SERIES-385H

Supported Applications

The Omega Series 385H is a heavy-duty threaded thermowell designed for temperature-sensing elements with a maximum diameter of 0.377". The series accommodates standard length, ¼" stem bimetal thermometers, #14-gage thermocouple test elements, and armored liquid-in-glass test thermometers. It supports other temperature-sensing elements having the specified maximum diameter.

Documented applications include environments requiring corrosion resistance and chemical baths. The series is compatible with OMEGA® NB1, NB2; PR-12, PR-14, and NPT-style probes, as well as DialTemp™ Thermometers.

Operating Conditions & Performance

The Series 385H features a shank diameter of 1/16". Insertion lengths (U) range from 2½" to 22½", with corresponding stem lengths (A) ranging from 4" to 24".

Pressure ratings vary by material and temperature, expressed in lb per square inch (psi). The documented pressure-temperature limits are:

• Brass: 5000 psi at 70°, 4200 psi at 200°, 1000 psi at 400°.
• Carbon Steel (C-1018): 5200 psi at 70°, 5000 psi at 200°, 4800 psi at 400°, 4600 psi at 600°, 3500 psi at 800°, 1500 psi at 1000°.
• A.I.S.I. 304: 7000 psi at 70°, 6200 psi at 200°, 5600 psi at 400°, 5400 psi at 600°, 5200 psi at 800°, 4500 psi at 1000°, 1650 psi at 1200°.
• A.I.S.I. 316: 7000 psi at 70°, 7000 psi at 200°, 6400 psi at 400°, 6200 psi at 600°, 6100 psi at 800°, 5100 psi at 1000°, 2500 psi at 1200°.
• Monel®: 6500 psi at 70°, 6000 psi at 200°, 5400 psi at 400°, 5300 psi at 600°, 5200 psi at 800°, 1500 psi at 1000°.

Maximum fluid velocity limits are referenced on Page B-25 of the source documentation. To increase response rate, OT-201 Conductive Silicon Paste is noted as an option (see omega.com).

Configuration Options

The series offers configurable wetted materials and protective coatings to suit specific process requirements.

• Wetted Materials: Brass (ASTM B-16), Carbon Steel (C-1018), Stainless Steel A.I.S.I. 304, Stainless Steel A.I.S.I. 316, and Monel®.
• Protective Coatings: PFA coating is available; Epoxy coatings are also offered. Consult the Sales Department for other materials or specific coating details.
• Process Connections: Standard external thread "P" is 1 NPT. Other thread sizes are available upon request. A note indicates that † NPSM internal pipe thread will accept both NPT and NPS male threads.

Key Product Differences

Variants differ by insertion length, stem length, and material selection. The model number format is 1-385H-<U><A>/<P>-<MATERIAL>. Material suffixes include "304SS" for A.I.S.I. 304 stainless steel, "316SS" for A.I.S.I. 316 stainless steel, "CS" for carbon steel, and "BRASS" for brass.

Optional accessories include a Brass Plug & Chain. Cap and chain options are available with suffixes: add "-CC-Brass" for a Brass cap or "-CC" for a 304 SS cap (additional cost). Metric models are noted as available on omega.com.