Dry-Running Sealing Technology: Pump Applications (P1)

Non-contacting, dry-running seal technology, a revolutionary technology for pumping equipment, was developed and pioneered by John Crane and meets the USA Clean Air Act of 1990. This Act defines emission standards for rotating equipment. Designed for emissions control, this sealing concept has resulted in improved reliability, efficiency, and cost benefits when compared to competing technologies such as canned and magnetic drive pumps.

A non-contacting, dry-running seal solves the tribological problems when pumping certain fluids rather than transferring those problems to other areas of the equipment as in the case of competing technologies.

Many plant operators have a Mean Time Between Planned Maintenance (MTBPM) of less than two years. In some cases, equipment is down for repair every two to three months. This has a major impact on the cost of owning the equipment and may also impact the amount of product being manufactured. By properly applying non-contacting, dry-running seal technology, the benefits in improved reliability are significant.

What the User Expects

The user expects exceptional performance throughout the life of the equipment. Running a plant with fewer operators and mechanics means the complete pumping system must run when it is needed and last a long time. The pump must operate safely and meet existing regulations while reducing cost. Pump and seal systems are vital to a plant’s operation. They must be carefully selected for each application to achieve the design reliability.

Causes for Short Seal Life

At the 1997 International Pump User’s Symposium in Houston, TX, users attending a forum on mechanical seals were asked to identify the causes for short seal life at their plant. The problems identified were:

· Improper operation of the pump

· Dirt flushed in the seal chamber

· Start-up without venting

· Vibration of equipment

· Misalignment/pipe strain

· Worn seal chamber bushing

· Pump control/level flow control

· Installation

· Loss of seal flush

· Cavitation

· Process problems

· Low NPSH

· Dry run

Solutions to Common Problems

Dry-Running Sealing Technology: Pump Applications (P2)

Comments

5 Important Maintenance Metrics and How To Use Them

By Bryan Christiansen, Limble CMMS. Source : maintworld.com Effective maintenance of equipment is a critical factor in delivering quality operations that provide timely resources at a minimal cost. However, those in the maintenance field understand that equipment reliability does not come easy. Organizations need to set quality benchmarks to measure the current effectiveness and predict future performance and use the data obtained to understand where to make improvements. One way to do this is by using different maintenance metrics to understand the equipment performance. These metrics are very important as they can mean the difference between achieving the overall business goals and explaining how unexpected breakdowns caused yet another production delay. Maintenance Metrics You Should Be Measuring What are the maintenance metrics? There are two categories of maintenance key performance indicators which include the leading and lagging indicators....

[Read more...]

Why Pump Shafts Often Break at the Keyway Area

By NTS Pump shaft failure can lead to significant downtime and repair costs in industrial plants. One of the most common locations for pump shaft failure is at the keyway area. In this article, we will explore the reasons why pump shafts often break at the keyway and what can be done to prevent such failures. The keyway is a high-stress point (weakest point) on the shaft, where a key is inserted to transmit torque between the shaft and the pump impeller or coupling. During operation, the keyway experiences cyclic loading that creates a bending moment in the shaft, which is concentrated in the keyway area. Over time, this cyclic loading can cause fatigue failure in the shaft material, leading to a fracture at the keyway. In addition to cyclic loading, other factors can contribute to shaft failure at the keyway. Improper keyway design or installation can lead to stress concentrations or inadequate clearance between the key and keyway . Misalignment or overloading can also cause ex...

[Read more...]

Preventing Motor Bearing Damage from Shaft Current with the AEGIS® Ring

Electric motors are the workhorses of modern industry, powering everything from pumps and fans to conveyor belts and heavy machinery. But these vital components are not immune to wear and tear, and one common problem that can lead to premature motor failure is bearing damage caused by shaft current. Shaft current is a type of electrical discharge that occurs when there is a voltage potential between the motor shaft and the bearing, resulting in the flow of electrical current through the bearing. This current can cause a range of problems, including pitting and fluting of the bearing surfaces, which can lead to premature wear and failure. Shaft current Motor shaft current can have several harmful effects on bearings, including: 1. Bearing pitting and fluting: Electrical discharges can cause tiny pits and flutes to form on the bearing surfaces, leading to premature wear and failure. 2. Bearing noise and vibration: Shaft current can cause ...

[Read more...]

WHAT IS THE ULTRASONIC IN-LINE INSPECTION (ILI) PIGGING?

In-line inspection (ILI) of pipelines has established itself as the most efficient tool for evaluating the condition of a pipeline and an indispensable part of pipeline integrity management. Historically, there have been two major technologies used in in-line inspection for corrosion, the magnetic flux leakage (MFL) and ultrasonics (UT), each having their distinct properties and fields of application. Ultrasonic (UT) ILI has always provided unique quality of information about the pipelines, rendering highest accuracy and tightest measurement tolerances. In the 1990s ultrasonic tools for detection of cracks have become available. Ultrasonic measurement principle: ultrasonic transducer slides along the internal surface of the pipe wall measuring distance to the wall and the wall thickness (top), yielding the stand-off and the wall thickness (bottom two B-scans) Ultrasonic (UT) based In Line Inspection tools for all types of liquid filled pipelines. This includes Ultras...

[Read more...]

Dry Gas Seal Failure Modes

BY BHUSHAN NIKAM. Invented in the mid-20th century and typically equipped in process gas centrifugal, dry gas screw compressors and expanders, dry gas seals (DGS) are the preferred gas lubricated dry seal solutions available on the market. They have become the standard for new machines. DGS are robust, simple, consume less power, and are more efficient in reducing leakage than their predecessor. Various configurations such as tandem with and without an intermediate labyrinth ( Figure 1 ), single ( Figure 2 ), and double ( Figure 3 ) are available & shall be selected based on process requirements. In this article, we discuss the various DGS failure modes and how they should be addressed: PRESSURIZED HOLD/STANDBY Pressurized hold, also called settle-out condition, occurs when the compressor remains at a standstill, but the casing is pressurized. If an alternate process gas lacks sufficient pressure and flow, process gas enters the seal cavity through the process labyrinth ...

[Read more...]

Industrial Maintenance Solutions

Search This Blog