Quick Guide to Choosing Pressure Gauge Shock Absorbers

ZAES launches technical guide to help engineers and operators choose the right pressure gauge snubber for each industrial application

One of the most frequent problems in industrial instrumentation is pressure gauge instability caused by pulsations, vibrations, pressure peaks and pressure surges. These disturbances not only make correct reading difficult, but also lead to premature wear and failure of the instrument. To solve this challenge, ZAES presents a specially designed technical guide to select the right pressure snubber according to the type of process, fluid and pulsation level..

In this guide, ZAES combines its expertise in industrial instrumentation with good engineering practices and selection criteria used in steam plants, chemical processes, hydraulic networks and gas systems.

What is a pressure gauge shock absorber and why should you choose the right one?

Pressure gauge dampers - or gauge snubbers- are devices designed to regulate or restrict the pressure flow to the instrument, This prevents it from directly receiving the pulsating waves or hydraulic shocks generated by the process.

An incorrect shock absorber can:

• transmit too many pulses,
• block the measurement,
• not enough cushioning,
• generate excessive reading delays,
• deteriorate rapidly,
• or even damage the pressure gauge.

For this reason, choosing the right type is essential to ensure stability, accuracy and a longer instrument lifetime..

Key parameters for selecting the right ZAES shock absorber

ZAES identifies a number of technical criteria that should be evaluated before selecting a shock absorber. This guide summarises the most important ones so that engineers and operators can make the right decisions.

1. Type of process fluid

The behaviour of the fluid directly influences the type of shock absorber required.

✓ Clean fluids (water, air, gas, regulated steam)

A standard shock absorber with fixed restriction can be used.

✓ Viscous fluids (oils, fats, greases, glycols)

They require a wider calibrated orifice to avoid clogging.

✓ Dirty or particulate fluids

A shock absorber with porous disc or sintered mesh to avoid blockages.

✓ Corrosive fluids

It is essential to use stainless steel AISI 316, resistant to chemical agents.

2. Level of pulsations or pressure shocks

ZAES dampers are classified according to the level of aggressiveness of the process.

✓ Low pulsation

Pneumatic processes, compressed air systems, moderate pressures.
→ Standard shock absorber.

✓ Medium pulsation

Centrifugal pumps, light machinery, water networks.
→ Shock absorber with medium restriction.

✓ High pulsation

Reciprocating pumps, hydraulic presses, piston compressors.
→ Reinforced or sintered shock absorber.

✓ Violent water hammer

Processes with abrupt valve closures, instantaneous start-ups or flow changes.
→ Special shock absorber with fine calibration.

3. Working pressure range

It is essential to select a snubber that can withstand the pressure range of the process:

• Low pressure < 16 bar
• Medium pressure 16-100 bar
• High pressure 100-400 bar
• Very high pressure > 400 bar

ZAES offers specific dampers for each range, avoiding deformations or failures due to overpressure.

4. Fluid temperature

Although the shock absorber protects against pulsation, it does not protect against extreme heat.
In steam or hot fluid processes, ZAES recommends a combination:

• Pressure cushioning
• + Siphon tube

This combination is ideal for:

• saturated vapour,
• superheated steam,
• thermal oil,
• industrial furnaces.

5. Shock absorber material

Depending on the fluid and the environment:

Carbon steel

• Water
• Air
• Pneumatics
• Standard hydraulics

Stainless steel AISI 316

• Steam
• Chemical products
• Food and beverages
• Corrosive environments
• Sanitary applications

6. Connection type: BSP or NPT

ZAES offers threaded dampers:

• BSP (G) for European installations,
• NPT for American systems and imported machinery.

Choosing the right connection avoids leaks and compatibility problems.

Types of ZAES buffers and their ideal applications

ZAES summarises its technical guide by classifying its shock absorbers into three main groups according to application:

1. Calibrated orifice dampers

They allow a fixed restriction adapted to medium pulsations.
Applications:

• industrial water
• compressed air
• distribution lines
• pneumatic systems

2. Shock absorbers with sintered (porous) discs

Often called “sintered dampers”.
Ideal for:

• dirty fluids,
• particulate processes,
• viscous oils,
• compressors,
• heavy hydraulics.

Its porous structure acts as a filter and pressure regulator.

3. Reinforced water hammer dampers

Designed for processes with extreme mechanical aggressiveness:

• turbines,
• alternative pumps,
• hydraulic presses,
• dry starts,
• sudden changes in flow,
• quick-closing valves.

These models guarantee maximum reading stability.

Installation recommendations according to the ZAES guide

A shock absorber is most effective when it is installed correctly.
The guide advises:

• mount the damper directly on the pressure gauge inlet,

to absorb pulses before they reach the instrument.

• combined with pressure gauge valve,

to purge the line before start-up.

• maintain the correct orientation,

avoiding mechanical stresses or twisting of the thread.

• use suitable sealants,

as industrial grade PTFE tape.

Operational benefits of choosing the right shock absorber

A well-chosen shock absorber offers advantages that directly impact productivity:

1. Stable and accurate readings

The needle remains still even in dynamic processes.

2. Fewer breakdowns

The Bourdon tube suffers less mechanical fatigue.

3. Reduced maintenance

Fewer replacements, fewer recalibrations.

4. Increased service life of the pressure gauge

It can be multiplied by 3, 4 or up to 6 times.

5. Increased operational security

The likelihood of instrument breakage under intense pulsation is minimised.

In a nutshell: A practical guide to selecting the right shock absorber

The ZAES Technical Guide for choosing pressure gauge dampers becomes an essential tool for engineers, industrial mechanics, operators and maintenance managers.
With this publication, ZAES reinforces its commitment to:

• industrial safety,
• measurement accuracy,
• reduction of maintenance costs,
• and reliability in instrumentation.

A shock absorber is not just an accessory: it is a key part in ensuring the stability of the system and prolonging the life of the pressure gauge.