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Incremental Core Extruding Apparatus

  • Paleoecological analysis
  • Precise, incremental core sample extruding and sectioning

Standard Incremental Core Extruding Apparatus

  • Incremental extrusion/sectioning of standard (68mmid) core samples x 5 or 10 mm thick
  • Barrel capacity: 68mmid (2 5/8”) x 71mmod (2 ¾”) x 120 cm long
  • Adjustable bushing set, extruding rod, footpad, threaded "stop" plate, base plate
  • 6 each x 1 cm thick spacer plates
  • Core extruding funnel assembly

Large-Bore Incremental Core Extruding Apparatus

  • Incremental extrusion/sectioning of LARGE BORE core samples 5 or 10 mm
  • Barrel capacity: 95 mm x 100 mm x 60 cm long
  • Adjustable bushing set, extruding rod, footpad, threaded "stop" plate, base plate
  • 6 each x 1 cm thick spacer plates
  • Core extruding funnel assembly

Incremental Core Extruding Apparatus

  • The Incremental Core Extruding Apparatus enables one to carefully extrude mud from the “bottom-up” in a standard Clear Polycarbonate Core Barrel: 2 5/8” ID X 2 ¾” OD X 1.2 m long (or shorter). The assembly comes pre-assembled for ease of use. A stable work platform is required for any coring operation. This method requires some time and effort to master, but produces good results. Below, please find some directions and photos on how the use the Extruder assembly.
  1. Footpad… Use wood screws x 2 ½” long to secure the footpad to plywood or floor. Screw on the Threaded Extruding Rod until it reaches the floor and tighten the ¾” nut/washer against the footpad.
  2. Barrel Funnel… Used to focus sediment sample into narrow path so it can be transferred into small sample container. Push the funnel down over the top of Core Barrel until it stops. Use a Hex Driver to tighten collar to Core Barrel.
  3. Extruding Plug…This part is inserted into the core barrel at time of collection. See “O” rings below.
  4. Extruding Disk… This is screwed to the top of the Extruding Rod and butts against the above Extruding plug during extruding process.. It may not be necessary to use “O” rings on this disk depending on the nature of the sediments.
  5. Core Barrel Stabilizer Disk…this part is used to stabilize the bottom of the core barrel during the extruding process. This disk freely glides up and down on the extruding rod. Lubricate the “O” ring and insert Disk into Barrel using a twisting/turning action to seat properly.
  6. Spacer Plates (10 mm thick)… These plates are used as gauges for extruding precise 10mm horizons from the Core Barrel. These Spacers are used in conjunction with the below Adjuster Disk.
  7. Adjuster Disk… This disk acts as a “stop” and allows one to extrude thicker layers without ‘over’ extruding. The disk is threaded so it can be spun up or down on the Extruding Rod.
  8. “O” Rings…Clear Polycarbonate Core Barrels have nominal variation of their inside diameter between production runs. This can sometime affect the fit of “O” rings. First, lubricate all “O” rings with clean water or dry silicone spray before use. It may not be necessary to use “O” rings at all depending on the nature of the sediments. You may be required to “tune in” an “O” ring fit by using commonly found Teflon tape. Increase tension of “O” ring by wrapping Extruding Plug groove with several wraps of tape. Reinsert “O” ring and test fit. If “O” rings become dislodged during extruding or squeezing; wrap the Teflon tape on outside of disk to keep the ring captive. Reinsert and test fit.

General Procedure:

  1. Mount Core Barrel (with Core Extruding Plug in place) atop of the Extruding Disk.
  2. Pull Core Barrel downward approximately 10 cm and insert the Core Barrel Stabilizer Disk. Lubricate the “O” ring and use a twisting/pushing action to seat this disk and “O” ring properly.
  3. Siphon off any overlying water off the top of the core sample
  4. Pull Downward on the core barrel until the top of the sediment is even with top of barrel/funnel.
  5. Insert the Spacer Plates below the Core Barrel Stabilizer Disk and above the Adjuster Disk.
  6. Spin the Adjuster Disk upwards until it touches the set of Spaces.
  7. Remove Spacer Pate and pull Core Barrel downward to expel exactly 10 mm of sediments from the barrel.
  8. Scrap sample from funnel to sample container.




Core Extruding Apparatus Includes:

  • corecore tube funnels
    • standard sizes fit 7.5 and 10.0 cm outside diameter polycarbonate core tubes
    • polyethylene runway with clear polycarbonate walls; stainless steel thumb screws secures funnel to core tube
    • polycarbonate spatula

  • polyethylene piston assemblies
    • adouble integral "O" ings
    • hex nut can adjust the tension of the piston assembly at any point in the tube by using the adjustment wrench on the end of the extrusion rod

  • incremental extrusion rod
    • used to precisely expel short sections (1.0 cm) of sediments
    • a polyethylene baseplate supports the core tube bottom and freely slides along the extrusion rod; the core tube is pushed down until the sediment reaches the top of the tube

  • rigid polycarbonate spacers
    • (1.0 cm height) are stacked to the 2.5 cm diameter aluminum extrusion rod between the baseplate and footpad
    • sediments can be precisely expelled as bushings are removed and core tube is pushed down in 1.0 cm intervals






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