What is a disc, the difference between the seat and the disc and the spool

Seat Ring The detachable face part of the valve is used to support the fully closed position of the spool and form a sealing pair. Generally, the seat diameter is the maximum flow diameter of the valve. For example, butterfly valves have a wide range of seat materials, all kinds of rubber, plastic, metal materials can be used as seat materials, such as:

EPDM, NBR, NR, PTFE, PEEK, PFA, SS315, Stellite, etc.

The same goes for the disc.

The spool and disc are the same thing.

The valve disc is one of the main core parts of the valve, which directly bears the pressure of the medium in the valve, and the materials used must meet the requirements of "pressure and temperature level of the valve".

The commonly used materials are as follows:

1. Gray cast iron: Gray cast iron is suitable for water, steam, air, gas and oil with a nominal pressure of pn and a temperature of 10 200. The commonly used grades of gray cast iron are: HT200, HT250, HT300, HT350.

2. Malleable cast iron: suitable for water, steam, air and oil medium with nominal pressure pn and temperature of 30 300, commonly used grades are: KTH300-06, KTH330-08, KTH350-10.

3. Ductile iron: suitable for PN, water, steam, air and oil at a temperature of 30 350. Commonly used grades are: QT400-15, QT450-10, QT500-7.

In view of the current domestic technology level, the factories are uneven, and it is often not easy for users to inspect. As a rule of thumb, it is recommended that the valve is still made of steel for safety.

4. Acid-resistant high silicon ductile iron: suitable for corrosive media with nominal pressure pn and temperature lower than 120.

5. Carbon steel: suitable for water, steam, air, hydrogen, ammonia, nitrogen and petroleum products with nominal pressure pn and temperature of 30 425. Commonly used grades are WC1, WCB, ZG25 and high-quality steel and low-alloy structural steel 16Mn.

6. Copper alloy: suitable for PN water, seawater, oxygen, air, oil and other media, as well as steam medium with a temperature of 40 250, the commonly used grades are ZGNSN10ZN2 (tin bronze), H62, HPB59-1 (brass), QAZ19-2, QA19-4 (aluminum bronze).

7. High-temperature copper: suitable for steam and petroleum products with nominal pressure PN temperature 570. Commonly used grades are ZGCR5MO, 1CR5M0

ZG20CRMOV, ZG15GR1MO1V, 12CRMOV, WC6, WC9 and other grades. The specific selection must be in accordance with the provisions of the valve pressure and temperature specifications.

8. Low-temperature steel, suitable for nominal pressure PN, temperature -196 ethylene, propylene, liquid natural gas, liquid nitrogen and other media, commonly used grades) ZG1Cr18Ni Cr18Ni9, 1Cr18Ni9Ti, ZG0Cr18Ni9 9. Stainless acid-resistant steel, suitable for nominal pressure PN, temperature 200 Nitric acid, acetic acid and other media, commonly used grades are ZG0CR18NI9TI, ZG0CR18NI10 "nitric acid resistance", ZG0CR18NI12MO2TI, ZG1CR18NI12MO2TI "Acid Resistant and Urea".

1. The roles of the three are different:

1. The function of the valve seat: it is used to support the fully closed position of the valve core and form a sealing pair.

2. The function of the valve disc: the valve disc is a spherical disc, which can maximize the increase and minimize the pressure drop. Hardened for maximum service life.

3. The function of the valve core: the valve core in the pressure reducing valve is one of the main components to achieve pressure control.

The characteristics of the two and three are different:

1. Characteristics of valve seat: corrosion resistance and wear resistance; Longer working hours; High pressure resistance; High dimensional accuracy; Excellent resistance to thrust loads and high temperatures; It is suitable for most passenger vehicles, light and heavy trucks, diesel engines and stationary industrial engines.

2. Characteristics of the valve disc: It has the function of adjustable positioning to avoid the penetration and excitation of the valve body shell wall. The unique flip-up disc check valve has a built-in disc hinge pin that eliminates possible leakage from hinge pins that penetrate the housing, and because the machined bracket is parallel to the seat surface, the disc seat can be adjusted when the seat is serviced.

3. The characteristics of the valve core: when the rotor is rotated, the fork at the lower end of the rotor drives the moving valve to rotate, so that the water outlet through hole on the moving valve plate corresponds to the water inlet through hole on the static valve plate, and finally the water flows out from the through hole on the rotating core, and this design is widely used in the faucet outlet.

Third, the three have different overviews:

1. Overview of the valve seat: the use of elastic sealing materials and small actuator thrust to obtain the bubble tight seal, compression of the seat sealing stress to make the material elastic deformation and squeeze into the rough surface of the metal parts to block all the leakage paths. The permeability of the material is the basis for a small amount of leakage to the fluid.

2. Overview of valve disc: the granular-type disc sealing ring discs disclosed, and the utility model discloses a kind of skirt-type disc sealing ring, and its structural characteristics are that the sealing of the sealing ring and the disc body is a double-edged line seal, and the longitudinal section between the blade line and the blade line at the sealing place of the sealing ring and the disc body is a trapezoidal plane space.

3. Overview of the valve core: The valve core is the valve part of the valve body that realizes the basic functions of direction control, pressure control or flow control with the help of its movement.