Mechanical professional English translation please do not use machine translation .

Affects the heat treatment process and the addition of niobium.

microstructure and mechanical properties of steel.

Mild steel weld metal.

Fan Ping, Lu Shiwei, Yunnan Zhong Li

Springer Science + Business **, Inc., 2010

Summary. Mechanical properties and microstructure.

Evaluation and analysis were carried out with a light microscope (OM).

and transmission electron microscopy (TEM) micro-microscopy

Carbon alloy steel, welded metal and niobium-free Adi—

respectively, in different heat treatment processes.

Including stress relief annealing, normalizing, none.

Post-weld heat treatment. strength and elongation.

Weld metal has been improved after no welding.

In addition to niobium, and impact toughness.

There is no noticeable effect, with the addition of . After.

Stress annealing is relieved, and the strength decreases.

nb-free weld metal, while elongation and impact.

Increases toughness. However, for niobium-containing welds.

metal, relieving stress annealing improves the force.

weld metal, and deterioration of elongation.

Impact toughness. In the normalization of the case**—

on the weld metal, the results show that with.

Hold for an increase in time at normal temperature —

A real 920? Three, the metal and none of the welds.

Note: In addition, the microstructure of the columnar crystal region.

General pipe dehumidifier) is made from a columnar grain.

One axial crystal. Equiaxed grains of grain size.

The district (Dayue) increased initially, almost remained.

Unchanged extended holding time. Root.

Mechanical properties of welds of metal and none.

Add a change that is not noticeable to increase —

In hold time. With normalization.

temperature, strength of niobium-containing weld metals.

increase, while elongation at break and impact toughness.

Significant decline. Optical microscopy and transmission electron microscopy analysis findings.

Fine particle precipitation is the norm of the NBC.

Temperature 920? Three, among which refined grains.

The impact toughness of the weld metal is improved. provided.

Increase the normalizing temperature, content.

Niobium-containing weld metal of Wechsler ferrite (workflow).

increase the number of particles while the United States.

lowered, increased strength and lowered.

Impact toughness.

Do you dare to be a little lazy, put the whole article up.

Piping Design Guidelines.

Basic guidelines for routing.

1。High energy lines need to be arranged in civil structures that have been designed with pressure newlines and other high-level priority lines, and the functional design of retention and sealing of the high-energy line wrap (HELB) area must first be laid out as a safety-related system.

2。It should be arranged to support the back and small tubes of large diameter pipes in front. Pipes that need to be regularly inspected or traced should be located to enable access.

3。Non-confidential pipelines need to be arranged from the pipelines as much as possible so as not to affect the disruption of the pipelines.

4。Safety-related components must be protected from internal and external hazards, such as the potential risk of impact, missiles, and high-energy line breaks.

5。Pipes should not be routed above the cable tray as much as possible.

6。Pipeline routes carrying flammable gases or liquids should be avoided as much as possible in areas with a potential risk of fire.

7。Pipes with temperatures above 100C should not be discharged to tanks of nearby flammable materials.

8。Insulated pipes need to be insulated or protected against the touch if the surface temperature is 60C.

9。The requirements shown on the P ID of the slope gravity piping and instrumentation should be followed.

Drain - vent.

10。Exhaust valves are inspected before discharge to maintain all fluids and require design.

11。Venting tap water needs to be designed to fill pipes with liquid, no air, after checking for maintenance pickpocketing.

12。Exhaust and drainage need to be designed to at least as much stress concentration as possible to minimize pipe dead zones.

13。If necessary, vents and drain valves should be designed to provide platforms or ladders for easy access and maintenance.

14。Depending on the pressure class, the P ID is displayed and can be applied to double drain valves. Should be installed in case of support double valves, the support double valve needs to be installed from the header row (tie back to support) in order for the thermal movement and vibration effects of the head line.

Draw 15. (suction end of the pump) diameter 3 to 5 straight pipe length is required at the suction centrifugal pump end. For other types of pumps, the length of the straight pipe section required depends on the requirements of the supplier.

16。It should be avoided at the high point of the suction line of the pump.

17。Do not route the pipeline pump, interfere with the maintenance.

18。Finding a practical close source liquid pump with piping flexibility considerations must be taken from a tank pump.

Welding 19. Where feasible, avoid welding connections between special components (e.g., valves, elbows, elbows, etc. T-shaped). Consideration should be given to the distance between two special parts of at least 1 DN. The pressure drop should be limited to. 20。

Piping Design Specifications.

Fundamental guidelines for routing.

1。High energy lines need to be arranged in the case of the retention of the design and function of the civil structure and the leakage sealing pressure of the High Energy Wrap Place (HELB), the primary wrap and other class routes must be set up first as safety-related systems.

2。Large-diameter pipes should be arranged at the back, with small pipes supported at the front. Periodic inspections or tubes, tracking are required.

Classified pipelines need to be arranged from ** pipes as much as possible so as not to affect ** pipelines in case of breaks.

4。Safety-related elements must also be protected from potential internal or external hazards such as shocks, **, missiles, and high-energy line wraps.

5。Duct routing above should not be as much as possible cable trays.

6。Areas containing flammable gases, pipelines, routes, or liquids should be protected from potential hazards.

7。pipes, the temperature should not exceed 100 C near the collapse of a tank with flammable and explosive materials.

8。Insulated pipes need to be retained or protected from contact with hot surface temperatures >> if 60 degrees Celsius.

9。The slope gravity should be followed and the p&id displayed on the piping and instrumentation should be displayed according to the requirements.

Suction: Exhaust.

10。Drain faucets need to be designed to suck up all liquids before inspection.

11。The exhaust vent is designed to fill the pipe with liquid and no air, which is inspected and repaired.

12。Exhaust and drainage need to be designed to at least be as stress-concentrated as possible, so pipe dead zones will be reduced to a minimum.

13。Exhaust and drain valves should be designed to provide easy access and maintenance of a platform or ladder if necessary.

14。Dual flow valves can be applied depending on the pressure level displayed on the P&ID. The support should be installed in the case of a double valve, the support double valve needs to be installed from the water heater line (tie back support), from the beginning of the thermal movement with the vibrating header line.

15。(Pump Impeller Suction) Centrifugal pump impeller suction for straight pipes with a diameter length of 3 to 5. For other types of pumps, the length of straight lines required is based on the requirements of the quotient.

16。High points at the pump inlet line should be avoided.

17。Do not pump in the pipeline route, as this will hinder maintenance.

18。Located close to the pump as long as feasible**, from the liquid injection tank to the tank taking into account the flexible welding of the pipeline.

19 years old. Special welded connection parts (e.g. valves in elbows, t-pieces...)in elbows, etc.) should be avoided where feasible. The distance of at least 1 dn should be considered between two special parts. There should be a pressure drop.

Piping Design Guidelines.

Basic guidelines for routing.

1。High-energy lines need to be set up in high-energy wires broken (Helb), civil structures have been designed for functionality, retention and tightness if the line breaks and other priority class lines must be developed first-class safety-related systems.

2。Large diameter pipes should be provided at the back and the front end support of small pipes. Pipes need to be inspected regularly or traced and pipes should be located to enable access.

The column pipe needs to be set as far as possible from the **pipe, so as not to affect the breaking of the **pipe.

4。Safety-related components must be protected from potential risks such as internal or external risks, **, missiles and high-energy line breaches.

5。Tubes should not be routed above the cable tray as much as possible.

6。Routing pipes containing flammable gases or liquids should be avoided in areas with potential fire hazards.

7. The temperature is higher than 100. Tubes should not be routed in tanks with flammable materials.

8。Heat retention required for heat preservation or prevention of contact with surface temperature60 .

9。The slope should follow the gravity tube and the instrument should be displayed in the P&G ID as required.

Drain venting.

10。Drain faucets need to be designed to be repaired before draining all liquids.

11。The exhaust tower design needs to be checked for maintenance after filling up the tube liquid without air pockets.

12。The need for ventilation and drainage is designed, at least possible, where stress concentrations are made, so that pipe dead zones are minimal.

13。Ventilation and drain valves should be designed to be easily accessible and maintained, providing platforms or ladders, if necessary.

14。Dual drain valves can be applied to different pressure values shown in the P&G ID support should be installed in the case of dual valves and dual valves and support, which need to be installed on the headline (back support), which is less affected by thermal movement and vibration.

Pump 15. A length of 3 to 5 diameter straight pipe sections (suction side of the pump) is required for side suction centrifugal pumps. For other types of pumps, the length of straight pipe required depends on the requirements of the supplier.

High 16. Suction lines in the pump should be avoided.

17。Do not place the pump in the pipeline, as this will hinder maintenance.

18. Positioning the pump. Try to make the source liquid to be pumped from the tank considering the flexibility of the pipeline.

Welding 19. Special parts between welded connections (e.g. valve elbows, tee elbows, etc.) should be avoided where feasible. A distance of at least 1 should not be considered a special part between the two countries. Pressure drop should.