Stainless steel capillary tube Manufacturers

Precision Stainless Steel Capillary Tubes for Measurement and Control Systems

As a China-based Stainless steel capillary tube manufacturer, Jiangsu Zhaolong Electrics Co., Ltd. supplies drawn stainless steel capillary tubes for temperature and pressure measurement systems. Our capillary tubes are used as pressure-sensing lines for pressure gauges and pressure transmitters, as thermal-sensing leads for temperature sensors, and as signal-transfer paths in HVAC, refrigeration, boilers, compressors and chemical reactors.

Founded in 2005, we operate a 33,300 m² plant in Jiangsu, China, with around 100 skilled employees. As a regional high-tech enterprise and production base for temperature sensors and temperature control instruments, we have developed thermocouples, thermal resistances and control electronics together with R&D institutions and academies in Shanghai. Capillary tubes are produced in the same controlled environment, using stainless steel selected for corrosion resistance, dimensional stability and predictable performance.

How Capillary Tube Quality Affects Measurement Performance

The bore diameter, surface finish and material of a capillary tube determine signal response, system tightness and service life. Our manufacturing approach keeps these variables controlled so the tube behaves predictably once connected to a sensor, gauge or transmitter.

• Precise internal diameter: a consistent cross-section along the full length reduces pressure loss and response lag in filled or fluid-sensing systems.
• Smooth internal finish: a polished bore prevents particle accumulation and flow restriction, supporting stable readings over time.
• Corrosion-resistant stainless steel: the tube withstands moisture, chemical exposure and repeated heating and cooling without degrading.
• Mechanical strength: stainless steel resists bending, crushing and accidental impact during installation and maintenance.
• Thermal stability: the tube maintains its structure through repeated thermal cycles, helping the connected instrument remain consistent.

Range and Configuration Approach

We supply capillary tubes as plain cut lengths or as complete assemblies with fittings, protective sleeves and instrument connectors. Because a capillary tube is part of a larger measurement loop, we confirm the interface details on both the instrument side and the process side before production.

Application Fit and Integration

Capillary tubes are used wherever a pressure or temperature signal must be moved from a process point to a controller, display or transmitter. We match the tube specification to the instrument type and the surrounding environment rather than treating it as a generic commodity tube.

• Industrial temperature and pressure monitoring: boilers, compressors, chemical reactors, petrochemical skids and natural gas systems.
• HVAC and refrigeration: accurate transmission of temperature and pressure readings to controllers for consistent system performance.
• Laboratory and testing equipment: clean, repeatable signal lines for calibration rigs, environmental chambers and quality control stations.

For complete temperature loops, we supply capillary lines alongside thermocouples, resistance temperature detectors, transmitters and thermocouple compensation wire so the entire path from process point to controller is covered by one order.

Quality Assurance and Acceptance

We implement quality supervision throughout the entire process, from incoming material to final testing. Our quality system is certified to GB/T 19001-2016/ISO9001:2015 and CE, and we hold national explosion-proof production qualification certificates for explosion-proof thermocouples and resistance temperature detectors.

• Material and dimensional consistency are checked during production, including surface condition and end preparation.
• Completed assemblies are checked for connection fit before packing.
• Our calibration laboratory uses high-precision equipment with calibration resolution up to 0.01 °C for instrument assemblies that require a certificate.
• Explosion-protected temperature sensors and RTDs can be supplied with the corresponding qualification documentation for hazardous-area projects.

Installation, Maintenance and Project Support

We support capillary tube installations as part of a complete measurement or control package. The same engineering team can design and install automatic temperature control boxes, temperature control rooms and remote monitoring temperature control systems for larger projects.

• Complete assemblies: capillary tube supplied with compression fittings, thermocouple heads, protective sleeves or instrument connectors.
• Spare parts: capillary tube and related accessories are kept in inventory for rapid replacement.
• Warranty: 12-month warranty covers non-human damage during normal use.
• Calibration service: for sensors and instruments that require periodic calibration, we provide professional calibration and calibration guidance.

Information We Use to Configure Your Solution

To prepare a precise capillary tube configuration and quotation, our engineers need the operating conditions and the interface details of the system. The most useful project inputs are:

• Instrument type and manufacturer: pressure gauge, pressure transmitter, thermocouple, RTD, controller or recorder.
• Process media, working temperature and maximum pressure at the sensing point.
• Required tube length, routing constraints, minimum bend radius and available mounting space.
• Connection style on both ends: thread size, compression fitting type, flare, or plain tube.
• Material requirements, cleaning procedure, and any chemical exposure or washdown conditions.
• Quantity, packaging preference and delivery destination.

With these details, we prepare a configuration drawing, bill of materials and quotation. For special specifications, we can develop the capillary tube from customer drawings or samples.

Frequently Asked Questions

Can you supply capillary tubes as part of a complete temperature or pressure assembly?

Yes. We supply capillary tubes alone or as part of a complete measurement loop. In the same order we can include thermocouples, RTDs, pressure gauges, transmitters, thermocouple heads, connectors and thermocouple compensation wire, so one supplier manages the full signal path.

What dimensions do you need to quote a capillary tube order?

We need the outside diameter, wall thickness or inside diameter, total length, and connection type on both ends. If the tubing size has not yet been fixed, we recommend a size based on the instrument connection and the system pressure and temperature.

How do you ensure a leak-free connection?

We match the end termination to the instrument fitting, confirm that the tube is cut and cleaned before assembly, and provide complete assemblies with the correct compression sleeves, nuts or threaded fittings. Final fit is checked before packing.

Do you support custom capillary tube specifications?

Yes. Customized production is our core business. We can manufacture normal and special specifications based on drawings or samples, and our technical development team and patent portfolio support non-standard interfaces, materials and assembly configurations.

What warranty and after-sales service do you offer?

All products supplied by Zhaolong Electrics are covered by a 12-month warranty for non-human damage. We also provide calibration service and spare parts supply, allowing replacement parts to be available when maintenance is needed.