In Petro and chemical industry for flange connections Stud Bolts and Hex Bolts are used
The quantity of bolts for a flange connection will be given by the number of bolt holes in a flange, diameter and length of bolts is dependent of flange type and Pressure Class of flange.
Stud Bolt length are defined in Asme B16.5 standard. The length in inches is equal to the effective thread length measured parallel to the axis, from the first to the first thread without the chamfers (points). First thread is defined as the intersection of the major diameter of the thread with the base of the point.
1) Standards: Based on DIN & ANSI & JIS & IFI
and per drwing
2) Material: carbon steel, alloy steel, stainless steel
3) bolt Size: M4-M42,3/8"--7/8"
4) bolt Surface: Plain,Zinc ,HDG,DAC,Geomet
5) bolt Thread: UNC, UNF, Metric Thread
6) bolt Quality control : ISO 9001
7) bolt Package : Small box ,Poly Bag,Carton+Pallet
Grades of Stud Bolts
Below a table with materials and grades for flanges, thread rods (bolts) and nuts, arranged on design temperature, flanges, thread rods and recommended nuts.
DESIGN
FLANGES
GRADE
GRADE
TEMP.
THREAD RODS
NUTS
-195° to 102°C
ASTM A182
A320 Gr.B8 Class2
A194 Gr.8A
Gr. F304, F304L, F316,
F316L, F321, F347
-101° to -47°C
ASTM A350
A320 Gr.L7
A194 Gr.7
Gr.LF3
-46° to -30°C
ASTM A350
A320 Gr.L7
A194 Gr.7
Gr.LF2
-29° to 427°C
ASTM A105
A193 Gr.B7
A194 Gr.2H
428° to 537°C
ASTM A182
A193 Gr.B16
A194 Gr.2H
Gr.F11, F22
538° to 648°C
ASTM A182
A193 Gr.B8 Class1
A194 Gr.8A
Gr.F11, F22
649° to 815°C
ASTM A182
A193 Gr.B8 Class1
A194 Gr.8A
Gr. F304H, F316H
DESIGN
FLG'S
GRADE
GRADE
TEMP.
THREAD RODS
NUTS
Should any inquiry related to stud bolts and nuts , please don`t hesitate to contact us .
Price for stud bolts and nuts are available .
Stud Bolt Stud Bolt,Directly Stud Bolt,Fasteners Stud Bolt, Grade B7 Stud, 2H Heavy Hex Nut, ASTM A193 Stud Bolt, A193 GR b7 Stud Bolt Shijiazhuang Bang dong Pipeline Technology Co,Ltd. , http://www.bd-pipefitting.com
Magnetic pump bearings are divided into two types of radial sliding bearings and thrust sliding bearings, respectively, to support the rotor rotary motion and limit the axial movement of the role, while reducing the movement wipe. As shown in Figure 1. Sliding bearings for hard graphite sleeve, set in the magnetic bearing housing at both ends. The thrust sliding bearing is a pair of relative two parts, a part of which is sheathed on the impeller or inner magnet body, made of cemented carbide and the other part is connected with the plain bearing, the sliding bearing is attached to the bearing body end. Bearing lubrication relies on graphite good self-lubricating properties, at the same time in the bearing body opened a flow hole, the high-pressure liquid medium introduced between the magnet body and the isolation cover to reduce magnetic turbulence and hysteresis caused by magnetic loss The temperature rise of the steel body, then the liquid through the pump shaft center hole, part of the cooling and lubrication of the bearing, and some return to the impeller entrance, play a role in circulating cooling and lubrication. Magnetic pump axial force through the impeller on the balance hole drilling impeller set before and after the seal ring and the bearing body at a flow hole, the high-pressure liquid introduced between the magnet body and the isolation between the rotor in the hydraulic effect Under automatic balance. Magnetic bearing lubrication principle and the rotor axial force balance principle to the magnetic pump to provide a sound theoretical basis, so the pump can generally be stable during the initial run, low noise, completely lost: a good state of leakage. However, with the advancing of running time, the defect of bearing appears under the continual function of liquid hydraulic force. 1) Automatic witnessing of the liquid does not provide an absolute balance between the axial thrust of the rotor. This is due to the structurally incomplete symmetry of both sides of the rotor subjected to hydrodynamic forces. As a result, the rotor will be subjected to a total thrust directed in one direction under any condition, and the thrust bearing in this direction will be compressed by two parts and will be relatively slidingly rubbed. 2) In some cases, the increase of total axial force of the rotor or commutation will lead to the increase of the thrust bearing load: â‘ The fluctuation of pump operating conditions is large. In the actual operation if the operating parameters (inlet pressure, outlet pressure) fluctuations, destroy the magnetic force balance of the rotor pump, the bearing to bear the greater radial force and axial force; Absorption tower circulating pump set 2, opened one prepared. Process in order to verify the spare pump is intact, to ensure that the standby pump can be enabled at any time, usually a half an inverted pump (that is, open and standby pump wheel open and stop), and each time the magnetic pump open or stop the impeller on both sides of the liquid Medium pressure has a short period of time the process of high and low exchange rate, resulting in reverse thrust within a short period of time, thrust bearing thrust at this time by the collision. 3) Due to these characteristics of the axial force of the actual operation of the magnetic pump, the thrust bearing requires not only good wear resistance, hardness, etc., but also must have high compressive strength, toughness, crush resistance, mechanical shock resistance . The hard graphite compressive strength and toughness is poor, which is easy to break down the magnetic pump operation, rupture, fragments were taken away by the media, the liquid eddy current, the axial movement of the rotor displacement increases, radial Increased vibration, radial graphite bearing squeezed by the shaft, impact damage. At the same time within the magnet body, the bearing body and the impeller seal ring and other magnetic pump friction between the inner parts of the friction, noise enhancement, reduced pump out until it can not run. Measures and effects 1) choose the appropriate bearing materials. Bearing parts of all friction pair are made of high quality silicon carbide. High purity silicon carbide, silicon carbide content of more than 99%, resistant to ammonia corrosion, with high strength, elasticity, toughness and wear resistance, so that the anti-extrusion bearing, greatly enhanced impact resistance, service life is the other sliding Bearing (such as graphite) more than 10 times. 2) Use appropriate thrust bearing clearance when installing the rotor. By installing the rotor on the bearing body and pushing the rotor aside, the maximum clearance between the thrust bearing and toilet components of the original blue magnetic pump can be measured (the maximum axial runout j Adjust it to 0.3-0.5 mm between 0.13-0.15 This clearance range is conducive to the formation of interstitial liquid film and reduce the friction between two friction pairs of thrust bearing and reduce the impact strength when collided 0 3) Optimize the operation of the process, to minimize or avoid fluctuations in the working conditions; extend the period of the inverted pump to 2 months to minimize the adverse effects of frequent inverted pumps on the magnetic pumps. 4) The improved magnetic pump is concerned with the operation of the process in operation, showing the inherent characteristics of the magnetic pump, and has good running performance, maintenance-free for a long period of time, reliable operation, maintenance cycle of about a year to ensure that The longer cycle of equipment operation. Conclusion 1) CQB80-65-125 magnetic pump bearing failure is due to inappropriate material selection, etc., can be properly selected to solve. At the same time, due to the characteristics of the magnetic pump in many ways it is different from the traditional centrifugal pump, so the process, installation, operation and other aspects of lessons learned to take some measures and ways to ensure its longer cycle, reliable and smooth operation o 2) Magnetic pump with small vibration, low noise, safe, efficient, energy-saving features for conveying corrosive, toxic, flammable, explosive, expensive or easy to vaporize the liquid and so on. In addition, due to its completely leak-free advantages, it has successfully solved the problem of dripping and dripping during fluid transportation. It has become an irreplaceable product in environmental protection projects. It is very suitable for working media or complex product components, and has a long operation history , Severe aging equipment, the urgent need to update the petrochemical and other construction of a long time old enterprises in the selection of transformation and updating, in order to change the small machine environmental protection technology behind the status quo.