The Castair Base Mount Top Plate 13x40 (BM13X40) is a structural mounting component sized at 13 inches by 40 inches, used as the top plate in a Castair compressor base mount assembly. It provides the primary mounting surface for the motor and pump assembly on tank-mounted reciprocating compressor configurations, sitting above the tank saddle and below the compressor pump and motor.
What a Base Mount Top Plate Does
In a tank-mounted reciprocating compressor, the motor and pump do not bolt directly to the tank. They mount to a base plate assembly that spans the top of the tank saddle. The top plate is the flat structural member that accepts the motor mounting feet and pump mounting bolts. It carries the dynamic loads from the running compressor — the vibration, torque reactions, and weight — and distributes them into the tank structure.
When this plate fails — through corrosion, cracking, or physical damage — you need an exact-size replacement to restore the mounting geometry. The BM13X40 is the correct replacement for Castair units built on the 13" x 40" base mount specification.
Specifications
- SKU: BM13X40
- Dimensions: 13" x 40"
- Component Type: Base Mount Top Plate
- Category: Major Components — Tanks
- Manufacturer: Cast Air (Castair)
Key Features
- 13" x 40" Dimensions: Correct fit for Castair compressors built on the 13x40 base mount platform — larger than BM12.5x32, smaller than BM17x44
- Structural Integrity: Built to carry the mounting loads of motor and pump assemblies through continuous-duty compressor operation
- OEM Replacement: Correct Castair part number for this base mount size — matches original mounting hole patterns and material specifications
Applications
- Replacement base mount top plate for Castair compressors built on 13" x 40" base mounts
- Compressor rebuilds and refurbishments where the base mount has corroded or been damaged
- Industrial compressor repair where maintaining OEM mounting geometry is required
Base Mount Size Reference
Castair makes base mount top plates in multiple sizes to match different compressor configurations: BM9.5x25 (9.5" x 25"), BM12.5x32 (12.5" x 32"), BM13X40 (13" x 40"), BM17x44 (17" x 44"). Match the plate dimensions to your existing base mount. Call 866-217-0063 if you need help identifying which size your compressor uses.
Why Buy From OEM Diagnostic Tools?
We have been supplying compressor structural components and parts to shops and industrial buyers since 2016. We stock Castair base mount components and can verify the correct size for your unit before you order. Free shipping on qualifying orders, full manufacturer warranty, and direct support at 866-217-0063.
Call 866-217-0063 for quick answers and help!
