After consulting a large number of documents and materials, our R&D personnel repeatedly tested, and put forward a new design method of sealing valve seat, let me introduce in detail: in view of the above problems, we have improved the contact structure of the sealing ring. Take the middle positive pressure point as the center, extend 1mm to both sides to retain the original shape, and remove 0.2mm for the rest, taking the compression amount as 0.5~0.6mm, that is, the sealing ring is compressed 0.25~0.3mm in one direction. After the valve cover is fastened, the sealing ring. The contact force is only applied on the circumference with a width of 2mm, and the contact surface with the ball force is reduced by 2/3, which can be approximately regarded as a line contact. Under the same tightening force, compared with the original seal ring, the sealing performance is improved, and the pulling torque of the handle is reduced. Even if the ball is offset △ during tightening, the boss will not be generated, so that the opening and closing torque is uniform. If concave, the sealing surface is protected. Due to the reduction of the contact area and the change of the stress state of the contact area of the seal ring, the influence of the change of the size accuracy of the parts and the change of the tightening force on the opening and closing torque and the sealing performance after tightening is reduced, thus improving the bench rate of the finished valve.

Next, let's talk about the measuring electrode of the electromagnetic flow sensor
The electrode of the electromagnetic flowmeter is in direct contact with the measured liquid, so it must be corrosion resistant, wear-resistant, leak proof and non magnetic conductive in structure. The three pairs of measuring electrodes are made of 316L, which is suitable for industrial wastewater and weak corrosive acid, alkali and salt solutions, and the price is low. The corrosion resistance of electrode to measuring medium is the first factor to consider when selecting materials. Metal materials other than 316L can be selected, such as molybdenum containing acid resistant steel, Hastelloy B, C, titanium, tantalum, platinum iridium alloys, etc. The grounding electrode is made of the same material as the measuring electrode, which can reliably and stably connect the conductive liquid as the reference point of the differential flow signal with the signal of the converter. It forms similar or approximately equal polarization potential with the liquid, and the instrument can stably output.