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Design guide for drop-in replacement parts
What has to match for a replacement pump or part to fit without modifying the machine: mounting, shaft, ports, rotation and control.
A drop-in replacement is defined by five things, and all five have to match. The mounting flange and pilot diameter fix how the pump sits on the machine. The shaft, its spline or key and its length fix how it couples to the drive. The port sizes, thread forms and positions fix the pipework. The rotation fixes whether it will pump at all. The control type fixes whether the machine's existing signals will do anything.
Buyers usually check the first three and assume the last two, which is where most wrong deliveries come from. Rotation in particular is easy to get wrong on a rebuilt machine, because a pump may have been replaced earlier with the opposite hand and the pipework quietly re-routed to suit.
When we quote a replacement we confirm all five against the code you supply, and where the original is obsolete we say which of the five we are matching exactly and which we are matching by equivalence. That distinction is the useful part of a quotation and is usually the part that is left out.
Specifications
| Must match | Mounting, shaft, ports, rotation, control |
|---|---|
| Most common error | Rotation on a previously rebuilt machine |
| We state | Which points match exactly and which match by equivalence |
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Send us the model code and we will quote
Tell us the code stamped on the pump, or send a photograph of the nameplate. You will get the frame, the price and the shipping date in writing.