New Technical Briefing: Grab Sampling Best Practices with Mike Strobel

Learn about a recent presentation on grab sampling best practices by Swagelok's Mike Strobel, BSc., IE, Field Engineer/Americas.

Recently Edmonton Valve customers attended a briefing by Swagelok's Mike Strobel that focused on best practices around grab sampling.

Grab sampling is the science of safely capturing a sample from a process, pipeline, or tank while maintaining the chemical composition during storage or transport for later analysis. Worker safety and ensuring samples are representative and timely are grab sampling's main goals. Other common names for grab sampling are "laboratory sampling", "field sampling", and "spot sampling".

Grab sampling is particularly important for:

• Validation of process conditions
• Validation of the spec of end products
• Validation of online analyzers
• Loading platforms, reference sample of sold product
• Registration of environmental emissions according to local regulations

There are three key design considerations, having to do with continuous flow, "flush" time, and purge fluid. With respect to cylinder sampling, specifically, Strobel says best practices call for operators to:

1. Fill in vertical orientation
2. Fill liquid from the bottom of the cylinder (this ensures a full cylinder; ensure you use an outage tube, which creates vapor space to avoid over pressurization)
3. Fill gas from the top of the cylinder (so any liquid droplets shoot straight through and any liquid on the walls is pushed out the bottom or drained by gravity)

With respect to bottle sampling, best practices call for operators to:

1. Use needles and septum (make sure to consider viscosity of the fluid and particle size when sizing needles)
2. Use shroud to guide bottle into needles (this reduces the risk of bending needles)
3. Use a fixed volume sampler if overfilling is a concern
4. Never flow or dump onto the ground

Replay this recorded technical briefing here:

Configurable. Local. Reliable.

Swagelok grab sampling systems satisfy gas and liquid non-slurry sampling service in a consistent, reliable package. Two system types allow for capture into one of two types of containers: pressure‑containing metal cylinders as found in the Grab Sample Module (GSM) or non-pressure‑containing glass or polyethylene bottles as found in the Liquid Only Sampling Module (GSL). 

Visit the section of our website devoted to showing you the innovative grab sampling solutions Swagelok has brought to market:

Also see:

• Grab Sample Modules Offer Speed and Flexibility
• Video: How Swagelok's Grab Sampling Systems Compare
• Are Your Grab Samples Always Representative and Timely?