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Tank Terminology Guide

New to plastic tanks? Here is what the terms mean.

Materials

TermDefinition
HDPEHigh Density Polyethylene. Standard tank plastic. Excellent chemical resistance. FDA-approved grades available.
XLPECross-Linked Polyethylene. Tougher than HDPE. For aggressive chemicals, diesel, high temps. 15-25% premium.
PPPolypropylene. Used in fittings, valves, couplers. Higher temp tolerance than HDPE.
FRPFiberglass Reinforced Plastic. Higher temp rating. More expensive, brittle on impact.

Specifications

TermDefinition
Specific Gravity (SG)Liquid density vs water. Water = 1.0. A 1.5 SG tank holds liquids 50% heavier than water. Always match or exceed your liquid SG.
NPTNational Pipe Thread. Standard US pipe threading. Tapered threads seal with Teflon tape.
Bulkhead FittingFitting that passes through the tank wall, sealed with gaskets. Drill hole, insert, tighten.
Manway / LidTop opening for filling and access. Measured by diameter (8", 16", 22").
FDA ApprovedResin meets FDA requirements for food and drinking water contact.
NSF 61NSF standard for drinking water materials. More rigorous than FDA.
UV StabilizedUV inhibitors compounded into resin. Not a surface coating.

Tank Types

TermDefinition
Vertical TankUpright cylinder. Small footprint. 10 to 20,000 gallons.
Cone BottomCone bottom for 100% drainage. Requires stand. Chemical mixing.
Inductor TankCone bottom for mixing chemicals into spray systems.
Doorway TankSlim profile fits through 32" doors. Indoor storage.
Horizontal / Leg TankSideways on legs. Transport applications.
Elliptical TankHorizontal with oval cross-section. Lower trailer profile.

Manufacturing

TermDefinition
RotomoldingHeated rotating mold creates seamless one-piece tank.
Parting LineThin ridge where mold halves meet. Normal.

Shipping

TermDefinition
LTLLess Than Truckload. Shared trailer. 3-7 days.
LiftgateHydraulic platform lowers tank to ground. Extra $50-100.
Will CallPick up from nearest plant. No freight.

Questions? Call (866) 418-1777. We speak tank.