How to Ship a Horizontal Directional Drill: HDD Rig Transport Guide

HDD Rig Size Classes and Transport Specifications

HDD rigs are classified by their thrust/pullback force, which correlates directly with machine size and weight. Transport requirements vary dramatically across classes:

Class	Thrust/Pullback	Machine Weight	Transport Width	Transport Height
Mini/Compact	Under 20,000 lbs	5,000–15,000 lbs	5–6 ft	6–8 ft
Utility	20,000–100,000 lbs	15,000–35,000 lbs	6–8 ft	8–10 ft
Mid-Size	100,000–250,000 lbs	35,000–60,000 lbs	8–10 ft	9–11 ft
Maxi-Rig	250,000–1,000,000+ lbs	60,000–100,000+ lbs	8–10 ft	10–13 ft

A utility-class rig like the Vermeer D23x30 weighs approximately 17,000 lbs and ships easily on a flatbed or step deck. A maxi-rig like the Vermeer D500x500 or American Augers DD-440T can weigh 70,000 lbs or more for the main unit alone, requiring an RGN lowboy and separate trailers for the power unit, operator cab, and drill pipe.

Modular Transport for Maxi-Rigs

Large HDD maxi-rigs are typically transported in multiple modules due to their size and weight. A typical maxi-rig transport involves:

• Main drill unit: The primary machine, typically 40 to 45 feet long and weighing 60,000 to 100,000 lbs. Ships on a multi-axle RGN lowboy.
• Power unit / generator: A separate diesel power pack, typically 20 feet long and weighing 30,000 to 40,000 lbs. Ships on a flatbed or step deck.
• Operator cab: A separate control cabin, typically 10 feet long and weighing 7,000 to 10,000 lbs. Ships on a flatbed.
• Drill pipe and tooling: Drill rods, reamers, and tooling ship on a separate flatbed. Drill pipe bundles can weigh 20,000 to 40,000 lbs.
• Mud mixing system: Bentonite mixing and recycling equipment ships on a separate trailer.

A full maxi-rig mobilization can require 4 to 6 separate trailers, making logistics coordination critical for on-time project starts.

Trailer Selection for HDD Rig Transport

• Flatbed: For mini and compact rigs under 48,000 lbs and within legal dimensions. Also used for power units, operator cabs, and drill pipe.
• Step Deck: For utility-class rigs where the machine height would push the total load over 13'6" on a flatbed.
• RGN Lowboy: Required for mid-size and maxi-rig main units. The low deck height (18–24 inches) is essential for tall machines and heavy loads.
• Multi-axle RGN: Required for maxi-rig main units exceeding 80,000 lbs. Multi-axle configurations distribute weight to comply with bridge formula requirements.

Permit Requirements for HDD Rig Shipping

Permit requirements depend on the rig class:

• Mini and compact rigs: Typically no permits required — within legal limits in most states.
• Utility-class rigs: May require overweight permits if the combined trailer and rig GVW exceeds 80,000 lbs. Width permits if the rig exceeds 8'6".
• Mid-size and maxi-rigs: Almost always require oversize and overweight permits. Maxi-rig main units may require superload permits with engineering route surveys and escort vehicles.

Loading and Securement Considerations

HDD rigs have specific loading requirements:

• The drill frame must be secured at designated tie-down points — typically the main frame rails and front/rear lifting points.
• The drill head and carriage must be secured in the transport position (fully retracted).
• Hydraulic hoses and electrical connections must be secured to prevent damage during transport.
• Drill pipe must be bundled and secured separately — loose pipe is a serious safety hazard.

IronHaul Logistics specializes in HDD rig transport for underground utility contractors. Whether you're moving a single utility rig or coordinating a full maxi-rig mobilization across multiple trailers, our team handles permitting, escort coordination, and multi-trailer logistics. Call (208) 495-2260, email [email protected], or request a free quote online.