Wikipedia about common types of valves
Valves vary widely in form and application. Sizes typically range from 0.1 mm to 60 cm. Special valves can have a diameter exceeding 5 meters.
Valve costs range from simple inexpensive disposable valves to specialized valves which cost thousands of US dollars per inch of the diameter of the valve.
Disposable valves may be found in common household items including mini-pump dispensers and aerosol cans.
A common use of the term valve refers to the poppet valves found in the vast majority of modern internal combustion engines such as those in most fossil fuel powered vehicles which are used to control the intake of the fuel-air mixture and allow exhaust gas venting.
What can help a hydraulic service?
A lot of people every day not remember the existence of hydraulic services. Often, a lot of repairs are made independently, without taking into account that a good specialist would do much better, cheaper and easier. If we want to save yourself time and facilitate such matters, you should know that many of them much simpler solution would be to call a plumber to fix everything for us. Such services Hydraulic help us in case of broken pipes, clogged drain, not localized leaks or other malfunctions that cause discomfort and limit our freedom. Good services quickly deal with them can handle and provide us save time and money.
Wikipedia about plumbing systems
The major categories of plumbing systems or subsystems are:
potable cold and hot tap water supply
plumbing drainage venting
sewage systems and septic systems with or without hot water heat recycling and graywater recovery and treatment systems
Rainwater, surface, and subsurface water drainage
fuel gas piping
hydronics, i.e. heating and cooling systems utilizing water to transport thermal energy, as in district heating systems, like for example the New York City steam system.