ZEM Series Injectors
ZEM is a series designation inside the Bijur Delimon SureFire positive displacement injector family, not a standalone brand or maker. These aftermarket injectors cross-reference the SureFire PDI line, and you can review what a central lubrication system is before ordering.
Series, Threads, and Construction
- ZEM 32: M8x1 inlet thread, screw-in injector that mounts in a manifold bar.
- ZEM 33: M10x1 inlet thread, screw-in injector that mounts in a manifold bar.
- ZEM 34: M10x1 inlet thread, built-in cast manifold body.
- ZEM 35: M10x1 inlet thread, built-in cast manifold body.
- ZEM 39: M12x1 inlet thread, built-in cast manifold body.
The screw-in series 32 and 33 require a separate manifold bar with threaded ports, while series 34, 35, and 39 include their own manifold body, which simplifies installation where space allows a cast assembly.
Output Options by Series
- ZEM 32, 33, 34: 0.01, 0.03, 0.06, 0.10, 0.16 cc
- ZEM 35: 0.06, 0.10, 0.20, 0.30, 0.40, 0.60 cc
- ZEM 39: 0.20, 0.30, 0.40, 0.60, 1.00, 1.50 cc
The smallest dose across the ZEM range is 0.01 cc on series 32 to 34, while the largest single shot is 1.50 cc on series 39.
Operating Window
These injectors handle oil viscosity from 20 to 1500 cSt. The minimum operating pressure is 15 bar and the maximum is 45 bar. Each injector relieves at 0.7 bar when the line vents between cycles. Oil is the standard medium, and soft grease up to NLGI 000 is possible after confirming the application with Bijur Delimon.
How a PDI Injector Works
A pump charges one common supply line, and each injector meters its own fixed dose per cycle as pressure rises. When the system vents, the line pressure drops and each injector resets for the next shot. See single line lubrication system operation for a deeper explanation of the charging and venting sequence.
Choosing Injectors and a Pump
Determine the dose each bearing needs per cycle from bearing size and machine cycle time, then pick an injector output that matches. Keep all injectors on one manifold within the same series so thread pattern and manifold body style stay uniform. For a matching oil pump, review the 2L Bijur lubrication oil pump and contact the quotation team if you need help pairing components.
Frequently Asked Questions
What is a positive displacement injector?
A positive displacement injector meters one fixed volume of oil per pressure cycle. It discharges that volume only when the supply line reaches firing pressure.
Can one injector have multiple output options?
No, each injector delivers only the fixed dose stamped or listed for its series and size. You must order a different injector part for a different output per cycle.
How do I select the right output per cycle?
Calculate the bearing lubricant requirement from bearing width, shaft diameter, and machine cycle time. Then choose the injector series output closest to that calculated dose.
Do these injectors work with grease?
Yes, oil is standard, and soft grease up to NLGI 000 is possible. Always contact Bijur Delimon before running soft grease through any ZEM injector.
What happens when the system vents?
Each injector relieves at 0.7 bar as line pressure falls after the pump stops. That relief action is normal and resets the injector piston for the next cycle.
Can I mix different ZEM series on one manifold?
No, keep series consistent on one manifold because thread sizes and manifold body styles differ between series. Mixing series can create installation and sealing problems.
What inlet threads do I need?
ZEM 32 uses M8x1, series 33, 34, and 35 use M10x1, and ZEM 39 uses M12x1. Match the manifold port thread to the injector series you choose.
What pressure range should the pump provide?
The system must develop at least 15 bar and never exceed 45 bar at the injectors. A pump outside that range will not fire injectors correctly.
How does viscosity affect injector operation?
These injectors work with oil viscosity from 20 to 1500 cSt. Very thick oil near the upper limit may slow piston reset, so verify pump pressure and vent timing.
Who builds and supports these units?
IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006, builds and supports every unit. Email inquiry@isohitech.com for specifications and a quotation.
For ordering assistance, contact the quotation team. Bijur Delimon is a trademark of its respective owner. This page covers aftermarket injectors, not manufactured, sponsored, or endorsed by Bijur Delimon. ZEM and the series numbers are Bijur Delimon designations shown for cross-reference identification only.
