Instruments & Valves

In order to ensure that the elastic element of the pressure gauge can work reliably within the safe range of elastic deformation, the measuring range of the pressure gauge should not only be selected according to the size of the measured pressure, but also consider the speed of the measured pressure change, and the measuring range should leave enough room.
1, the use of pressure gauge to measure the stable pressure, the maximum working pressure should not exceed the range of 2/3;
2, the use of pressure gauge to measure the pulsating pressure, the maximum working pressure should not exceed the range of 1/2;
3, the use of pressure gauge to measure high pressure, the maximum working pressure should not exceed the range of 3/5. In order to ensure the accuracy of measurement, the minimum working pressure should not be less than 1/3 of the range. According to this principle, calculate a value according to the maximum pressure measured, select a measuring range slightly larger than the value from the pressure gauge product catalog;
4, should be selected according to the working pressure of the boiler, the limit value of the range scale should be 1.5~3.0 times of the working pressure, preferably 2 times.
Summary: When measuring steady load, the measured load shall not exceed 2/3 of the upper limit of the pressure gauge; When measuring the fluctuation pressure, the load must not exceed 1/2 of the upper limit of the pressure gauge; The minimum pressure measured by the pressure gauge should not be less than 1/3 of the upper limit of the pressure gauge.

First of all, it is necessary to find out which industry the equipment is to be used in (such as: die casting, pressure plate, reaction kettle, rubber, extrusion, injection molding, etc.), and then calculate the heating power through the process parameters; The next is to calculate the head and flow of the circulating pump; Then according to the temperature selection, flow, head to choose which pump to use; Then select the control mode suitable for use.

Gear pumps can be used when viscous fluids containing no solid particles need to be transported under high pressure.Therefore, gear pumps are suitable for pumping highly viscous materials at high temperatures and are also capable of reversing the pumping direction.Gear pump is characterized by constant flow and low noise during operation. Gear pumps are usually reliable, compact, and simple in design, so maintenance costs are not high. However, it is not ideal for high flow use; Gear pumps are widely used in the automotive industry to lubricate all engine parts. They are also often used in the plastic processing, automatic press or casting industry; Gear pumps can also provide quantitative functions.

Before choosing the temperature measuring instrument, it is necessary to understand the technological process, medium, operating pressure, ambient temperature, medium flow rate and other conditions. According to the process conditions and requirements to determine the measuring point, choose the appropriate hot sleeve material and installation. Threaded hot tubing is easy to install, but the pressure rating is low, easy to leak, not suitable for pipelines and equipment containing corrosive and toxic media. The welded hot sleeve is connected with the process pipe by welding, which is not easy to disassemble. It is suitable for the occasions involving high temperature and high pressure and leakage prevention. Flange type hot sleeve is connected with process pipe through butt flange, easy installation, high rated pressure value, suitable for high temperature and high pressure, corrosive environment.
The insertion depth and profile type of hot casing are determined according to the technological conditions. The insertion depth should reach the representative area where the temperature change of the measured medium is sensitive.The bar profile is divided into straight type, step type and cone type, according to the required pressure rating and tensile force to select the appropriate model.