check for leaks and signs of low hydraulic fluid levels. Replace loose or damaged nuts, bolts, coils, or screws in your actuator parts as well.
Measure performance data: In some cases, actuators won’t show external signs of a problem, but you can trace issues through performance. Automated graphs and output computation may be necessary if you want to catch deeper issues.