What a Spin-On Filter Is
A spin-on filter is a complete disposable canister that threads onto a filter head. The media sits inside the sealed steel body, so there is no loose element to handle at service time. When the canister reaches its replacement point, the whole canister unscrews from the head and a new one threads on. The thread on this unit is 3/4-16 UNF, a common size on industrial lubricant pumps. The canister carries an anti-drainback valve and an internal bypass valve, both described below. This construction suits lubrication pump discharge filtration, gearbox oil circulation, hydraulic power unit return-line filtration, and compressor lubrication oil circuits. It fits oil only, not grease. For separate housings that take replaceable loose elements, see the cartridge set page.
Declared Specifications
| Type | spin-on cartridge canister |
| Rating | 10 micron absolute |
| Max pressure | 500 psi (34 bar) |
| Thread | 3/4-16 UNF |
| Bypass valve | 12 psi differential |
| Anti-drainback valve | yes |
| Media | cellulose/synthetic blend |
| Canister | steel, corrosion-resistant coated |
| Service | oil only, not grease |
Spin-On or Replaceable Cartridge?
These are two different service models, and the choice depends on how the machine is maintained. A spin-on unit is a complete canister: the media, the canister, and the valves form one sealed part, so the swap is fast and no loose element is handled or stored. A two-piece housing keeps a reusable body and takes a replacement element, which is covered on the cartridge set page. Market convention picks the spin-on where speed and simplicity dominate, and picks the two-piece housing where element economics dominate. Neither model is right for every circuit. Where access space is tight or the crew prefers fewer handling steps, the spin-on canister is usually the practical selection. Where the housing is large and opened on a planned schedule, a loose element may suit better.
Bypass and Anti-Drainback Valves
The bypass valve opens at 12 psi differential. That protects the circuit when the oil is cold or the media is loaded: instead of starving the line, oil continues to flow through the open bypass. The bypass setting is not the system pressure rating; the two are different numbers, and the canister maximum is 500 psi. Sustained bypass operation means the canister should be replaced, because the media is no longer passing full flow. The anti-drainback valve keeps oil in the head after shutdown. That retained oil lets the pump prime at restart rather than run dry for the first moments. Both valves work without any external signal or adjustment. A cold start on a machine in an unheated area is the case where the bypass earns its place. Confirm the filter head port and thread before ordering.
Installation and Replacement
Match the 3/4-16 UNF thread and the gasket to the filter head before ordering. Lightly oil the gasket, then hand-tighten the canister until the gasket contacts the head. Do not use a strap tool to over-torque the body. Leave service clearance below the canister so it can be unscrewed at replacement time. A typical replacement starting point is 1,000-2,000 operating hours or 3-6 months, shortened in high-contamination sites. Track the differential trend rather than relying on the calendar alone, because a rising differential shows loading before the hour count is reached. Check for weeping after the first run and correct the seating if any appears. Record the thread size and gasket diameter on the machine tag for the next order. Request a specification sheet through the quote page if the head dimensions are unknown.
What Is Supplied
One spin-on canister is supplied. Confirm the thread and gasket dimensions against your filter head when ordering. The full range sits on the lubrication filters category page. Related circuit parts include the Y-type strainer filter.
Frequently Asked Questions
What thread does it use?
It uses 3/4-16 UNF, a size common on industrial lubricant pumps.
Do I need to match the gasket?
Yes. Match the gasket diameter to the filter head and confirm it when ordering.
Can it filter grease?
No. It is for oil only and must not be used on grease lines.
What does the 12 psi bypass do?
It opens at 12 psi differential to keep oil flowing when cold or loaded. Sustained opening means replace the canister.
What is the anti-drainback valve for?
It keeps oil in the head after shutdown and prevents dry starts at restart.
What is the pressure rating?
The canister maximum is 500 psi, equal to 34 bar.
How often is replacement needed?
A typical starting point is 1,000-2,000 hours or 3-6 months, adjusted by contamination.
How is it different from a cartridge element?
This is a complete canister; a cartridge is a loose element in a reusable housing.
What signals replacement?
Sustained bypass events or a rising differential trend signal that the canister should be replaced.
Who builds and supports this filter?
IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006, builds and supports every unit. Email inquiry@isohitech.com for specifications and a quotation.
For machine-specific selection, reach us through the quote page.
