Syringe Plunger Types
Microliter Plungers
Below is the standard, stainless steel plunger found in 2.5 – 500 µL volume Hamilton Microliter syringes. This plunger is hand fitted to the glass barrel to a tolerance of millionths of an inch to create a liquid tight seal ideal for dispensing solvents. When using samples without dissolved particles, the Microliter plunger has an almost unlimited lifespan because there are no wear surfaces. Also, these plungers are not interchangeable between syringes or replaceable due to the custom manufacturing process.
7000 Series Microliter Plunger
This plunger is exclusively for 0.5 – 5 µL volume 7000 series syringes. The end of the plunger has a tungsten wire extension that fits the entire length of the needle all the way to the tip, resulting in zero dead volume. This 7000 series syringe is used for dispensing minute liquid volumes.
Gastight Plungers
Hamilton manufactures a variety of Gastight plungers depending on the intended use of the syringe. All Gastight plungers are made of stainless steel or aluminum and feature a polymer plunger tip, often PTFE. These plungers can be used for manual or automated applications with liquids or gases. The plungers are interchangeable and replaceable for 10 µL – 100 mL volume syringes.
Manual Plungers
Syringes equipped with either the standard dome-shaped plunger or the X-Style Plunger (detailed below) can be used manually. Syringes smaller than 1 mL feature the standard dome-shaped plunger button. Syringes 1 mL or larger feature PTFE-coated X-Style Plungers which are designed for both manual and automated use.
X-Style Plungers
X-Style plungers feature a 6-32 threaded hole which is commonly used to mount the plunger into a syringe drive. For syringes 500 µL and smaller, the plunger button also functions as a stop which contacts the glass at the end of the stoke to protect the delicate plunger wire and plunger tip. Syringes 1 mL and larger feature a PTFE-coated plunger designed for both manual and automated use.
XP-Style Plungers
This plunger is used on XP-3000 modular digital syringe pumps and has a stop to limit damage to the plunger tip. This plunger is for half-height syringes with a 30 mm stroke length.
XL-Style Plungers
This plunger is used on the XL-3000 modular digital syringe pumps and has a stop to limit damage to the plunger tip. This plunger is for full-height syringes with a 60 mm stroke length.
XB-Style Plungers
This plunger features a stop and a back bushing. The back bushing increases the plunger tip life, maintains proper plunger alignment and reduces the particles generated by plunger and glass contact.
Bubble Free Prime Plungers (BFP)
Bubble Free Prime Syringes are designed to work seamlessly with Hamilton's Bubble Free Prime Valves, which are commonly used with the PSD/4, PSD/6, and Microlab 600 systems. The conical plunger tip extends through the termination of the syringe and into the valve. This design effectively eliminates trapped air from within the syringe termination, reducing the number of cycles required to prime the system.
Reinforced Plungers (800 and 1800 Series)
Small volume syringes require extremely small plunger wires. For uses that are prone to bending and breaking these small plungers, it is recommended using a reinforced plunger. These plungers are available in both Microliter and Gastight versions in the 800 and 1800 syringe series respectively.
