fix safety valve pressure cooker made in china

Multi Food Processing Pressure Cooker 4L to 12L All Size High Quality Pressure Cooker All in One, Pressure Cooker Parts Pressure Valve China Manufacture

Pressure cooker valve,the float is made of stainless steel and the seal​ is made of flexible 100% food grade silicone, tasteless and non-toxic, safe for use.

The safety valve on a pressure cooker is a plug made of alloy and a soft rubber gasket. In the event that too much pressure builds up inside the cooker

We are all familiar with different stress. We are under the pressure of the atmosphere every day. We just don"t feel it because of the air balance in our bodies. In our daily life and industrial production, pressure has brought us great convenience.

Each Pressure cooker has a safety function, that is the safety valve, the early safety valve was melting plate type, now the new safety valve is all spring. When the pressure in the pot exceeds the safety limit, the safety valve will be forced by the air pressure jacking exhaust, to protect the safety of users....

No, only if we use it correctly, it is safe in our life. One of the vital things is properly using the pressure limit valve, the pressure limit valve has two kinds, one is adjustable often used in the electric pressure cooker.

1. Check the pressure limit valve and float valve, and check whether the pressure cooker can be buckled in place and whether the gasket on the cover is yellow. If there is any blockage, clean it immediately and do not use it if the mouth is not closed tightly.

When the pressure in the pot to limit the weight of the valve (or spring valve), the pressure limit valve began to reduce pressure, so as to achieve constant pressure in the pot.

At present, most of pressure cookers in use remain old-fashioned pressure cooker the earliest, the safe servicing unit that does not have other except a slice safety plate on the pot cover, when reality is used, must the cooling pan body or take off pressure limiting valve and emit a steam in the pot, after making pot inside and outside air pressure balance, just can open pressure cooker cover, open pot cover else if by force, steam in the pot can be with the unexpected jack-up of pot cover, cause the injury of human body or to the damage of other article, owing to there is not reliable safe servicing unit, this situation happens occasionally.Now new national standard is put into effect, the interior pressure of pressure cooker pot was less than 5KPa when the He Hegai that more requires to uncap was not in place, at this problem, many pressure cooker manufacturers have increased the safety device of pressure cooker open and close cover successively, its basic technical scheme is all increasing a self-locking mechanism between the lower handle on the usual pressure pot, this self-locking mechanism is mainly formed by being contained in the safety valve on the pot cover and being contained in the movable guide plate in the upper handle and promoting restoring mechanism, when still having pressure in the pressure cooker, the spool of safety valve is at steam pressure effect float downward, stretch into the aperture on the movable guide plate, it can"t be moved and self-locking, thus the generation of the action of stopping to uncap by force;

The patent No. is that ZL94206278.7"s " pressure cooker use safeties " utility model patent discloses a kind of like this scheme of self-locking mechanism: by being contained in the safety valve (also can be described as latch gear) on the pot cover and being contained in the movable guide plate (push pedal) on the upper handle and promoting restoring mechanism, safety valve is made up of rubber seal seat and dress valve rod moving up and down within it, when still having pressure in the pressure cooker, the safety pole of safety valve pushes up under the steam pressure effect, stretch into the aperture in the push pedal, push pedal can"t be moved and self-locking, thus the generation of the action of stopping to uncap by force.But is pointed in 95225443.3 the patent application formerly " cover closing and opening safety device for pressure cooker " as us at application number, there be 1. automatically replying owing to spring of following defective in this scheme, so pressure cooker is when uncapping, after needing to overcome spring force with the finger push push pedal earlier, the dislocation that just can carry out next step action of uncapping; 2. its safety valve adopts rubber and seals with the face way of contact, and poor sealing performance runs vapour easily; 3. the chute complex structure on the lower handle; 4. upper handle directly is fixed on the pot cover periphery by two pieces of screws from inside to outside, and is easily loosening, and the secure fixation of upper handle, whether whether lockpin hole is aimed at be directly connected to safety valve can operate as normal.And handle arrangement complexity generally, the user is difficult to install voluntarily, just can dispatch from the factory after must integral installation good, and this has increased packing and freight again;

Our above-mentioned designed such scheme in first to file for this reason: 1. movable guide plate and promote automatic link gear between the skewed slot that restoring mechanism is designed to the movable guide plate of upper handle and lower handle, folding lid action is hand push and settling at one go additionally, and is consistent with the use of conventional pressure cooker; 2. the face seal form of improving safety valve is an O type circle seal form; 3. design special butterfly type upper handle seat, realize that the installation of upper handle is consistent with lower handle---promptly adopt traditional screw to install and fix mode from outside to inside.But find that in actual use this scheme still exists such defective: for reliably fixedly upper handle need fix with two pieces of short screws and butterfly upper handle seat, make install inconvenient; Because the O RunddichtringO is harder relatively, after being stained with rice grain, cause race vapour easily in addition.

Such a valve assembly is known from German laying-open print DOS No. 2,606,676. The pressure relief means thereof consists of a check valve which also serves as a safety valve. It has a valve housing of a resilient material which is fitted into a hole in the cover in the vicinity of the cooking valve aperture. The closure body is designed as a shaft-shaped valve body, transverses the valve opening and supports two spaced valve disks inside the cover as well as a dome-shaped head outside the cover. The head abuts against the valve opening in the pressureless state. As the pressure builds up in the pressure-cooker, however, the valve body is lifted and the upper valve disk closes off the valve opening internally so that the pressure in the cooker can build up. When the pressure becomes excessive, the upper valve disk can move outwardly through the valve opening of the valve housing. This allows steam to escape through the valve opening. The second valve disk preventing the valve body from being blown off the cooker although it does not obstruct the escape of steam. The cooking valve usually comprises a spring-loaded valve and a displaceable pressure indicator for the cooker which is located therein and is also spring-loaded. The springs press against the interior of a cap which is adapted to be screwed on to the valve housing. In the known valve assembly, the cap of the cooking valve has an asymmetrical design on the underside facing towards the cooker cover. It features a guide bevel at this location which reduces its clearance height. In the normal cooking position, the area with the maximum inner clearance height overlaps or overlies the check valve. When the cap is screwed off, the area with a minimum clearance height comes to lie above the check valve over which it can move without obstruction when the head of the check valve abuts against the outer side of the valve seat in the completely pressureless state. If the check valve has closed due to the internal build-up of pressure in the cooker, ie if the upper valve disk abuts against the valve seat, the guide bevel presses the valve body of the check valve downwardly and steam can escape through the check valve. The pressure in the cooker is relieved, whilst the person using the cooker is warned simultaneously by the sound of the escaping steam not to unscrew the cap any farther. If the valve body has been raised only slightly owing to a slight superpressure in the cooker, eg at the onset of pressure build-up, an additional stop which projects into the clearance height prevents the cap from being rotated any farther.

The known valve assembly is expensive to manufacture, since it requires a valve housing and a valve body for the pressure relief means. These parts are expensive to manufacture and to assemble. The cap of the cooking valve is also expensive to produce owing to its asymmetrical shape, and the dimensions of the guide bevel as well as the region of reduced clearance height must be kept within a narrow tolerance range: the valve body must be pressed downwardly to open the valve on the one hand, although on the othe hand this must not be so far that the valve head closes the opening externally. Another drawback is that when the cap is rotated into the open position, the stop jams the head of the valve body and this cannot return to its original position, even when the cooker is not under pressure, until the cap has been turned back somewhat. When the check valve functions as a safety valve, the valve disk cannot automatically turn back any longer due to the valve opening. The cap cannot be screwed off over the projecting valve body either. This makes it impossible to gain access to the valve body and return it to the normal position. Yet another disadvantage is that the valve body of the check valve can only be cleaned thoroughly--quite essential for proper sealing--if it has been snapped out of the valve disk. Since this is complicated and troublesome, such cleaning is frequently postponed or forgotten completely.

A valve assembly comprising a pressure relief means disposed adjacent to the cooking valve is also known from German utility model No. 7,624,730. The pressure relief means is designed as a safety valve in the form of a check valve. The cap of the cooking valve has indents on the periphery thereof. Both valves are spatially associated with one another such that the valve body can be raised adjacent to such an indent only when the cap is in certain positions. The check valve can be closed and pressure built up in the cooker only in this position. When the valve body is in the raised position, ie when pressure has built up in the cooker, the valve body in turn locks the cap of the cooking valve which cannot be rotated. Hence, the vent opening cannot be opened by adjusting the cap. This known valve assembly, which therefore does not correspond to the preamble of the present invention, is expensive to manufacture due to the design of the check valve. It is also difficult to clean, since the steam is dissipated to one side through a cavity in the cooking valve beneath the cap when the safety valve responds to excessive pressure. These cavities are difficult to reach, even after the cap has been removed. Furthermore, the valve body cannot be turned back into its original position until after the safety valve has responded and the excess pressure has been vented off. Only then can the cap be removed from the cooking valve.

The object of the present invention is to provide a valve assembly according to the preamble of the claim which is economical to manufacture, easy to clean and simple to operate in all modes of operation.

The construction of the closure body as a seal disposed on the cap makes it possible to design the vent opening in the form of a simple hole in the cover without any valve housing. Such a hole can be produced during one and the same operation as the hole for the cooking valve. It is easy to clean. The arrangement of the associated seal in the cap gives rise to a constructional design which is simple and easy to clean. This construction of the pressure relief means is made possible by the recognition that the vent opening need only be open to relieve the pressure. An open valve is unnecessary prior to a pressure build-up, since the air being heated up can escape by way of the conventional sealing rings between the pressure-cooker and the cover until the sealing ring abuts sealingly against the cover and cooker wall due to the build-up of pressure. In the pressure relief means in accordance with the invention, the co-operation of the seal and the vent opening permits steam to escape even when the cap is moved minimally towards the venting position. The pressure in the cooker decreases immediately. Moreover, the co-action of the venting opening and the seal generates a warning sound which warns the cook not to opening the cooking valve while the cooker is still under pressure. If there is no seal in the cap, no pressure will build up in the cooker at all.

The seal can advantageously consist of a material which is so resilient that it sealingly closes the vent opening at normal cooking pressure and permits pressure to be vented should it become eccessive. The pressure relief means thus functions as a safety valve as well.

The annular seal advantageously has an internal diameter which is smaller than the external diameter of the cap section it surrounds. The annular seal is thus seated in the cap region in such a way that it can be neither twisted nor lost. Dirt cannot readily collect between the cap and the annular seal so that the seal does not have to be removed every time the cooker is cleaned.

FIG. 1 indicates the cover 1 of a pressure-cooker. A valve housing 2 is firmly riveted into place in the cover 1. It includes a valve seat 2a against which a valve body 3 is urged by a valve spring 4. This valve spring 4 presses against the inner side of a cap 5 overlying the entire valve assembly and designed as a cap or acorn nut. A pressure indicator 6 is displaceably mounted in the valve body 3. It is pre-biased by a pressure indicator spring 7 which presses against the valve body on the one hand and, on the other hand, against the inside of the cap 5. The cap 5 is adapted to be screwed on to the valve housing by means of a thread 8, thereby determining the tension of the valve and pressure indicator springs.

The cover 1 has a hole 10 in spaced relation from the valve axis and is located between the internal and external diameters of the annular seal. It serves as a vent opening and is closed by the annular seal 9 during cooking.

The afore-described valve assembly functions as follows during cooking: the cap 5 is screwed down to the stop with the inscription "cooking" adjacent to the arrow 12. The valve spring as well as the pressure indicator spring are both pre-biased in this position. The annular seal 9 closes the hole 10. Steam pressure can now build up in the cooker in the known manner once the warm air has escaped between the cooker and the cover as mentioned above. The cooking pressure is chosen by regulating the supply of heat in response to the position of the pressure indicator 6. At the conclusion of cooking, the cap 5 is turned half a turn to the "venting" position. This causes the annular seal to release the hole 10, the steam can escape and the pressure is relieved. The venting is continuous and dependent on the speed of rotation.

If the pressure indicator is not observed during cooking, i.e. if the supply of heat is not turned down at the proper time, thus causing the pressure in the cooker to become excessive, the steam can escape through the hole 10. This gives off a warning whistle and deforms the annular seal 9. Should the generated steam still be excessively high, the valve body 3 is lifted off its seat 2a.

to be paid before shipment. or L/C for normal orderQ: Can I get samples from your factory?A: Yes, Samples can be provided.Q: What is your advantages?A: As a professional brass valve and brass fitting manufacturer,we have most advantages:

We tried three Magefesa models and Practika is our favorite. It has the heft of the premium cookers without the flashy design (or price) – but the savings is paid in quirks.  Once the cook figures out the Practika’s naughty gasket and tricky valve this cooker gets the job done consistently, reliably and predictably.

The Magefesa Practika Plus gets our top rating in this category because its features are not just comparable to premium pressure cookers.  The extra-thick aluminum disk in the base and fill lines, which are often missing on mid-range pressure cookers,  make sauteing a breeze and saves the cook from having to eye-ball and guess whether they’ve reached the maximum fill.

Pressure Selector – Choose from four settings with a twist of a knob: High pressure 15psi (100kpa), low pressure 9psi (60kpa), pressure release and no pressure (to remove the valve).

Fill Lines – Capacity marks inside the pot indicate, 1/2 full (maximum for cooking grains, beans and other foamy foods) and MAX (maximum for regular pressure cooking).

Thick Aluminum Disk – Practika’s 3-ply base features an aluminum disk which is 4mm thick -thicker than most economy pressure cookers.  For comparison, the premium WMF Perfect plus aluminum disk is 4.5mm thick)

The Magefesa Practika Plus has the standard set of redundant safety features, comparable to its peers.  An oddly-placed lid vent gives this cooker’s score a small ding.

Self-locking Handle– When the red pressure indicator begins to rise, it will automatically lock the pressure cooker  closed preventing the cook from opening it accidentally while the contents are under pressure.

Correct Placement Nub – A small metal  projection inside the lid, that pushes the gasket slightly out of alignment to stop the cooker from building pressure if the lid is just rested on top of the cooker or the lid is not properly locked.

Primary over-pressure release valve – Integrated in the pressure selector, it activates to release pressure if internal pressure exceeds 18 PSI it begins to release excess pressure.

Secondary safety valve– Integrated in the red pressure signal activates if the primary should be obstructed or not working properly to release pressure.

Gasket vent– The safety vent is a cut-out on the lid and comes into action in case any of the previous safety measures were to fail. The gasket will buckle and allow pressure (and some of the contents of the pressure cooker) out of the pressure cooker. The cook should always point this cut-out in the rim awayfrom him while operating the pressure cooker. Unfortunately, the vent of this cooker is on the left, while the pressure release is exhausted to the right. This means that this vent must point towards the cook in order for the pressure release to point towards the cooking back splash.

Overall  the Magefesa Practika Plus’s performance was above average.  It’s great that the cook can select pressure by twisting a knob but it’s tricky to turn and we really didn’t like how the pressure indicator behaves or how difficult it is to see.  A few more kinks, such as gasket placement and multi-language lid, may cause new cooks to stumble.  On the plus side, releasing pressure is a snap and we found an undocumented way to regulate the speed of the pressure release, too!

Selecting pressure is tricky with this pressure cooker because the cook must push down on the selector slightly while simultaneously twisting it – like the safety-cap of a medicine bottle.  Push and twist the knob to I for low pressure (9psi) and II for high pressure (15psi), the little cloud to release pressure and the circle with a slash going through it to remove the valve for cleaning. The selections are not easy to see – you need some very bright lights to see the raised black lettering on the black handle.

The pressure indicator is a red metallic rod in the lid/handle casing. We dinged this cooker’s score in this category twice because the indicator is difficult to see and it’s tricky to ascertain when full pressure has actually been attained.  The cook needs to lean over the cooker and look inside the hole to see it when it has no pressure.  When it does rise, it does so to just under the casing. So, again the cook would have to lean over and look at the lid to understand if the indicator is up or down but without any obvious reference point.

We don’t like how this pressure cooker indicates reaching full pressure for the same reason we didn’t like how the Fagor Futuro did it.  That’s because the indicator rises when the cooker is reaching pressure, not when it has reached the full pressure chosen by the selector.  This can confuse beginners into turning down the heat before the cooker has actually reached the selected pressure – making the cooker appear as if it cannot maintain pressure. In fact, a popular American cooking magazine wrongfully declared this cooker troublesome and unable to reach or maintain pressure in its reviews and we suspect the signal’s tricky function was the cause.

It’s worth noting that Magefesa’s newer pressure cooker Model, Rapid III, has fixed this issue by using two pressure indicators.  However, we chose not to review the Rapid III because of some minor design flaws that only affect is usability – of which we informed the manufacturer.

Tricky Gasket PlacementAll of the Magefesa pressure cooker models we’ve seen so far tend to have gaskets that do not automagically go in the correct position.  Before starting to cook with the Magefesa Practika, the cook needs to ensure that the gasket is under the gasket guides in the lip of the lid and passing in front the correct placement nub (as shown). Trying to close the lid of any Magafesa pressure cooker with a gasket that is out of alignment can be both frustrating to the cook and damaging to the gasket!

The only big surprise, both for us and the manufacturer, was that we measured the cooker cooking at an average of 118°C and not the expected 120°C (about 15psi) as stated in their cooker’s specifications.  Also, Magefesa Practika Plus’ evaporation rate was just a tad bit higher than comparable pressure cookers 4.5% (compared to 3.5% evaporation rate from Fagor Futuro) but required much less heat to maintain pressure knob position 1.8 compared to 2.75.

Releasing pressure on the Magefesa Practika Plus is easy. Just twist the selector knob to the release position and go do something else.  It was designed assuming the cook would turn the handle of the cooker to the right in order for the steam to spray towards the backsplash of the cooktop (unlike other models where the manufacturer assumes the cooker will be used with the handlepointing towards the cook).

While testing and using this pressure cooker we found an undocumented way to regulate the speed of the pressure release- useful when releasing pressure for foamy foods or trying to accelerate a natural release. While most selector-type cookers, like this one, include a selection to release pressure usually the only way to release it is full throddle.  This is where the aforementioned tricky medicine bottle safety-cap style operation of the selector becomes an advantage.   Once on the selector is moved to the “pressure release” position, the selector can be pushed down all the way stop the pressure release completely or slowly lifted to the cook’s preference for a slow, medium or full speed pressure pressure release.

Lost in translationWe don’t ding for this but it’s worth noting that the lid is unnecessarily written in two languages.  The arrows on either side of the red button should indicate “Open” and “Close.” Instead the Magefesa Practika shows the letter “C” for closed and “A” to open (Cerrado and Abierto in Spanish). Then, around the pressure signal and on the handle is written “Gebrauchsanweisung Beachten” which just means “Read Instructions before use” but this time in German. It struck us as odd because most manufacturers use symbols that can be interpreted internationally such as a picture of an instruction book and icons of either little locks or pots to indicate which way the cooker handle or lock needs to move to open or close.

We were disappointed to discover this pressure cooker requires hand- washing only for all parts. Because of the lack of convenience, we gave the cooker two dings in this area.

Depending on the retailer, some Magefesa Practika pressure cookers come with a trivet and steamer basket.  We did not receive a set so we cannot comment on their quality or practicality.

Available Sizes: 3 to 7 liters (European manufacturers sometimes round these European liter sizes to quarts so if you purchase a 6 “quart” pressure cooker it’s the European 6L which is really 6.34 quarts)

With a little extra attention to the  correct placement of the gasket  and understanding of how this cooker signals it has reached pressure,  this cooker never failed to reach or maintain pressure for us – and  not just during our tests,  we used this cooker at least weekly for several months before and after testing as well.

This pressure cooker does require a little bit of attention, and the familiarizing process is a bit longer compared to its peers but once once all its little intricacies are understood it will become a dependable member of your kitchen arsenal.

In the interest of full disclosure, we would like to note that: The pressure cooker was sent to Hip Pressure Cooking by the manufacturer at no cost. Our relationship with the manufacturer, or lack thereof, does not affect the outcome of the review.

There is no international pressure cooker  organization that sets a global standard.  Pressure cooker UL Rating, which is an American Appliance Testing standard, only states that a domestic pressure cooker “operate at a nominal pressure of 15 psi (103 kPa) or less.” While in Europe the CE rating, the equivalent to the American certification, state that a “simple pressure vessel” can be above .5 bar (7.2 psi) and below 50 bar (720 PSI) . American manufactured pressure cookers adhere to a standard for pressure canners set by USDA in 1917 – 15 psi.

While some European pressure cookers are sold world-wide many of these manufacturers make a separate model specifically for the American market that reaches 15 psi.  Some European manufacturers are switching to a single model distributed world-wide that reaches 15 psi. At the writing of this article,  American pressure cooker manufacturers only sell their pressure cookers in the United States.

All recipes and cooking time charts on this website are written to accommodate both “standard” and “non-standard” pressure cookers.  When necessary,  times are written in a range – standard pressure cookers should use the shorter cooking time (13 minutes) and non-standard pressure cookers the longer (20 minutes).

This comes down to the difference in measuring systems between the United States (imperial) and the rest of the world (metric).  Pressure in the rest of the world is measured  inkilopascals (kPa) and bars while the U.S.it is measured with pounds per square inch (psi).

European manufactured pressure cookers are designed to cook at 1 bar or 100 kpa (metric pressure measurements) and that translates to 14.5 psi (this is rounded up to 15 psi) but American manufactured pressure cookers are designed to reach a full 15 psi (see below, for information on electric pressure cookers).

The rise in pressure inside the pressure cooker directly correlates to the rise in boiling point – the maximum cooking temperature that can be achieved at a given pressure.

The pressure cooker adds pressure above the current atmospheric pressure. Since there is a pressure difference in the atmosphere between one altitude and another, the pressure cooker’s pressure will vary accordingly.

Moving up in the atmosphere, or going to higher altitude, the atmospheric pressure decreases.  So in Denver Colorado (about 5,000 feet) the atmospheric pressure averages only 12.2 psi- add 15 psi of pressure generated by the cooker and there the food is cooking at just 27.2 psi of absolute pressure -almost 3 psi less pressure than pressure cooking at sea level!

The same 15 psi pressure cooker will cook 15 psi in San Francisco, California (sea level) but only 12.5 psi in Denver, Colorado (5,000 feet).  Now, “standard pressure cooker” has become “non-standard” in Denver.  This means that the recipes will need the same timing adjustments used  for non-standard pressure cookers (see pie chart, above).

Increase pressure cooking time by 5% for every 1000 ft above 2000 ft elevation (see table, below). Multiply the recommended cooking time by the number on the table. The result will likely be a decimal value just round that up to the next minute.above...increase by..or multiply by..

The transformation from a Renaissance “bone digester” invented by French scientist Denis Papin (in 1689) to pressure canners (1905)  and finally to the pressure cooker we know today began in 1926. The Home Exhibition in Paris introduced the first model for home use. The pressure cooker made it out of Europe and into the United States via the 1939 New York Fair where the National Pressure Cooker Company launched the first U.S. model.

Aluminum pressure cookers took off in the U.S. and many companies began producing them. Then, America’s involvement in WWII halted the production of pressure cookers and their factories were dedicated to producing munitions for the overseas war.

Once the war ended, European and American pressure cooker manufacturers began to develop and produce pressure cookers independently from each other. While in America unscrupulous factories made and sold sub-standard pressure cookers – that eventually went on to mar the cooker’s reputation and halt innovation- European manufactures continued to develop, perfect and innovate their designs adding multiple redundant safety mechanisms, selectable pressure levels and more features.

The 90’s started the trickle of European manufactured pressure cookers, and their features into America. It’s also when the patent for the first electric pressure cooker was filed by Chinese scientist, Mr. Yong Guang Wang.  The electric pressure cooker was developed independently from stovetop pressure cookers in that they were based on the ever-popular electric rice cookers (hence the resemblance) and are manufactured in a range of pressures – depending on the manufacturer or design team.

At the time of the writing of this article, most electric pressure cookers reach 15 psi but they do not cook at 15 psi.  As illustrated by the graphic below – electric pressure cookers reach 15 psi briefly during the warming process.

Electric pressure cookers build pressure up to 15 psi but then maintain a lower pressure during the cooking.  In the  graph below the “operating pressure” is 11.6 even though the cooker reaches 15 psi while it’s building pressure. “Operating Pressure” is the true pressure at which an electric pressure cooker cooks.

Valve Release Pressure – the pressure at which the main regulating valve releases pressure (2 to 4 psi more than the operating pressure depending on the manufacturer).

Electric pressure cookers will have the “valve release pressure” written in very small text on the underside of the pressure release valve either on the plastic housing, or the metal part of the valve.