Grab Sampling Systems

Sample Cylinder Accessories

Several options are available for your grab sampling system, such as additional instrumentation - gauges, flowmeters, and transducers; sample coolers—sentry sample coolers; process connections—threaded and flanged connections; enclosures and stands; automation—add a pneumatically or electrically actuated valve to automate your sampling sequence; and exotic alloys—certain components are available in alloy 400, alloy C-276, or alloy 600. 

Outage Tubes

• Made from 316 stainless steel or alloy 400 tubing
• Offered in 1/4 or 1/2 in NPT sizes
• Marked "Outage Tube" for identification

Outage tubes provide a vapor space of the desired volume in cylinders containing liquefied gases, so that liquid in the cylinder can expand if the temperature increases. Without enough vapor space, a small temperature increase can cause the liquid to expand and increase the pressure dramatically. Outage tubes are welded to the male inlet end of an adapter or tee. This adapter or tee is then threaded into the female port of a sample cylinder. The tubes can also be welded directly to the male inlet of a Swagelok non-rotating stem needle valve. The valve is then threaded into the female port of a sample cylinder.

Nonrotating-Stem Needle Valves

• Compact, rugged design is available in straight and angle flow patterns
• Protective handle prevents contaminants from entering functional valve parts
• Orifice sizes from 0.093 to 0.218 in. (2.4 to 5.6 mm) are available.
• Flow coefficients (Cv) from 0.12 to 0.53 are available
• Female NPT, male NPT, Swagelok tube fitting, and mixed end connections are available
• Pressures up to 3000 psig (206 bar)
• Temperatures up to 450°F (232°C) with PEEK stem tip
• Stainless steel, brass and alloy 400 materials

Needle valves have a preferential shutoff direction for restraining pressure and the valve will be oriented such that it is best situated for resisting the internal pressure of the cylinder. The D Series is widely used due to its replaceable stem tip and compact handle.

Rupture Disc Units

Swagelok rupture disc units protect sample cylinders from over pressurization by venting the cylinder contents to atmosphere. The use of a rupture disc is recommended with chemicals that may rapidly expand and pressurize due to temperature changes.

The rupture disc is welded to a body that is threaded into a valve body or a rupture disc tee and sealed by an elastomer O-ring. The rupture disc can be easily replaced without removing the valve or the tee from the cylinder.

Carrying Handles

The carrying handle is an optional purchase that provides a convenient and safe way to carry sample cylinders. The handle is constructed of 304 stainless steel and is available for use on 300 cm3 and larger cylinders.