Mike Sondalini — Thought Leader

Dust control concepts. Industrial dust is the result of material escaping from the confines of a process or a storage location. The size of the problem depends on the dust’s characteristics and the means of its distribution. The best policy to control dust is to not let it escape from where it ought to belong. There are simple techniques that can be used to manage dust and prevent it from becoming a major health and environmental problem once the mechanism of creation and distribution are under stood. [Read more…]

Non-destructive testing of welds. Welding processes and methods can introduce contaminants and metallurgical defects into the weld. If a weld is required to withstand severe loading conditions and stresses it is critical to insure its quality meets minimum standards. Welds can be tested by destructive and non-destructive techniques. Most production is tested by use of non-destructive methods. The most common non-destructive tests to check welds are Visual Inspection, Liquid Penetrant, Magnetic Particle, Eddy Current, Ultrasonic, Acoustic Emission and Radiography. Keywords: NDT, quality control, non-conformance, verification, weld procedure. [Read more…]

Electric motor variable speed drives operation. Alternating current electric motor speeds can be changed by the use of a frequency converter. This device changes the frequency of the alternating current to the motor. This then changes the rotating speed of the motor’s internal magnetic field. The speed of the rotor responds accordingly and so allows for variable speed control of connected items. When these devices are used there are several issues that need to be addressed to insure successful selection and long-term operation. Keywords: VSD, precise speed control, over- speed, motor controller, frequency inverter. [Read more…]

Work within the design limits – Once equipment or a process is allowed to run outside it’s design limits it will fail quickly. The only way to get long-lived, well operating plant and equipment is to keep its individual components working within their service limits throughout their life. Keywords: training manual, procedures, operator manual. [Read more…]

Plant compressed air waste control. Every compressed air system will eventually develop leaks from connectors and redundant pipelines. Compressed air is very expensive to make. It is necessary to institute regular inspections for air leaks and fix them immediately.

Keywords: pressure loss, energy loss, air compressor, pressure switch. [Read more…]

Metering and dosing pump operation. Any positive displacement pump can be used as a metering or dosing pump. The purpose of these pumps is to inject a known volume of liquid into a process stream. The primary requirement is that over a given period of time the pump consistently delivers the same amount of liquid. Keyword: gear pump, piston pump, helical rotor pump, diaphragm pump, peristaltic (hose) pump, additive, dosing rate. [Read more…]

Is your scrubbing tower working? A wet scrubbing tower is used to clean odors, particles, mists and vapours from a gas stream. The gas is forced through the tower. As it moves from inlet to outlet it is washed and cleaned. The washing is done with suitable chemicals that remove the active components in the gas flow. The gas is cleaned to environmentally acceptable levels and discharged to atmosphere. Keywords: packed tower, packing, fill, mist eliminator. [Read more…]

Abstract

Flow meters – don’t believe what they tell you. A flow meter is an instrument that measures the amount of fluid (liquid or gas) that passes through it. The meter in the pipe is the detecting device and increases the count when a specific quantity of fluid passes by. There are several types of flow meters in common use. They include magnetic flow meters, vortex flow meters, mass flow meters, turbine flow meters, rotor blade meters, paddle flow meters, and ultrasonic flow meters. Usual the quoted accuracy on the flow meter specification sheet is for water at 20oC. However when the meter is installed in a process application it is unlikely that the meter will meet the quoted accuracy without site-specific calibration. Keywords: calibration, certified test equipment, flow meter accuracy.

The manufacturer performs laboratory trials of its equipment to insure the flow meter meets their claims for accuracy. Since the manufacturer does not know where their meter will be used they standardise the tests by using water at known conditions. Unless the meter is used in a situation identical to the laboratory conditions the given accuracy is unlikely to be achieved. [Read more…]

What you will learn from this article.

• Glued plastic pipes must have the joints prepared before gluing.
• Some plastic is joined with glue while others are solvent joined.
• Glued joints do not bond with the plastic but must be ‘hooked’ to it.
• Install thrust brackets if large glued pipes change direction sharply.

Some plastics can be joined with glues or cements. One of the most common of these is PVC. PVC can be either unplasticised (uPVC) or chlorinated (cPVC). Some plastics can be dissolved and chemically bonded together. ABS plastic is such a plastic. [Read more…]

What you will learn from this article.

• There are two ways to detect holidays in tank linings.
• Explanation of the low voltage ‘wet sponge’ method of testing linings.
• The second method is high voltage spark detection.
• Importance of confirming the presence of sufficient liner thickness.
• The likely trouble spots where linings can thin.

[Read more…]

What you will learn from this article.

• The types of forces developed in a turning agitator.
• Gearbox position and configuration for long-life.
• Bearing arrangements to minimise gearbox loading.
• Simple, strong agitator support arrangements.
• Vapour seals are needed to stop fumes escaping.
• Lots of low maintenance selection and design tips.

Agitated vessels and tanks are common throughout the process and chemical industries. A properly sized agitator with correct proportions to suit the tank will deliver well-mixed product. A correctly sized gearbox with well-chosen bearings and bearing arrangements will need only regular lubrication while giving years of trouble free service. [Read more…]

What you will learn from this article.

• Control loops automatically correct unwanted changes in a process.
• A control loop consists of components to detect and adjust the process.
• Control loop complexity reflects the accuracy and speed of control.
• Explanation of ‘open loop’, ‘closed loop’, ‘feed back’, ‘feed forward’.

The sole purpose of using process control in, say, the making of beer, is to detect what is happening during manufacture and to decide if something needs to be changed to insure the beer meets the necessary specification. The key words are ‘to detect’, ‘to decide’, ‘to change’ and ‘to meet specification’. A control loop can do all these things automatically. [Read more…]

What you will learn from this article.

• An explanation of root causes analysis (RCA)
• An overview of how it is applied at your work place.
• See the result of a sample RCA.

Root Cause Analysis is a step by step method that leads to the discovery of a fault’s first or root cause. Every equipment failure happens for a number of reasons. There is a definite progression of actions and consequences that lead to a failure. An RCA investigation traces the cause and effect trail from the end failure back to the root cause. Much like a detective solving a crime. [Read more…]

What you will learn from this article. 

• How cyclones and hydrocyclones work.
• Where cyclones are used.
• Design features that affect cyclones.
• How to get long life from cyclones.

A tornado can lift cars from the ground and hurl them hundreds of meters away. Chickens and ducks can be hurled kilometers away. The story of fish falling from the sky is explained by the power of a tornado to lift materials kilometers into the sky. The spinning vortex of air separates and segregates heavy and light objects. The heavy objects drop out sooner and the light objects are carried further. Cyclone separators and hydrocyclones work the same way. [Read more…]

What you will learn from this article. 

• How forces are distributed through an object.
• Force diagrams are used to represent forces on an object.
• Position and direction of a force determines the type of stress.
• How to redistribute force in a structure.

Why don’t you fall to the ground when you sit in a chair? Why doesn’t the roof fall in on top of you? We don’t expect these sorts of things to happen. But at times chairs fail and people fall to the ground and at times roofs fall on people. When structures are put under sufficient stress they will fail. [Read more…]