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Replacing Kraissl Transfer Valves
If you're running Kraissl transfer valves, HYCOA and HICORP offer direct drop-in replacements that eliminate the leakage, lubrication, and packing maintenance issues inherent to the plug-type design — with no re-piping required.
Download Comparison PDFWhy Engineers Upgrade from Kraissl
Kraissl plug-type transfer valves have been in service for decades — which means there are a lot of them still running in the field. But the tapered metal-to-metal plug design has fundamental limitations: leakage that worsens as packing wears, lubrication requirements, and operating torque that can require a lifting jack in larger sizes.
HYCOA's JR-33 and HICORP transfer valves are engineered as direct drop-in replacements. They match existing Kraissl flange bolt patterns and face-to-face dimensions — so you get a significant performance upgrade with no re-piping and minimal downtime.
The result: zero internal leakage, no lubrication, no packing adjustments, and API 598 & API 614 compliance — in the same footprint as your existing Kraissl installation.
Bottom Line
For critical fluid systems — turbine lube oil, API 614 skids, power generation — HYCOA's patented Shoe Seal design delivers performance that traditional plug-type valves simply cannot match.
HYCOA Advantages
Kraissl Limitations
Comparison Guide — PDF
Download the full HYCOA vs. Kraissl comparison document for your engineering files or to share with your team.
Download PDFWhy HYCOA Outperforms Kraissl
Six engineering advantages that make the HYCOA JR-33 the preferred choice for critical fluid systems.
Zero Internal Leakage
Patented Shoe Seal mechanically locks into position — engineered to eliminate internal bypass regardless of cycles or wear.
Zero Frictional Drag
The shoe seal lifts completely during transfer — no drag, no pressure spike, no flow interruption.
No Lubrication Required
Eliminates grease fittings and packing adjustments — reduces maintenance cost and contamination risk.
Low Operating Torque
Smooth, consistent switching even in large sizes — no lifting jack or handle extensions needed.
Positive Mechanical Lockdown
No springs — mechanically locked in both active and standby positions for stable, reliable sealing.
API 598 & API 614 Rated
Designed and tested per API standards for special-purpose rotating equipment lubrication systems.
What You're Replacing — and What You're Upgrading To
Understanding the Kraissl plug design makes it clear why engineers switch to HYCOA.
What you're replacing
Kraissl Transfer Valves
Tapered plug diverter — metal-to-metal sealing with known limitations
Kraissl valves use a tapered metal-to-metal valve plug rotated under load. Sealing depends on packing condition and metal fit — both of which degrade over time, increasing internal bypass and maintenance demands.
- Tapered metal-to-metal valve plug rotated under load — friction and wear over time
- Locking flange and external packing require periodic field adjustment
- Sealing performance degrades as packing wears — internal bypass increases
- Lubrication required at grease fittings — ongoing maintenance cost
- Moderate to high operating torque — may require a lifting jack in larger sizes
- No API 598 or API 614 rating for critical fluid system applications
What you're upgrading to
HYCOA Transfer Valves
Patented Shoe Seal Lockdown — engineered zero leakage, drop-in replacement
HYCOA (e.g., JR-33 series) uses a patented Shoe Seal Lockdown design that's very different from a simple tapered plug. Instead of relying on metal-to-metal contact alone, HYCOA's design uses resilient shoe seals that mechanically lock into place and provide zero internal leakage when switching paths.
- Zero Internal Leakage
- Zero Frictional Drag
- No Lubrication Required
- Low Operating Torque
- Positive Mechanical Lockdown
- API 598 & API 614 Rated
Kraissl Transfer Valve Specifications
Model 72AAF(H)S(S) Series — Cast Carbon or Stainless Steel, Flanged Ports. U.S. Patent No. 3,567,181.
Features
- Adjustable locking flange establishes valve clearance
- Independent gland adjustment for external packing access
- Tapered, all-metal valve plug for durability & renewability
- Continuous flow without changeover interruption
- Drain connection on valve chamber
- Units individually tested
- Handle indicates side in use
- Optional gage taps
- Optional lifting jack
- Optional valve plug coatings
Purpose
Kraissl Transfer Valves are used to "parallel" or duplex two pieces of pipeline equipment in continuous flow without shut off of either one. Examples include duplexing of two heat exchangers, filters or tanks.
These rugged units are time tested for many years in a wide variety of fluid applications.
Application
Available in ¾″ through 8″ sizes in ANSI flange classes 150, 300, 400, 600, 900, 1500 and higher. Special ring joint flanges can also be furnished.
Provides a simple, cost-effective way to duplex flow equipment where continuous flow must be maintained with no flow interruption for down-side servicing.
Design Specifications
Straight-through alignment of single inlet and outlet ports. Other models with same-side inlet and outlet ports also available.
Internal channels are 100% full-flow — same cross-sectional area as the equivalent pipe size.
Furnished in standard and high-pressure models. NPT and weld-end models also available.
Materials include cast carbon or stainless steel bodies and covers. Valve plugs in stainless steel, bronze, or cast iron.
Drain plugs provided in the valve chamber. Adjustable locking flange holds the valve plug on its seat.
Optional lifting jack standard on 6″ and 8″ sizes and all units with a stainless steel valve plug.
Separate external gland allows easy access to stem packing without complete disassembly, even while in service.
Each valve is tested and serial numbered for accountability and traceability. Test results provided with each valve.
Sizes, Ratings & Dimensions
All dimensions in inches and subject to casting and production variations.
ANSI Class 150 Flanges
275 PSIG Maximum Working Pressure| Model | Size | Flg. Dia. | B.C. Dia. | # Bolts | Bolt Hole | R.F. Dia. | Min. Flg. Thick. | Wgt. (lb) | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 72-33AAFS | 1" | 4 1/4 | 3 1/8 | 4 | 5/8 | 2 | 3/8 | 50 | 12 7/8 | 6 1/4 | 8 1/2 | 5 1/4 | 9 1/4 | 1 | 5 1/8 |
| 72-37AAFS | 1 1/2" | 5 | 3 7/8 | 4 | 5/8 | 2 7/8 | 1/2 | 55 | 14 1/2 | 7 7/8 | 9 3/8 | 4 15/16 | 10 | 1 | 6 3/8 |
| 72-39AAFS | 2" | 6 | 4 3/4 | 4 | 3/4 | 3 5/8 | 9/16 | 90 | 16 3/8 | 9 5/16 | 12 | 6 1/4 | 12 | 7/16 | 6 3/4 |
| 72-41AAFS | 2 1/2" | 7 | 5 1/2 | 4 | 3/4 | 4 1/8 | 5/8 | 120 | 17 7/8 | 10 13/16 | 12 5/8 | 6 1/2 | 13 | 7/16 | 7 3/4 |
| 72-43AAFS | 3" | 7 1/2 | 6 | 4 | 3/4 | 5 | 11/16 | 141 | 18 7/16 | 11 3/8 | 12 1/2 | 6 7/8 | 14 | 1/8 | 7 3/4 |
| 72-47AAFS | 4" | 9 | 7 1/2 | 8 | 3/4 | 6 3/16 | 7/8 | 250 | 19 3/4 | 12 1/16 | 15 5/8 | 9 | 21 | 2 11/16 | 10 1/4 |
| 72-51AAFS | 6" | 11 | 9 1/2 | 8 | 7/8 | 8 1/2 | 15/16 | 510 | 29 3/8 | 12 1/2 | 24 | 12 | 26 | 4 3/4 | 11 1/2 |
| 72-53AAFS | 8" | 13 1/2 | 11 3/4 | 8 | 7/8 | 10 5/8 | 1 1/16 | 1300 | 36 7/8 | 15 1/8 | 32 1/2 | 15 1/2 | 30 1/2 | 7 3/8 | 14 |
ANSI Class 300 Flanges
720 PSIG Maximum Working Pressure| Model | Size | Flg. Dia. | B.C. Dia. | # Bolts | Bolt Hole | R.F. Dia. | Min. Flg. Thick. | Wgt. (lb) | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 72-33AAFHS-300 | 1" | 4 7/8 | 3 1/2 | 4 | 3/4 | 2 | 5/8 | 70 | 13 3/16 | 6 9/16 | 8 1/2 | 5 1/4 | 9 1/4 | 1 | 5 1/8 |
| 72-37AAFHS-300 | 1 1/2" | 6 1/8 | 4 1/2 | 4 | 7/8 | 2 7/8 | 3/4 | 75 | 15 1/16 | 8 7/16 | 9 3/8 | 4 15/16 | 10 | 1 | 6 3/8 |
| 72-39AAFHS-300 | 2" | 6 1/2 | 5 | 8 | 3/4 | 3 5/8 | 13/16 | 110 | 16 5/8 | 9 9/16 | 12 | 6 1/4 | 12 | 7/16 | 6 3/4 |
| 72-41AAFHS-300 | 2 1/2" | 7 1/2 | 5 7/8 | 8 | 7/8 | 4 1/8 | 15/16 | 145 | 18 1/8 | 11 1/16 | 12 5/8 | 6 1/2 | 13 | 7/16 | 7 3/4 |
| 72-43AAFHS-300 | 3" | 8 1/4 | 6 5/8 | 8 | 7/8 | 5 | 1 1/16 | 170 | 19 3/16 | 12 1/8 | 12 1/2 | 6 7/8 | 15 | 1/2 | 8 1/2 |
| 72-47AAFHS-300 | 4" | 10 | 7 7/8 | 8 | 7/8 | 6 3/16 | 1 3/16 | 295 | 20 1/4 | 12 9/16 | 15 5/8 | 9 | 21 | 2 11/16 | 10 1/4 |
| 72-51AAFHS-300 | 6" | 12 1/2 | 9 1/2 | 12 | 7/8 | 8 1/2 | 1 3/8 | 705 | 30 | 14 | 24 | 12 | 26 | 5 | 12 3/4 |
ANSI Class 600 Flanges
1440 PSIG Maximum Working Pressure| Model | Size | Flg. Dia. | B.C. Dia. | # Bolts | Bolt Hole | R.F. Dia. | Min. Flg. Thick. | Wgt. (lb) | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 72-33AAFHS-600 | 1" | 4 7/8 | 3 1/2 | 4 | 3/4 | 2 | 11/16 | 75 | 15 1/8 | 8 1/2 | 10 3/8 | 5 5/8 | 11 | 5/16 | 6 3/8 |
| 72-37AAFHS-600 | 1 1/2" | 6 1/8 | 4 1/2 | 4 | 7/8 | 2 7/8 | 7/8 | 80 | 15 3/4 | 9 1/8 | 10 3/8 | 5 5/8 | 11 | 5/16 | 6 3/8 |
| 72-39AAFHS-600 | 2" | 6 1/2 | 5 | 8 | 3/4 | 3 5/8 | 1 | 200 | 18 1/4 | 11 7/16 | 16 3/8 | 8 5/8 | 17 1/4 | 9/16 | 8 3/4 |
| 72-43AAFHS-600 | 3" | 8 1/4 | 6 5/8 | 8 | 7/8 | 5 | 1 1/4 | 292 | 20 | 12 3/4 | 15 3/4 | 8 1/4 | 16 1/2 | 0 | 8 1/2 |
ANSI Class 1500 Flanges
3600 PSIG Maximum Working Pressure| Model | Size | Flg. Dia. | B.C. Dia. | # Bolts | Bolt Hole | R.F. Dia. | Min. Flg. Thick. | Wgt. (lb) | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 72-37AAFHS-1500 | 1 1/2" | 7 | 4 7/8 | 4 | 1 1/8 | 2 7/8 | 1 1/4 | 117 | 16 3/16 | 9 9/16 | 11 1/8 | 6 | 11 3/4 | 5/16 | 6 3/8 |
| 72-39AAFHS-1500 | 2" | 8 1/2 | 6 1/2 | 8 | 1 | 3 5/8 | 1 1/2 | 290 | 19 1/4 | 12 7/16 | 16 3/8 | 8 5/8 | 17 1/4 | 9/16 | 8 3/4 |
| 72-43AAFHS-1500 | 3" | 10 1/2 | 8 | 8 | 1 1/8 | 5 | 1 7/8 | — | 23 1/2 | 16 | 17 3/8 | 9 1/8 | 18 | 0 | 10 3/4 |
ANSI Class 2500 Ring Joint Flanges
6000 PSIG Maximum Working Pressure| Model | Size | Flg. Dia. | B.C. Dia. | # Bolts | Bolt Hole | R.F. Dia. | Min. Flg. Thick. | Wgt. (lb) | A | B | C | D | E | F | G |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 72-37AAFHS-2500 | 1 1/2" | 8 | 5 3/4 | 4 | 1 1/4 | 4 1/2 | 1 3/4 | 350 | 21 5/8 | 8 3/4 | 15 1/2 | 7 3/4 | 17 | 3 1/2 | 8 1/4 |
| 72-39AAFHS-2500 | 2" | 9 1/4 | 6 3/4 | 8 | 1 1/8 | 5 1/4 | 2 | — | 22 1/4 | 9 3/4 | 19 5/8 | 9 5/8 | 23 | 4 3/8 | 9 1/2 |
* Plus 1/16″ R.F. on Class 150 & 300 flanges and 1/4″ R.F. on higher pressure ratings. 5/16″ R.F. on Class 2500 R.J., 1½″ and 2″ sizes.
** Add 1½″ to the "A" dimension if unit is furnished with lifting jack through 4″ size. On 6″ & 8″, lifting jack is included and handle length is 14″.
*** Material Group 2.1 & 2.2 @ 100°F (ANSI B16.5). Class 900 & 1500 flange dimensions are the same through 2½″ sizes.
Threaded NPT / Socket Weld Transfer Valves
Cast Iron, Carbon Steel or Stainless Steel — Threaded NPT or Socket Weld Ports. Pressure Range: 200 to 275 PSIG & Higher. U.S. Patent No. 3,567,181.
Features
- Adjustable locking flange establishes valve clearance
- Independent gland adjustment for external packing access
- Tapered, all-metal valve plug for durability & renewability
- Continuous flow without changeover interruption
- Drain connection on valve chamber
- Units individually tested
- Handle indicates side in use
- Optional gage taps
- Optional lifting jack
- Optional valve plug coatings
Purpose
Used to "parallel" or duplex two pieces of pipeline equipment in continuous flow without shut off of either one — including heat exchangers, filters, and tanks.
Time tested for many years in a wide variety of fluid applications, including lubrication oil systems built in accordance with the A.P.I. 614 specification.
Application
Available in 1½″ through 3″ sizes in various pressure ratings. Same-side orientation of single inlet and outlet ports; straight-through opposite-side models also available.
Provides a simple, cost-effective way to duplex flow equipment with no flow interruption for down-side servicing.
Design Specifications
Same-side orientation of single inlet and outlet ports. Straight-through opposite-side models also available.
Internal channels are 100% full-flow — same cross-sectional area as the equivalent pipe size.
Bodies and covers in cast iron, carbon steel, or stainless steel. Valve plugs in cast iron, bronze, stainless steel, or special materials.
Optional Shure-tite™ rubberized valve plug available for positive shut-off seal with easy operation.
Separate external gland allows easy access to stem packing without complete disassembly, even while in service.
Each valve is tested and serial numbered for accountability and traceability. Test results provided with each valve.
Maximum Working Pressure
| Material | Max Working Pressure |
|---|---|
| Cast Iron | 200 PSIG |
| Cast Steel | 275 PSIG |
Port Flange Compatibility
| Valve Material | Flange Standard |
|---|---|
| Cast Iron | ANSI B16.1 Class 125 |
| Carbon Steel | ANSI B16.5 Class 150 |
Dimensions — Inches
| Model No. | Pipe Size | A | B*** | C*** | D** | E |
|---|---|---|---|---|---|---|
| 72-37ABF(S) | 1-1/2" | 6 3/8 | 4 7/16 | 10 | 14 1/2 | 2 1/2 |
| 72-39ABF(S) | 2" | 6 3/4 | 5 3/4 | 12 | 17 | 3 |
| 72-43ABF(S) | 3" | 7 3/4 | 6 5/8 | 14 | 18 3/4 | 3 3/4 |
| 72-47ABF(S) | 4" | 10 1/4 | 6 5/8 | 21 | 21 5/8 | 4 1/2 |
Model / Material Suffixes
| Suffix | Description |
|---|---|
| S | Cast Steel — ASTM A216 WCB |
| SS304 | Cast 304 Stainless Steel — ASTM A351-CF8 |
| SS316 | Cast 316 Stainless Steel — ASTM A351-CF8M housing & cover |
Port Interconnections
| Valve Position | Port Interconnection |
|---|---|
| Position Shown | 1 & 2, 3 & 4 |
| Other Position | 1 & 2′, 3′ & 4 |
Handle Orientation
Standard handle swings over Ports 1–4 (inlet side). Optional reverse handle swings over the opposite side. Handle guard indicates the side currently in use.
** Add 1½″ if furnished with optional lifting jack. See drawing B3522.
*** Tolerance: +1/8″, −0″
Dimensions are in inches and subject to casting & assembly variations.
Key Design Differences
Sealing Mechanism
Kraissl
- Uses tapered plug and seat (metal-to-metal) sealing
- Seal performance depends on metal contact and valve machining
- External packing required — periodic adjustment needed
- Leakage increases as packing wears over time
HYCOA
- Uses patented Shoe Seal (resilient seals) for positive containment
- Designed to eliminate internal bypass leakage and resist wear
- Mechanically locked — not dependent on spring force — for stable sealing
- No packing — no adjustment, no degradation over time
Takeaway: HYCOA seals deliver true zero leakage and lower friction than traditional plug-style designs.
Ease of Operation
Kraissl
- Manual plug rotates under load — friction against seat
- May require optional lifting jack for larger sizes
- Packing adjustments are external but still require maintenance
- Lubrication required at grease fittings
HYCOA
- Shoe seal lifts completely during transfer — zero frictional drag
- Lower operating torque — no lifting jack needed
- Designed for smooth, consistent switching even after many cycles
- No lubrication required — maintenance-free sealing
Construction & Application Focus
Kraissl
- Cast bodies (iron, steel, stainless) with removable plug
- Good for general industrial use — duplexing filters, heat exchangers, tanks
- Traditional, proven design in many installations
HYCOA
- Heavy-duty fabricated construction with precision sealing
- Often chosen for critical fluid systems like turbine lube oil
- Lower pressure drop, longevity, and high reliability emphasized
Signs It's Time to Upgrade
Common Kraissl pain points
- Increasing internal bypass or cross-contamination between circuits
- Frequent packing adjustments or grease fitting maintenance
- High operating torque requiring a lifting jack to switch
- System requires API 614 compliance for turbine lube oil service
The HYCOA / HICORP upgrade path
- Direct drop-in replacement — matches Kraissl bolt patterns & face-to-face dimensions
- Zero internal leakage from day one, maintained over the valve's life
- No lubrication, no packing — maintenance-free sealing
- API 598 & API 614 rated for critical fluid systems
Full Comparison Table
12-point side-by-side comparison of HYCOA JR-33 vs. Kraissl transfer valves
| Feature | Kraissl | HYCOA JR-33 |
|---|---|---|
| Valve Type | Tapered plug diverter | Shoe Seal transfer valve |
| Sealing Method | Metal-to-metal plug + packing | Patented resilient Shoe Seal |
| Internal Leakage | Depends on fit & packing condition | Engineered zero leakage |
| Frictional Drag During Transfer | Plug rotates under load — friction & wear | Shoe lifts completely — zero drag |
| Lubrication Required | Yes — grease fittings required | No — maintenance-free sealing |
| Operating Torque | Moderate to high (may need lifting jack) | Low — smooth consistent switching |
| Packing Adjustments | External packing, periodic adjustment | None required |
| Mechanical Lockdown | Locking flange on plug | Positive mechanical lockdown — no springs |
| API Standards | General industrial | API 598 & API 614 rated |
| Drop-In Replacement | — | Yes — matches Kraissl bolt patterns & face-to-face |
| Body Construction | Cast iron, steel, or stainless | Heavy-duty fabricated construction — engineered for critical service |
| Best Application | General industrial duplexing — not rated for API 614 | Critical fluid systems — turbine lube oil, API 614 |
Find Your HYCOA Replacement Model
Use our searchable cross-reference table to find the exact HYCOA JR-33 model that replaces your Kraissl valve.
HYCOA Transfer Valve Products
Frequently Asked Questions
Ready to Upgrade from Kraissl?
Our team can help you identify the right HYCOA replacement for your existing Kraissl installation — including dimensional cross-references and retrofit guidance.
HYCOA® JR-33
Select a Valve
- JR3
3-Way Transfer Valve
Single flow path switching
- TP
3-Way Twin-Pak
Inlet + outlet in one body
- 6SS
6-Way Same-Side
Most popular duplex config
- 6IL
6-Way Inline
Straight-through piping
- 6OS
6-Way Opposite Side
Opposing supply & return lines
- HIC
HICORP Transfer Valves
2″ – 12″ large-bore service
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