Sunday, September 30, 2018

Piping Specialties / PSI Controls: New England's Preferred Source for Industrial Valves, Valve Automation, and Process Instrumentation

Founded in 1975, with offices in Portland, Maine and Danvers, Massachusetts, PSI has earned their reputation as New England's premier supplier of industrial valves, valve automation, process instrumentation and specialty process equipment.

PSI specializes in engineered products for these industries:

  • Power Generation
  • Pulp & Paper
  • LNG / LPG / Natural Gas / Gas Storage & Distribution
  • Pharmaceutical / BioTech
  • Food and Beverage
  • HVAC
  • Water & Wastewater

Piping Specialties, Inc / PSI Controls
https://psi-team.com
800-223-1468

Wednesday, September 26, 2018

Top 5 Considerations in Selecting Pressure Gauges

Pressure gauges are ubiquitous in industry and installed on machinery around the world. While there are millions of possible combinations of shapes, sizes, options and materials, careful attention needs to be given to the following five criteria for safe use and long product life.

1) Process Media
Direct exposure of the sensing element to the process media is a possibility, so attention must be given to any corrosive media, media with particulate, or media that can solidify and clog the pressure gauge element. For non-clogging media, a direct connection and Bourdon tube sensor can be applied. For process media that could potentially cause clogging, a diaphragm seal should be used.

2) Process Media Temperature
Gauge with diaphragm seal
Gauge with
diaphragm seal.
(AMETEKUS Gauge)
Very hot media, such as steam or hot water, can elevate the gauge's internal temperature leading to failure or an unsafe condition. For high temperature application, the use of a gauge "siphon" or diaphragm seal be applied.

3) Ambient Operating Temperature and Environment
It is important to know the rated ambient environment for any instrument. Elevated ambient temperatures, moisture, vibration, and corrosive atmospheres can all affect accuracy, calibration, and safety. Choose the proper case and mechanism materials if oxidizing or reducing atmospheres exist, and consider the addition of ancillary devices, such as remote diaphragm seals, to relocate the gauge.

4) Possibility of Severe Pressure Fluctuations
In applications where dramatic line pulsations or strong over-pressure conditions are a possibility the use of pressure restrictors, snubbers, or liquid-filling will extend the service life of the pressure gauge.

5) Mounting
Snubbers & restrictors
Snubbers & restrictors

Pressure gauges are standardly available with bottom (radial) and back connections. NPT (National Pipe Thread Taper) threaded connections are generally the standard. Many other process connections are available though, such as straight threads, metric threads, and specialized fittings. Make sure you know how the gauge is being connected. When mounting, pressure gauges should be almost always be mounted upright.

For more information about pressure gauges, contact PSI Controls by visiting https://psi-team.com or by calling 800-223-1468.

Monday, September 17, 2018

What is an External Spring, Lever & Weight Single Disc Check Valve

Check valve animation
Single disk check valve animation.
According to Wikipedia, "Check valves are used in many fluid systems such as those in chemical and power plants, and in many other industrial processes."

Check valve symbol
Check valve symbol
As shown in the animation to the left, the single disc (swing) check valve use the directional flow to push open a swinging disk. As long as flow continues, the disk stays raised. But as flow stops, gravity allows the disk to re-seat itself and any reverse flow is prevented by the closed disk. As reverse flow pressure increases, the swing check valves seating increases as well.

Single disc check valves also use springs, levers and/or weights mounted on the valve to allow for better control of surge and to prevent the valve from slamming closed. These assemblies are used to vary the valve’s closing operation in order to reduce the severity of the closing water hammer.

spring, level and weight assisted check valve
External spring, external spring & lever, and external spring, level & weight designs (left to right).
Courtesy of Champion Valve.
For more information on any industrial check valve, contact Piping Specialties, Inc. by visiting https://psi-team.com or calling 800-223-1468.