Category Archives: Garlock

Water Regulations and NSF 61 Compliant Elastomers

Replacing Aging Water Infrastructure With NSF Compliant Materials

There are over 155,000 public water systems in the United States and more than 286 million Americans who rely on community water systems daily.  Since most of the infrastructure was built between the early 1900’s and 1960 using outdated technology/products and capabilities, nearly everything is approaching the natural end of it’s lifespan.

Some estimates put the repairs and replacement of thePicture of NSF Compliant Gaskets infrastructure between $250B and $500B over the next 20-30 years. Several applications will need to be updated or fully replaced for the safety of consumers and quality of delivery, including:

  • Joining and sealing materials
  • Mechanical devices
  • Pipes or related products
  • Process media
  • Plumbing devices
  • Non-metallic potable water materials
  • Hydrants
  • and Public drinking water distribution (tanks and reservoirs, maters, individual components)

Joining and Sealing Materials

When these systems were being constructed and assembled decades ago, there were limited regulations and requirements that needed to be met. Gaskets, at least the traditional ones, were often made in two different ways: (1) Red Rubber (ASTM D1330 Grade 1 &2) with compressed non-asbestos or (2) cloth-inserted rubber with compressed asbestos.

However, today’s acceptable gasket requirements for the potable water industry differ greatly from those in the past. Gaskets have strict guidelines to abide by and must be:

  • Chemically resistant
  • NSF compliant
  • Food grade compliant
  • Electrically isolating

Because of the need for health and safety, the National Sanitation Foundation (NSF) was created in order to establish minimum requirements for the control of potential adverse human health effects from products that contact drinking water. In addition to gaskets, the NSF covers a variety of products and parts relevant to the water industry, including: pipes, hoses, fittings, cements, coatings, gaskets, adhesives, lubricants, media, water meters, valves, filters, faucets, fountains, and more.

So you might ask – why does the NSF require different materials and regulations for gaskets compared to years ago?

First things first – leaks are a major issue with the aging infrastructure. Improperly placed gaskets & seals or faulty products can cause leaks. This in turn could pose health risks to people drinking potable water or using products processed with potable water.

Additionally, the treatment process and chemicals utilized are Picture of NSF 61 Compliant Sealsdifferent from previous “standard” products. For example, research and testing over many years has concluded that traditional gaskets, which were used many years ago, could pose a safety threat to those drinking water processed with specific materials. This led to updated regulations for NSF 61’s drinking water system components.

Lastly, engineered sealing solutions are more important than ever. There’s a wide variety of custom engineered water systems throughout the U.S. – climate, geographic terrain, and the needs of the community are all reasons for why water infrastructure is so unique. Because of this, custom gaskets, seals, and other products are needed to supplement those systems.

Luckily there are many companies dedicated to providing the highest quality NSF 61 products. These trusted brands have proven materials to count-on when replacing or repairing water infrastructure:

Garlock’s NSF 61 Family of products

Parker’s NSF compliant products

Freudenberg’s new generation of NSF products

For more information on how Gallagher Fluid Seals’s engineers can help you with a custom solution, call us at 800.822.4063

A User’s Guide to Expansion Joint Control Units

Expansion Joint Control Units

Elongation settings are a vital factor to assembly effectiveness.

Diagram of Control Unit and Control Rod Components

It is no secret that one of the greatest demands for an expansion joint is the expectation to serve a long, leak-free life with little-to-no maintenance. Once installed, these flexible rubber connectors should require little attention. The preservation of this investment (and one’s sanity) can be maximized with an in-depth overview of how control units can prevent a new expansion joint from being overstressed.

The purpose of a control unit is to act as a safety device against excessive movement resulting from pressure thrust. A typical control unit assembly is comprised of threaded rods, steel gusset plates, nuts and washers (see Images 1 and 2).Diagram of Effects of Pressure Thrust

The usage of control units with an expansion joint is always beneficial; pressure spikes during a system upset can cause uncontrolled surges through the expansion joint. This is a prime example of how valuable it is to have control units installed to protect these rubber assets from damage.

Methods to the Madness

A common misconception about control units  is that they are designed to support the weight of pipe members or act as a substitute for adequate mounting. They are not. The sole purpose of a control unit is to allow the expansion joint to move freely within a specific range of movement while preventing the joint from being overstretched from pressure thrust forces.

The control units in no way impede the joint from performing its other duties beyond movement  (vibration absorption, cycling or compensation for misalignment). The few extra steps needed to install the control units with the expansion joint could pay notable dividends in the long run.

Pressure thrust plays a huge role in how an expansion joint functions. While under pressure, the forces acting on the inside walls of the expansion joint actually cause the joint to swell and elongate. In the real world, an expansion joint is held comfortably between two pipe flanges, which in most cases are restrained by a pump lagged to the floor or mounted to a structural beam. Although it may not be apparent to the naked eye, once the expansion joint sees pressure, it produces a thrust force that acts axially on both pipe flanges.

Theoretically, what would be the result if the expansion joint was unrestrained on each end while pressurized?

Without fixed ends, the pressure thrust would force the joint to elongate without bounds.

Most useful in high pressure applications, the control rods will  engage with the gusset plates once a pre-specified amount of growth for the expansion joint has been reached, restricting the joint from stretching any further. At this point, the control rods are absorbing any additional thrust  acting on the pipe flange, thus limiting the amount of stress that is exerted onto adjoining equipment.

The design theory for sizing control unit hardware is based on the pressure thrust. Nominal inside diameter (ID) and arch geometry of the expansion joint are key drivers for calculating the thrust force that will be applied to the pipe at maximum line pressure. Per

Arch Diameter Diagram

industry standards set by the Fluid Sealing Association (FSA), both control rods and gusset plates are designed to withstand no more than 65 percent of the yield strength of the material.

Magnitude of the pressure thrust can be calculated by knowing the internal pressure and the effective area of the expansion joint. Effective area is found using the arch diameter of the expansion joint, which takes into account the size of the arch.

For example, we can calculate the resulting pressure thrust for a 10-inch ID expansion joint using an arch height of 1.5 inches that is rated for a maximum pressure of 250 pounds per square inch (psi).

The equation for pressure thrust “T” is:

Equation for pressure thrust

These design limitations based around yield stress are the reasons why some control units made from lower yield strength stainless steel contain thicker components or more rods per set than the standard carbon steel control units.

Installation & Inspection

For a control unit assembly to be effective, rod positioning and elongation settings are critical during installation. Each control rod should be evenly spaced around the flange to best distribute the load. Elongation settings (see Image 5) are often overlooked, yet are a vital factor to ensure the control units fulfill their intended use.

Every expansion joint comes with movement ratings based on arch size, configuration and number. These movement design ratings of the expansion joint are critical pieces of information that are absolutely required during the installation of control units. The general rule of thumb is the gap between the gusset plate and the nut should be adjusted to match the joint’s elongation rating.

Having this information at hand during installation is great, but what about the existing control units currently in operation? Visual inspections of these components are a basic task that goes a long way toward extending the life of the joint.

Here are the top 4 anomalies to look for when performing a field inspection: Continue reading A User’s Guide to Expansion Joint Control Units

The Rise of Metal Detectable O-Rings

Food Safety Modernization Act (FSMA)

Every year, nearly 1 in 6 people in the U.S. get sick (~48 million people), 100,000+ are hospitalized, and 3,000 die from foodborne illnesses or diseases, according to data from the CDC. Though this is largely a preventable problem, it still poses a significant public health burden.

The FDA Food Safety Modernization Act (FSMA), enacted by Congress in 2011, is “transforming the nation’s food safety system by shifting the focus from responding to foodborne illness to preventing it.”

Although one might think the relevancy of the FSMA isPastries on a Conveyor Belt more geared towards the food or beverage product itself, this act is actually vital to the processing operations in food, beverage, and pharmaceutical industry.

Over time, exposure to continuous vibration, volatile temperatures, and corrosive chemicals can cause O-rings in processing operations to become worn and eventually fail. When this occurs, particles of rubber from seals and gaskets can shear-off and migrate through sanitary systems, piping mechanisms, or by other means, eventually entering the product stream.

In some cases when a problem is discovered, equipment must be shut down and visual inspections conducted to find the source of contamination. This leads to downtime, lost production, and lost revenue. If the contaminant ends up in the supply chain, even more risk is assumed due to recalls or litigation.

Enter the metal detectable O-ring.

Continue reading The Rise of Metal Detectable O-Rings

How to Investigate Compression Packing Failure Modes

Over-tightening, excessive speed and improper installation can cause a system to falter.

In many respects, troubleshooting and failure analysis of compression packing materials is similar to the investigation of a crime scene. A good investigator knows how to gather clues from many different sources and put them together to understand what has happened. A good troubleshooter uses the same information gathering method, familiarizing themselves with the sealing materials, the process equipment and the systems where they are used.

Start by Interviewing Witnesses

The troubleshooter should seek information from the people who work with the equipment on a regular basis. Seal installers, maintenance personnel, operators, process engineers and others can all shed light on potential causes of failure. Some key questions should be:

  • How is failure defined? Some examples include excessive leakage, overheating, high rate of flush water consumption, excessive friction load and blowout.
  • Is this application the source of chronic seal failures, or was this an unexpected event?
  • Were there any changes to the seal material, the equipment or the overall process that preceded the failure?
  • Were there any system upsets or cleaning cycles that preceded the failure?
  • Can you describe the installation procedure?

Gather Information About the Victim

Knowing the limitations of the sealing product is a key step. The acronym “STAMPS” will help remember the key elements to ensure the right packing is selected for the application.

  • S: Size. Is the correct packing cross-section being used? Are the rings cut or formed to the correct length?
  • T: Temperature. Check the system temperature against the packing manufacturer’s established temperature ratings for the product.
  • A: Application. Some packings are made specifically for rotary equipment while others are intended for valves or static seals. Check to make sure the packing is suitable for the equipment where it is being used.
  • M: Media. This refers to the fluid being sealed. Check with the manufacturer or with compatibility charts to be sure the seal material is compatible with the media. If the media is slurry, abrasion-resistant materials may need to be specified. If the media is toxic, explosive or required to be contained within certain maximum allowable leakage requirements, then a packing must also be selected on the basis of its ability to seal at low leakage levels.
  • P: Pressure. Check the system pressure against the packing manufacturer’s established pressure ratings for the product.
  • S: Speed. Check the equipment speed against the packing manufacturer’s established surface speed ratings for the product. Surface speed is expressed in feet per minute or meters per second and not revolutions per minute.

Investigate the Crime Scene

When possible, observe the equipment while it is running. Can you see, hear, feel, smell or use a sensor to make observations? Smoke, vibration, grinding noises, the scent of burning fibers and system pressure fluctuations are only a few of the clues that can be noticed or measured while the equipment is up and running.

Examine the condition of the equipment. Most packings are robust seals that can handle less than perfect equipment condition, but there are limits to the amount of degradation they can withstand.

Valve stems and pump shafts or sleeves should be checked for scratches, corrosion pitting and general surface roughness. Rough surfaces can damage the sealing surface and result in excessive leakage and quick wear of the seal.

Extrusion of the seal material
Image 1. Extrusion of the seal material

Excessive clearances at the top or bottom of the stuffing box can lead to extrusion of the seal material and intrusion of large solid particle into the seal area (see image 1).

In severe cases, excessive clearance may result in a seal blowout.

Most packings are not meant to function as both a seal and a bearing. In rotating equipment, poor bearing condition may result in shaft runout that “wallows out” the inside diameter of the seal. Misalignment may result in shaft/stuffing box offset that causes one side of the packing set to be heavily compressed while the other side is compressed much more lightly. A similar side loading of a packing set can occur in large horizontally oriented valves where the packing is forced to bear the weight of the stem.

Check to make sure all the parts are in place. During the breakdown, repair and reassembly of equipment it is possible to misplace parts. Equipment might be put back into service without seat rings, bushings, lantern rings, O-rings and other parts that are essential to proper equipment operation.

Look at the seal and the equipment as a part of a big picture.

Consider how this piece of equipment is affected by other equipment and control devices in the system. For example, is there a downstream valve that creates pressure spikes in an upstream pump seal when the valve closes and the pump is still operating?

Continue reading How to Investigate Compression Packing Failure Modes

BLUE-GARD 3300 for Refrigeration

In the late nineteenth century, Olin J. Garlock devised a better way to seal piston rods in steam engines. Since then sealing materials have been developed for various industrial applications. Over the years, different manufacturing processes such as calendering and beater addition have improved the performance of fiber sheet gaskets for these applications; however, design concepts for their formulation remain similar regardless of manufacturing method.

Figure 1: Microstructure of a compressed fiber sheet material ingredients: silicates [gray]—laminated structure; mineral [blue and aqua]—irregular/spherical shape; fiber [orange]—fibrillated, cylindrical or curly; silica, carbon black, or fine filler [red]—spherical shape; elastomer binder [yellow].

OVERVIEW OF MATERIALS

Many of the applications for compressed fiber sheet gaskets involve elevated temperatures and/or high pressure, which require high bolt loading in flanged joint assemblies. Various materials are added to the fiber-binder matrix to sustain this high compressive loading. To provide strength, different types of fibers such as p-aramid (Kevlar™), cellulose, polyester, glass fiber, carbon fiber, and others are added. Some of these fibers are organic materials, which limits their use at elevated temperatures. Minerals in cylindrical form provide balance in the formulation due to their high-temperature stability and strength. To form a compact structure, materials of different sizes are used, including silica, carbon black, and other micro-sized fillers. Figure 1 illustrates the ingredients and microstructure of a compressed fiber sheet material.

Continue reading BLUE-GARD 3300 for Refrigeration

KLOZURE® Oil Seals for All Industries

Klozure® Oil SealsKLOZURE® Oil seals from Garlock® KLOZURE® are available in a wide variety of configurations to meet the requirements of major industries. MILL-RIGHT® materials are used on all elastomeric seals for superior bearing protection. KLOZURE® Oil Seals are available in more than 50 different styles in sizes from ¼” to over 90″, solid or split, metal-cased or all-rubber.  KLOZURE® Oil Seals have had a strong brand presence in the U.S. since the 1920’s. Today they are also manufactured and branded in China and Germany.  Technology has advanced over the years, and the oil seals are now available in MILL-RIGHT® elastomers which provide longer service life than their predecessors.

There are many different styles and variations available from Garlock® KLOZURE®, but below are some of the more popular oil seals.

Continue reading KLOZURE® Oil Seals for All Industries

FDA Compliant PUR-GARD™ Bearing Isolator

PUR-GARD™ Bearing IsolatorsPUR-GARD™ bearing isolators offer the ultimate rotating equipment sealing solutions for the food processing industry. Manufactured with materials that are FDA compliant, metal detectable and x-ray inspectable while utilizing a patented IP66 design, Garlock PUR-GARD™ is a revolutionary seal that combines improved safety and overall process purity with cost savings through extended equipment and bearing life.

Features & Benefits

  • Patented labyrinth design provides bearing protection even in the most challenging environments, extending the life of rotating equipment
  • Unitized construction will not come apart during installation
  • IP66 in most common design configurations
  • Non-contacting design reduces shaft drag and energy consumption
  • Available in a broad range of configurations
  • Substantially reduced installation time – NO ARBOR PRESS NEEDED
  • No metal-to-metal contact
  • Metal detectable and x-ray inspectable

Typical Applications

Rotating equipment (pumps, motors, gearboxes) exposed to heavy wash down and/or zone 1 and 2 applications.

Continue reading FDA Compliant PUR-GARD™ Bearing Isolator

[VIDEO] Application Guidance for GYLON EPIX™

GYLON EPIX™ WebinarWe recently added the GYLON EPIX™ – The Next Generation in PTFE Gasketing webinar to our website.  The webinar discusses Garlock’s revolutionary new gasketing material, with its patented hexagonal surface, which concentrates gasket stress, providing improved compressibility and bolt load retention, improving sealability and blowout resistance.

Below is the third and final section of the webinar, which provides application guidance for GYLON EPIX™, calling out where it makes most sense to utilize this revolutionary new material.

[VIDEO] Features & Benefits of GYLON EPIX™

GYLON EPIX™We recently added the GYLON EPIX™ – The Next Generation in PTFE Gasketing webinar to our website.  The webinar discusses Garlock’s revolutionary new gasketing material, with its patented hexagonal surface, which concentrates gasket stress, providing improved compressibility and bolt load retention, improving sealability and blowout resistance.

Below is the second section of the webinar, which discusses the features and benefits of the GYLON EPIX™ material, and what differentiates it from any other gasketing material on the market today.

[VIDEO] Introduction to GYLON EPIX™

GYLON EPIX™ WebinarWe recently added the GYLON EPIX™ – The Next Generation in PTFE Gasketing webinar to our website.  The webinar discusses Garlock’s revolutionary new gasketing material. With its patented hexagonal surface, GYLON EPIX™ concentrates gasket stress, providing improved compressibility and bolt load retention, improving sealability and blowout resistance.

Below is the first section of the webinar, diving into what drove Garlock to create this new material, and how GYLON EPIX™ provides the benefits of both a 1/16″ and 1/18″ thick gasket in one, universal, 3/32″ thickness.