AW Gear Meters ZHM Series - Manual

AW Gear Meters 8809 Industrial Drive, Franksville, WI 53126  web: www.awgearmeters.com
 Tel: 262-884-9800  Fax: 262-884-9810  Email: [email protected]
REV. 03/09 ZHM.DOC
ZHM Series Flow Meter Maintenance Guide
Cleaning, inspecting or repairing a ZHM Series gear flow meter is easily accomplished
by following the procedures below.
- Remove the Pickup (12) from the flow meter body (6). (The
model HESK1 sensor is shown here) Some models have a dual
sensor, IGO6HD-XX, which has 2 built-in pickups, and is
attached by two sunken, hex-head screws.
- Note index marks (14). If symbols are absent, mark the body positions.
- Loosen the hex bolts (7) with a 5 mm key wrench - ZHM-04/8mm,
ZHM 05+06/10mm, ZHM 07/14mm. Remove the bolts except for two
opposing bolts (7)which should remain engaged by a few threads to
avoid damaging the shaft when the 2 flow meter housings separate.
- Holding the upper housing (6), gently tap the opposing bolts (7) to
separate the lower housing (1). Do not use chisels or screwdrivers
to split or pry apart the housings - this may damage the carbide
parts.
- After separation, remove and inspect the gears (4) & shafts (3).
Clean with solvent and a small brush. The gears should revolve
freely on the shafts.
- After cleaning all parts completely, the gears & shafts can be
reinserted. Check for free and easy rotation.
- Replace the O-ring (5) if deformed.
- Keep meter housings parallel during reassembly. Both locating
pins must be in place (2). Align index marks (14).
- Replace hex bolts as follows:
ZHM 01-03 - 15 Nm. *(This is hand tight).
ZHM 04 - 75 Nm.
ZHM 05/06 -130 Nm.
ZHM 07 -300 Nm.
- Over tightening will not cause damage but may restrict
operation if internal surfaces are not completely clean.
- After reassembly - a brief air blast will spin the gears.
This should be clearly audible given a moderate
background noise level.
- Clean any debris from the pickup port, insert Hall Sensor
all the way, and then back off 1/4 revolution and tighten
lock nut. * Do not over tighten *
- With the dual sensor, the electrical connector should
point in the flow direction after reassembly. The sensor should
fit flush on the meter body with good hex screw alignment.
- Optional PTFE space fillers (10) are available to fill
space behind the conversion fittings when multi-colored
materials are being metered.