Alternatives to hydraulic circuits

 A good alternative to using a hydraulic circuit would be using a pneumatic circuit. Pneumatics is the use of pressurized gas in an enclosed circuit to perform a specific function. Because of the benefits that pneumatic circuits offer over hydraulic circuits they are becoming more widely used today in different industries. 

These benefits include initial low cost, cleaner then hydraulics, and easy storage of air because it is compressed. Another benefit of a pneumatic circuit is that the motor that powers the compressor doesn’t always have to be running; it only runs when the compressor is on. 


The basic components that a  pneumatic circuit needs are a compressor to compress air, a tank to store the compressed air, a pressure switch to turn off the compressor when the desired amount of air pressure is reached, a check valve to stop air from getting back into the compressor, a safety valve to stop any over pressure getting into the circuit, a pressure gauge to observe circuit pressure, and lastly a circuit to perform a desired function. Some of the different actuators that use pneumatics are air motors and air cylinders. Air motors produce rotary mechanical motion while air cylinders produce linear mechanical motion.

Pipes, Hoses, and Tubing.

Pipes, hoses and tubing are the components that connect all the different components of a hydraulic circuit. Pipes are used primarily for long lasting installations. Hose are used more often for going around sharp bends and corners. One disadvantage of using a hose is that they tend to shrink while under pressure. 


One advantage to using hoses as apposed to pipes or tubing is that they are easily removed and quickly replaced. Steel is the most suitable material for hydraulic pipelines. Copper and galvanized steel shouldn’t be used due to the fact that they both react poorly with hydraulic fluids. Galvanized steel also has the potential to flake causing debris to get into the hydraulic circuit. A disadvantage to using pipe is that it can’t be bent due to the thickness of its walls. 


Tubing has thinner walls then pipes allow it to be bent instead of having to use pipefittings. When installing tubing it should always have a bend in it, this helps to reduce vibration from one component to another. When installing hoses make sure to avoid sharp bends in it. Allow for a little extra material due to the hose decreasing slightly when under pressure. If this isn’t taken into consideration the hose might fail prematurely.

Displayed below are the hydraulic pipelines in an airplane wing. 

Preventative maintenance

Proper machine and fluid maintenance is key in extending the life of any hydraulic machinery. To help accomplish this there should be scheduled preventative maintenance preformed at periodic time intervals. Preventative maintenance helps with reducing costly downtime and it also helps catch small problems that can later turn into bigger ones. 

When performing preventative maintenance it is crucial that you follow the manufactures recommendations. Contamination of any sort, be it from dirt, sand, and anything else could cause damage to the hydraulic circuit so cleanliness is imperative. As I have stated before the heat and pressures associated with hydraulic circuits and cause severe injuries if they aren’t properly dealt with. Before any maintenance is done one must be sure that all power supply to the circuit is turned off. 

The power supply is not only electrical but also hydraulic power sources such as cylinders and accumulators. Make sure the proper lock out/ tag out/ block out labels are applied to the power supply to let other personnel know not to turn it back on. You don’t want someone else unknowingly turning on the machine while you are working on it. Replacing filters and seals at a regular time interval is also a vital part of any

Safety!!

Safety is the most important component of any hydraulic circuit. If safety protocol and regulations are not followed serious injury or death could result. There are numerous examples of technicians or maintenance workers trying to take circumvent these regulations and resulting in injury. 

 Let’s examine one of these examples. A diesel mechanic was severely injured as a result of an accident he suffered while replacing a hydraulic hose assembly on a front-end loader. He was found crushed between the lift arm assembly and the front axle. He was apparently replacing the hose which transported oil from the control valve to the cap-end of the cylinder. He was positioned in the only location from which the hose could be accessed.

The reason for the accident was because the mechanic thought that if he had the bucket on the ground and the parking break on nothing could move. When he went to unscrew the cylinder to remove the hose he didn’t take into account that cylinders can move due to gravity as well, which is what happened and this intern crushed him in between the front axle and lift arm assembly. The mechanic should have supported the front end load from the underside so that the bucket could have never moved. Safety should be a constant concern on everybody's mind.