Unskirted Storage Silos

Economical, Versatile Storage for Outside or In-Plant Use

Whether you need outside or in-plant bulk storage, a BROCK® Bulk Storage System offers a versatile line of economical bolted-steel hopper-bottom silos in the capacities and features you need today – in a silo that will allow you to grow into tomorrow.

Storage Capacities

35 to 6,800 cubic feet (1 to 193 cubic meters)

Silo Diameters

6 to 18 feet (1.8 to 5.5 meters)

Photos & Videos:

Features

Storage Capacities to Fit the Needs of Many Operations

Capacities range from 35 through 6,800 cubic feet (1 through 193 cubic meters). Silo diameters range from 6 to 18 feet (1.8 to 5.5 meters).

High-Strength Roof

The sturdy, low-profile (10-degree slope) roof has a 22-inch (56 cm) fill opening and 12-inch (305 mm) discharge opening with 16×16-inch (41×41 cm) universal flange.

Your Choice of 45° or 60° Center Draw Unloading Hoppers

Variety of Safety and Access Options

Unskirted silos are available with optional safety cages, lockable doors and crosswalks designed to meet OSHA specifications.

Other options include:

Rooftop perimeter guard and toe board
Manholes
Pressure relief valves
View windows

Specifications

Unskirted Storage Silo Capacities:

All Diameters 6 ft. (1.8 m) Diameter 9 Ft. (2.7 m) Diameter 12 Ft. (3.7 m) Diameter 15 Ft. (4.6 m) Diameter 18 Ft. (5.5 m) Diameter Unskirted Storage Silos Specifications

Unskirted Storage Silos

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
60° Hopper Angle
6 ft. (1.8 m)	C45-00601	124	4	113	3	10.2	3.1
6 ft. (1.8 m)	C45-00602	199	6	188	5	12.8	3.9
6 ft. (1.8 m)	C45-00603	273	8	262	7	15.5	4.7
6 ft. (1.8 m)	C45-00604	348	10	337	10	18.2	5.5
6 ft. (1.8 m)	C45-00605	423	12	412	12	20.8	6.3
6 ft. (1.8 m)	C45-00606	497	14	486	14	23.5	7.2
45° Hopper Angle
9 ft. (2.7 m)	C45-00932	439	12	385	11	13.0	4.0
9 ft. (2.7 m)	C45-00933	608	17	554	16	15.8	4.8
9 ft. (2.7 m)	C45-00934	777	22	723	20	18.5	5.6
9 ft. (2.7 m)	C45-00935	946	27	892	25	21.2	6.5
9 ft. (2.7 m)	C45-00936	1,115	32	1,061	30	23.8	7.3
9 ft. (2.7 m)	C45-00937	1,284	36	1,230	35	26.4	8.0
9 ft. (2.7 m)	C45-00938	1,453	41	1,399	40	29.0	8.8
9 ft. (2.7 m)	C45-00939	1,622	46	1,568	44	31.7	9.7
9 ft. (2.7 m)	C45-009310	1,791	51	1,737	49	34.3	10.5
9 ft. (2.7 m)	C45-009311	1,960	56	1,906	54	37.0	11.3
60° Hopper Angle
9 ft. (2.7 m)	C45-00902	514	15	460	13	16.0	4.9
9 ft. (2.7 m)	C45-00903	684	19	630	18	18.6	5.7
9 ft. (2.7 m)	C45-00904	854	24	800	23	21.3	6.5
9 ft. (2.7 m)	C45-00905	1,019	29	965	27	24.0	7.3
9 ft. (2.7 m)	C45-00906	1,189	34	1,135	32	26.6	8.1
9 ft. (2.7 m)	C45-00907	1,359	38	1,305	37	29.3	8.9
9 ft. (2.7 m)	C45-00908	1,529	43	1,475	42	31.9	9.7
9 ft. (2.7 m)	C45-00909	1,699	48	1,645	47	34.6	10.5
9 ft. (2.7 m)	C45-009010	1,869	53	1,815	51	37.3	11.4
45° Hopper Angle
12 ft. (3.7 m)	C45-01232	803	23	662	19	14.9	4.5
12 ft. (3.7 m)	C45-01233	1,102	31	961	27	17.6	5.4
12 ft. (3.7 m)	C45-01234	1,400	40	1,259	36	20.3	6.2
12 ft. (3.7 m)	C45-01235	1,698	48	1,557	44	22.9	7.0
12 ft. (3.7 m)	C45-01236	1,997	57	1,856	53	25.6	7.8
12 ft. (3.7 m)	C45-01237	2,295	65	2,154	61	28.3	8.6
12 ft. (3.7 m)	C45-01238	2,593	73	2,452	69	31.0	9.4
12 ft. (3.7 m)	C45-01239	2,892	82	2,751	78	33.6	10.2
12 ft. (3.7 m)	C45-012310	3,190	90	3,049	86	36.3	11.1
12 ft. (3.7 m)	C45-012311	3,489	99	3,348	95	39.0	11.9
60° Hopper Angle
12 ft. (3.7 m)	C45-01202	966	27	825	23	18.8	5.7
12 ft. (3.7 m)	C45-01203	1,265	36	1,124	32	21.5	6.6
12 ft. (3.7 m)	C45-01204	1,563	44	1,422	40	24.1	7.3
12 ft. (3.7 m)	C45-01205	1,861	53	1,720	49	26.8	8.2
12 ft. (3.7 m)	C45-01206	2,160	61	2,019	57	29.5	9.0
12 ft. (3.7 m)	C45-01202	2,459	70	2,318	66	32.2	9.8
12 ft. (3.7 m)	C45-01208	2,758	78	2,617	74	34.8	10.6
12 ft. (3.7 m)	C45-01209	3,057	87	2,916	83	37.5	11.4
12 ft. (3.7 m)	C45-012010	3,356	95	3,215	91	40.2	12.3
12 ft. (3.7 m)	C45-012011	3,655	103	3,514	100	42.9	13.1
45° Hopper Angle
15 ft. (4.6 m)	C45-01532	1,386	39	1,096	31	16.7	5.1
15 ft. (4.6 m)	C45-01533	1,854	52	1,564	44	19.3	5.9
15 ft. (4.6 m)	C45-01534	2,323	66	2,033	58	22.0	6.7
15 ft. (4.6 m)	C45-01535	2,792	79	2,502	71	24.7	7.5
15 ft. (4.6 m)	C45-01536	3,261	92	2,971	84	27.3	8.3
15 ft. (4.6 m)	C45-01537	3,730	106	3,440	97	30.0	9.1
15 ft. (4.6 m)	C45-01538	4,199	119	3,909	111	32.7	10.0
15 ft. (4.6 m)	C45-01539	4,668	132	4,378	124	35.4	10.8
60° Hopper Angle
15 ft. (4.6 m)	C45-01502	1,734	49	1,444	41	21.6	6.6
15 ft. (4.6 m)	C45-01503	2,200	62	1,910	54	24.3	7.4
15 ft. (4.6 m)	C45-01504	2,666	75	2,376	67	26.9	8.2
15 ft. (4.6 m)	C45-01505	3,132	89	2,842	80	29.6	9.0
15 ft. (4.6 m)	C45-01506	3,599	102	3,309	94	32.3	9.8
15 ft. (4.6 m)	C45-01507	4,065	115	3,775	107	34.9	10.6
15 ft. (4.6 m)	C45-01508	4,531	128	4,241	120	37.6	11.5
45° Hopper Angle
18 ft. (5.5 m)	C45-01832	2,120	60	1,600	45	19.0	5.8
18 ft. (5.5 m)	C45-01833	2,791	79	2,271	64	21.7	6.6
18 ft. (5.5 m)	C45-01834	3,463	98	2,943	83	24.3	7.4
18 ft. (5.5 m)	C45-01835	4,134	117	3,614	102	27.0	8.2
18 ft. (5.5 m)	C45-01836	4,805	136	4,285	121	29.7	9.1
18 ft. (5.5 m)	C45-01837	5,476	155	4,956	140	32.4	9.9
18 ft. (5.5 m)	C45-01838	6,148	174	5,628	159	35.0	10.7
18 ft. (5.5 m)	C45-01839	6,820	193	6,300	178	37.3	11.4

Notes

*Approximate Usable Storage Capacity with 30° Angle of Repose

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
60° Hopper Angle
6 ft. (1.8 m)	C45-00601	124	4	113	3	10.2	3.1
6 ft. (1.8 m)	C45-00602	199	6	188	5	12.8	3.9
6 ft. (1.8 m)	C45-00603	273	8	262	7	15.5	4.7
6 ft. (1.8 m)	C45-00604	348	10	337	10	18.2	5.5
6 ft. (1.8 m)	C45-00605	423	12	412	12	20.8	6.3
6 ft. (1.8 m)	C45-00606	497	14	486	14	23.5	7.2

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
45° Hopper Angle
9 ft. (2.7 m)	C45-00932	439	12	385	11	13.0	4.0
9 ft. (2.7 m)	C45-00933	608	17	554	16	15.8	4.8
9 ft. (2.7 m)	C45-00934	777	22	723	20	18.5	5.6
9 ft. (2.7 m)	C45-00935	946	27	892	25	21.2	6.5
9 ft. (2.7 m)	C45-00936	1,115	32	1,061	30	23.8	7.3
9 ft. (2.7 m)	C45-00937	1,284	36	1,230	35	26.4	8.0
9 ft. (2.7 m)	C45-00938	1,453	41	1,399	40	29.0	8.8
9 ft. (2.7 m)	C45-00939	1,622	46	1,568	44	31.7	9.7
9 ft. (2.7 m)	C45-009310	1,791	51	1,737	49	34.3	10.5
9 ft. (2.7 m)	C45-009311	1,960	56	1,906	54	37.0	11.3
60° Hopper Angle
9 ft. (2.7 m)	C45-00902	514	15	460	13	16.0	4.9
9 ft. (2.7 m)	C45-00903	684	19	630	18	18.6	5.7
9 ft. (2.7 m)	C45-00904	854	24	800	23	21.3	6.5
9 ft. (2.7 m)	C45-00905	1,019	29	965	27	24.0	7.3
9 ft. (2.7 m)	C45-00906	1,189	34	1,135	32	26.6	8.1
9 ft. (2.7 m)	C45-00907	1,359	38	1,305	37	29.3	8.9
9 ft. (2.7 m)	C45-00908	1,529	43	1,475	42	31.9	9.7
9 ft. (2.7 m)	C45-00909	1,699	48	1,645	47	34.6	10.5
9 ft. (2.7 m)	C45-009010	1,869	53	1,815	51	37.3	11.4

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
45° Hopper Angle
12 ft. (3.7 m)	C45-01232	803	23	662	19	14.9	4.5
12 ft. (3.7 m)	C45-01233	1,102	31	961	27	17.6	5.4
12 ft. (3.7 m)	C45-01234	1,400	40	1,259	36	20.3	6.2
12 ft. (3.7 m)	C45-01235	1,698	48	1,557	44	22.9	7.0
12 ft. (3.7 m)	C45-01236	1,997	57	1,856	53	25.6	7.8
12 ft. (3.7 m)	C45-01237	2,295	65	2,154	61	28.3	8.6
12 ft. (3.7 m)	C45-01238	2,593	73	2,452	69	31.0	9.4
12 ft. (3.7 m)	C45-01239	2,892	82	2,751	78	33.6	10.2
12 ft. (3.7 m)	C45-012310	3,190	90	3,049	86	36.3	11.1
12 ft. (3.7 m)	C45-012311	3,489	99	3,348	95	39.0	11.9
60° Hopper Angle
12 ft. (3.7 m)	C45-01202	966	27	825	23	18.8	5.7
12 ft. (3.7 m)	C45-01203	1,265	36	1,124	32	21.5	6.6
12 ft. (3.7 m)	C45-01204	1,563	44	1,422	40	24.1	7.3
12 ft. (3.7 m)	C45-01205	1,861	53	1,720	49	26.8	8.2
12 ft. (3.7 m)	C45-01206	2,160	61	2,019	57	29.5	9.0
12 ft. (3.7 m)	C45-01202	2,459	70	2,318	66	32.2	9.8
12 ft. (3.7 m)	C45-01208	2,758	78	2,617	74	34.8	10.6
12 ft. (3.7 m)	C45-01209	3,057	87	2,916	83	37.5	11.4
12 ft. (3.7 m)	C45-012010	3,356	95	3,215	91	40.2	12.3
12 ft. (3.7 m)	C45-012011	3,655	103	3,514	100	42.9	13.1

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
45° Hopper Angle
15 ft. (4.6 m)	C45-01532	1,386	39	1,096	31	16.7	5.1
15 ft. (4.6 m)	C45-01533	1,854	52	1,564	44	19.3	5.9
15 ft. (4.6 m)	C45-01534	2,323	66	2,033	58	22.0	6.7
15 ft. (4.6 m)	C45-01535	2,792	79	2,502	71	24.7	7.5
15 ft. (4.6 m)	C45-01536	3,261	92	2,971	84	27.3	8.3
15 ft. (4.6 m)	C45-01537	3,730	106	3,440	97	30.0	9.1
15 ft. (4.6 m)	C45-01538	4,199	119	3,909	111	32.7	10.0
15 ft. (4.6 m)	C45-01539	4,668	132	4,378	124	35.4	10.8
60° Hopper Angle
15 ft. (4.6 m)	C45-01502	1,734	49	1,444	41	21.6	6.6
15 ft. (4.6 m)	C45-01503	2,200	62	1,910	54	24.3	7.4
15 ft. (4.6 m)	C45-01504	2,666	75	2,376	67	26.9	8.2
15 ft. (4.6 m)	C45-01505	3,132	89	2,842	80	29.6	9.0
15 ft. (4.6 m)	C45-01506	3,599	102	3,309	94	32.3	9.8
15 ft. (4.6 m)	C45-01507	4,065	115	3,775	107	34.9	10.6
15 ft. (4.6 m)	C45-01508	4,531	128	4,241	120	37.6	11.5

Diameter Feet (Meters)	Model Number	Approx. Capacity Maximum Cu. Ft.	Approx. Capacity Maximum M³	Usable Capacity Cu. Ft.*	Usable Capacity M³*	Height To Lid Feet	Height To Lid Meters
45° Hopper Angle
18 ft. (5.5 m)	C45-01832	2,120	60	1,600	45	19.0	5.8
18 ft. (5.5 m)	C45-01833	2,791	79	2,271	64	21.7	6.6
18 ft. (5.5 m)	C45-01834	3,463	98	2,943	83	24.3	7.4
18 ft. (5.5 m)	C45-01835	4,134	117	3,614	102	27.0	8.2
18 ft. (5.5 m)	C45-01836	4,805	136	4,285	121	29.7	9.1
18 ft. (5.5 m)	C45-01837	5,476	155	4,956	140	32.4	9.9
18 ft. (5.5 m)	C45-01838	6,148	174	5,628	159	35.0	10.7
18 ft. (5.5 m)	C45-01839	6,820	193	6,300	178	37.3	11.4