Story and photos by Kristen Cart
Tucked into a nest of grain bins in the west-central Iowa town of Churdan is an old original elevator built by Tillotson Construction Company of Omaha, Neb. The annex hard by its side also boasts the Tillotson name.
It is immediately obvious that the old Tillotson structure has been updated at some time in the past with a leg that extends above the headhouse, thereby keeping the machinery most prone to overheating far from accumulations of grain dust.
The annex beside it shows signs of cracking. Stress cracks are an old enemy of elevators, a problem which eventually spelled the demise of the Churdan elevator’s twin at Glidden, Iowa, and also the Mayer-Osborn elevator at Maywood, Kan.
Manhole covers along the side declare that the annex was built by Tillotson Construction in 1955.
An elevator built by Quad States was added to the Farmers Cooperative complex some years later. (Its trademark stepped headhouse is curved only at the outside margins, a usually reliable indicator of a Quad States design. A manhole cover dated 1969 boasts its provenance.)
A white-painted metal bin, served by the Tillotson elevator headhouse, was also added to the site to increase storage capacity.
After demolition of two faulty bins in 2013, the concrete remnants were bulldozed into the center of an empty lot across from the co-op office.
A large-capacity shiny metal bin across the street completes the scene.
We are fortunate to have the specifications for the Churdan elevator, which is an early example built in 1949, and for its 198,960-bushel annex. The elevator specifications are detailed below.
The “Churdan Plan” was used for a number of Tillotson elevators, including Glidden, Sanborn, Gilmore City, and Thompson, Iowa; Greenwood and Fairfield, Neb.; and Montevideo, Minn. The construction of elevators using this plan spanned from 1949 to 1952. Specifications varied according to an individual customer’s requirements.
The “Churdan Plan” consisted of four 14 1/2-foot-diameter bins, 100 feet tall, with a 13-by-17-foot driveway and eight bins over the driveway. It had a 13-foot spread. Notations in the company record said “bin split for drier” and “16 bins and dust bin.”
Capacity per plans (with Dock): 102,000 bushels
Capacity per foot of height: 1,318 bushels
Reinforced concrete per plans (total): 1,083 cubic yards
Plain concrete (hoppers): 25 cubic yards
Reinforcing steel per plans (including jack rods): 57.72 tons
Average steel per cubic yard reinforced concrete: 106.5 pounds
Steel and reinforced concrete itemized per plans:
Below main slab: 3,133 pounds steel, 29 cubic yards concrete
Main slab: 15,937 pounds steel, 113 cubic yards concrete
Drawform walls: 73,405 pounds steel, 760 cubic yards concrete
Work and Driveway floor (including columns): 3,370 pounds steel, 26 cubic yards concrete
Deep bin bottoms: 3,480 pounds steel, 19 cubic yards concrete
Overhead Bin bottoms: 3,752 pounds concrete, 23 cubic yards concrete
Bin roof (or garner): 3,060 pounds steel, 30 cubic yards concrete
Scale floor (complete): 186 pounds steel, 3 cubic yards concrete
Cupola walls: 3,481 pounds steel, 35 cubic yards concrete
Distributor floor: 886 pound steel, 7 cubic yards concrete
Cupola roof: 1,129 pounds steel, 9 cubic yards concrete
Misc. (boot, leg, head, track sink, steps, etc.): 1,036 pounds steel, 20 cubic yards concrete
Attached driveway: 600 pounds steel, 9 cubic yards concrete (driveway extension)
Main slab dimensions (drive length first dimension): 48′ x 48′
Main slab area (actual outside on ground): 2,270 square feet
Weight reinforced (total) concrete (4000 pounds per cubic yard plus steel): 2,224 tons
Weight plain concrete (hoppers 4000 pounds per cubic yard): 50 tons
Weight hopper fill sand (3000 pounds per cubic yard): 360 tons
Weight of grain (at 60 pounds per bushel): 3,060 tons
Weight of structural steel and machinery: 15 tons
Gross weight loaded: 5,709 tons
Bearing pressure: 2.52 tons per square foot
Main slab thickness: 18″
Main slab steel: straight 1 1/4″ square at 10″ o. c. spacing
Tank steel and bottom (round tanks): 3/8″ at 8″ o. c. spacing
Lineal feet of drawform walls: 440 excluding extension
Height of drawform walls: 90′
Pit depth below main slab: 12’0″
Cupola dimensions (outside width x length x height): 15′ x 32 1/3′ x 22′
Pulley centers: 115.67′
Number of legs: 1
Distributor floor: yes
Track sink: yes
Full basement: yes
Electrical room: yes
Driveway width clear: 13′
Dump grate size: 2 at 9′ x 5 1/2′ and 9′ x 15′
Column under tanks size: 16″ square
Boot legs and head: concrete
Boot pulley: 60″ x 14″ x 2 3/16″
Head pulley: 60″ x 14″ x 3 15/16″
R.P.M. Head pulley: 44
Belt: 272′, 14″ 6 ply Calumet
Cups: 12″ x 6″ at 9″ o. c. spacing
Head drive: Howell 30 horsepower [3 circled here]
Theoretical leg capacity (cup manufacturers rating): 6,540 bushels per hour
Actual leg capacity (80% of theoretical rating): 5,230 bushels per hour
Horsepower required for leg (based on above actual capacity plus 15% for motor): 19.9 horsepower
Man lift: 2 horsepower Ehr.
Load out scale: 10 Bu. Rich.
Load out spout: 8 1/4″ w.c.
Cupola spouting: 10″ diameter 14 ga.
Truck lift: 7 1/2 horsepower Ehr.
Dust collector system: Fan to bin
Driveway doors: 2 overhead rolling
Split bin for dryer