Convey product in a completely sealed system. The sprocket drive in our tubular drag conveyors slowly pulls a heavy-duty chain through a fully enclosed pipe. As the chain moves your material through the pipe there is no chance for dusting, explosions or contamination issues.
Use less energy than other conveyors. The low-horsepower motor produces the slow, steady drag that cuts your energy costs when conveying powders or bulk solids.
Move challenging materials. Our tubular drag conveyors handle high-moisture ingredients and abrasive, blended, friable, easy-to-compact or smear products without compromising quality or efficiency.
One conveyor does the work of several. A modular design means we can configure our tubular drag conveyors to move your product vertically, horizontally, at any angle and around corners. Need more than one inlet/outlet in your bulk material handling process? Add as many as you need.
The fundamental operation of tubular drag conveyors involves a chain with flights that pull material through a sealed pipe circuit. They operate at high torque/low speed, and their capacity is determined by the diameter of the flight and the speed at which the chain assembly can be pulled through the pipe. Tubular Drag Conveyors are sealed to upstream and downstream equipment by a hard flange or a flexible sleeve. The layout of these conveyors allows for pipe bends, multiple inlet and discharge points, and routing through multiple planes and in any direction.
All of our tubular drag conveyors are customized to fit the specific bulk material handling needs of your application and facility.
Hapman’s custom-built tubular drag conveying systems move some of the toughest products up to hundreds of feet: from hardened steel shot to bacon grease waste, from fishmeal and bones to explosive materials. Our expert consultants and engineers can spec out and build a system based on your specific bulk material handling needs. Paths are virtually limitless and multiple inlets and outlets are possible with our Tubular Drag Conveyors.
In addition to optimum conveying, our sealed Tubular Drag Conveyors offer:
Improve product flow when you install mechanical vibration. An offset weight and hammer system taps on the tops of flights to dislodge material.
Fully discharge material with Hapman’s exclusive, self-cleaning discharge gates. Unlike flat gates in other conveyors, ours are rounded to the shape of the pipe so there is no place for your product to become trapped.
The chart below represents the optimum convey rate for most materials based on average capacity in cubic feet/minute and pipe size. Actual capacities vary depending on the material type, its abrasiveness and flow character.
Pipe Casing Diameter & Material Options
3 in (76 mm) to 12 in (300 mm) diameter
Chain Material Options
Tivar® H.O.T. premium UHMW polyethylene
Maximum Conveyance Distance
85 ft vertically (26 m)
400 ft horizontally (122 m)
Maximum Conveyance Speed
Convey up to 50 cfm (1.416 cmm)
During your evaluation of tubular drag conveyors to determine the best match your bulk material handling needs, you will need to assess the cable vs. chain comparison. While every application has different requirements and measurements for value, we present some of the most common differences between the two conveying types for your review.
You never have to worry about selecting the correct chain and flight assembly for your bulk material handling application. We will work with you to determine the equipment that best suits your specific needs. We do not believe in a one-size-fits-all approach to conveying material.
As confirmed by our more than 70 years of experience and our testing of over 2,600 distinct materials, mechanical conveying is most effective when the right combination of chain type and flight material is applied to the characteristics of the conveyed material. That’s why we offer the most comprehensive array of chain and flight options in the industry to provide you the best conveying equipment for your application. The options range from:
Flight material options range from UHMW polyethylene, glass reinforced polyethylene, cast steel, and iron. Each is engineered for exceptional conveying properties when evaluating bulk density, temperature, and other handling and material characteristics.
The most common chain and flight assembly is the sealed pin with UHMW polyethylene flights. This configuration of chain type and flight material provides the longest life for the flight and least maintenance for the chain in most material conveying applications. The sealed pin chain is engineered specifically for moving dry material of various size and bulk density. The main advantages are:
Product Brochure: Tubular Drag Conveyors
Application Review: Food Processor Replaces Aeromechanical Conveyor with Hapman Tubular Drag System Eliminating Contamination, Clogging, Jamming & Shutdowns
Application Review: Biotech Lab Handling Dirty Mice Bedding From Cages with Cleaning Disposal System
Application Review: Portable Bulk Bag Unloading – Chemical Company Charging Hoppers with Limestone Combining with Helix® Flexible Screw Conveyor
Application Review: Tubular Drag Conveying System – Mining Operation Handles and Conveys Ammonium Nitrate Reducing Degradation
Application Review: Tubular Drag Conveying System – Tire Manufacturer with Dust-Free Multiple Inlet System Handling Carbon Black
Case Study: A Manufacturer of Explosives Seeks to Safely and Effectively Off-Load Railcars of Corrosive Bulk Material
Case Study: Human Health Benefits, Operational Efficiencies, Increased Productivity, Cost Improvements
Case Study: The Genentech South San Francisco Campus Achieves Cost Savings and Operating Efficiency By Applying the Right Waste Bedding Handling System
Case Study: Tubular Drag Conveying Technology – A Cost-Effective and Energy Saving Alternative to Pneumatic Conveying
Case Study: Stillwater Mining Improves Smelting Efficiency and Yield, Eliminates Dust with Tubular Drag Conveyor
Case Study: Fiber By-Products Reduces Maintenance, Dust and Reprocessing of End Product with Tubular Drag Conveyor
Case Study: The University of California San Francisco, Laboratory Animal Resource Center (LARC) Finds Significant Cost Savings in Effective Handling of Waste Bedding Material
Case Study: Uniformed Services University Health Science Center for Laboratory Animal Medicine Overcomes a Severe Bedding Handling Challenge
Case Study: Aluminum Casting Company Leverages Custom-Built Hapman Equipment to Create a Cleaner, Quieter Foundry
Tech Brief: Selecting A Conveyor for Effectively Moving Bulk Materials
Tech Brief: The Evaluation of Tubular Drag Conveyor Types
Tech Brief: Tubular Drag Technology for the Conveyance of Powder and Bulk Solids
Tech Brief: Tubular Drag Conveying – A Cost-Effective, Energy-Saving Alternative to Pneumatic Conveying