// Catalogue

Pump to Motor Bell Housings

Bell housings bolt a hydraulic pump to an electric motor’s face, and the coupling inside joins the two shafts so they turn as one. TSA Hydraulics Engineering supplies both within the Motors family of our Motors & Drives range, plus inserts and damping rings.

The cheapest part on a power unit can wreck the most expensive one. A worn coupling insert, or a housing that sits slightly off centre, puts side load on the pump shaft, and the seal and bearings pay for it. Give us the motor frame size and the pump model, and we will match a housing and coupling that line up first time.

// Buying guide

How the Pieces Fit

Bell housing: a cast aluminium or steel adaptor, with the motor flange on one end and the pump flange on the other.
Coupling hubs: one on each shaft, bored and keyed or splined to suit.
Insert or spider: the flexible part between the hubs, which takes up small misalignment and soaks up shock.

Because the housing locates both flanges on spigots, it keeps the shafts in line without any manual alignment.

Choosing a Bell Housing

Start with two numbers, not one:

Motor side: the IEC frame size and flange, such as a B5 or B35 mounting, which sets the flange diameter and shaft.
Pump side: the pump flange, such as SAE A, SAE B or an ISO pattern, with 2 or 4 bolts.

The housing must also be long enough to fit both shafts and the coupling, with a small gap between the hubs.

Coupling Types

Jaw couplings: the most common choice, with a polyurethane spider between two hubs.
Pin and bush couplings: tough and simple, for larger motors.
Gear couplings: compact and strong, for high torque.
Disc couplings: stiff and free of backlash, often used with servo motors.

Spider inserts come in different hardness grades, often colour-coded, for different torque and damping needs.

Reducing Noise and Vibration

Damping rings between the housing and the motor cut noise passing into the power unit tank.
Anti vibration mounts and foot brackets support heavier pumps.
A good insert absorbs pressure pulses before they reach the motor bearings.

Signs of Wear

Rubber dust or crumbs under the housing.
A knocking sound when the motor starts or stops.
Leaking pump shaft seals or noisy bearings.
Rising vibration on your monitoring trend.

Change the insert at the first sign. It costs far less than a pump.

Bell Housings Specifications to Check

Motor IEC frame size, flange and shaft
Pump flange, spigot and shaft details
Housing length and material
Coupling type, hub bores and keyways
Insert hardness and torque rating
Any need for a damping ring or foot bracket

Why Buy From TSA Hydraulics Engineering

As a bell housings supplier, we work from both the motor and the pump details, so the housing, hubs and insert fit as one set. You get OEM or equivalent options, and help sourcing bell housings replacement parts such as spider inserts, hubs and damping rings. We tell you upfront whether a part is genuine or an equivalent.

// FAQs