How Industrial Gas Sampling Engineering Can Provide Budgetary Relief

Grab sampling is an important aspect of many fluid industries. Samples, when drawn leveraging best practices and within a safe environment, help industries meet their sampling goals with ease. A small mistake while designing or managing grab sampling components can lead to process anomalies—which often go undetected and call for costly reworks with the passage of time. 

Understanding the nature of your sampling fluid and implementing custom designs are the keys to optimizing operational costs and improving yielding while keeping reworks to the minimum. 

In this article, we discuss common grab sampling challenges and the role industrial gas sampling engineering plays in optimizing process costs.

Grab Sampling Challenges

Here are some of the most commonly seen grab sampling challenges. 

Sample Handling 

Failure to handle samples wisely can compromise their representativeness and the safety of the technician. For instance, trying to capture high-pressure liquid without a proper container can cause a spillover of the process fluid. Apart from liquid wastage, it may also violate essential HSE codes if the liquid is toxic in nature. Sometimes, samples are carried in an open bottle to the lab. If the sample has light components, they may start evaporating or fractionating in the absence of proper temperature and pressure. 

The same is true for gas samples, except for the fact that their accidental release into the atmosphere may cost a refinery for exceeding the fugitive emission quota.  

Needless to say, in the absence of proper grab sample guidance, such unfortunate situations would cost you in materials in the long run.

To eliminate these problems, facilities use fixed-volume liquid sampling. The system will capture a fixed volume press of liquid inside a pressure-rated container leaving 20% space free, enabling thermal expansion of the fluid. However, it is also important to select the right type of container for your samples. 

Choice of Containers 

Captured samples are prone to contamination under various circumstances. In the absence of fixed-volume, air-tight containers, the process fluid is prone to accidental breakage and contamination. Thus, it is imperative to select an ideal container. 

There are two types of options available:

1. Bottle containers
2. Cylinder container 

Here is a quick comparison between the two types. 

Swagelok’s Grab Sampling Module (GSM), Grab Sample Cylinders (GSC), and Liquid-Only Sampling System (GSL) are designed to offer leak-proof containment with advanced industrial gas sampling engineering at the core. 

To offer ease of use, Swagelok grab sample cylinders can be configured with optional handles and quick connect fittings. You can also add a bypass tube for purging. 

Inaccurate System Response 

It is important to accurately measure the time required for the sample to reach from the tap line to the analyzer, also known as the lag time. The lag time of a grab system is calculated by taking the volume and flow rate of all the associated components into account. The mode of calculation also changes depending on the sample type: liquid or gas. 

Even a small calculation error repeated over a number of samples can cost you a huge loss in terms of waste of process fluid and time. 

Ideally, a superior process control offers a time delay of not more than one minute. If it exceeds more than one minute for your existing sampling modules, you should look for optimizing delays in every possible system component, including the probe, sample transport, sample conditioning, and analyzer. Partnering with a team of local expert Field Engineers can help you analyze the cause faster.  

Other Grab Sampling Deficiencies 

Some problems may not directly influence cost but can certainly negatively impact sampling efficiency and operator safety. Two such common problems are improper labeling and unoptimized sampling locations. 

Improper Labeling 

Proper labeling is one of the fundamental aspects of industrial gas sampling engineering best practices. In the absence of precise labeling of grab sampling points and their associated components, new technicians, for example, may be susceptible to making mistakes while collecting samples. The collection of samples inside a container not dedicated to their chemical composition may compromise workplace safety and sample quality. Thus, it is important to create an asset register for each sample point, including tags for container type, fluid nature, different parts, flush time, frequency of sampling, etc. 

Unoptimized Sampling Locations 

The location of sample points greatly influences the operational efficiency of sampling. For instance, sample stations installed over a control valve get no flow when the valve is closed. Also, there is no predictable pressure drop when the valve is fully open. The best locations to ensure maximum drawing efficiency could be over a pump or on either end of a process line. Even choosing end-product lines would no longer require you to be concerned about valve position before sampling. 

A fair knowledge about all such sampling mistakes and the working knowledge to avoid them is necessary to meet your sampling goals, safely and efficiently. 

Get Local Support for Industrial Gas Sampling Engineering 

Swagelok’s team of experts can evaluate your sample systems and assess your process against industry best practices. They track your system to offer time-sensitive information to address any potential issue before it’s too late. As a result, the operational cost and labor-intensive maintenance are reduced, and the system performs at its peak, ensuring maximum return on your investment.

To find out more about how Swagelok Northern California can help you incorporate industrial grab sampling engineering best practices for ensuring representative samples, contact our team today by calling 510-933-6200.

About Morgan Zealear | Product Engineer, Assembly Services

Morgan holds a Bachelor of Science in Mechanical Engineering from the University of California at Santa Barbara. He is certified in Section IX, Grab Sample Panel Configuration, and Mechanical Efficiency Program Specification (API 682), and he is well versed in B31.3 Process Piping Code. Before joining Swagelok Northern, he was a manufacturing engineer at Sierra Instruments, primarily focused on capillary thermal meters for the semiconductor industry (ASML).