What is a hydraulic valve and what are the types of hydraulic valves

 

What is a hydraulic valve and what is its purpose

Hydraulic valves control the direction and flow rate of the valve. Hydraulic control valves can be divided into three types they are directional control valves, flow control valves, pressure control valves, and non-return valves. Hydraulic system uses many valves to control the flow of fluids, hydraulic valves regulates flow by cutting off, diverting, providing an overflow relief, and preventing reverse flow. Hydraulic valves are used in hydraulic power packs to direct the fluid to and from the cylinder. Hydraulic valves can be used to control the direction and amount of fluid power in a circuit. So these valves would do it by controlling the pressure and the flow rate in various sections of the circuit. System pressure can be controlled by hydraulic valves. The burden of pump pressure or temperature of the oil before the oil flow to the hydraulic circuit is reduced by using the hydraulic valve.

 

How hydraulic valves are constructed

Mostly all valves have the same structure a valve body, valve spool, and components of driven valve spool movements. Hydraulic valves are available in four types of construction and they are

 

Threaded port type

Sub-plate mounting type

Cartridge type

 

Threaded port type

These valves have threaded ports as the name says, and it is connected by piping. The piping would require space. This design can be considered as an old one so it has many disadvantages like they are prone to leakage and needs more time to fix

 

Sub-plate mounting type

 

This valve is an industrial valve, it is the same as the threaded type and the only difference can be seen in the mounting. These valves have oil ports and they can be seen in the valve’s flat surface. These oil ports are bolted to manifold at this flat surface. The oil ports would match between the holes in the manifold and oil leakage is prevented by using O-ring at each oil ports.

 

Cartridge type

 

This type of construction differs from the above types, their principle and concept are different. Cartridge type valves have better flow and response when compared to the other types. Cartridge valves are economical too.

 

What are the major requirements of hydraulic control valves

Required performance for hydraulic valves

 

Nominal pressure – it is the maximum working pressure allowed by long term reliable work of hydraulic control valve and this is limited by the valve intensity. Certain factors also influence the maximum permissible working pressure and they are reversing reliability of the reversing valve, and pressure regulation of the pressure valve. The nominal diameter is another factor, better flow capacity is achieved by good diameter so maximum flow could be achieved. Valves that have the same diameter would have different nominal flow because of their functions

 

The hydraulic valves must meet certain performance requirements and they are high sensitivity, reliability, and it must not have high noise or high vibration during the operation. Sealing should be better if the valve port is closed and if the valve port is open then the direction valve must have better core stability. High precision is needed while the operation and it must not be influenced by outside interference. These valves must be in small size and should be able to install properly.

 

What is a hydraulic proportional valve

The proportional valve can do the positioning of the spool in many ways. Due to this feature of the proportional valve infinite adjustable flow volume will be achieved by using this valve. This type of valves can be seen in hydraulic circuits that need more than one speed of actuators. These valves are capable to do the flow control of the fluid and speed of actuator and also control over the direction of the fluid flow. These valves are used in the hydraulic section where flow or pressure is needed to be varied. The proportional valves are operated by using DC power.

 

Why valves are used in hydraulic systems

In a hydraulic system, valves perform certain roles they are, control valves capable to control the operation of actuators. These valves would also regulate the pressure by controlling the oil flow. Some valves have multiple functions and are very useful an example of this would be hydraulic proportional valves.

 

What is 4 way 3 position valve and what is a hydraulic valve spool

In a four-way three-port valve there are four ports and three positions and they are manually operated hydraulic control valve. In this valve there is a liver or it can also be called a spool which can be used for the flow direction so when the liver has moved a connection is established between two ports and the flow takes place. So by changing the liver or spools position we can establish the connection between ports and control the flow direction

 

What is an electro-hydraulic valve

The electro-hydraulic valve is a hydraulic servo valve and in this valve, the servo has a device that could be a flapper nozzle or a jet pipe and this device is used to position the servo. Electro-hydraulic or servo valves are used for accurate position control. These valves are used to control hydraulic motors. These valves are very costly so while selecting this valve make sure that you need accurate position control.

 

What is a hydraulic actuator and what is its use

The hydraulic actuator can convert the fluid pressure into motion, according to the signal received. Hydraulic actuators are required when a valve operation needs a large amount of force.

 

What are the types of hydraulic valves and how does it work

In a hydraulic system, valves are used to control the pressure, volume flow rate, and direction of flow. So based on these functions hydraulic valves are classified into pressure-volume or directional control valves.

 

Directional control valves

 

These valves are used to control the flow direction of hydraulic fluid to different lines in the circuit. These valves check the connection or disconnection of pathways with relative motion between the valve core and valve body to meet the requirements of the system. There are certain types of directional control valves they are one-way valves and reversing valves. In the one way valve as the name indicates it allows flow in one direction but not reverse flow. The reversing valves change the flow direction and they cut off or connects oil channels by the relative motion of valve core in the valve body

 

Pressure control valves

 

Pressure control valves control the pressure in different segments in the circuit. The pressure is created because of some flow restriction, if this not checked then it would create many problems in hydraulic components. There are many types of pressure control valves they are pressure relief valve, pressure reducing valve, pressure sequencing valve, pressure unloading valve, and counterbalance valve.

 

Flow control valve

 

Flow control valves are used if we want to control the amount of fluid flowing past the valves. These valves are used to regulate the speed of hydraulic cylinders and motors by controlling the flow rate to the actuator. The needle valve is an example of a flow control valve. In this valve, the flow is controlled by changing the flow area of the port. The orifice can be used for flow control it is a device in the shape of a disk with a hole so the fluid will flow through the hole. This can be used as a flow meter by measuring the pressure drop across the orifice.

What's so Special About Gas Ball Valves?

 

 

Gas ball valves follow the same principles of other ball valves, they are mostly two-piece construction and feature a ¼ turn shut off. That being said, they are not your standard ball valve. Gas ball valves require CSA approval in order to be used in combustible gas applications. In this blog we will explore more about this rating, testing, and some special features of gas ball valves.

 

Ratings make all the difference

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The ratings for gas ball valves are set by CSA. There are different ratings depending on installation location (indoor vs. outdoor) and country (Canada vs. USA).

• Outdoor Gas Ratings

For a gas valve to be installed outdoors it must have CAN 3.16 approval in Canada and BRS125G approval in the USA.

• Indoor Gas Ratings

The CSA gas ratings for indoor approvals are ½ PSI and 5G. Just as it sounds, valves with these ratings can be installed indoors only. Both Canada & the USA use the same ratings for indoor valves. There are two different ratings because they have different applications, the ½ PSI rating is used for valves that are at appliances, while the 5G rating is for valves that are used in household piping systems.

 

Testing Gas Ball Valves

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Working with combustible gas is not something you want to mess around with. Gas ball valves are no exception, they are tested to 1.5 times the stated working pressure. The one exception to this is the CAN 3.16 valves because they already require a much higher pressure. Here is what pressures the valves are tested to for the different ratings:

• ½ PSI - Test Pressure 3 PSIG

• 5G - 7.5 PSIG

• CAN 3.16 125 PSI Valves - 125 PSIG

• BRS125G PSI Valves - 188 PSIG (ANSI B16.33)

• PSIG = Pounds per square inch, gauge.

It is possible for gas valves to have different pressure and temperature ratings under the same CSA approval. Valves with a higher pressure and temperature rating have been tested to the higher ratings upon request from the manufacturer. However, all the valves must have met the CSA minimum test parameters with respect to pressure and temperature as outlined in the standard.

 

Special Features

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• Yellow Handle

Most gas valves on the market have a yellow handle to signify that they have gas approvals. This is not an official fact but can be used as a quick visual indication. Always make sure that the correct approvals are on the valve before using it in a gas application.

• Pilot Tap

Some gas valves have a pilot tapping in them so a pressure gauge can be installed. This is for testing and/or monitoring the system pressure. Having a gauge right in the valve allows for the most accurate pressure to ensure the system is running at its full potential. The tapping is a standard 1/8” female pipe thread or FPT. Valves with a tapping include a 1/8” male pipe thread (MPT) plug with a tapered brass seat which makes a leak proof seal when tightened with a 3/16” Allen wrench.

 

Understanding what gas ball valve should be used for your application comes down to the ratings and where it will be going - do you need it to have ratings for indoor or outdoor use? When working with gas ball valves always consult a trained professional.

We are a industrial ball valves supplier. Please feel free to contact us if you need them!

Pneumatic & Electric Ball Valve - How They Work

 

 

Ball valves can be combined with a pneumatic actuator (pneumatic ball valves) or an electric actuator (electric ball valves) for automation and/or for controlling remotely. Depending on the application, automating with a pneumatic actuator vs an electric one may be more advantageous, or vice-versa. In this article, we will compare the two options. 

• Table of Contents
• Ball valve overview
• Actuator overview
• Pneumatic actuators
• Electric actuators
• Combining an actuator and a ball valve

 

Ball valve overview

A ball valve is a quarter-turn valve that controls the flow of a media by having a hollow rotating ball, as seen in Figure 2. The figure shows the main components of a manual ball valve in a sectional view. When the hollow portion of the ball is in line with the flow (pipe or hose), the valve is open and the media can flow through. The valve closes when the solid portion of the ball is in line with the flow, which is done with a 90-degree rotation (hence the name quarter-turn valve) of the ball.

It is also possible to position the valve between fully open and fully closed, which allows you to regulate the flow more precisely. Typical ball valves have two ports, one for an inlet and one for an outlet. However, three ports (L or T) are also available, and depending on how the valve is assembled and installed will determine how the 90-degree rotation of the ball directs the media flow. Four-port ball valves are possible but rare.

Ball valves have a valve stem, which is attached to the ball and controls its rotation. In Figure 2, the valve stem is connected to a manual handle to actuate the valve. However, the valve stem can also be connected to a pneumatic or electric rotary actuator to spin the stem to open and/or close the ball valve automatically and/or remotely.

 

Actuator overview

A valve actuator is a device that is used to remotely control a valve. If it controls a quarter-turn valve, the actuator is known as a quarter-turn actuator. Instead of a manual lever, you can mount an actuator on the valve to automatically and/or remotely control it. Actuators use a power source to generate the torque that is required to operate (rotate) a ball valve. For most actuators, the power source is either pneumatic, electric, or hydraulic (not discussed in this article). The difference in this power source makes different designs, which each have different advantages and disadvantages for certain applications (discussed below). Aside from the torque generating component, an actuator may have other features such as position indicators and manual override.

 

Pneumatic actuators

Pneumatic actuators control ball valves by the conversion of compressed air energy to mechanical motion. A rotary mechanical motion is required in a ball valve for a 90 degrees turn. Pneumatic actuator ball valves can be single-acting or double-acting. A single-acting pneumatic actuator uses a single compressed air input to turn the valve and a spring to return the valve to the normal position. A double-acting pneumatic actuator has two compressed air inputs to turn the valve and return the valve to the original position.

 

Operating principle

The most common mechanism for a pneumatic actuator for ball valves is the rack and pinion mechanism. This comprises of the rack (a linear gear) and the pinion (a circular gear) (figure 4). The rack is attached to a piston which is pushed by compressed air to achieve linear motion. This linear motion is converted to circular motion by the pinion. The pinion drives the stem of a ball valve to open and close positions.

To control the pneumatic actuator for ball valves, the compressed air is regulated by solenoid valves. Electrical signals from the controller energize the solenoid valve to either open or close positions allowing compressed air to flow through to both piston sides of the pneumatic actuator. The piston pushes the rack which turns the pinion connected to the stem of the ball valve.

 

 

Electric actuators

Electric actuators convert electrical energy into rotary force by the use of an electric motor to turn the ball valve through 90 degrees. They are energy-efficient, clean, and a quiet method of valve control. The electric motor can be powered by an alternating current (AC) or a direct current (DC). It is housed in a robust, compact housing that also contains other components of the actuator such as gearings, limit switches, wiring, etc. The whole assembly is connected to a valve through a compatible connection interface.

 

Operating principle

The electric motor generates a torque, which is transmitted by a shaft connected to the valve stem. This rotates the ball valve. To achieve the required torque, a system of gears is connected to the electric motor shaft. The torque capacity is an important specification for selecting an actuator. It must be higher than the required torque (breakaway torque) to turn the ball valve by a certain percentage often specified by the ball valve manufacturer. The breakaway torque is the minimum torque required to turn the ball valve usually in the fully closed or fully open static positions.

The speed of operation (the response time) of an electric actuator is inversely proportional to the torque of the actuator. The gear system defines the relationship between speed and torque. A higher gear ratio would result in more torque but a lower response time.

Electric actuators can be powered from a 12, 24, and 48V direct current and 24, 48, 120, 130, and 240V alternating current. Limit switches are installed to stop the current to the motor when fully closed and open. Electric motors can be used to carry out modulating control. This is used to accurately position the valve at any point between fully opened and fully closed positions (i.e. between 0° and 90°). This is useful for regulating the flow rate through the valve. A positioning circuit board (PCB) is installed in the electric actuator to modulate the electric motor. 

 

Combining an actuator and a ball valve

Although actuators and ball valves are separate components, they are most often used together. Therefore, it is more convenient to get them as a package to ensure conformity. Combining an actuator with a ball valve gives you an automatic ball valve that can be controlled remotely. The actuator and the ball valve have a connection interface to connect them. The connection interface comprises of a shaft, or stem, to connect the valve ball, and a flange to bolt the actuator to the valve. This interface may be brand-specific or standardized to standards. You can mount a brand-specific actuator on a compatible brand-specific valve. On the other hand, different ball valves and actuators can be interchanged as long as they follow the same standard.

 

Comparison between pneumatic and electric ball valves

The following are some of the comparable features of pneumatic and electric ball valves:

1) Rotation speed
The rotation speed is the speed at which the ball of an actuated ball valve makes a complete rotation (90-degrees). Typically for the same size units, the rotation speed of an electric ball valve is lower than that of a pneumatic ball valve.

2) Life span
The life span of equipment is the time that the unit is fully functional and operational. Pneumatic ball valves have fewer components and are easier to maintain; hence they have a longer life span than their electric counterparts. Electric actuators have several components that need maintenance, like the electric coil, electronic driver, mechanical actuator, etc.

3) Precision
Precision, or modulation, is for units that stop at a partially open point (i.e. 20-degrees open) to more accurately regulate the flow. Both pneumatic and electric actuators are precise in operation, but motorized ball valves have higher levels of precision. An electric ball valve is capable of opening and closing by very precise degrees. Pneumatic actuators carry out modulation by controlling the air pressure at the inlet port. Leaks or pressure fluctuations can easily affect the valve’s position. Electrical actuators, on the other hand, use exact electrical control signals to carry out control. Additional information can be found in our electrical modulating ball and butterfly valves article.

4) Energy consumption
Energy consumption is the energy required by the actuator to rotate the valve. In comparison, the energy consumption of an electric operated ball valve is less than pneumatic actuated ball valves. In pneumatic actuators, the entire air compression system (compressor, filters, lubricators, power, etc.) accounts for their high energy consumption.

5) Fail-safe
This is a safety feature designed to automatically open or close a valve in case of a power failure. It is typically easier and cheaper to feature a fail-safe mechanism on a pneumatic ball valve than on a motor actuated ball valve. Pneumatic acting actuators are very common and make use of a spring to return to the base position and are ideal as a fail-safe solution. Electric actuators with a fail-safe mechanism can operate with a battery or a spring and are usually more expensive than the pneumatic solution.

6) Cost
The cost of a pneumatic ball valve is usually lower than an electric one because the actuator design is less complex. However, this doesn’t take into account the costs of the components of the pneumatic system, such as the compressor, air preparation, pipes, etc. When no pneumatic system is available near the valve, usually electric actuation is preferred. The operation of a pneumatic valve is more expensive in the long run due to the higher energy consumption and energy losses that are a result of generating compressed air.

7) Position feedback
Position indicators indicate the position of the actuator at any given time. They are usually placed atop the actuator for high visibility. Most pneumatic actuators can be equipped with a limit switch on top for electrical feedback. Many electrical actuators have internal limit switches for position feedback. However, more basic actuators do not have this feature.

8) Size/torque range
Torque is the rotary force a ball valve requires to turn. Pneumatic actuators offer a much higher torque per unit size than electric actuators. Therefore, for applications requiring a large valve or high torque typically a pneumatic ball valve is a better option.

9) Hazardous conditions
An electric ball valve has to be NEMA/ATEX certified before it can operate in hazardous conditions. Pneumatic actuators, however, are more widely available with ATEX certification. Also, they neither generate nor are affected by electromagnetic disturbance. Unlike their electric counterparts, pneumatic actuators are not sensitive to wet environments, neither are they subject to overheating.

The Ultimate Guide to Select Swivel Joints

 

 

What is a Swivel Joint?

Swivel joints, also known as rotary unions are used in applications where a constant transmission of fluids from a stationary source to a rotating source is required without cross-contamination or leakage. Typical applications use swivel joints to allow for 360-degree rotation while preserving hoses from getting tangles as components turn. In return, mechanical stresses that would result from hose twisting, bending, and stretching can be relieved.

Swivel joints are engineered to operate at a wide range of pressure and temperature for a variety of conditions and environments. Based on industry requirements, the swivel joint can be designed to have multiple passages and can transfer different types of fluid simultaneously at various rotational speeds. Typically, as the number of passages increases, the size increases, and speed will be lower.

 

How Does a Swivel Joint Work?

Swivel Joints come in different shapes and sizes based on the application and the environment where it is subjected to. While design consideration should be given to external factors, all the swivel joints have two main components: a shaft and housing.

The concept behind a swivel allows the shaft to rotate while the housing remains stationary in position. The shaft has drilled holes of varying size and depth starting from its top surface. Variable hole depths and markings define the flow path of fluid within the swivel. Through internal design, the fluid is carried through the shaft into and out of the swivel joint.

The housing unit includes machined passage and grooves to facilitate fluid transfer within the swivel and preventing cross leaks. Numbered markings are found on the housing outer diameter surface and the same can be found on the top surface of the shaft.

These numbers define where a user would expect the fluid to flow in/out between shaft and housing through the machined internal passages. A series of carefully selected internal components are fitted between the shaft and housing at specified locations. These include seals, snaps rings, O rings, wearings, small bearings in certain applications.

The selection of internal components is of vital importance while designing a swivel joint as extreme attention has to be given to the tolerances and internal design of the housing grooves. Failure to adhere to the recommended design and machining requirements results in leaking components.

Passage of power and signals are sometimes required for particular applications and industries. Slip rings can be integrated with the swivel joint through passing electric cables within the hollow inner diameter of the shaft.

 

How to Select a Swivel Joint?

As opposed to other rotary components in the same industries, a swivel joint mostly endures internal loads while operational. This is a direct result of pressurized fluid flowing within its internal components. To select an appropriate swivel joint, multiple influencing factors must be considered.

The most influencing factor on a swivel joint is the internal sealing solution between the shaft and housing. Very precise tolerances must be maintained during the machining phase to create the required grooves for seals and internal components to be fit.

Seals, o-rings, wear rings, and bearings are inserted within these internal grooves and must be able to withstand the pressures induced by the fluid Swivel joints are rated by the manufacturer as to their recommended operating pressures, temperatures, and speeds.

These values are directly related to the internal components specifications, geometric machining tolerances, and type of fluid used significant design and space considerations must be given for a swivel joint and its ports.

Based on application requirements, a swivel joint may have up to 9 different ports to supply fluid through different passages. A higher number of passageways result in significant size and material increase.  

Swivel joints can be modified in size and port sizes with respect to application requirements. Space restrictions, load requirements, duty cycle, and environmental surroundings all factors that are considered while selecting an appropriate component

Based on the requirement provided Slewmaster will be able to provide the best solution that suits the application.

In most cases, our standard in-stock swivels can be modified to fit into your application, and if required Slewmaster can provide a custom-built swivel that suits your needs. Further, Slewmaster can also cross-reference other manufacturers' Swivel Joint and provide an equivalent solution.

 

What are the Different Applications That Use Swivel Joints?

Due to a wide range of custom modifications that can be applied on a swivel joint, it can be found across many applications. Vacuum trucks and cranes that require their booms to rotate 360 degrees using a slew drive run into the problem of hose bending and tangling.

Introducing swivel joints to the system creates a smooth fluid flow for continuous rotation. Bottling lines use swivel joints to deliver fluid across to the different end locations. Design considerations are given to the different fluid viscosities to determine operating pressure requirements.

Farming and agricultural equipment utilize swivel joints in several ways including herd feeding and waste recycling. Welding and robotic arms often require electric passage and slip rings are used to allow for mobility and electric transmission.

 

How is a Swivel Joint Mounted?

Inspect the swivel joints and make sure that all the connections and passages are clean and free from any physical damage during shipment.

A flexible connection/ hose should always be used while installing a Swivel joint. While mounting the Swivel Joint, ensure that either shaft or housing are mounted in a manner that allows for some movement in order to accommodate any misalignment or run-out during rotation. It is recommended to fasten an anti-rotation arm to the stationary part of the rotary union.

When mounting the shaft and the housing make sure that pipe thread sealant is used on fittings and the fitting is properly tightened. For proper functioning of a swivel, it is required to ensure that the mounting flange or surface should be concentric to the axis of the swivel assembly.

After all, fittings are installed bolt the assembly down using the mounting flange or tapped holes provided on the swivel joint. It is recommended to perform a dry run after the swivel is installed to ensure proper mounting of the swivel joint assembly and to verify that there is an unintended movement of the swivel joint due to misalignment.

High pressure selected seals and internal components contain the fluid from leaking out of the closed system. If any leakage is found around any surfaces of the swivel joint, the manufacturer must be alerted immediately.

6 THINGS TO CONSIDER WHEN PURCHASING A VIBRATING SCREENER

 

 

Vibrating screeners are one of the highly effective units that ease the grading and screening of raw materials of different sizes. The demand for vibration screening equipment is increasing owing to the fact that they can handle complex and low precision material screening and classification easily and quickly compared to similar other products available in the market. There are a wide range of vibrating screeners available in several designs and drive sources for more efficient, more precise screening in food, pharmaceutical, chemical, steel, and mining industries. With so many vibrating screen models available in the market it often becomes a confusing task for the users to make the right purchase. This post is thus intended to provide you with information on how to purchase vibrating screener that rightly suits the purpose, location, and working conditions.

 

The Easy-to-Follow Guide to Vibrating Screener Purchase

There might be several questions bothering you when you look out to buy a vibrating screener. This is because of the multitude of options available in the market. So how to go about purchasing the right vibration screener for your applications. The following points will really help.

Varied Types: As mentioned earlier, when it comes to vibratory feeders, there are several types to choose from. Circular screeners, rectangular screeners and gyratory mechanical screeners are the most utilized forms of a vibrating screener. Each type is designed to serve a specific purpose. For instance, choose circular screeners when your application demands grading/screening minimal quantity of material. However, rectangular screeners are rightly suitable for heavy duty applications, which demand screening of a higher quantity of raw materials. Last but not least, gyratory mechanical screeners are the ones suitable for bulk sorting and grading.

Size of the Screen: It is the screen in the vibrating machine that determines the grading/sorting quality. Choosing a machine with the right screen size, thus holds an important consideration. Available in several aperture sizes, screen in the machine must also be chosen based on the type of raw materials that need to be graded.

Capacity: Consider the production needs and choose a model wisely. It is always a good decision to choose a circular type if there are relatively fewer materials to be sorted and if there is a space constraint at your facility. On the other hand, there is no point of choosing a circular or rectangular screener if you need to sort a large quantity in less time.

Application Areas:There are some sensitive areas like food processing and clean room wherein dust and noise generated by the machine would distract the other operations. Communicate with the manufacturer if you have such special requirements.

Longevity: If your application demands vibrating screeners that are ought to work continuously for a long time, then you must opt for one with a high quality vibrating motor. This guarantees continuous and stable functioning of the vibrating screen equipment without any downtime due to motor from burning and exploding.

Nature of Raw Materials: It is advisable to buy a vibrating screener after analyzing the type of materials to be sorted or screened. Look for the special characteristics of the materials such as high static electricity, strong adsorption, and sanitary requirements before deciding on a vibratory equipment model.

Other than the things aforementioned, you must also check for the following when looking out to purchase vibrating screener.

Cost:

• Maintenance requirements

• Operating temperature and speed

• Performance and operating conditions

• Bearing type and arrangement

• Materials of construction

• Space constraints in the application area

• Installation location (indoors or outdoors)

Once these aforesaid points are analyzed, you will certainly get an idea what to choose. From the variety of options available, you will definitely be left with a very few models that serve your purpose. Hence, the selection becomes simple and to the specific requirements. You can also seek help from the supplier from whom you are sourcing the item. If you are opting to buy a vibrating screener from leading suppliers, then they will surely have a team of experts who can help you locate the right model after analyzing your requirements. One such leading name who can offer you a large variety of vibrating screener along with unmatched customer assistance is Changsong Industrial.

How to Choose Your Hydraulic Fitting

 

 

Hydraulic fittings can connect a variety of materials, including tubes, pipes or hoses to components such as pumps, valves or cylinders. When combining these components, you create a leak free system that hydraulic fluid allows for safe transmission. There’s a multitude of fitting configurations and variations to choose from. So, designers have the ability to change the direction of flow, split flows and alter the elevation of lines. Therefore, we have put together some information on how to choose your hydraulic fitting.

 

What Makes Each Hydraulic Fitting Unique?

There are a large variety of fittings available, including the following:

• plugs

• unions

• elbows

• crosses

The threads of the connections is what significantly differentiates these fittings. In addition, SAE, NFPA and ISO documents can also help you distinguish your standard which will help you confirm the diameter and type of thread your fitting has.

The connection of fittings is possible in the following ways:

• welding

• threaded

• flanged

• barbed

• quick disconnect

• push to connect

• 37° flare

• 24° flare

• staple lock

• face seal

• push-fit

• press fit

With a non-flanged fitting, these products will have a gender of one of the following that join together to form a union:

• male (threads on the outside)

• female (threads on the inside)

 

 

Factors to Consider When Choosing Your Hydraulic Fitting

When deciding on which type of fitting to select for your system, there a few important factors to consider. These include the following:

• working pressure

• vibration

• fitting configuration

• desired attachment

• size of piping

• flow

• material of the conductor or component you are connecting to

• pricing requirements

Equally as important is the use of a seal. The fluid power industry is slowly converting to elastomeric seals to help prevent leakage. However, depending on your application, you must ensure that your seal is compatible with the type of hydraulic fluid flowing through your system. Very few applications will require anything other than Buna Nitrile or Viton.

The majority of fitting types are available in different materials including the following:

• plastic

• brass

• copper

• steel

• stainless steel

• specialty materials

Base your material selection on the fluid flowing through your hydraulic system as well as ambient conditions. Depending on what you need for your application, each material will have different performance characteristics. Often times, the first obstacle to tackle is matching your fitting to a similar material to the conductor or component that you will connect it to.

Another important component is choosing the geometry of your fitting. Generally, the geometry fitting is the alphabet letter the fitting resembles. There are fittings that can change the direction of flow and various increments (45° or 90° elbows [L]), or a swivel that allows two jointed sections the ability to rotate. You can also find fittings that have the capability to split or combine flows with the following:

• run or branch tees (T)

• “wahys” (Y)

• crosses (+)

 

Hydraulic Fitting Dash Sizes

Depending on your system, you may need larger or smaller sizes to fit flow demands. The expression of fitting connection size is typically in dimensionless terms representing 1/16 of an inch.

For instance, if someone calls out a “-0.6 thread,” they man the size is 3/8 or 6/16 of an inch. A “dash 32” size is a 2-inch connection or 32/16 of an inch. Also, the thread type of the fitting will determine the connection sizes.

These are just a few important factors to determine how to choose your hydraulic fitting. Contact us here at Changsong for more information!