Limnological, Hydrobiological, and Oceanographic Sampling and Monitoring Equipment
We are the USA Representative for Duncan & Associates.
Duncan & Associates are designers, manufacturers and suppliers of limnological, hydrobiological and oceanographic sampling and monitoring apparatus. They also supply sampling equipment for waste and industrial bi-products, discharges as well as active wastes.
Their equipment is manufactured to an assured standard and has been proven and tested over many years.
Customer base is extensive worldwide, and covers a wide range of users including University Departments, Research Institutes, Offshore Oil and Power Industries, Marine and Oceanographic Institutions and their vessels, Environment Agencies and River Authorities, Nuclear Industry, Industrial Processing Companies, Water Supply Industry, Aquaculture and Mariculture Industries, Naval Vessels and the MOD.
Designed for oceanographic deployment up to 5000m however, they have also been used for sampling deep lake sediments.
(Box Corer Deployment)
Double Spade Box Corers - Manufactured in mild steel, galvanized finish with an internal 316 stainless steel box/cabinet and a stainless steel yoke. These are provided with a stand, and lead ballast ingot weights. The following sizes are available. Sampling areas of : 300mm x 300mm x 1m high box cabinet 0.1m sq x 1m high box cabinet 500mm x 500mm x 1.2m high box cabinet
Single Spade Box Corers - Manufactured in mild steel, galvanized finish with a removable stainless steel box cabinet measuring 300mm x 300mm x 300mm high provided with lead ballast ingot weights. (Other box cabinet size measurements are available on request).
(Single Spade Box Corer)
We supply an extensive range of corers, designed for both marine and freshwater use, denoted by (M) or (F).
Multi Corers (M) - Mounted on a mild steel frame, galvanized finish with a 316 stainless steel RAM and tube frame, with stainless steel components and acrylic tubes, holding 4 corer tubes, 500mm in length. (Other versions are available, holding 6, 8 and 10 corer tubes with the option of varying tube lengths. These are mounted on larger frames than that in the photograph).
Gravity Corers (M) - Manufactured in mild steel with varying corer barrel lengths between 1m and 6m, and a range of barrel diameters. Supplied complete with core liners, cutters and catchers. These can also be adapted to be used as Piston corers and supplied with stainless steel releaser mechanisms.
Craib Corer (M) - Manufactured in brass and mounted on a mild steel, galvanized finish frame and supplied with a range of acrylic tubes.
Mini Mackereth Corer (F) - Manufactured in UPVC and aluminum with an acrylic corer tube 1m long, and pneumatic control system. (We can also manufacture bespoke Mackereth pneumatic corers with up to 6m long core tubes).
Jenkin Surface Mud Sampler (F) - Manufactured in aluminum and stainless steel with an acrylic corer tube for water interface sampling.
Livingston Corer (F) - Manufactured in 316 stainless steel, 1m barrel, 54.76mm ID, complete with extension poles and jacking handle.
Liquid Nitrogen Corer (F) - Manufactured in 316 stainless steel, 1.3m long, 54.76mm ID.
Gilson Corer (M and F) - Manufactured in 316 stainless steel and brass with removable, acrylic corer tubes, 300mm and 470mm in length, 55mm ID. Available for rope and pole operation.
Lune Corer (F) - Pole operated, manufactured in brass with acrylic corer tube, 55mm ID and a series of extension poles for deployment.
Intertidal Corer (Marine Coastal) - Manufactured in 316 stainless steel with sampling areas of either 0.01m sq., or 0.1m sq.
Intertidal Box Corer (Marine Coastal) - Manufactured in 316 stainless steel with a sampling area of 0.1m sq.
Giant Gravity Corers and Piston Corers (M) - These items can be manufactured against customers individual specifications. We have manufactured barrel lengths up to 32m and gravity corer weights of up to 10 tons.
We can also provide hydraulic extruder systems for most of our corers.
Designed for large freshwater bodies, estuaries and offshore coastal environments.
Principally used for benthic and epifaunal trawls.
Long Harness Biological Dredge - Manufactured in 316 stainless steel with a sampling area of 200mm in depth, 500mm in width. Provided with chaffer sheets and harness with removable net bags.
Short Harness Biological Dredge - Manufactured in 316 stainless steel with a sampling area of 200mm in depth, 500mm in width. Provided with chaffer sheets and harness with removable net bags.
Naturalists' Dredge - Manufactured in 316 stainless steel, sampling area 100mm high, 305mm wide with removable collection bag, cod end bottles and bridle.
Anchor Dredge - Manufactured in 316 stainless steel with a sampling area of 200mm in depth, 500mm in width. Provided with chaffer sheets and adjustable towing frame, with removable net bags.
We supply an extensive range of Grab samplers designed for the qualitative and quantitative sampling of freshwater and marine sediments.
Van Veen Grabs - Manufactured in 316 stainless steel with hinged access lids in the tops of the buckets and provision for lead ballast weights on both the backs of the buckets and the arms.
(Van Veen Grab)
Our range of Van Veen grabs are available in the following sampling areas 0.025m sq., 0.045m sq., 0.1m sq., 0.2m sq., and 0.3m sq., together with a Double Van Veen (2 x 0.1m sq. Van Veens mounted alongside each other).
Ekman Grab - Manufactured in 316 stainless steel, designed for either rope or pole operation with a sampling area of 225cm sq., complete with access lids and mild steel weights.
Peterson Type Grabs - Manufactured in 316 stainless steel, supplied with lead ballast weights, with sampling areas of 0.05m sq. and 0.1m sq.
Ponar Type Grabs - Manufactured in 316 stainless steel, supplied with lead ballast weights, with sampling areas of 0.05m sq. and 0.1m sq.
Day Grab - Manufactured in 316 stainless steel, with a sampling area of 0.1m sq. The option of lead ballast weights and landing table.
Smith McIntyre - Manufactured in 316 stainless steel with a sampling area of 0.1m sq. The option of lead ballast weights and landing table.
Shipeck Grab - Manufactured in 316 stainless steel with a sampling area of 0.042m sq. The option of a landing table.
Hamon Grab - Manufactured in mild steel, galvanized finish with a 316 stainless steel bucket. Sampling area 0.1m sq., 15L capacity, provided with a stand, with the option of additional lead ballast weights. (Other capacities and sampling area options are available).
(Mini Hamon Grab)
Bucket Sieves - Manufactured in 316 stainless steel with a removable 1000 micron mesh stainless steel gauze base. (Mesh size options are available).
We can also provide sieving tables.
We supply the following items to order as standard products:
Bou Rouch Sampling Pump - Manufactured in UPVC, with a stainless steel probe, collection bag and other ancillary items.
(Bou Rouch Pump)
Modified Surber Sampler - With a sampling area of 305mm x 305mm, manufactured in 316 stainless steel and UPVC, complete with collection bag.
Kick Net Sampler - Supplied with 1000 micron mesh bag (soft material). Other mesh options are available.
(Kick net Sampler)
RUSSIAN PEAT CORER - Manufactured in 316 stainless steel with sampling barrel/chamber lengths of 500mm and 1000mm, ID 54.76mm, provided with aluminum extension poles, T handle and stainless steel jacking handles.
(Peat Corer Open)
(Plankton Net Large)
Mesh sizes are available from 10 micron to 1000 micron.
We also offer a range of Bridles, Depressors, Plankton Net buckets, Closure Mechanisms and Bottles for our range of Nets.
There is also the option of stainless steel towing hoops onto which the net can be clamped, enabling an option of nets to be interchanged onto the same hoop. These are available in 600mm diameter and 1000mm diameter.
Mini Bongo net options are available incorporating the 300mm and 500mm diameter standard nets above, mounted as a pair of nets on a single towing frame.
Secchi Disc manufactured in UVPC as a black and white quadrant, with stainless steel weight and calibrated lowering rope.
Phytoplankton and Zooplankton Examination Accessories
Bogoroff Troughs - Manufactured in acrylic. 2 channel and 6 channel.
(Bogoroff Trough 6 Channel)
Zooplankton Counting Disc - Manufactured in acrylic.
Tubular Plankton Chambers - With stainless steel bases and acrylic tubes. 5ml, 10ml, 15ml and 25ml capacities.
Sedgwick Rafters - Glass and Perspex, 1ml capacity.
The range of Water Samplers we can offer are designed for both freshwater and marine use and are deployed by either a rope or cable and activated using a messenger (unless otherwise stated below).
Ruttner Water Samplers - Manufactured in either brass, stainless steel or PTFE with acrylic bodies, vertical deployment, 1L, 2L and 3L capacity (80mm OD).
(Ruttner Water Sampler)
Van Dorn Water Samplers - Mounted on a stainless steel frame, with UPVC components and acrylic bodies, horizontal and vertical deployment, 1L, 2L and 3L capacity.
(Van Dorn Water Sampler)
Marpet Water Sampler - Manufactured in UVPC with a 500ml capacity, removable glass bottle. Vertical deployment.
(Marpet Water Sampler)
Kemmerer Type Water Sampler - Manufactured in UPVC with clear acrylic body, vertical deployment, 1.5L capacity.
(Kemmerer Water Sampler)
Column Water Sampler - Manufactured in UVPC, obtaining a 10m horizon of water from the water column. Complete with automatic foot valve and closure taps.
(Column Water Sampler)
Bailer (also know as Dipper or Well Sampler) - Manufactured in 316 stainless steel with internal UPVC valves, 250ml capacity, vertical deployment.
Phil Sampler - Pole operated (this does not require a messenger), manufactured in stainless steel, UPVC with a removable 500ml glass collection bottle.
Bank Sampler - Pole operated, manufactured in UPVC, and aluminum with a removable 1L plastic bottle.
Oceanographic and limnological research is becoming more complex as researchers strive to understand and monitor new environmental phenomena.
The increasing development of industrial processes globally, coupled with our historical industrial legacy involving toxic and environmentally hazardous waste bi-products, continue to be an area impacting upon the freshwater and marine environment.
These evolving areas of research require bespoke items of equipment to support the monitoring and sampling programmers. We have, over the years, worked alongside researchers to develop and update various items of equipment to fulfill their specific needs.
(Left, Catamaran; Right, Plastic Debris)
Please see below some examples:
Filter Bed Corer
- Filter Bed Expansion Tool
- Debris Collector
- Vacuum Corer
(Filter Bed Corer)
(Filter Bed Expansion Tool)
We have also manufactured sediment collection systems, re-circulating Flumes for the examination of invertebrates, experimental freshwater mussel hatchery facility, customized many of our Grabs and Water Samplers as well as incorporating systems for filming our Grab Samplers in operation.