We can customize our vent caps for special applications. Below are examples of a few of the customizations we have done.

SCREEN MESH
The screen meshes we use are 24 mesh or finer to exclude insects such as mosquitoes.  The mesh is plastic so it it non-corroding, however there are different choice of material available.   Conventionally we use polypropylene for its physical rigidity but Nylon and Polyester are also viable alternatives. Here is a chemical resistance chart comparing the three materials side-by-side.

Pipe Screen in-line
IN-LINE PIPE SCREEN

PIPE SCREEN (IN-LINE)

This customer wanted a screen in their pipe line without our usual mushroom cap. The mesh is the same as our standard caps which is polypropylene 24 x 24 mesh. (or 800 microns)  This example is on a 4 inch male thread but we have made the same pipe screen in many sizes.

Vent cap with outlet
VENT CAP WITH OUTLET

VENT CAP WITH SIDE OUTLET

This is a custom product made to our customer’s specifications. They wanted a side outlet for liquid transfer.

flange mount vent cap
UNDER 2 INCH

VENT CAP WITH FLANGE 

Vent caps 2 inches and smaller can be screwed into a threaded flange. We tap the flange so the vent cap threads all the way in. There is no reason to use an one-piece construction. (see image to the LEFT)

Vent caps 3 inches and larger sometimes may prefer a one-piece integral construction. (RIGHT)

Mushroom cap with plastic screen and flange
4 INCH FLANGE VENT CAP
Large Tank Vent Cap - Plastic
COMPARISION OF SCREENS

VENT CAP WITH FINE SCREEN.  Due to a local ordinance this customer wanted an 8 inch vent cap with 31 mesh screen (approximately 600 microns) instead of the perforated PVC sheet. 

14979

Colored vent cap (black)
ABS PARTS
TREATED PVC

 COLORED VENT CAP. 

This customer wanted black color so we treated the parts so they are colored black. We experimented with various coatings, including a ceramic coating by the trade name Ceracoat. Our customer selected the treatment that passed their challenging “stone chipping” tests.

Another option we considered was to use ABS pipe parts which are manufactured in black plastic. These would be intrinsically resistant to the “stone chipping” test, but these are much more costly and prone to chalking in sunlight, and didn’t have the glossy appearance that the treated caps were able to acheive.

Finally, it is possible to have the cap molded in black, but our customer’s volume didn’t justify a run of custom color with our injection molding.

Vent cap with stainless screen
STAINLESS SCREEN

STAINLESS SCREEN.

This customer wanted wanted to comply with specification drawings that called out stainless screen.  Although we see no advantage of stainless screens in preference to polypropylene, substituting a stainless screen saved a lot of engineering time to re-evaluate and re-issue the specification drawings. 

We used 24 x 24 mesh 316 stainless steel so it is still meets our corrosion-proof standard.

 

[32390]

10 inch vent cap with pipe stub mount
10" VENT CAP

SPECIAL PIPE SIZE

This customer had an odd-size pipe stub existing, and wanted to use it to mount a vent cap.  To accomplish this we machined a correctly-sized plastic piece inside the (gray) pipe part of the vent cap so the vent cap fit the customer’s pipe exactly.

flange vent cap

LOW PROFILE VENT CAP WITH FLANGE MOUNT.

Screen is perforated PVC with 1/8″ holes – 40% open area. This unit is a low profile with oeverall height only 6 inches.  The vent cap is mounted on a 10 inch flange.

tall custom vent cap

TALL VENT CAP

Made to our customer’s specifications. The intent was to allow sloshing in vehicles without spillage out of the vent cap.

mushroom style vent cap slip



 

VENT CAP with a built-in check valve to control air flow in one direction.