German dvb seals dvb models dvb prices

dvb seals can be divided into two main categories: static seals and dynamic seals. Static seals mainly include three types: gasket seals, sealant seals, and direct contact seals. According to working pressure, static seals can be further divided into medium-to-low pressure static seals and high-pressure static seals. Medium-to-low pressure static seals commonly use gasket seals made of softer materials with wider widths, while high-pressure static seals use metal gaskets made of harder materials with very narrow contact widths. Dynamic seals can be divided into two basic types: rotary seals and reciprocating seals. Others are classified as contact seals and non-contact seals based on whether the seal contacts the components moving relative to it; based on the seal and contact position, they can be divided into circumferential seals and face seals, with face seals also known as mechanical seals. Centrifugal seals and spiral seals in dynamic sealing achieve sealing by imparting kinetic energy to the medium during machine operation, hence they are sometimes referred to as hydrodynamic seals.

dvb Seal Classification

1) Packing seal: The packing seal features a simple structure, low cost, and easy maintenance. However, it has high leakage volume and significant power loss. Therefore, packing seals are used for conveying general media, such as water; they are generally not suitable for petroleum and chemical media, especially for valuable, flammable, explosive, or toxic media. 2) Mechanical seal: A mechanical seal (also known as a face seal) provides good sealing performance with minimal leakage and long service life, but it is expensive and requires higher standards for machining, installation, maintenance, and repair compared to general seals. Mechanical seals are suitable for conveying petroleum and chemical media and can be used for media with various viscosities, strong corrosiveness, and solid particles. The American Petroleum Institute standard API610 (8 edition) stipulates that cartridge mechanical seals shall be installed unless otherwise specified by the user. 3) Dynamic seal: Dynamic seals can be divided into two types: back-vane seals and auxiliary impeller seals. During pump operation, the centrifugal force of the back vanes (or auxiliary impeller) reduces the pressure of the medium at the shaft seal to atmospheric or negative pressure, preventing leakage during use. When the pump stops, the centrifugal force disappears, and the sealing effect of the back vanes (or auxiliary impeller) fails; at this point, the stationary sealing device provides the sealing function. Packing seals are commonly used in the stationary sealing devices associated with back-vane (or auxiliary impeller) seals. There are two types of packing seals: standard type and mechanically adjustable tension type. Standard packing seals are similar to those in general packing-seal pumps and require maintaining a slight positive pressure at the shaft seal to prevent dry friction of the packing. Mechanically adjustable tension packing seals use counterweights to loosen the packing during pump operation and tighten it when the pump stops. Dynamic seals offer reliable performance, low cost, and easy maintenance, making them suitable for conveying media with a high content of solid particles, such as slurry pumps and ore pulp pumps in the phosphate industry. The disadvantages are greater power loss compared to mechanical seals and shorter service life of the stationary sealing device. The seal between the rotating pump shaft and the stationary pump casing is called the shaft seal. Its function is to prevent high-pressure liquid from leaking out along the shaft or outside air from entering along the shaft. For centrifugal pumps, the shaft seal is a type of dynamic seal. Depending on whether the sealing surfaces are in contact, dynamic seals can be classified as contact dynamic seals and non-contact dynamic seals. In contact dynamic seals, the sealing device contacts the shaft, resulting in relative friction between the two. Contact dynamic seals include packing seals and mechanical seals.

dvb Seal Operation

1) If slight leakage occurs after the pump starts, observe it for a period. If the leakage does not decrease after continuous operation for 4 hours, stop the pump for inspection. 2) The pump operating pressure should be stable, with pressure fluctuations not exceeding 1 kg/cm². 3) During pump operation, avoid cavitation to prevent dry friction and damage to the sealing surfaces. 3) Check the sealing condition regularly. During operation, if leakage exceeds the standard (not more than 5 drops/min for heavy oil, not more than 10 drops/min for light oil), and there is no improvement within 2-3 days, stop the pump to inspect the sealing device.

dvb Seal Installation Precautions

1) Pay close attention to avoiding installation deviations during installation. Tighten the gland after aligning the coupling. Tighten the bolts evenly to prevent tilting of the gland face. Check each point with a feeler gauge; the error must not exceed 0.05 mm. Check the fit clearance (i.e., concentricity) between the gland and the outer diameter of the shaft or shaft sleeve; it must be uniform around the circumference. Check each point with a feeler gauge; the allowable error must not exceed 0.01 mm. 2) Compress the spring according to regulations; excessive or insufficient compression is not allowed. The required error is 2.00 mm. Excessive compression increases the specific face pressure, accelerating face wear. Insufficient compression results in inadequate specific pressure, failing to achieve sealing. 3) After installing the rotating ring, it should automatically spring back when pressed against the spring. 4) Installation position requirements: To ensure stable operation, long service life, and low leakage of the mechanical seal, correct installation on the machine is crucial. Before installing the mechanical seal on the machine, carefully compare it with the general assembly drawing to confirm that all parts are ready. Pay attention to any abnormalities such as scratches or defects on the sealing faces of the friction pair and sealing rings. Also check for scratches on the shaft or shaft sleeve surfaces and flanges that contact the packing and sealing rings (O rings). If any abnormalities are found, replace or repair before use. During actual installation, do not bring unnecessary parts to the site. If parts remain after installation, it indicates missing installations; if parts are insufficient, it means parts were assembled in unnecessary places, serving as a self-check during installation.

Weidou Intelligent Technology professionally sells German dvb seals, dvb sealing rings, dvb sealing strips, dvb pipe seals, dvb cable seals, dvb rubber seals, dvb mechanical seals, dvb sealing gaskets, dvb oil seals, dvb shaft seals, dvb metal seals, dvb high-pressure seals, dvb spiral seals, dvb centrifugal seals, dvb sealing rings, dvb original German imports. Welcome customers to inquire and order.