ICS 17.100  
N 11  
 
 
National Standards of the People’s Republic of China  
 
National standard GB  xxxx -xxxx  
 
 
 
 
 
 
 
 
 
 
General safety regulations for elastic pressure 
gauge  
 
 
 
(Draft for approval)  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
xxxx -xxxx publication                              xxxx -xxxx implemented  
 
 
General Administration of Quality Supervision, Inspection and Quarantine of the 
People’s Republic of China publication  PREFACE  
 
Part 2.4 of this standard is recommended, the rest are mandatory.  
 
Appendix A of this standard for t he informative purposes.  
 
This standard is put forward by the China Federation of Machinery Industry . 
 
The standard comes from the Industrial Process Measurement and. Control of 
Standardization Administration of China  (SAC/TC124).  
 
This standard has been d rafted by Xi'an Industrial Automation Instrumentation.  
 
The following units participated in the drafting of this standard: Hongqi (Eternal 
happiness) Instrument Co. Ltd, Leierda Instrument Co. Ltd, Ningbo Longxing 
Welding Technology Co. Ltd, Anhui Land Gro up Co. Ltd, Zhejiang Precision 
Instrumentation Co. Ltd, and Ningbo Jiangbei Xingda Welding pressure reducer 
factory.  
 
The main drafters of this standard are Luo Juan, Liu Yaowu, Hu Yuanxing, Wang 
Fanggao.  
 
This is the first edition of this standard.   
GB ×  × × × -× × × ×  
 
 
General safety regulations for elastic pressure 
gauge  
 
 
1 Scope  
The standard stipulates the specifications for a safe elastic pressure gauge, 
including all safety requirements, testing methods and evaluation guidelines.  
 
This standard appl ies to the spring tube (including the helical spring tube, coil 
spring tube and the C -tube), diaphragm, sylphon and bellows pressure gauge 
pointer (hereinafter referred to as instruments).  
 
2 Requirements  
 
2.1 Breakage  
The gauge should withstand the settin gs outlined in Table 1 below without 
leakage.  
Table 1  
Measurement 
limit (MPa)  Alternating load 
frequency  Alternating 
frequency rate  Alternating 
amplitude  
2.5 100000  
>2.5  60 50000  
>60  160  25000  60 times / min ± 5 
times / min  
or 30 times / min 
± 5 times / min  Limit values:  
 (30 ± 5)%  (60 ± 5)%  
(the total range of 
alternating 
measurement should be 
no less than 30% of 
upper limit)  
 
2.2 Excessiv e pressure  
The gauge should withstand the load values outlined in Table 2 for a period of 15 
minutes without leakage.  
Table 2  
Scale Value  Static load values  
10 1.5 times that of the maximum value  
>10  60 1.3 times that of the maximum value  
>60  160  1.2 times that of the maximum value  
Note: The corresponding standard has no pressure override function for the 
product, but it does not make the requirements.  
 
2.3 Pressure relief function  
The gauge has the pressure relief function, when the elastic com ponent ruptures, 
the pressure accumulated within the case should be released, without causing 
the glass to break  
  
GB × × × × -× × × ×  
 
2.4 Safety requirements  
Please see the guidelines provided in Appendix A for information about safe use 
of the gauge.  
 
 
 
3 Testing  
 
3.1 Test conditions  
The ambient temperature for testing should be (20 ± 5) ° C.  
 
3.2 Testing equipment  
a) You should use sinusoidal alternating equipment.  
b) You should comply with the requirements of Table 2 when testing excessive 
pressure. Th e test should be conducted behind a protective device to protect the 
safety of testing personnel.  
c) Where the device is liable to succumb to instantaneous pressure release, the 
device should have a protective cover.  
 
3.3 Sampling  
Four pressure gauges are selected at random fro m an original group that must 
contain  no fewer than 20 devices.  
 
3.4 Testing methods  
 
3.4.1 Test sequence and duration of interval  
The test requirements for breakage from excessive pressure do not need to be 
conduc ted in any particu lar order, but the time interval between the two tests 
should be no less than 4 hours. The final test should be th e test  of the pressure 
release function.  
 
3.4.2 Breakage test  
Install the devices in the alternating load test device, according to the provis ions 
of the parameters specified in Part 2.1.  
 
3.4.3 Excessive pressure Test  
Install the devices in the excessive pressure test stand, set the gauge to the 
maximum limit, maintain pressure for 12 hours, then follow the parameters 
specified in Part 2.2.   
GB × × × × -× × × ×  
 
 
3.4.4 Pressure relief function test  
Install the devices in the instantaneous pressure release device, so that 
accumulation of gas energy E = pV, and then suddenly vent the gas from inside 
the case of the gauge.  
 
p    is the maximum value of gauge. If this value is less than 6MPa, then use 
4MPa. If the value is greater than 10MPa, then use 10MPa.  
 
V   is the volume approximation for the pipes and fittings of the internal gas 
spring tube.  
 
3.5 Evaluation guidelines  
If any one of the four randomly selected gauges fails to meet the standards of 2.1, 
2.2 or 2.3, then the item fails the safety test. Only those items for which every 
randomly selected gauge passes every test will be recorded as having passed the 
safety test.   
 
 
Appendix A  
(Information appendix)  
Safety guidelines  
 
A.1 for the protection of testing personnel, we recommend users to choose the 
gauge with a pressure relief function.  
 
A.2 Certain factors should be taken into considera tion, including the pressure on 
the gauge during the welding process, the impact of solder; the effects of 
temperature and the impacts of intensity and aggressive corrosion.  
 
A.3 If pressure gauges are filled with glycerol or silicone oil, these items shou ld 
not be used in highly oxidised environments, since the potential chemical 
reaction could cause an explosion.  
 
A.4 It is recommended that you install a limit restrictor between the elastic 
components and the pressure connection, as this can help control the escaping 
gas, and thus reduce risk.  
 
A.5 Once pressure tubing has been used, do not then use it for o ther purposes. If 
you must re -use it , you should consider the chemical compatibility as well as 
possible  breakage and corrosion.  
 
A.6 When the workin g pressure medium is corroded, you should consult with the 
manufacturers, choosing suitable elastic component materials and joints.