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Gluing Plastic Pipes so You Can Trust Them

Gluing Plastic Pipes so You Can Trust Them

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…]

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Walking on Shifting Sands in the Age of Uncertainty

Walking on Shifting Sands in the Age of Uncertainty

Guest Post by Geary Sikich (first posted on CERM ® RISK INSIGHTS – reposted here with permission)

“To do something very dangerous takes a certain lack of imagination”
 – Anonymous

Introduction

Governments and companies worldwide are emerging from the current financial crisis and subsequent recession.  While governments are crafting new regulations, businesses around the world are walking in shifting sand as risk exposures are high and new regulations will create compliance challenges.  According to a recent survey by Korn/Ferry International, corporate leaders are focusing more attention on risk management after what is considered by many to be excessive risk-taking during the boom times that factored into the global financial crisis. [Read more…]

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The Fault with Design Freezes

The Fault with Design Freezes

The effectiveness of “Design for X” (DfX) methodology is often limited by the non-negotiable “freeze” gates in the product development process.  Freezes become points of negotiation instead of directing scheduling and resource decisions.  Design changes continue past “design freeze” commonly resulting in an inefficient multi-iterative process.

A design freeze is the wrong tool for the job.  Design Freeze is a “Put your pencils down” methodology.  This leaves no room for input to the decision to halt activity other than what was available when the freeze gate was set.  Often a good deal of new information about the design and program has been created between the program creation and the freeze. [Read more…]

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Test To Bogy Sample Sizes

Test To Bogy Sample Sizes

Test To Bogy Sample Sizes

Introduction

Reliability verification is a fundamental stage in the product development process. It is common for engineers to run a test to bogy (TTB).  What sample size is required for a TTB?

Reliability Testing

Reliability is the probability of a part successfully functions under specified life, duty cycle and environmental conditions. Many functions are specified during the design process. Each reliability test will be focused to validate a specific function. The targeted verification level depends on the criticality of the function and potential failure modes. The life could be specified as a count of cycles, an operating time, or perhaps a mileage or mileage equivalent. The duty cycle is a description of how the device is used. Environmental stresses are generally included in the test. 

[Read more…]

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Small Satellites, Emerging Technology and Big Opportunities (part one of seven) – Reliability and Awesome New Things

Small Satellites, Emerging Technology and Big Opportunities (part one of seven) – Reliability and Awesome New Things

Two rockets launched from Earth in November 2013. They carried a total of 61 small satellites from 20 different manufacturers. A satellite that is less than 500 kg in mass is considered ‘small.’ But small satellites are unique in many other ways. Old and ‘big’ satellites are massive, multi-billion dollar machines that take years to build and are the ‘only shot’ at achieving a mission. A ‘big satellite’ that stops working is a disaster. If a ‘small satellite’ fails, there can be many others floating around Earth to pick up the slack. [Read more…]

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What Can You Do With Data?

What Can You Do With Data?

A Question & Answer Period with Fred Schenkelberg and James Kovacevic on what can be done with your data and analysis.

Data and the analyses that use the data can be tricky to manage at best, let along extremely difficult.

In this last post of the series on using the maintenance data you have, Fred and James will answer many of the common questions asked about data and the analyses. [Read more…]

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Project Governance and Resource Management

Project Governance and Resource Management

All projects or programs have a formal or informal resource management process, with the goal of completing projects on time, within budget and with good project quality.

In order to meet this goal, the resource management objectives are:

  • the quantity of estimated resources is accurate
  • the resource role requirements are clear and precise
  • the resources meet or exceed the expectations (requirements)
  • the resources are added in a timely manner
  • cost of the resources is minimized to the extent possible

[Read more…]

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Holiday Detection in Above-ground Tank Bottom Lining Inspection

Holiday Detection in Above-ground Tank Bottom Lining Inspection

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…]

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Intellectual Abuse: A new Problem in the Workplace

Intellectual Abuse: A new Problem in the Workplace

Guest Post by Malcolm Peart (first posted on CERM ® RISK INSIGHTS – reposted here with permission)

In the workplace we have identified and attempted to eradicate racial and gender discrimination, sexual harassment and bullying.  We now battle age discrimination in our aging society in a (supposedly) increasingly politically correct world.  However, our intellects are also being abused as individuals find increasing ways to breach of the bounds of reasonable behavior and put our sanity and dignity at risk. [Read more…]

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Over Priced Brands

Over Priced Brands

I find it interesting when high end brands look to maximize profit by going for the money grab of lowering quality while maintaining price point.  It seems so foolishly short sighted. The amountof work that goes into creating a highly reputable brand is extensive and decades in the making.  Brands can be tarnished very quick and very difficult to recover.  So why do this?  A few reasons I have seen:

[Read more…]

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The 6 Signs of a Failing Plant

The 6 Signs of a Failing Plant

About a year ago, I wrote an article about the 6 signs of a reliable plant that got warm reception and a few nice comments. More interesting however was a private message I received from a Reliability Engineer who asked if I had a list of signs that a plant was in chaos and needed a wake up call to turn things around. I responded to the note, drafted a title page and a list of some of the sure signs a plant is in trouble.

This is the resulting article. [Read more…]

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The WHAT and, More Importantly, The WHY of the Weibull Analysis

The WHAT and, More Importantly, The WHY of the Weibull Analysis

How to conduct a Weibull analysis and the questions the analysis will generate.

Every failure is part of a puzzle. The equipment we are maintaining is trying to communicate with use with each and every failure.
Often the message is not obvious.

There is the immediate failure. And, if we’re paying attention we can sort out the root cause of the failure along with replacing or repairing the damaged parts. Sometimes though the damage is caused by another issue with the system.

Something was hidden. [Read more…]

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Set-up Tank Agitator Gearboxes for a Long Life at Low Cost

Set-up Tank Agitator Gearboxes for a Long Life at Low Cost

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…]