Challenges of Liquid Level Measurement in Strong Acid and Strong Alkali Environments

In strong acid and strong alkali environments such as chemical processing and electroplating, traditional level transmitters are highly susceptible to corrosion damage. Xi'an Shenghongchuang PTB603 anti-corrosion level transmitter adopts ceramic/PTFE anti-corrosion technology to precisely solve the measurement challenges of highly corrosive media such as sulfuric acid and hydrochloric acid, providing customized solutions for HJ833, LMP836 and other product series, helping engineers achieve safe and reliable liquid level monitoring.

In the production processes of industries such as chemicals, pharmaceuticals, and electroplating, liquid level measurement of strong acid and strong alkali media (such as 98% concentrated sulfuric acid, 40% sodium hydroxide solution, etc.) has always been a technical challenge. Ordinary 304/316 stainless steel materials may develop pitting perforation within 48 hours in media with pH values <2 or >12, leading to sensor failure. This not only causes equipment loss, but may also trigger leakage accidents, threatening personnel safety and environmental compliance.

Three Major Failure Causes of Traditional Level Transmitters

• Material corrosion: Hydrochloric acid vapor can penetrate metal grain boundaries, causing intergranular corrosion of Hastelloy transmitter diaphragms
• Seal aging: Fluororubber sealing rings can only maintain a service life of 200 hours in 80℃ concentrated sulfuric acid
• Signal drift: Hydrofluoric acid can corrode the Wheatstone bridge circuit of piezoresistive sensors

Core Technologies of the PTB603 Anti-Corrosion Level Transmitter

The PTB603 series developed by Xi'an Shenghongchuang Instrument Co., Ltd. adopts a military-grade aluminum oxide ceramic sensor head, combined with a fully wrapped PTFE (polytetrafluoroethylene) structure, achieving breakthroughs through three patented technologies:

1. Multi-layer Composite Anti-Corrosion Technology

The medium-contacting part of the sensor adopts a three-layer protection structure of "ceramic+PTFE+PVDF":

2. All-welded Sealing Process

Laser seal welding technology is used to replace the traditional O-ring seal, achieving:

• IP68 protection rating (continuous immersion at a water depth of 10 meters)
• Stability under 150℃ high-temperature working conditions
• Absolute zero-permeation sealing

3. Intelligent Temperature Compensation

A high-precision NTC chip is built in to automatically correct measurement errors caused by changes in medium temperature, ensuring that accuracy remains at ±0.2%FS within the range of -20℃~150℃.

Typical Application Scenarios and Selection Guide

For different corrosive media, Shenghongchuang provides multi-series solutions:

Preferred Options for Strong Acid Environments

• HJ833 series: Specially designed for 98% concentrated sulfuric acid, with a ceramic diaphragm thickness of 3mm
• LMP836 series: Special model for hydrofluoric acid, using a special fluorocarbon coating

Preferred Options for Strong Alkali Environments

• BXY620F series: Specially designed for 50% sodium hydroxide solution, equipped with a titanium alloy housing
• TS303 series: Specially designed for ammonia water measurement, with gas-phase anti-corrosion function

Solutions for Mixed Media

For complex media such as electroplating solutions, the following are recommended:

• T-51B model: Specially designed for phosphoric acid/sulfuric acid mixed solutions, certified to ISO 15848
• PRC-918 model: Supports customized anti-corrosion combinations (PTFE+PFA+ceramic)

Key Points for Engineering Implementation

To ensure the long-term stable operation of anti-corrosion level transmitters, note the following:

Installation Specifications

1. Avoid installation directly below the agitator to prevent mechanical impact
2. In strong acid storage tanks, the sensor must remain immersed to prevent gas-phase corrosion
3. Use installation flanges made of PTFE material

Maintenance Recommendations

• Perform zero-point calibration every 6 months (using a dedicated calibration cap)
• Regularly inspect the integrity of the cable sheath
• Establish a record file for changes in medium corrosiveness

Industry Certifications and Quality Assurance

All anti-corrosion level transmitters from Shenghongchuang have passed:

• National explosion-proof certification (Ex d IIC T6)
• SIL2 functional safety certification
• Third-party corrosion resistance test report (ASTM G31 standard)

Conclusion and Recommended Action

In the field of strong acid and strong alkali media measurement, the integration of materials science and sensor technology is driving industry transformation. With 20 years of professional experience, Xi'an Shenghongchuang provides full life-cycle services for EVT-300B, CYT-152 and other series of anti-corrosion level transmitters, including:

• Medium compatibility testing
• Operating condition simulation verification
• 3-year extended warranty

If you would like to learn about the selection solution for the AC-L3 anti-corrosion level transmitter, or obtain customized services, please contact our engineering team immediately, and we will provide you with a complete solution compliant with the API 682 standard.