When maintaining ANSI B73.1 process pumps, plant engineers and procurement teams frequently face a critical question: Can Durco Mark III parts be used in Goulds 3196 pumps, and vice versa? The answer is nuanced — some components interchange directly, while others require understanding of the fundamental design differences between these two industry-standard pump platforms.
This guide provides a comprehensive, part-by-part interchangeability analysis based on 15+ years of reverse-engineering both pump families. As an independent aftermarket manufacturer producing replacement parts for both Goulds 3196 (G196 Series) and Durco Mark III (D Mark III Series), we have deep insight into where the two designs converge and where they diverge.
The Foundation: ASME B73.1 Dimensional Standard
Both Goulds 3196 and Durco Mark III pumps are manufactured to ANSI/ASME B73.1 — the governing standard for horizontal end-suction centrifugal pumps in chemical process service. This means:
- Mounting footprint is identical — baseplate bolt patterns match, so a Durco Mark III pump can be dropped directly onto a Goulds 3196 base without modification.
- Nozzle locations are standardized — suction and discharge flange positions and dimensions are consistent across both brands within the same frame size.
- Shaft centerline height — the critical dimension for coupling alignment — is the same for equivalent frame sizes (STX/Group I, MTX-LTX/Group II, XLTX/Group III).
- Overall pump dimensions (CP, D, X, E, F, Y, H, U values) match within tolerance, enabling direct whole-pump swap-outs.
Bottom line: You can replace an entire Goulds 3196 with a Durco Mark III equivalent (or our G196/D Mark III aftermarket pumps) without touching piping, baseplates, or motor mounts.
Key Design Difference: Open Impeller vs. Reverse Vane Impeller
Before diving into part-level interchangeability, it’s essential to understand the single biggest technical difference between these two pump families:
| Feature | Goulds 3196 (G196 Series) | Durco Mark III (D Mark III) |
|---|---|---|
| Impeller Type | Open impeller | Reverse vane (semi-open) impeller |
| Front Clearance Adjustment | External adjustment against front casing | External adjustment against rear cover plate |
| Seal Chamber Pressure | Standard — front wear ring controls leakage | Reduced — rear pump-out vanes lower seal chamber pressure |
| Thrust Load | Higher axial thrust (open face) | Lower axial thrust (balanced by rear vanes) |
| Mechanical Seal Life | Standard | Extended — lower seal chamber pressure reduces seal face loading |
| Wear Ring Location | Front casing wear ring | No front wear ring — rear cover plate serves as wear surface |
This means: You cannot simply thread a Durco impeller onto a Goulds shaft, or vice versa. The entire wet-end assembly (impeller, cover, casing) is designed as an interdependent system. However, individual power-end components are far more interchangeable.
Part-by-Part Interchangeability Matrix
The following table shows interchangeability at the component level. Use this as a quick reference when sourcing replacement parts for either pump platform.
| Component | Goulds 3196 POS | Durco Mark III POS | Direct Interchange? | Notes |
|---|---|---|---|---|
| Casing (Volute) | 100 | 100 | ⚠️ Wet-end only | Same nozzle dimensions per ANSI B73.1, but internal volute profile differs. Replace as a complete wet-end assembly. |
| Impeller | 101 | 104 | ❌ Not directly | Open vs. reverse vane design. Shaft taper/fit may differ. Replace impeller + cover + casing as a set for cross-brand swaps. |
| Shaft | 122 | 107 | ⚠️ Check fit | Same SAE 4140 or 316SS material. Shaft diameters at bearing seats typically match within same frame group, but impeller-end taper, keyway, and sleeve fit must be verified. |
| Shaft Sleeve | 126 | 201B (Hook Sleeve) | ⚠️ Check dimensions | Both use 316SS. Length and OD match within same group, but hook sleeve design on Durco requires matching gland. |
| Stuffing Box Cover / Seal Chamber | 184 / 184M | 108 (Rear Cover) | ❌ Different design | Goulds uses front cover with wear ring; Durco uses rear cover plate. Not interchangeable. |
| Bearing Housing | 228 | 129 | ⚠️ Frame-level | Bolt pattern and shaft centerline match within same frame group. Verify bearing bore diameters. |
| Bearing Frame / Frame Adapter | 108 | 109A | ⚠️ Assembly-level | Mounting bolt pattern often matches. Replace with bearings as a complete assembly. |
| Thrust Bearing | 112 | 130 / 131 | ✅ Often same | Both use SKF or equivalent angular contact / deep groove bearings. Standard bearing numbers cross-reference directly. |
| Gland (Packing) | 250 | 112 | ⚠️ Check fit | Gland bolt PCD may vary. Verify stud spacing before ordering. |
| Gasket — Casing | 351 | 105 | ❌ Different | Casing gasket profiles are unique to each brand’s volute design. |
| Oil Seals (Inboard/Outboard) | 332A / 333A | 125 / 136 | ✅ Same function | Labyrinth oil seals (INPRO VBXX or equal) — cross-reference by shaft diameter and housing bore. |
| Oil Sight Glass | 319 | 153 / 245 | ✅ Standard part | Generic component. Interchangeable if thread size matches. |
Frame Group Correspondence: Which Pump Sizes Match?
Use this cross-reference table to find the equivalent pump size across both brands. Pumps in the same row share identical mounting dimensions (baseplate, nozzle locations, shaft centerline).
| Goulds 3196 Frame | Durco Mark III Group | Common Pump Sizes | Max Impeller | Shaft Centerline |
|---|---|---|---|---|
| STX | Group I (1K) | 1×1.5-6, 1.5×3-6, 2×3-6, 1×1.5-8, 1.5×3-8, 2×3-8, 3×4-8 | 6″–8″ | 17.5″ (445 mm) |
| MTX / LTX | Group II (2K) | 1×2-10, 1.5×3-10, 2×3-10, 3×4-10, 4×6-10, 1.5×3-13, 2×3-13, 3×4-13, 4×6-13, 6×8-13, 8×10-13 | 10″–13″ | 23.5″ (597 mm) |
| XLTX | Group III (3K) | 6×8-15, 8×10-15, 3×6-14, 3×6-16, 4×6-16, 6×8-16, 8×10-16, 10×12-16, 8×10-17 | 15″–17″ | 33.875″ (860 mm) |
Practical Guidelines for Cross-Brand Parts Sourcing
✅ What You CAN Safely Do
- Complete pump replacement: Our G196 and D Mark III pumps are 100% dimensionally interchangeable with both Goulds 3196 and Durco Mark III respectively — same footprint, no piping changes.
- Complete wet-end assembly: Swap a full wet-end (casing + impeller + cover) between brands if within the same frame group. Dimensions match at the adapter interface.
- Power-end components: Bearings, oil seals, bearing housings, shafts, and sleeves within the same frame group can often interchange after dimensional verification.
- Gaskets & O-rings by dimension: Generic gaskets and O-rings in standard materials (Aramid, PTFE, FKM, NBR) interchange freely when dimensions match.
❌ What You Should NOT Do
- Never mix impeller types across brands — a Goulds open impeller won’t function correctly in a Durco reverse-vane casing, and vice versa.
- Never mix casing covers across brands — the cover-to-casing interface geometry is brand-specific.
- Never assume shaft interchangeability without verification — impeller-end tapers, keyway dimensions, and sleeve-land diameters differ between the two platforms.
How We Ensure True Interchangeability
At ANSI Pumps Pro (JINAN YINGSIMAN MACHINERY CO., LTD.), every replacement part we manufacture is validated against OEM dimensional databases accumulated over 15+ years. Our process includes:
- Reverse engineering from OEM samples — we maintain complete drawing libraries for both Goulds 3196 and Durco Mark III across all frame sizes.
- CMM (Coordinate Measuring Machine) inspection — every critical dimension verified to OEM tolerances before the part leaves our facility.
- Dynamic balance testing — all impellers balanced to ISO 1940 G6.3 or better.
- 100% fit-testing — components are trial-assembled on reference fixtures to guarantee field interchangeability.
- Full MTR (Material Test Report) EN 10204 3.1 — traceable chemical and mechanical properties for every heat of material.
Need help identifying the correct replacement part? Contact our engineering team with your pump model, serial number, or OEM part number — we’ll provide a cross-reference within 24 hours.
Quick Cross-Reference: OEM Part Numbers
Common OEM casing part numbers by pump size, with our equivalent replacement reference numbers:
| Pump Size | Goulds 3196 OEM Casing # | Durco Mark III OEM Casing # | Our Equivalent Ref. |
|---|---|---|---|
| 1×1.5-6 (STX / Group I) | GAB100 / 104554 | DKA100 / DY50794A | Available — inquire |
| 1.5×3-6 (STX / Group I) | GAC100 / 104556 | DKC100 / DY50733A | Available — inquire |
| 2×3-6 (STX / Group I) | GAD100 / 104555 | DKE100 / BY40035AU | Available — inquire |
| 3×4-8 (STX / Group I) | GAE100 / 104557 | — | Available — inquire |
| 1.5×3-8 (MTX / Group I) | GAC100 / 104556 | DAF100 / DY46070A | Available — inquire |
| 2×3-8 (MTX / Group I) | GYB100 / D06628A | DAG100 / DY46161A | Available — inquire |
| 3×4-8 (XLTX / Group I) | GAE100 / 104557 | DYC100 / BY40035AV | Available — inquire |
| 1×2-10 (LTX / Group II) | GAF100 / 24741 | DAH100 / DY46950A | Available — inquire |
| 1.5×3-10 (LTX / Group II) | GAGG100 / 24745 | DAJ100 / CY22118A | Available — inquire |
| 2×3-10 (LTX / Group II) | — | DAN100 / CY22235A | Available — inquire |
| 3×4-10 (LTX / Group II) | GAH100 / 104878 | DAQ100 / DY47208A | Available — inquire |
| 4×6-10 (XLTX / Group II) | GYC100 / D06638A | DYD100 / BY40035AW | Available — inquire |
| 1.5×3-13 (XLTX / Group II) | GAJ100 / 24960 | DAU100 / CY22344A | Available — inquire |
| 2×3-13 (XLTX / Group II) | GAL100 / 24961 | DAV100 / DY50172A | Available — inquire |
| 3×4-13 (XLTX / Group II) | GAN100 / 24962 | DAW100 / DY33074A | Available — inquire |
| 6×8-13 (XLTX / Group II) | GAP100 / D00452A02 | DNA100 / DY32218AA | Available — inquire |
| 8×10-15 (XLTX / Group III) | GAS100 / 24963 | DNE100 / DY51013A | Available — inquire |
| 3×6-16 (Group III) | — | DNB100 / DY48876AA | Available — inquire |
| 6×8-16 (Group III) | GAT100 / D02450A | DNF100 / DY30546A | Available — inquire |
| 8×10-17 (Group III) | — | DNH100 / CY29134A | Available — inquire |
Need full interchangeability data for your specific pump size? Send us your pump nameplate details — we’ll provide a complete cross-reference and quotation within 48 hours.
Disclaimer: Goulds® and 3196 are registered trademarks of ITT Corporation. Durco® and Mark III are registered trademarks of Flowserve Corporation. ANSI Pumps Pro is an independent aftermarket manufacturer. Part numbers are used for cross-reference identification purposes only.