Industrial production valve installation application maintenance general requirements of self-regulated temperature valve application status
Actuating valve action method, self – actuating and external force. Self-reliant refers to the internal structure of the valve formed by the change of material working pressure, temperature and other forces to drive the valve core various moving components; External force driving refers to the use of external force to drive various moving components of the valve core, including manual, electric, pneumatic, hydraulic control valve, electromagnetic induction drive and these collaborative driving methods. Invalid valve includes invalid sealing, invalid posture, function failure, etc. Invalid tightness includes exposure and air leakage. Invalid posture includes drive failure, seat stuck, spool dead, etc. Function failure according to the valve type is different…
Category 1
This standard describes the general requirements for installation, application and maintenance of industrial metal valves.
This specification applies to globe valves, globe valves, relief valves, gate valves, disc valves, pneumatic butterfly valves, plug valves, check valves, valves, pressure regulating valves, steam traps, regulating valves and other valves.
2 Normative reference documents
The provisions in the following documents become the relevant provisions of this Specification according to the introduction of this specification. If a document is dated, each subsequent change (without erratum) or revision is not suitable for this specification. However, if a document is not dated, the version number of the version number shall be applicable to the specification to encourage various scientific researches to reach consensus on whether the document information can be used.
GB/T 13927 Pressure test for industrial production valves (GB/T 13927 2008,ISO/DIS 5208:2007,MOD)
JB/T 9092 valve test and experiment
3 Definition of Terms
The following terms and definitions apply to this specification.
Connection mode tonnect}on mode
Valve tip and pipe or equipment access form, including looper flange, flange connection, threaded connection, groove connection, etc.
driving method driving micans
Actuating valve action method, self – actuating and external force. Self-reliant refers to the internal structure of the valve formed by the change of material working pressure, temperature and other forces to drive the valve core various moving components; External force driving refers to the use of external force to drive various moving components of the valve core, including manual, electric, pneumatic, hydraulic control valve, electromagnetic induction drive and these collaborative driving methods.
3.3 Style duty at work
Valve working style includes open and close, normally closed, short-time working system, continuous working system, intermittent cycle time working system.
3.4 valve failure Valve failure
Valve failure includes seal failure, posture failure, function failure, etc. Invalid tightness includes exposure and air leakage. Invalid posture includes drive failure, seat stuck, spool dead, etc. Functional failure varies according to different valve types, such as adjusting valve wrong, relieving pressure working pressure instability, valve not in accordance with the provisions of the working pressure bounce.
4 Installation
4.1 Preparing for Installation
4.1.1 Before valve installation, check that the product qualification certificate and installation and operation manual of the valve are complete and valid.
4.1.2 Appearance inspection shall be carried out before valve installation, which shall comply with the following provisions:
a) The surface shall not have cracks, sand holes, mechanical damage, rust, stains and other shortcomings;
b) The factory nameplate shall not fall off, and the performance parameters in the factory nameplate are consistent with the key points of system design;
c) Both sides of the valve should be maintained with safety protective cover.
d) There should be no water storage, rust, stains and damage in the oil circuit board;
e) There shall be no paint on the flange connected screw, the screw shall be intact, the sealing surface of the flange shall not be damaged by axial pipe groove and other factors, and the electric welding end weld shall be intact, and there shall be no welding mechanical damage;
f) spring type safety valve to check the integrity of the seal. Rod type valve should have heavy hammer type positioning equipment;
g) The inner surface of the body of the rubber lined pipe, pond lined porcelain and plastic lined valve should be smooth, the lining and the base material should be integrated firmly, without cracks, bulges and other shortcomings.
4.1.3 Valve opening and closing inspection and pressure test
Valve (other than valve) switch should be sensitive, position indicator accurate. Before installation, manually switch the valve power three times to see if there is a stuck condition.
The valve (other than valve) shall be left factory for more than one year, and it is proposed to carry out pressure test under conditions. The valve test for petrochemical industry and related fields shall be carried out in accordance with the relevant provisions of JB/T 9092, and the general industrial valve test shall be carried out in accordance with the relevant provisions of GB/T 13927.
4.2 Installation
4.2.1 General Requirements
4.2.1.1 Read the installation manual carefully before installing the valve.
4.2.1.2 Valves specified for inflow shall be installed in accordance with valve requirements.
4.2.1.3 In general, the valve spindle need not be installed downward to prevent the seat from being etched.
4.2.1.4 Lifting check valve should be level installed, swing check valve shaft sleeve should be level.
4.2.1.5 There is a safety release device valve, and the release valve should contain an outlet pipe, and the release orientation should not be facing the operator.
4.2.1.6 The valve installation position should be convenient for actual operation and maintenance.
The actuating mechanism is stuck due to corrosion of carbon steel torsion spring in the application of self-operated temperature regulating valve. The problem was solved by changing the torsion spring into stainless steel. (4) For the pipelines that are put into use less, some components are stuck because the self-operated valves do not work for a long time. By carrying out regular maintenance and calibration for the valve, the probability of common failures is reduced.
Self – operated temperature control valve application status
Self-reliant temperature control valve key processing technology
(1) Temperature self-regulating valve (temperature sensing point of internal structure) for heat exchanger inlet and outlet temperature control.
(2) Temperature self-regulating valve (capillary external temperature sensing point) for heat exchanger inlet and outlet temperature control.
2. Application problems occurred
(1) The spool is stuck;
(2) The valve cannot be opened;
(3) warm capillaries dehysis;
(4) The actuator is stuck;
(5) The internal structure of the actuator is corroded after condensate;
(6) The small chain of the actuator cannot be popped out after it is closed;
(7) The valve leakage is large.
3 Maintenance and maintenance countermeasures
(1) Before the relevant annual inspection, the probability of common failures is very large. Increased the relative probability of this year’s inspection. The content of this year’s inspection is: check whether there is any problem with the adjusting system, manually adjust the temperature, to see whether there is a corresponding position of the adjusting valve; Check for capillary leaks.
(2) Due to the selection of foam glue to carry out heat insulation, resulting in foam glue into the valve, so that the valve is stuck. After changing the heat insulation method, this problem is solved in time.
(3) The actuator is stuck due to corrosion of carbon steel torsion spring. The problem was solved by changing the torsion spring into stainless steel.
(4) For the pipelines that are put into use less, some components are stuck because the self-operated valves do not work for a long time. Regular maintenance and calibration are carried out for the valve to reduce the probability of common failures.
Post time: Apr-25-2023
