# hydrostatic lock
## English
### Noun

hydrostatic lock (countable and uncountable, plural hydrostatic locks)
* (mechanical engineering, usually uncountable) A condition that arises when a device which compresses gases seizes up because of the infiltration of liquid, which prevents further compression.
** 1992, US Department of the Army, Operator's Manual: Armored Reconnaissance/airborne Assault Vehicle, Full-Tracked 152-mm Gun/Launcher:When hydrostatic lock is suspected or exists, stop cranking immediately and notify unit maintenance.
** 2014, Barry Hollembeak, Today's Technician, →ISBN:If the engine does not rotate, it may be seized due to its being operated with no oil, broken engine components, or hydrostatic lock.
** 2015, Gus Wright, Fundamentals of Medium/Heavy Duty Diesel Engines, →ISBN, page 328:Cavitated liners can also leak combustion gases into the cooling system, but they tend to produce hydrostatic locks after the engine is shut down when hot.
* (countable) A lock for raising and lowering boats on a canal or waterway that operates by using pressurized water to flood or drain the level inside the lock.
** 1830, Theodore Dwight, Henry Dilworth Gilpin, The northern traveller, and Northern tour:After an empty boat has been once weighed, she is numbered, and her weight is registered at the several hydrostatic locks.
** 2005, Diane Goodspeed, Family-Friendly Biking in New Jersey and Eastern Pennsylvania, →ISBN:This navigation system was possible due to Josiah White's invention of hydrostatic locks, which increased the river depth by creating small artificial floods.
** 2007, Marie Murphy Duess, Colonial Inns and Taverns of Bucks County, Pennsylvania, →ISBN:The canal employed a series of hydrostatic locks—also called bear traps—that would create an “artificial flood” that changed water levels, allowing the barges to flow freely in either direction.
* (countable) A locking mechanism that uses hydrostatic pressure in order to achieve a seal.
** 1894, William Williamson, Mining Notes and Formulæ for Students Preparing for the Colliery Manager's And Science and Art Department Examinations:The different systems are :—The set screw, lead rivet, padlock, pneumatic lock, magnetic lock, cryptograph lock, and hydrostatic lock.
** 1973, Food Engineering - Volume 45, page 68:Hydrostatic locks are being successfully employed in tower cookers, and have been demonstrated to be sound in reduced size form from an engineering standpoint.
** 2010, Ryzhard Pohorecki, John Bridgwater, M. Molzahn, Rafiqul Gani, Crispulo Gallegos, Chemical Engineering and Chemical Process Technology - Volume V, →ISBN:Vertical sterilizers use hydrostatic locks on inlet and outlet sides. Packages are placed in transverse carriers attached to twin roller-chains, which move through the sections of the hydrostatic sterilizer.

### Verb

hydrostatic lock (third-person singular simple present hydrostatic locks, present participle hydrostatic locking, simple past and past participle hydrostatic locked)
* To seize up because liquid has infiltrated a mechanism for compressing gasses.
** 1990 November-December, Jack Chamberlain, “Bedding Your Boat Down For The Winter”, in WaterSki, volume 12, number 9:Do not pour the top lube into the carburetor too rapidly because hydrostatic locking can occur.
* To form a seal by employing a mechanism that uses hydrostatic pressure.
** 2010, Enrico Savazzi, Digital Photography for Science, →ISBN, page 191:It allows a very precise positioning of the light source, thanks to its hydrostatic locking mechanism.

### Derived terms

* hydrolock

### Related terms

* air lock
* vapor lock
* vapour lock