YY/T 1522-2017Flow-metering devices for connection to terminal units of medical gas pipeline systems (English PDF)

1.1 Scope of application

This standard applies to:

--- at the end of the medical gas pipeline system, connected or disconnected by the operator directly or through a flexible connection assembly, for adjustment, a flow measuring device for measuring flow rate and transporting medical gas;

--- A flow measuring device that is connected and disconnected by an operator at a gas-specific connection point of a device (eg, a pressure regulator).

1.2 Gases covered

This standard applies to:

1) Flow measuring device for the following medical gases.

---oxygen;

--- nitrous oxide (laughing gas);

---medical air;

---carbon dioxide;

--- Oxygen/nitrous oxide (laughing gas) mixture [50%/50% (volume fraction)];

--- A specific mixture of the above gases.

2) Flow measuring device for the following gases.

---Oxygen-enriched air;

---;

--- Helium.

3.1 DISS connector

Diameter limit safety system connector diameterindexsafetysystemconnector A set of inner and outer joint assemblies of different diameters that match each specific gas or facility to maintain gas specificity.

3.2 Flow meter flowgauge

Note. This flow meter does not measure flow. It indicates flow by measuring the upstream pressure of a fixed orifice.

3.4 Flow measuring device

a) a flow meter with a flow control valve;

b) flow meter, fixed orifice with flow control valve;

c) One or more fixed orifices with flow selection mechanism.

Note. Typical examples of flow measurement systems and devices are given in Figure B.1 and Figure B.2.

3.5 Gas-specific

Features to prevent cross-connections, allowing design to be used with only one gas or only vacuum.

3.7 Hose insert body

The part that is inserted into the lumen of the hose and fastened to the fitting on the hose.

3.9 Medical gas pipeline system

Central supply system with control equipment, including piping systems and terminals providing medical gas or vacuum, or any other A device with a permanent piping system, but a medical source with a pressure regulator.

3.10 Medical gas supply system

a) a medical gas piping system, or

b) Non-permanent piping systems, but with a device for a medical gas supply with a pressure regulator.

3.11 NIST connector

Non-interchangeable threaded joint non-interchangeablescrew-threadedconnector a set of outer and inner joints of different diameters and having left-hand or right-handed threads, respectively associated with mating joints of specific gases Connect to maintain the specificity of the gas.

3.13 Rated intake pressure

The flow measuring device is designed to operate with maximum intake pressure.

3.14 Single fault condition

There is only one safety hazard in the equipment that fails, or only one external abnormal condition.

3.15 Socket

The pluggable part of the terminal, which can be either a part of the terminal as a whole or a terminal of the terminal through a dedicated gas interface on. This section includes a dedicated gas connection.

3.16 Terminal

The output port assembly of the medical gas supply system (in the case of a vacuum) is connected and disconnected by the operator.

5.1 Security

The flow measuring device shall be in the normal state and single fault when transported, stored, installed, used and maintained according to the manufacturer's instructions.

In this state, there is no risk of higher than YY/T 0316 risk management program acceptance levels, and there is no risk associated with the intended application.

5.2 Alternative equipment

The material or structure used is different from this section (except for the size and distribution of DISS and NIST joints and inserts as inlet joints)

The flow measuring devices and components or components thereof, if they can be proved to be equivalent in safety, should be recognized (eg risk has been Lowering to an acceptable level can be considered as meeting the requirement) unless the opposite objective evidence is available.

Note 1. Objective evidence may be obtained during post-marketing surveillance.

Evidence of equivalent security levels should be provided by the manufacturer upon request.

Note 2. Risk management refers to YY/T 0316 and the international standards being developed by ISO /TC210.

5.3 Materials

5.3.1* In the temperature range specified in 5.3.3, materials in contact with the medical gases listed in 1.2 shall have resistance under normal conditions of use.

Corrosive, and compatible with oxygen, other medical gases and their mixtures.

Note 1. Corrosion resistance includes resistance to humidity and surrounding materials.

Note 2. Compatibility with oxygen includes flammability and flammability. Materials that burn in air will burn violently in pure oxygen. Many do not burn in the air The material will also burn in pure oxygen, especially under certain pressure. Similarly, materials that can be ignited in air cost less in oxygen.

The amount can be ignited. When such high pressure oxygen is quickly input into an initially low pressure system, many of these materials are subject to friction or insulation with the valve seat. Compressed and ignited.

Note 3. YY/T 0882 provides information on the selection of metals and non-metals as well as other information on the oxygen compatibility of the equipment.

5.3.2* For flow measuring devices applied to all gases, non-metallic parts in contact with gases, including sealing materials and lubricants (if Use), its auto-ignition temperature should not be lower than 160 °C.

Evidence that meets this requirement should be provided by the manufacturer on demand.

The auto-ignition temperature should be determined in accordance with ISO 11114-3.

Note. The maximum operating temperature of the test material should be 100 ° C lower than the auto-ignition temperature at the corresponding oxygen pressure. Safety margin is necessary because of operating temperature Unexpected growth, auto-ignition temperature is not a constant value. The value of the auto-ignition temperature always depends on the test method used, and the test method may Not all possible operating conditions are simulated exactly.

5.3.3 In the temperature range of -20 ° C ~ 60 ° C, the flow measuring device and its components should meet the requirements of 5.4 (except 5.4.6.3, 5.4.7.3 and 5.4.8.2).

5.3.4 When the transported and stored packaging is opened, the flow measuring device shall meet the requirements of 5.4 under the environmental conditions specified by the manufacturer.

5.3.5 Springs, highly tensioned parts and parts that are subject to wear and contact with gases shall not be plated.

Note. The coating may fall off.

5.3.6 Evidence that meets the requirements of 5.3.1~5.3.5 shall be provided by the manufacturer upon request.

5.4 Design requirements

5.4.6 Requirements for flow measuring devices containing flow meters with flow control valves

5.4.7 Requirements for flow measuring devices containing flow meters, fixed orifices and flow control valves

5.4.8 Requirements for flow measuring devices with one or more fixed orifices and flow selection mechanisms

5.4.1 Gas input port

5.4.1.1 Entrance

The gas inlet should be one of the following.

a) an insert that conforms to YY 0801.1 and is permanently attached to the flow measuring device [see Figure B.2a)];

b) a nut and mastoid connection that meets the DISS or NIST requirements of YY/T 0799 and is permanently attached to the flow measuring device Head [see Figure B.2b)];

c) use an insert conforming to YY 0801.1 as the inlet joint and a flow measuring device as the outlet joint Low pressure hose assembled by YY/T 0799 [see Figure B.2c)];

d) Use a nut and mast joint that meets DISS or NIST specifications in YY/T 0799 as the inlet fitting and use a flow rate The measuring device acts as an outlet joint for the low pressure hose assembled according to YY/T 0799 [see Figure B.2d)].

5.4.1.2 Filtering

The gas inlet should be equipped with a filter and the following requirements should be met.

a) replaceable;

b) There are small holes or equivalent filters of no more than 100 µm.

The manufacturer shall provide evidence of compliance with the requirements as required.

5.4.2 Air outlet connector

The air outlet connector should be one of the following.

a) a fixed mastoid joint in accordance with EN 13544-2;

b) threaded joints in accordance with EN 13544-2;

c) An exclusive accessory that can be fitted with or without a hose. Compliance is checked by visual inspection.

5.4.3* Mechanical strength The flow measuring device shall be in accordance with the pressures of 1000 kPa for 5 min and shall comply with 5.4.4, 5.4.6.3, 5.4.7.3 and 5.4.8.2. Claim. The mechanical strength test is given in 6.2.

5.4.4 Leakage

After the mechanical strength and accuracy test, when the flow control valve is closed with a torque of 0.4 N·m (or with multiple fixed orifices)

The flow measuring device is set to zero) and the total internal leakage should not exceed 0.3 mL/min (corresponding to 0.0303 kPa·L/min) under P1.

After mechanical strength and accuracy testing, the total external leakage (to the atmosphere) should not exceed 0.5 mL/min under P1 (equivalent to 0.0506 kPa·L/min). The leak test is given in 6.3.

5.4.5 Connection to the rail system

If the flow measuring device fitted with a gas inlet complying with 5.4.1.1c) or d) is designed by the manufacturer to comply with ISO 19054 If the rail system is supported, then it should be equipped with one of the following devices in accordance with ISO 19054.

---rail clamp;

--- Equipment floor;

--- Equipment floor pin.

5.4.6.1 Scales and indications

The flow meter should be used in liters per minute (L/min) or in milliliters per minute (mL/min) for flow rates equal to or less than 1 L/min. For the unit.

The flow meter indication should be visible at all flows and contain zero flow. Compliance is checked by visual inspection.

5.4.6.2 Readability

Under the illumination of 215lx, for the visual acuity of 1.0 (corrected if necessary), the operator of the flowmeter 1m should indicate the value of the flowmeter. It is clear and easy to recognize.

5.4.6.3 Flow accuracy

When the gas is directed to the ambient atmosphere and corrected to the reference conditions (see 6.1.3), for any flow with a maximum flow greater than 1 L/min The flow accuracy of 10%~100% of the full scale should be within ±10% or ±0.5L/min of the indicated value, whichever is greater.

When the gas is directed to the ambient atmosphere and corrected to the reference conditions (see 6.1.3), for any one of the maximum flows equal to or less than 1 L/min Flowmeter, flow accuracy should be within ±10% of full scale.

When the gas is directed to the ambient atmosphere, the accuracy test shall include the entire range of inlet pressures specified by the manufacturer. This test should be in mechanical strength After the test is completed.

The manufacturer shall provide evidence of compliance with the requirements as required.

In order to improve accuracy and reduce the risk of electrostatic discharge, it is recommended to provide a method of minimizing the electrostatic charge inside, outside and outside the flow tube.

5.4.6.4 Flow control valve Note.

The flow control valve can be located downstream or upstream of the flow meter [see Figure B.1a) and B.1b)]. In different supply pressures and outlet resistance The position at which the flow control valve is installed affects the flow measurement accuracy.

5.4.6.4.1 The flow control knob and valve stem should be well fixed and can not be removed without tools.

Try not to use the tool to remove the knob and stem to verify compliance.

5.4.6.4.2* The flow control valve shall be designed to increase flow when rotated counterclockwise. Compliance is checked by visual inspection.

5.4.7.1 Scale

5.4.7.1.1 The maximum scale value of the flow meter shall be at least 33% higher than the maximum flow specified by the manufacturer.

5.4.7.1.2 The flow meter shall be marked in increments per minute (L/min). Visual inspection should be performed to verify compliance.

5.4.7.2 Readability

Under the illumination of 215lx, for the visual acuity of 1.0 (corrected if necessary), the operator of the flowmeter 1m should indicate the value of the flowmeter. It is clear and easy to recognize.

5.4.7.3 Flow accuracy

When the gas is discharged to the ambient atmosphere and corrected to the reference conditions (see 6.1.3), on the scale of 10%~100% of the full scale of the flow meter The flow accuracy should be within ±10% or ±0.5L/min of the indicated value, whichever is greater.

When the gas is vented to the ambient atmosphere, the accuracy test shall include the entire range of inlet pressures specified by the manufacturer. This test should be strong in mechanical After the test is completed.

The manufacturer shall provide evidence of compliance with the requirements as required.

5.4.7.4 Flow control valve Note.

The flow control valve can be located downstream or upstream of the flow meter. In the case of different supply and outlet resistances, the position of the installation will affect the measurement Precision.

5.4.7.4.1 The flow control knob and stem should be well fixed and must not be removed without tools.

Try not to use the tool to remove the knob and stem to verify compliance.

5.4.7.4.2* The flow control valve shall be designed to increase the flow rate in the counterclockwise direction. Compliance is checked by visual inspection.

5.4.7.5 Flow Meter

5.4.7.5.1 If a Bourdon flow meter is used, it shall comply with EN 837-1 (except for the minimum nominal size) or

GB/T 1226-2010, and shall comply with the requirements of 5.4.7.1, 5.4.7.2, 5.4.7.5.2 and 5.4.7.5.3. 5.4.7.1, 5.4.7.2, 5.4.7.5.2 The requirements of 5.4.7.5.3 and 5.4.7.5.5 also apply to other types of flow meters.

5.4.7.5.2 If the fitting of the flow meter is threaded, the thread shall comply with EN 837-1 or GB/T 1226-2010.

5.4.7.5.3 The flow meter shall be of class 2.5 or higher specified in EN 837-1 or GB/T 1226-2010.

5.4.7.5.4 The flow meter shall be calibrated to the fixed orifice as intended.

5.4.7.5.5 The manufacturer shall provide evidence in accordance with the requirements of 5.4.7.5.1 to 5.4.7.5.4 as required.

5.4.8.1 Readability

Under the illumination of 215lx, for the visual acuity of 1.0 (corrected if necessary), the operator of the fixed orifice 1m, the fixed orifice The indication value should be clear and easy to recognize.

5.4.8.2 Flow accuracy

If the flow rate is greater than 1.5L/min, the actual flow rate should be within ±20% of the specified value.

If the flow rate is equal to or less than 1.5L/min, the actual flow rate shall be within ±30% of the specified value.

When the gas is vented to the ambient atmosphere, the accuracy test shall include the entire range of inlet pressures specified by the manufacturer. This should be measured in mechanical strength After the test.

The manufacturer shall provide evidence of compliance with the requirements as required.

5.4.8.3 Traffic Settings

5.4.8.3.1 If there are multiple holes, when the flow selection mechanism is from "closed" and from one position to another, it acts on the most The tangential force at a large radius should be no less than 5N and no higher than 50N.

The manufacturer shall provide evidence of compliance with the requirements as required.

5.4.8.3.2* The flow selection mechanism should automatically center at each flow set point and should minimize the possibility of being in a no-flow position (eg Between adjacent set points), unless it is a 0 flow set point. Compliance is checked by functional testing.

5.4.8.3.3* If a flow measuring device containing multiple fixed orifices can be placed between adjacent gears so that there is no flow at the outlet, Set a warning for this result on the device.

5.4.8.4 Removal of fixed orifices

The removal of the fixed orifice requires the use of tools.

Try removing the fixed orifice without using a tool and verify that it meets the requirements.

5.4.8.5* Traffic Selection Mechanism The flow selection mechanism should be well fixed and cannot be removed without tools.

Try to remove the traffic selection mechanism without using a tool to verify compliance.

If the flow selection mechanism is rotating, it should be designed to increase flow when rotated counterclockwise. Compliance is checked by visual inspection.

5.5 Assembly requirements

5.5.1* Cleaning Flow measuring devices in contact with medical gases during normal use shall comply with the cleaning requirements specified in YY/T 0882.

The manufacturer shall provide evidence of compliance with the requirements as required.

5.5.2* Lubricant If a lubricant is used, the lubricant should be capable of reacting with oxygen, other at a test pressure of 1000 kPa and within the temperature range specified in 5.3...