CN205303097U - Superconducting magnet's drain tap , superconducting magnet and magnetic resonance imaging equipment - Google Patents

Abstract

The utility model relates to a superconducting magnet's drain tap, superconducting magnet and magnetic resonance imaging equipment. Drain tap includes a first bursting diaphragm, a second bursting diaphragm and a buffer, and first bursting diaphragm and second bursting diaphragm cascade, and the buffer is located between first bursting diaphragm and the second bursting diaphragm, wherein, buffer pressure is greater than superconducting magnet's external pressure, and the rated pressure of first bursting diaphragm is greater than buffer pressure and superconducting magnet's external pressure poor simultaneously, and the rated pressure of second bursting diaphragm is greater than superconducting magnet's internal pressure and buffer pressure poor. Because superconducting magnet's drain tap introduces first bursting diaphragm and the buffer pressure between two bursting diaphragms means: even after considering the rated pressure's of first bursting diaphragm tolerance, its external pressure (cargo hold pressure) that still can bear the superconducting magnet that is not less than specified pressure, so second bursting diaphragm cracked possibility greatly reduced in the transportation.

Description

The drain tap of superconducting magnet, superconducting magnet and MR imaging apparatus

Technical field

This utility model relates to field of medical device, particularly the drain tap of a kind of superconducting magnet, superconducting magnet and MR imaging apparatus.

Background technology

In the superconducting magnet refrigeration system requiring over cooling superconducting magnets and realizing stationary magnetic field, superconducting magnet refrigeration system in nuclear magnetic resonance (MRI) equipment, superconducting magnet is generally placed in a cryogen vessel (cryogenvessel), cryogen vessel is placed on again an external vacuum intracavity, space between vacuum chamber and cryogen vessel is evacuated, and provides effective thermal insulation for cryogen vessel. Additionally, in order to reduce the radiant heat between vacuum chamber and cryogen vessel, sometimes also arrange a thermal radiation between vacuum chamber and cryogen vessel.

When freezing, by making the vaporization of seething with excitement of the liquid refrigerant (such as liquid helium) in cryogen vessel make superconducting magnet cool down predetermined temperature, i.e. operating temperature. But know from experience at superconducting magnetic in some cases and quench, such as when running into some dangerous situation and needing to drop, magnet quenching, electromagnetic energy is heat energy, magnet temperature is made to raise, and then a large amount of of liquid refrigerant (such as liquid helium) can be caused to volatilize, the pressure in container can be made in the short time sharply to raise. If the refrigerant gas of volatilization can not be discharged in time, pressure in container exceedes design pressure will cause the destruction of container, this is breakneck, therefore can be provided with the control pressurer system of cryogen vessel in existing superconducting magnet refrigeration system, including discharge duct and relief valve etc. Such as, for Stress control when quenching, it is usually provided with the discharge duct quenching valve and correspondence. It addition, in order to avoid the situation that cannot open exhaust passage when magnet quenching because quenching valve damage, a rupture disk bypass can be arranged, when quenching valve and cannot open so that this rupture disk breaks and opens exhaust passage. Additionally, in order to, under superconducting magnet operating temperature, the issuable pressure oscillation of cryogen vessel is controlled, this control pressurer system is also provided with a pressure-regulating valve, in order to the pressure in cryogen vessel is opened when exceeding setting threshold value. In one embodiment, above-mentioned valve, rupture disk bypass and the pressure-regulating valve of quenching can be connected with cryogen vessel by a service tower outer housing.

In addition, the magnetic resonance imaging system of air transport can be loaded in normal pressure cargo hold, described normal pressure cargo hold under high altitude condition can relative to 14.7psi (pound/square inch, poundspersquareinch) ground face amount stands the pressure drop of 10psi (pound/square inch, poundspersquareinch).This pressure drop is enough to rupture any bursting diaphragm being generally used on magnet thus causing that large quantity of air enters in helium closed system. Accordingly, it would be desirable to avoid bursting diaphragm to rupture under cargo hold pressure change condition, properly functioning when still making its excess pressure in helium closed system simultaneously.

Therefore, what the present invention was encountered is the technical problem about low specified bursting diaphragm; In existing design, the rated pressure of design pressure and bursting diaphragm is reached 1.8bar. The pressure differential of cargo hold is not a problem with this understanding, but this solution is specifically for being generally in 1bar or the low pressure explosion barrier film lower than 1bar. A kind of replacement scheme removes or replaces bursting diaphragm, but the program exists infringement security system or/and have the risk introduced air in helium closed system, and this can cause ice to block up at low temperatures potentially.

Utility model content

In view of this, this utility model proposes the drain tap of a kind of superconducting magnet on the one hand, including one first bursting diaphragm, one second bursting diaphragm and a buffer, described first bursting diaphragm and described second bursting diaphragm cascade, described buffer is between described first bursting diaphragm and described second bursting diaphragm, wherein, buffer pressure is more than the external pressure of described superconducting magnet, the rated pressure of described first bursting diaphragm is more than the difference of buffer pressure and the external pressure of described superconducting magnet simultaneously, the difference of the rated pressure of the described second bursting diaphragm internal pressure more than superconducting magnet and buffer pressure.

In one embodiment, described buffer includes Single port and a valve, and described valve is installed on described port, is used for regulating described buffer pressure.

The utility model proposes a kind of superconducting magnet, including drain tap as above.

The utility model proposes a kind of MR imaging apparatus, including superconducting magnet as above.

Can be seen that from such scheme, the drain tap of the superconducting magnet owing to the utility model proposes introduces the first bursting diaphragm and the buffer pressure between two bursting diaphragms means: even if after considering the tolerance of the rated pressure of the first bursting diaphragm, it still can bear the external pressure (cargo hold pressure) of the superconducting magnet being not less than specified pressure, and the probability that therefore the second bursting diaphragm ruptures in transportation is substantially reduced.

Accompanying drawing explanation

Following by of the present utility model preferred embodiment is described in detail with reference to the drawings, the person of ordinary skill in the art is more clear that of the present utility model above-mentioned and other feature and advantage, in accompanying drawing:

Fig. 1 is the principle schematic of the drain tap of superconducting magnet in this utility model embodiment.

Detailed description of the invention

For making the purpose of this utility model, technical scheme and advantage clearly, by the following examples this utility model is further described.

The principle of the drain tap according to superconducting magnet of the present utility model is in that to make former bursting diaphragm be held in place putting and not endangering safety, therefore comprises a new bursting diaphragm outside former bursting diaphragm according to the drain tap of superconducting magnet of the present utility model. The pressure retaining volume between two bursting diaphragms may be adjusted to guarantee that new bursting diaphragm will not rupture in high altitude condition, still allows for bursting diaphragm simultaneously and ruptures when overpressure events. Buffer has port and valve to check the sealing of buffer and to be used subsequently to fill the gas of convenient pressure, to obtain required pressure reduction.

Fig. 1 is the principle schematic of the drain tap of superconducting magnet in this utility model embodiment.As shown in Figure 1, drain tap 100 according to superconducting magnet of the present utility model, including one first bursting diaphragm 101, one second bursting diaphragm 102 and a buffer 103, described first bursting diaphragm 101 and described second bursting diaphragm 102 cascade, described buffer 103 is between described first bursting diaphragm 101 and described second bursting diaphragm 102, wherein, buffer pressure Pb is more than the external pressure Ph of described superconducting magnet, the rated pressure of the described first bursting diaphragm difference more than the external pressure Ph and buffer pressure P b of superconducting magnet, the rated pressure of the described second bursting diaphragm difference more than the internal pressure Pi and buffer pressure P b of superconducting magnet.

For example, if the rated pressure of the second bursting diaphragm is the internal pressure Pi=16psi of 13psi and superconducting magnet, then external pressure (cargo hold pressure) Ph in superconducting magnet when not using the first bursting diaphragm < is ruptured during 3psi by the second bursting diaphragm. After considering the tolerance of the 10% of rated pressure of the second bursting diaphragm, external pressure (cargo hold pressure) Ph of the difference of its internal pressure Pi with superconducting magnet just closely superconducting magnet, therefore the second bursting diaphragm probably ruptures in transportation. But, the buffer pressure introducing first bursting diaphragm of rated pressure 15psi and the 14.7psi between two bursting diaphragms means: even if after considering the tolerance of 10% of the rated pressure of the first bursting diaphragm, it can bear external pressure (cargo hold pressure) Ph of the superconducting magnet being not less than 14.7-13.5=1.2psi, and the probability that therefore the second bursting diaphragm ruptures in transportation is substantially reduced.

The foregoing is only preferred embodiment of the present utility model; not in order to limit this utility model; all within spirit of the present utility model and principle, any amendment of making, equivalent replacement, improvement etc., should be included within protection domain of the present utility model.

Claims (4)

1. the drain tap of a superconducting magnet, it is characterized in that, including one first bursting diaphragm, one second bursting diaphragm and a buffer, described first bursting diaphragm and described second bursting diaphragm cascade, described buffer is between described first bursting diaphragm and described second bursting diaphragm, wherein, buffer pressure is more than the external pressure of described superconducting magnet, the rated pressure of described first bursting diaphragm is more than the difference of buffer pressure and the external pressure of described superconducting magnet simultaneously, the difference of the rated pressure of the described second bursting diaphragm internal pressure more than superconducting magnet and buffer pressure.

2. the drain tap of superconducting magnet as claimed in claim 1, it is characterised in that described buffer includes Single port and a valve, and described valve is installed on described port, is used for regulating described buffer pressure.

3. a superconducting magnet, it is characterised in that include drain tap as claimed in claim 1 or 2.

4. a MR imaging apparatus, it is characterised in that include superconducting magnet as claimed in claim 3.