LT and BT Tube Sizes

The LT tube extended valves are equipped with a 1/4" (6.4mm) OD tube to reach active oil zones in gearboxes and reservoirs. The 1/4" tube is ideal for low viscosity fluids operating at warm temperatures. BT tube extended valves come standard with a 3/16" (4.8mm) OD tube and are suitable for higher pressure applications.

Sampling high viscosity gear oils in cold climates can be slower if using a regular 1/4" tube. Checkfluid originated a 5/16" (8mm) OD tube option on the LT tube extended valves designed for cold climate sampling or sampling viscous gear oils. The increased tube diameter allows for better flow and can be used in conjunction with a SLF5 or a LF-5Q probe which also uses 5/16" OD polytube for even greater flow. Sampling with a 5/16" LT tube valve along with a 5/16" polytube on a SLF5 or LF-5Q probe can reduce purge and sample times by up to 20%.

It is important to run the system before sampling to ensure the fluid is at normal operating temperature to draw a representative sample and to allow for easier sampling due to lower fluid viscosity. Standard vacuum pumps can also be used to sample with the 5/16" polytubing to allow for low pressure vacuum sampling.