Ganoderma extract (Ganoderma Lucidum
extract/Reishi Mushroom Extract) is extracted from top-graded organic
shell-broken Ganoderma Lucidum spore powder using advanced modern technology. Spores
are the seeds of Ganoderma Lucidum. When it matures, the spores are released
from the mushroom cap. They are also where most of the nutrients of Ganoderma
Lucidum are contained. In order to allow the nutrients inside the spore powder
to be fully absorbed by human body, we used a patented technology called low
temperature physical shell-breaking technology to crack the cell wall of
Ganoderma Lucidum spore powder.
The Ganoderma we used for this product comes
from our self-built organic Ganoderma farm at Mt. Wuyi. Both the farm and the
GMP workshop have acquired organic certifications from 4 countries and regions
including Chinese, Japan, the US, and the EU. We do not use any type of
herbicide, pesticide, or chemical fertilizer during the whole cultivation
process, delivering the best and safest product to our customers.
By using
extraction technology, we can increase the concentration of Ganoderma
polysaccharides and triterpenes in the product. Reishi Mushroom Powder polysaccharides and
triterpenes both work together to enhance human`s immune system, fighting
against diseases and infections. Also, Ganoderma can help protect the liver,
increase sleep quality as well as relive stress.
Ganoderma Extract Ganoderma Extract,Reishi Mushroom Extract,Organic Ganoderma Extract,Ganoderma Lucidum Powder Fujian Xianzhilou Nutra-Industry Co., Ltd , https://www.ganoherb.com
4.1 Metal hollow O-rings Metal hollow O-rings are high-precision annular rings welded by thin-walled copper tubes, stainless steel tubes, nickel alloy tubes or Monel tubes. According to different requirements, the surface of the O-ring can be plated with gold, silver, platinum, copper, nickel, etc. or fluoroplastic. The purpose of the hollow is to adjust the pressure inside the tube to improve the sealing performance. Its sealing features are: 1 wide temperature range (-270 ~ 1000 °C); 2 use pressure range from 1.33 × 10 -16 MPa ultra-vacuum to high pressure of 300MPa or more (even up to 2000MPa); 3 can be in rubber O Gases and liquids (such as organic solvents) that cannot be used in the ring. Metal hollow O-rings are used in a wide range of applications, such as static sealing on high temperature engines, high pressure forming machines, vacuum vessels, nuclear reactors and the like.
4.1.1 Classification of metal hollow O-rings Metal hollow O-rings are available in basic, open and inflatable versions:
1) Basic metal hollow O-ring (Fig. 29.6-19a) The inner cavity of the ring is a normal pressure. It is hollow to maintain a large elasticity, and the pressing force cannot be too large. It is suitable for vacuum to 7 MPa. Used internally.
2) Open-celled metal hollow O-rings (Fig. 29.6-19b). It is drilled into the inside or outside of the basic metal hollow O-rings to make the inner cavity of the tube communicate with the medium. When the pressure of the fluid rises, the pressure in the lumen of the tube also increases, so that the pressing force on the sealing surface changes as the fluid pressure changes. This self-tightening effect greatly improves the sealing effect, and the sealing ring can be used for sealing at a pressure portion of 7 MPa or more.
3) Inflatable metal hollow O-ring (Fig. 29.6-19c) is sealed with inert gas inside the metal ring. The size of the sealing is often determined by the thickness of the pipe wall. The gas pressure is 3.5MPa, 7MPa, 10.5MPa. This kind of metal ring is suitable for high temperature sealing, because of its different materials, temperature resistance is also high or low. For a soft nickel-plated metal hollow O-ring, its high temperature can exceed 815 °C.
In addition to the commonly used O-section, the metal hollow ring has prismatic and double-sided shapes, as shown in Figure 29.6-20. Figure 29.6-20a is an elliptical hollow ring whose sealing action is achieved by the strong elasticity of the ring in close contact with the groove wall. Figure 29.6-20b is a prismatic hollow ring which is sealed by the upper and lower edges and has a flattening degree smaller than that of the standard hollow ring, preferably 10%. Figure 29.6-20c is a double-angled hollow ring, which is also sealed by the upper and lower edges. The mounting groove is wider and the flatness is less than 10%. The common sealing structure of metal hollow O-rings is shown in Figure 29.6-21.
Figure 29.6-19 Standard version of metal hollow O-rings
a) basic metal hollow O-ring; b) open-hole metal hollow O-ring; c) inflatable metal hollow O-ring
Figure 29.6-20 Cross-sectional shape of the metal hollow ring
a) elliptical hollow ring; b) diamond hollow ring; c) double diamond hollow ring
Figure 29.6-21 Common sealing structure for metal hollow O-rings
If the sealing surface of the metal hollow O-ring is rough, there are defects such as cracks, scratches, bumps, etc., and the yield deformation of the material is small, which is insufficient to fill all the gaps and irregularities, and leakage will inevitably occur. To be effectively sealed, the roughness of the sealing surfaces of the rings and grooves must be guaranteed. When the liquid seal, the groove surface roughness R a in the 1.6 ~ 1.8μm, less sealing gases and volatile liquids, R a should not exceed 0.4μm. For sealing precious, rare, highly toxic gases and light liquids, the surface roughness of the sealing surface should be lower.
In addition, the wall thickness of the hollow ring is also one of the important factors affecting the tightness. For sealing gases and volatile liquids, thicker tubes are available. When installed, the compression of the hollow ring is generally 20% to 30%.
The choice of metal hollow O-rings is usually based on the operating temperature, working pressure and physical and chemical properties (corrosive, radioactive, flammability, volatility, toxicity, viscosity, density and permeability, etc.) of the media. The choices are: the material of the ring, whether it is coated or coated, the form used, etc.
4.2 Elliptical sealing ring Figure 29.6-22 shows an oval sealing ring made of plastic metal (such as copper). This type of sealing ring is suitable for various media, and has the advantages of low production cost, reliable sealing and wide applicability.
The sealing action of the oval sealing ring after pressing is achieved by filling the microscopic unevenness of the flange sealing surface after the sealing material yields. The sealing ring begins to contact the flange with a round wire. Since the material of the sealing ring is plastic with respect to the flange, the round wire portion is yielded after the bolt is tightened. As the pre-tightening force of the bolt increases, the yielding round line gradually becomes wider and becomes a torus. As long as a certain critical value is reached, the medium pressure can be sealed, and the whole of the sealing ring is still in an elastic state.
Today, DN100 copper seal ring is used as the standard sample, its size is d=129mm; D=134mm, h=2.3mm, (see Figure 29.6-22). Sealing performance test: Sealing when the medium does not leak under preload The unit pressure is 81 MPa, and the corresponding critical sealing surface width (contact surface width) is 3.5 mm.
Figure 29.6-22 Specimen size table 29.6-48 Selection of metal hollow O-rings Conditions of Use Circle type material Plating and coating Temperature / °C Pressure / MPa -250～100 10 -6 to 3.0 Basic type In the case of stainless steel, aluminum and cryogenic conditions, the ring and flange bolts are of the same material. In the case of general gas or volatile liquid media, the surface of the ring is plated with silver or coated with tetrafluoroethylene. Open type 100~300 10 -6 to 3.0 Basic type stainless steel In the case of general gas or volatile liquid media, the surface of the ring is plated with silver or coated with tetrafluoroethylene. Open type 300~400 ≤4.0 Basic type Inconel Generally, when the gas or volatile liquid is used, the surface of the ring is silver plated. >4.0 Open type >400～540 Inflatable >540～700 ≤4.0 Inflatable Inco Nickel X Alloy silver >4.0 Open type
The elliptical section of the seal should have a long axis greater than 2 times the width of the seal face and a ratio of the major axis to the minor axis of 3. The data can be referenced in the design.
Metal seal 4.1.2 Selection of metal hollow O-rings Metal hollow O-rings are the resilience generated by the deformation (squashing) of the hollow ring, which causes a certain stress on the sealing surface. This stress causes the material of the hollow ring to yield and match. The unevenness on the sealing groove makes the sealing surface of the ring and the groove tightly fit to achieve sealing. Elliptical cross-section seals have been used in manholes, hand holes and pipes, water and oil lines, air compressors and air equipment in steam and oil-fired boilers.