Thelco Worthington 953543 Untrimmed Cast Iron Centrifugal Pump Impeller

Brand	Thelco Worthington
MPN	953543
Impeller Type	Closed (shrouded), centrifugal
As-Supplied OD (Untrimmed)	~10 in (untrimmed, as cast)
Required Trim OD	9-5/16 in (per handwritten note on casting)
Material	Gray cast iron
Hub Bore Feature	Keyed bore w/ bolt-circle flange

This is a new (other condition) Thelco / Worthington part number 953543 centrifugal pump impeller, supplied in untrimmed (full) diameter form as handwritten notes on the casting clearly direct the installer to "Trim to 9 5/16" before installing." The impeller is a closed-type design — visible in the side-profile photo are two shroud plates enclosing internal vanes, characteristic of closed centrifugal impellers used for clean-water and industrial process-fluid applications. The casting is gray iron and shows the typical as-cast finish with a machined bore hub featuring a keyway and bolt-circle flange for positive torque transmission on the pump shaft. Worthington (a Dresser Industries / FLOWSERVE lineage brand) and its Thelco product line were widely used in industrial centrifugal pumps across HVAC, water supply, and general industrial service; part number 953543 is associated with that pump family and requires a final OD trim to 9-5/16 inches on a lathe prior to installation to match the specific pump casing clearance.

Product Specifications
Brand	Thelco Worthington
MPN	953543
Impeller Type	Closed (shrouded), centrifugal
As-Supplied OD (Untrimmed)	~10 in (untrimmed, as cast)
Required Trim OD	9-5/16 in (per handwritten note on casting)
Material	Gray cast iron
Hub Bore Feature	Keyed bore w/ bolt-circle flange