Download: Launder Cover – AL- SECTION 13221





A. Provide aluminum launder covers and appurtenances as indicated and specified.

B. Launder covers shall be the product of one manufacturer.

Please list all tanks where covers are required and clearly identify on the contract drawings provided:



A. American Society for Testing and Materials (ASTM) Publications:

1. B209: Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate

2. B221: Standard specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Shapes and Tubes

3. F593: Standard Specifications for Stainless Steel Bolts, Hex Cap Screws and Studs

4. F594: Standard Specification for Stainless Steel Nuts.


A. The Contractor shall conform to the seismic design requirements for this project and for the work of this specification sect ion.

B. Provide all equipment bases, anchorage, supports and foundations designed in accordance with the seismic requirement s indicated and specified.

C. Additionally, provide a certification for all equipment signed by a registered structural engineer registered in the state where covers are installed, stating that computations were performed and that all components have been sized for the seismic forces specified and indicated. This certification is provided in the Manufacturer’s Equipment Certification.


A. Submit the following in accordance with submittal procedures.

1. Certified shop and erection drawings. Contractor shall submit electronic files of the proposed equipment in the capacity, size, and arrangement as indicated and specified.

a. Electronic files shall conform to the following minimum requirements:

1) Electronic Files: AutoCAD latest version, drawn to scale.

2) Submit electronic files as part of the Shop Drawing submittal.

3) Drawings shall include plan views, sectional views, title block, Tag Numbers, Parts List (identifying each component), dimensions, connection sizes and types and all details of all related items. In cases where certain information is proprietary and is omitted, provided a statement indicating that the information is proprietary and is being omitted.

4) Drawings shall be in conformance with all other requirements as specified in this specification.

2. Method of attachment, size of fasteners and weights of each section

3. Shop drawing data for accessory items.

4. Certified setting plans, with tolerances, for anchor bolts.

5. Listing of reference installations as specified with contact names and telephone numbers.

6. Shop and field inspection reports.

7. Shop test results: Certified test reports of the physical and mechanical properties as specified herein.

8. Recommendations for short and long-term storage.

9. Special tools.

10. The latest ISO 9001 series certification or quality system plan.


A. Covers shall be the product of one manufacturer.

B. Covers shall be manufacturer’s standard cataloged product and modified to provide compliance with the drawings, specifications and the service conditions specified and indicated.

C. Shop tests as specified.

D. Warranty: Provide a one (1) year warrantee from material and workmanship defects.

E. Coordination: Cover manufacturer shall coordinate the fabrication of the covers with the contractor and clarifier manufacturer in regards to the clarifier mechanism, scum collection and launder and channel configurations.

F. Provide the following certificates related to the supply, installation and operation of the equipment specified herein in accordance with manufactures certificates:

1. Manufacturer’s Equipment Certification
2. Equipment Installation Certification
3. Equipment Operation Warranty


A. Provide in accordance with requirements.

B. Shipping:

1. All systems, sub-systems and structures shall be shop fabricated and assembled into the largest practical size suitable for transporting.


A. Submit Operation and Maintenance Manuals as specified in close out submittal.



A. RPS Engineering Elgin, Illinois 60123


A. Provide the launder covers consisting of a system of extruded aluminum panels that are attached together to form a continuous cover over the launder trough, weir and scum baffle within the tank.

1. Provide the cover extending over the trough and weir to a point immediately inside the scum baffle so long as the cover does not interfere with the sweep arm.

2. Individual sections: fitted to follow the curvature of the tank.

B. Provide the cover designed such that adjacent panels fit together and the completed cover, when installed, forms a rigid structure.

C. Provide covers designed and manufactured to inhibit incident sunlight from striking the surfaces of the launder and weir.

D. Covers shall have an integrated bi-directional slip resistant surface. This surface shall not be achieved by the use of paint or adhesive tapes.

E. Covers shall allow for thermal expansion and contraction

F. Provide the cover designed to open away from or towards the operator as shown on the contract drawings.

G. Covers weight shall not exceed 75 lbs. Each panel shall be easy to lift with the lifting force no greater than the dead weight of the panel.

H. Design deflection of all structural members and cover panels shall be limited to U240 with L equal to the short span of the components when supporting the total dead and live load conditions.

I. Provide a means of limiting the travel of the hinged cover section, in the form of a restraint of Type 316 stainless steel cable.

J. Covers with inspection hatches or cleanout doors are not acceptable.

K. Provide covers to support the cover in such a manner that the panels are held in place, with the panels hinged to provide access to the launder and weir for inspection and maintenance.

L. Where the circumference of the trough is interrupted by a bridge-support or another obstacle, provide a fixed panel(s) over the trough beneath the support such that the surface of the cover is continuous around the entire tank.

M. Provide the cover system designed to withstand wind and snow loads for the plant location and support a 250 lb. person when walkable cover is required.


A. Aluminum Launder Cover
a. Structural frame/support: ASTM B221 6061-T6 aluminum
b. Cover panels/hatches: ASTM B209 aluminum, 6061-T6 aluminum or 6063-T6 aluminum or equal
c. Fasteners: Type 316 or 304 stainless steel. ASTM F593, ASTM F594
d. Expansion Anchor Bolts: Type 316 or 304 stainless steel. ASTM F593, ASTM F594



A. Install items in accordance with approved shop drawings, manufacturer’s printed instruction s and as indicated.

B. Contractor to field verify dimensions prior to installing the covers.

C. Provide a mechanical and replaceable seal to isolate the cover perimeter and aluminum supports from the concrete wall.

• Bare Aluminum shall not be installed against existing concrete
• Coat surfaces in contact with dissimilar materials.

D. Provide adjacent baffle panels fastened together using 14-in bolts, 2 flat washers, lock washer, and hex nut. All hardware Type 316 stainless steel.

E. The covers shall extend completely around the tank and shall be level, rigid and free of sway that could work anchors loose or cause undue wear.


A. Provide in accordance with Section_________ CLOSEOUT PROCEDURES.