Product catalogue
Strain-gauge melt pressure instrumentation for plastics extrusion, compounding and moulding. Standard, mercury-free, NaK and FDA oil fills. Ranges from 300 to 30,000 psi. Inconel diaphragm as standard, not as an upgrade.
How to read a Meltman part number
Pressure code × unit multiplier = range. P 5 = 5,000 psi · B 3 = 300 bar. Thread and option codes are appended after the diaphragm code, each separated by a hyphen; a blank position means the standard. Fill and body are independent — any of the four fills can be supplied in any of the five body types, with any output.
Choosing a fill
| Code | Fill | Max diaphragm temp | Mercury free | Specify when |
|---|---|---|---|---|
| GG | Standard, fluid filled | 750°F (400°C) | No | General extrusion, compounding and moulding |
| MF | Mercury free | 750°F (400°C) | Yes | Plant policy, customer requirement or market regulation excludes mercury |
| NF | NaK | 1000°F (538°C) | Yes | High-temperature engineering polymers; food, medical and pharmaceutical processes |
| OF | Diathermic oil, FDA | 650°F (350°C) | Yes | Lower-temperature processes where FDA approval of the fill is the governing requirement |
Fill & ceiling
All five body types are available in every fill — GG, MF, NF and OF — and with every output, from 3.3 mV/V transducers to 4–20 mA and voltage-output transmitters. Drawings are representative and not to scale.
Housing sits directly at the mounting point. Simplest to install, lowest cost, and correct wherever there is room for it and the electronics are not in a hot spot.
Armoured flexible capillary moves the housing away from the machine. Two reasons to choose it: the electronics sit somewhere cooler, and the connector can be positioned where a cable can actually be routed.
A temperature sensor mounted directly behind the pressure diaphragm gives both readings from a single mounting hole. It is field replaceable without removing the pressure sensor, which matters because thermocouples fail more often than diaphragms do.
Die faces, adapter blocks and screen changers are crowded, and “there is no room for the sensor” is a common reason a measurement point goes unmonitored. NS removes the rigid stem entirely: a thin bare capillary threads through whatever space exists before meeting the armoured section.
A shortened body for installations where axial clearance behind the mounting point is the constraint rather than radial space. Same diaphragm, same bridge, same fills.
How the sensor works
A melt pressure sensor does not measure pressure where you read it. Process pressure deflects a thin diaphragm at the tip. A sealed, fluid-filled capillary transmits that deflection to a second diaphragm inside the housing, several inches away and much cooler, where a four-active-arm 350 Ω Wheatstone bridge converts it to a millivolt signal proportional to pressure. An internal shunt calibration resistor lets you verify sensor and instrument agree at 80% of full scale without a pressure source. The fluid in that capillary is what the fill code selects, and it governs the temperature the sensor will survive.
Diaphragm selection
| Code | Material | Specify for |
|---|---|---|
| SI | Standard Inconel | General purpose. Fitted as standard, not charged as an upgrade — the tip is where these sensors fail, so that is where the material belongs |
| IT | Inconel tip + threads | Where the thread as well as the tip is exposed to melt |
| HT | Hastelloy tip + threads | Corrosive melts — PVC, halogenated and fluoropolymers |
| TN | Titanium nitride | Abrasive melts — glass-filled and mineral-filled compounds |
| TA | Titanium aluminium nitride | Abrasive melts at higher temperature |
| CN | Chromium nitride | Alternative hard coating for abrasive service |
| DP | Diamond particulite | Extreme abrasion — heavily filled compounds, contaminated regrind |
Worked examples
| Part number | Reads as |
|---|---|
| GGRS2-AP5-6BSI | Standard fill, rigid stem 6″, 3.3 mV/V, 0–5,000 psi, 6-pin bayonet, standard Inconel, 1/2″-20 UNF |
| GGFS1-CP10-6BSI | Standard fill, stem + flex 6″+18″, 4–20 mA transmitter, 0–10,000 psi, 6-pin bayonet, standard Inconel |
| NFPT1-AP10-6BIT-TK | NaK fill, pressure + temperature, 6″+18″, 3.3 mV/V, 0–10,000 psi, 6-pin bayonet, Inconel tip and threads, thermocouple K |
| MFNSC-AP5-6BHT-18 | Mercury-free fill, narrow space, 10″ capillary + 18″ flex, 3.3 mV/V, 0–5,000 psi, 6-pin bayonet, Hastelloy tip and threads, M18×1.5 |
| OFRS2-AB3-6BSI-25 | FDA oil fill, rigid stem 6″, 3.3 mV/V, 0–300 bar, 6-pin bayonet, standard Inconel, 0.25% accuracy |
Cables & connectors
| Jacket | Rating | Specify when |
|---|---|---|
| PVC | 105°C | Routed away from the barrel, no mechanical exposure |
| PTFE | 200°C | Close to heated zones, oils or solvents present |
| PTFE + SS braid | 200°C | Abrasion, or where the cable is handled often |
| PTFE + SS armour | 200°C | Crush risk — trays, walkways, trolley routes |
Standard lengths 12, 25 and 50 ft. Cable-end and box-end connectors for every termination we supply. Thermocouple extensions in type J and K.
Mounting & hole preparation
| Item | Detail |
|---|---|
| Hole cut kits | 1/2″-20 UNF · M18×1.5 · 5/8″-11 · 3/4″-16 |
| Hole clean kits | Same thread sizes |
| Tip spacers | 0.025 · 0.032 · 0.045 · 0.063 · 0.090″ |
| Hole plugs | Slot · 3″ hex · 6″ hex |
| Thread adaptors | M18 → 1/2″-20 UNF |
| Mounting brackets | All flex-stem builds |
Technical notes
Cross-reference
Warranty & support
| Warranty | One year against manufacturing defects |
| Support | Every enquiry is read by someone who understands the products |
| Hours | Monday to Saturday, business hours IST |
Contact
| Address | Focal Point Phase V, Ludhiana, Punjab, India |
| meltmansales@gmail.com | |
| Telephone | +91 9779722477 |