Pressure Gauges — Reliable Pressure Measurement for Process & Utilities
Accurate pressure measurement is fundamental to safe plant operation, process control, leak detection and regulatory compliance. At NPK Industries, we supply a wide range of mechanical and process pressure gauges from trusted brands — Baumer and GIC — suitable for industrial, hygienic, and utility applications. Our offerings include standard bourdon tube gauges, diaphragm gauges, capsule and differential gauges, specialised sanitary designs and high-accuracy variants for critical loops.
What is a Pressure Gauge?
A pressure gauge is an instrument that converts process pressure (liquid or gas) into a readable mechanical or electrical output. Mechanical gauges (bourdon, diaphragm, capsule) use elastic elements which deform under pressure; this deformation is transmitted via gearing to a pointer on a dial. Modern gauges may include integrated transmitters offering 4–20 mA / HART outputs for SCADA/PLC integration.
Working Principles — Key Types
1. Bourdon Tube Gauge (Common mechanical type)
- Principle: A C-shaped (or helical) flattened tube tends to straighten when internal pressure increases. This elastic deformation is transmitted by a linkage-and-gear to a pointer.
- Use: General process pressure, steam, water, hydraulic systems.
- Advantages: Robust, simple, no power needed, wide ranges (vacuum to high pressure).
2. Diaphragm Gauge
- Principle: A flexible diaphragm deflects under differential pressure; the deflection is amplified mechanically or electronically.
- Use: Low-pressure measurement, corrosive fluids (with isolated diaphragm), hygienic processes.
- Advantages: Better for very low pressures and for abrasive or viscous fluids when used with seals.
3. Capsule Gauge
- Principle: Two corrugated diaphragms (capsule) expand/contract with pressure differences. Movement is linked to the pointer mechanism.
- Use: Low-pressure compressed air, HVAC, gas metering.
- Advantages: Compact, good low-end sensitivity.
4. Differential Pressure Gauges (DP)
- Principle: Measure the difference between two pressure ports (useful for filter monitoring, flow via orifice/venturi).
- Use: Filter condition, pump head, flow measurement systems.
- Advantages: Direct visual of differential; can be used with transmitters.
Baumer vs GIC — Brand & Model Overview
- Baumer (AVF, ALF, AFF, ATD, ATC, AXF) — strengths & typical use
- AVF / AFF — Robust industrial bourdon gauges, wide ranges, glycerin-filled options for vibration/ pulsation damping.
- ALF — Compact sanitary/hygienic gauges with tri-clamp/flanged options — commonly used in dairy, food & pharma.
- ATD / ATC — Diaphragm & capsule variants for low-pressure and corrosive media; sanitary options available.
- AXF — High-accuracy, capsule/differential models for instrumentation panels and calibration use.
Baumer strengths: High build quality, comprehensive hygienic options, strong European manufacturing standards, good availability of sanitary materials (SS316L), and advanced design for damped movement (suitable for pulsating fluids).
GIC — BSPG Series (Bourdon / Panel Gauges) — strengths & typical use
- BSPG — General purpose bourdon tube gauges in robust housings; often cost-effective with reliable accuracy classes for industrial applications.
GIC strengths: Competitive pricing, straightforward and rugged construction for heavy industrial use, rapid delivery for standard ranges, and simple interchangeability for maintenance.