In mechanical design and manufacturing, you often encounter tolerances marked on technical drawings, such as Φ20±0.02, 20+0.01/−0.03, or H7/g6. Almost everyone who has looked at such drawings has asked the same questions: Why are some tolerances so strict? Why are some dimensions given default tolerances, while others are specified individually? Why are geometric tolerances like […]
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1. Nitrogen-Hydrogen Compressor Stage 3 Outlet Pressure Display is Lower Than the Local Pressure Gauge Fault InspectionThe pressure displayed on the control panel is 0.6 MPa lower than the local pressure gauge. We checked and calibrated both the pressure gauge and the pressure transmitter, and both were accurate. However, the two readings still did not
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When using a differential pressure flowmeter to measure steam, where exactly should the shut-off valve on the pressure tap be installed — before or after the condensation tank? According to some literature, it should be installed after the condensation tank. However, in practice, most installations place it before the tank. Which of these is correct?
Gaskets are commonly used components in industrial equipment. But have you installed them properly? Incorrect installation can lead to gasket damage and even hazardous situations. Below is a step-by-step guide to ensure correct gasket installation. Tools You’ll Need for Installation Before starting, make sure to prepare the following tools: A calibrated torque wrench, hydraulic tightening
Sealing Matters: Is Your Gasket Installed Correctly? Read More »
1. What is Sampling? Sampling refers to the process of measuring and recording a continuous-time analog signal at fixed intervals, thereby converting the continuous-time signal into a discrete-time sequence. Sampling transforms the time axis from a continuous domain into an integer-indexed domain, allowing the signal to be processed by digital systems. The sampling rate is
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In the chemical industry, measuring the liquid level in sodium hydroxide (caustic soda) storage tanks has long been a challenging issue. Due to its strong corrosiveness, tendency to crystallize, and steam emissions, traditional instruments often “fail” in such conditions. In this article, we’ll explore how to address this challenge. Key Physical Parameters for Monitoring Sodium
This seemingly simple question has caused confusion for many companies and designers. Some choose to install cut-off valves, while others don’t, with practices varying widely. But what do the standards say? Are there clear requirements in the regulations? In this article, we will clarify the principles for the installation of cut-off valves in safety valve
Should a Cut-off Valve Be Installed in the Inlet and Outlet Pipelines of a Safety Valve? Read More »
Components of Process Control Instruments Transmitter UnitThe transmitter unit converts measured parameters (such as set parameters in an automatic control system) into standardized signals for indication, recording, or control. Common types of transmitters include pressure transmitters, differential pressure transmitters, flow transmitters, temperature transmitters, differential temperature transmitters, and level transmitters.Transmitters can be categorized into two types
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RF Capacitance (or RF Admittance) Level Switches are vital instruments for industrial liquid level measurement. The core principle behind their operation is based on changes in capacitance. A rod-type RF capacitance probe measures the change in capacitance between the probe and the container wall to determine the level, ensuring reliable liquid level monitoring. Although this
1. Abnormal Cumulative Flow in Mass Flow Meter Troubleshooting: A mass flow meter at a plant showed cumulative flow even when there was no process flow. Upon inspection, it was found that the supports at both ends of the sensor did not meet installation requirements. Specifically, the support distances were uneven, and the bottom of
