Diaphragm Seal Services

Introducing Our New Low Volume Instrument Manifold (LVIM)

We’re excited to introduce our latest innovation for multi-instrument assemblies: the proprietary Low Volume Instrument Manifold (LVIM). Developed as a superior replacement for the outdated “Goal Post” configuration, the LVIM is ideal for setups where both instruments feature displays that require an upright position.

These manifolds are precision-machined from solid 316L stainless steel bar or hex stock. Their exceptionally small 0.156″ bores significantly reduce the overall fluid volume within the assembly. This innovative design minimizes temperature-induced measurement errors that can arise from the volumetric expansion of fill fluids, ensuring greater accuracy and reliability in your critical applications.

The LVIM is offered in both 1/4″ NPT and 1/2″ NPT connection sizes to suit your specific needs.

Prefabricated Piping Assemblies for Faster Installation

Colonial Instruments offers prefabricated piping assemblies designed to significantly reduce your field installation time. We can ship these assemblies either pre-attached to your diaphragm seal unit or separately, depending on your project needs. This service is particularly valuable in Waste Water and Water Treatment applications, where specifications often require units to come pre-assembled with their piping.

We provide a wide array of piping configurations for both flushing ports and off-process connections of the diaphragm seal. Our offerings include various connection sizes and shut-off valve specifications. The next time your drawing or specification calls for a “piping tree,” you’ll know exactly who to call.

Protect Your Instruments from Heat: Ensure Accurate Readings

Excessive heat is a common cause of inaccuracy in pressure gauges and transmitters. For example, most Bourdon tube pressure gauges exhibit an additional 0.4% error in span for every 18°F (10°C) above reference conditions (68°F / 20°C). This means if your instrument is operating at 200°F, you could be facing an additional 3% error in reading, on top of the manufacturer’s stated accuracy.

To maintain instrument accuracy in critical applications, it’s essential to use diaphragm seals combined with properly selected heat dissipating elements.

Colonial Instruments offers high-performance cooling solutions:

• The WIKA 4″ finned cooling element, rated up to 500°F (260°C).
• The WIKA 8″ perforated cooling element, rated up to 750°F (399°C).

Both are available with 1/4″ NPT and 1/2″ NPT connections. For particularly aggressive and critical applications where fugitive emissions are a concern, we can also provide these elements welded directly to the diaphragm seal’s upper housing, ensuring maximum integrity and performance.

Capillary Assemblies: Remote Mounting, Level Measurement & Heat Protection

Capillary assemblies offer versatile solutions for instrument applications, enabling remote mounting, precise level measurement in DP applications, and effective instrument protection from excessive heat.

Selecting the ideal capillary assembly requires careful consideration of numerous variables. Beyond standard factors like length, connection sizes, and capillary material, critical considerations include:

• Capillary internal diameter
• Proper fill fluid selection
• Calibration offset for positive or negative head pressure
• And many more technical details.

Don’t let the complexity be a burden. Let Colonial Instruments do the heavy lifting. Simply provide us with some basic process details, and our experts will handle the rest, ensuring you receive the perfect capillary assembly for your needs.

Essential Diaphragm Seal Accessories: Enhancing Performance and Protection

The categories discussed above are essential accessories for diaphragm seals, designed to enhance performance, protect your valuable instruments, and ensure consistently accurate readings.

Beyond the options previously detailed, here are some additional accessories you might consider:

• Snubber: A simple yet effective solution, a porous disc or piston snubber is ideal for protecting your instrument from pulsation and achieving more stable readings.
• Pressure Limiting Valve (PLV): This self-operating shut-off valve can be set to a specific pressure, automatically shutting off pressure to the instrument and safeguarding it from overpressure damage. PLVs work exceptionally well when paired with a snubber, as the snubber provides additional time for the PLV to react to sudden pressure spikes.
• Lockwire: This straightforward wire attachment between the instrument and diaphragm seal acts as a deterrent, preventing operators from removing or turning the instrument in the field. This helps to avoid compromising the fill of the sealed system.
• Flushing Ring: Designed for use with flanged diaphragm seals, a flushing ring is a wafer-style device that fits between specific-sized flanges, sitting beneath the diaphragm seal. It can be machined with one or more flushing or test ports. These are typically employed with viscous process media or where particulates are present, requiring periodic back-flushing. Another valuable application is using the flush ring as an access point for external calibration.

These accessories collectively contribute to the longevity, reliability, and accuracy of your instrumentation in demanding applications.

Comprehensive Submittal Packages for Your Projects

At Colonial Instruments, we provide detailed submittal packages upon request, just like the example pictured above. Each package is tailored to your project, featuring a submittal cover customized with your pertinent company information, including your name, phone, and email.

For diaphragm seal assemblies, our submittal includes a comprehensive “shop sketch,” clearly identified by a unique sketch number. This number is also referenced by line item on the cover section, ensuring easy cross-referencing. If your project involves multiple sketches, this system allows you and your client to quickly and easily locate and reference all associated drawings for each item.