Strain gauge pressure transducer K3

piezoresistiveratiometricvoltage output

Overview
The K3 series by Gefran are melt pressure sensors designed for high-temperature process applications (up to 538°C / 1000°F depending on diaphragm material). Hydraulic pressure transmission is achieved using a near‑incompressible sodium‑potassium (NaK) fill, enabling stable pressure measurement at hot measurement points while the sensing element operates in a temperature-protected area. Output is delivered as an mV/V signal suitable for integration into acquisition systems.

Main features

• Pressure ranges: 0–35 to 0–1000 bar (equivalent 0–500 to 0–15000 psi).
• Output signal: mV/V (typical options 2–2.5 mV/V or 3–3.33 mV/V).
• Accuracy classes: < ±0.25% FS (H) and < ±0.5% FS (M).
• Hydraulic transmission fluid: sodium‑potassium (NaK) mixture; near‑incompressible; RoHS conformity; NaK defined as GRAS by FDA for applicable configurations.
• Diaphragm coatings and high‑temperature options available (GTP+ coating examples).

Applications

• High‑temperature melt pressure measurement in polymer processing and extrusion lines.
• Configurations suitable for mercury‑free, food and medical related processes when appropriate certification and configuration are selected.
• Processes requiring stable pressure signal at elevated process temperatures.

Technical specifications

• Output options: 2–2.5 mV/V or 3–3.33 mV/V.
• Pressure ranges: examples include 35, 50, 70, 100, 200, 350, 500, 700, 1000 bar (psi equivalents up to 15000 psi).
• Accuracy: < ±0.25% FS (H); < ±0.5% FS (M).
• NaK fill volumes (examples): K30 series ≈ 30 mm³; K31/K32/K33 ≈ 40 mm³.
• Standard mechanical threads: 1/2-20 UNF and M18x1.5; other threads on request.
• Diaphragm materials and max temperature (examples): Inconel 718 with GTP+ — up to 538°C (1000°F); 15‑5 PH with GTP+ — up to 400°C (750°F); Hastelloy C276 — up to 300°C (570°F); 17‑7 PH corrugated with GTP+ for ranges below 100 bar.
• Mechanical configurations: rigid stem, rigid+flexible stem, versions with thermocouple, exposed capillary.
• Rigid stem length examples: 38 mm, 50 mm, 76 mm, 153 mm, 318 mm; extended lengths available per configuration.
• Connector options: 6‑pin and 8‑pin connectors.
• Optional accessories: extension cables, mounting/cleaning kits, rupture disks, CAD/3D models and documentation.